CN100491413C - Melt fracture reduction - Google Patents

Abstract

Melt fracture is reduced, without the necessity of polymer processing-aid additives specifically designed to alleviate exit region surface melt fracture phenomenon, by heating at least a portion of the die through which the polymer is extruded. The die exit region is maintained at a temperature above the bulk melt temperature of the polymer extruded through the die exit hole.

Description

The minimizing of melt fracture

Invention field

The present invention relates to be used for extruded polymer man-hour with method and apparatus that reduces extrudate distortion and/or surfaceness and the extrudate, particularly pellet that uses this method and apparatus to produce when polymkeric substance adds by die head.

Background of invention

When standing high speed by resin forming equipment, many resins for example comprise that poly polymkeric substance always is easy to impaired and produces polymer-extruded composition deformation and surfaceness, particularly " shark skin ".Such phenomenon (this paper is called outlet area surface melt fracture or " SMF ") be it seems under many circumstances, includes but not limited in the die head meeting generation that is used for granulation, squeezes sheet or blown film.At conventional resin forming equipment for example in die-type, the underwater granulator, SMF may be the source of many for example following downstream processing problems: the pellet of the generation of polymer fine particles, the fouling of pellet moisture eliminator, bad dehydration, the pellet tap density of reduction, bad accumulated solids feed bin flow, the physical condensation when mixing with other component in the processing of downstream and the final polymer parts on inhomogeneous defectiveness surface.

Aforementioned phenomenon is bigger to the influence of some resins than other problem.For example, the LLDPE resin uses titanium base, Zielger-Natta (Z/N) catalyzer or IVB family base (for example Zr or Ti) metalloscene catalyst production usually.Find that the LLDPE of metallocene catalyst (" mLLDPE ") is usually low than its Z-N-type counterpart at the about SMF that stands for 20% time of shear stress level.Usually, observe and have melting index to be less than or equal to the LLDPE resin (if regulation in addition, term used herein refers to the resin of Z/N and metallocene catalyst) of about 1.0dg/min (ASTM method D-1238, program B) responsive especially for SMF.

Under the specific purpose that reduces or eliminates polymkeric substance SMF phenomenon, researched and developed the additive that is designed to polymer processing aids (PPA), and conventionally added such additive certainly.For example, 6,187,397 suggestions of US patent use fluorinated elastomer as processing aid " with conventional ratio ... be generally about 500ppm ".For example, also referring to, US patent 6,552,129; 6,017,991; With 5,089,200.

Proved PPA for secondary manufacturers, for example how much useful film converter is.But, when in conventional tablets press, initial polymer being processed into pellet, primary polymer manufacturers, promptly polymer processing person does not recognize that the inhibition of the SMF that additive causes helps the minimizing of PPA equally.Introducing PPA has increased the manufacturing cost of product and may be unacceptable in the finished product.In addition, additive method is low in efficient aspect the SMF phenomenon under industrial high flow capacity processing conditions, particularly for the mLLDPE resin.

With the micro-roughness in die capillaries or die head exit hole, the selection of die capillaries material and the reason that the capillary geometry shape is assumed to SMF.These influence effect and are called some variation and inconsistent results that report in " micro-roughness effect " and the soluble open source literature.Although can obtain minor modifications by for example nib or kapillary being polished for those die heads with a large amount of defectives, described improvement can not improve or eliminate SMF basically.

US patent 6,474,969B1 discloses die head and the die head assembly that is used in combination with underwater granulator.Die head has the coil heats element (referring to Fig. 1) that is described as the upstream (being far-end) from the die head exit hole by the patentee, and according to this patent, its polymkeric substance that has reduced or eliminated in the die head solidifies.

The inventor is surprisingly found out that near heating exit surface die head hole wall or exit surface place (promptly the most approaching) has reduced or eliminated the exit region surface melt fracture in the polymkeric substance of extruding by molding device.

Summary of the invention

The present invention relates to a kind ofly be used for extruded material man-hour to reduce the extrudate distortion and/or from the method and apparatus of the surfaceness (being commonly referred to as " SMF ") of exit region surface melt fracture when material adds by the moulding aperture.

In one embodiment, this material is that polymkeric substance and moulding aperture are die head.

In one embodiment, this method comprise near the heating exit surface or the die orifice wall at exit surface place to reduce or eliminate the exit region surface melt fracture in the polymkeric substance of extruding by die head.

In another embodiment, this device comprises die head, wherein with near heating to small part die orifice capillary wall exit or the outlet.

In another embodiment, the present invention relates to does not a kind ofly need to use the polymer processing aids additive to promote to alleviate the method for exit region surface melt fracture phenomenon.

In another embodiment still, with respect to for the mass polymer performance of die head, polymer materials than the polymer layer generation of low-viscosity layer by using well heater local heating die head wall and directly contacting with this wall.In preferred embodiments, between the heat-eliminating medium insulating material is being set between die head material and the well heater and/or at die orifice and with polymer-extruded.

In going back an embodiment, provide a kind of equipment so that conventional die head device is retrofited so that reach purpose of the present invention.

In addition, an embodiment comprises the polymer-extruded thing of producing by apparatus and method according to the present invention, particularly pellet.

Therefore, an object of the present invention is to provide a kind of method and apparatus that reduces or eliminates the SMF in the resin extruded thing.Another purpose provides a kind of method and apparatus that pellet with visible SMF can be provided.

With reference to following detailed description, embodiment preferred, embodiment and accompanying drawing, these purposes and other purpose, feature and advantage will become apparent.

The accompanying drawing summary

Fig. 1 illustrates expression embodiment of the present invention according to the position of well heater of the present invention.

Fig. 2 illustrates expression embodiment of the present invention according to the position of well heater of the present invention and isolator.

Fig. 3 explanation has another embodiment of the invention of well heater and isolator.

Fig. 4 explanation has well heater, isolator and thermopair another embodiment of the invention with cavity.

Fig. 5 explanation is particularly suitable as the direct heating mouth mould circle of remodeling parts, and it is one aspect of the present invention.

The tablets press that Fig. 6 explanation has the prior art of water tank.

The embodiment of Fig. 7 explanation improved tablets press according to the present invention.

The embodiment of used inserts in Fig. 8 explanatory view 7, it comprises well heater and insulating element.

Fig. 9 explanation is particularly suitable as another embodiment of the direct heating mouth mould circle of remodeling parts, and it is one aspect of the present invention.

Figure 10 explanation is according to remodeling parts of the present invention.

Describe in detail

The present invention relates to a kind of disconnected be used to reducing or eliminating surperficial melt relevant with die head in the material Split the apparatus and method of (this paper is commonly referred to as SMF), it is by the outlet of the equipment that passes at material Aperture place or near at least one table of the described material that a kind of heating discharges from described aperture is provided The device of surface layer and finishing. In one embodiment, surface layer material is heated above approaching The temperature of the outlet body melt temperature of the described material in described outlet aperture. As used herein , term " body temperature (bulk the temperature) " meaning refers to the specific horizontal stroke at fluid The temperature that section is measured, condition are that fluid collection with this cross-section is in cup and it is filled Divide and mix. The cup temperature is in resin forming outlet (for example, die head exit, injection as used herein Nozzle etc.) locates the body temperature measured. This definition and the Whittington ' s of cup temperature The third edition of Distionary of Plastics (1993) is consistent.

In one embodiment, material is that polymer and aperture are die head.

According to embodiment of the present invention, in the situation of not using the polymer processing aids additive Lower, reduced exit region by the heated polymerizable thing via at least a portion of its die head of extruding The surface melt fracture. In a preferred embodiment, the heating part of this die head is from mould Near the exit point of the polymer of head or exit point place is namely near the die head exit opening part. At one In the embodiment, between die head exit and cooling medium, provide the thin layer of insulating materials, as following Described in detail.

In a preferred embodiment, near exit surface or the exit surface place with the die orifice wall Finite length be heated above the temperature of extruded product body melt temperature, i.e. cup temperature.

In another preferred embodiment, at least a portion of die head is heated above is squeezed The resin that goes out extrude the about 30 ℃ temperature of body melt temperature, it is molten preferably to be higher than the extruded product body Melt the about 30-170 of temperature ℃ temperature.

In another embodiment, by heating at the polymeric layer that contacts with the die capillaries wall In cause rheology modified. In the example of described modification, polymeric material than low-viscosity layer (phase For the bulk polymer characteristic by die head) (or excessively add by using the heater local heat Heat) the die head wall directly contacts and produces with wall with polymeric layer. Further describe as following, In one embodiment, the die head wall material can be limited by heater itself, just looks like to have brill The same in logical its cartridge heater of passage; Or in another embodiment, heater can be put Extrude in restriction passage the die head wall material the back and near.

In a preferred embodiment, with wall-when the strata compound contacts, polymerization feed streams Body temperature because very short time of staying and relatively changing. In another preferred side of enforcement In the case, the thermal treatment zone only need to be on the part near the total length of the die head of opening, but more preferably Comprise near the stub area of the opening portion of die orifice, optional insulation material layer is provided. Such as this Literary composition is employed, if do not stipulate in addition, term " insulation " meaning is heat insulation and electric insulation. Provided hereinafter the example of described material.

Another embodiment comprises the extrudate that forms by former, preferably passes through comminutor The pellet that forms (comprises and contains polyolefin and can or can not comprise in addition polymer processing aids Polymer composition), wherein said extrudate or pellet do not have as seen (for naked eyes) Die head exit surface melt fracture. Specifically, there is multiple PPA based on fluorinated polymer, And thereby in another embodiment, extrudate or pellet comprise and contain polyolefin and do not contain The polymer composition of fluorinated polymer, wherein said extrudate or pellet do not have visible die head The exit surface melt fracture. In a rear embodiment, for breaking except die head exit surface melt Reason beyond splitting can add additive for example antistatic additive, slipping agent etc., and condition is them It or not fluorinated polymer.These additives are possible so that the surface is obviously inhomogeneous, but do not think it Help die head exit surface melt fracture.

In a preferred embodiment, pellet is mainly by not containing fluorinated polymer or more generally The melt index that polymer composition consists of and mLLDPE has that does not contain polymer processing aids Be less than or equal to about 2.0dg/min, or in another embodiment, be less than or equal to approximately 1.0dg/min as passing through ASTM method D-1238, program B measures, wherein said pellet is tool not Visible die head exit surface melt fracture is arranged.

Although benefit of the present invention can reach with multiple former, specific advantage is to make For example underwater pelletizer, wire rod comminutor, liquid-ring type comminutor obtain with comminutor.

In the wire rod tablets press, melting material is the form of wire rod and leaves forcing machine, and described wire rod enters cooling tank.After cooling tank is discharged, the material wire rod enters stapling machine.Stapling machine can comprise the metal lip, and an end of material wire rod is suspended on the metal lip and is rotated the blade cut-out until this end.

In underwater granulator, extrudate is discharged by the opening in the underwater die face.The fritter of extrudate or " droplet (drop) " use the rotating blade with edge of a knife that contacts with die face to cut off.In this respect, make cooling water circulation cooling room by sealing die face and blade so that water flows through die face and blade.

In the water-circulation type tablets press, extrudate is discharged through the die orifice of the circular port template of forcing machine.The fritter of extrudate or " droplet " use the rotating blade with edge of a knife that contacts with die face to cut off.Fused extrudate " droplet " is put to around the circular port template via blade and flows in the cylindrical cascade of outside.When extrudate was run into water, surface cool formed pellet, and described pellet further cools off when they flow to screen separators downwards, in described screen separators most of water is separated from pellet.

More generally, the present invention is applicable to any wherein material equipment of (for example being used to extrude the seam pattern head of a film) from the aperture and coming out, and any molding device (such as but not limited to those equipment with circular opening that are used for extrusion blow molding film), or the like.Particularly be molten state and under the situation of aperture discharge, can recognize advantage of the present invention at material.

The present invention is specially adapted to resin material, comprises hydrocarbon resin, Gum Rosin, terpine resin or the like.In a preferred embodiment, resin is polyolefine or polyolefin blends (it can further comprise another kind of material).Resin can be used for multiple end-use usually, for example film, moulded product, tackiness agent or the like.Equally, according to end-use, composition can comprise resin and the additive (but having got rid of the polymer processing aids that is designed to reduce or eliminate SMF especially) that is fit to.In a preferred embodiment of the invention, resin is a film-forming resin.

In another preferred embodiment, composition comprises polyolefin compositions, more preferably is selected from polyethylene, polypropylene, polyethylene and polyacrylic multipolymer and terpolymer and composition thereof.

In a preferred embodiment, composition can comprise one or more various types of polyethylene known in the art, comprises new LDPE (film grade), linear low density of polyethylene, medium-density polyethylene and very low density polyethylene.

New LDPE (film grade) (" LDPE ") can under high pressure use radical initiator preparation and the density that has usually is 0.916-0.940g/cm ³LDPE is owing to the long-chain side chain of the larger amt that extends out from the host polymer skeleton is also called " branching " or " inhomogeneous branching " polyethylene.Also known (is 0.916-0.940g/cm in the equal densities scope ³) for linear and do not contain the polyethylene of long-chain side chain; This " linear low density of polyethylene " (" LLDPE ") can adopt conventional Ziegler-Natta catalyst or adopt metalloscene catalyst production.Higher density LDPE is generally 0.928-0.940g/cm ³, be called medium-density polyethylene (" MDPE ") sometimes.Having more highdensity polyethylene is high density polyethylene(HDPE) (" HDPE "), and promptly density is higher than 0.940g/cm ³Polyethylene and its usually adopt the Ziegler-Natta catalyst preparation.Also known very low density polyethylene (" VLDPE ").VLDPE can have the different methods production of different performance polymkeric substance by many generations, but it can be described as density usually less than 0.916g/cm ³, be generally 0.890-0.915g/cm ³Or 0.900-0.915g/cm ³Polyethylene.

All above-mentioned materialss all are applicable to the method according to this invention, and therefore can be made of these compositions according to pellet of the present invention.

In one embodiment, polyolefine can be a homopolymer, and perhaps it can be a multipolymer.For the present invention, in the definition of multipolymer, comprise terpolymer and even will be more the different monomers of high number introduce more senior (higher order) resin in the polymkeric substance.

Under poly situation, multipolymer can be for example polyethylene and one or more comonomers, and described comonomer is selected from carbon monoxide, vinyl ester for example vinyl acetate, alkyl acrylate or alkyl methacrylate, maleic anhydride or (methyl) glycidyl acrylate or the like as non-limiting example.Other comonomer that is fit to comprises alpha-olefin, the example is 1-butylene, 1-amylene, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-undecylene, 1-dodecylene or the like, and 4-methyl-1-pentene, 4-methyl isophthalic acid-hexene, 5-methyl isophthalic acid-hexene, vinyl cyclohexene, vinylbenzene or the like.

Also can be described as according to device of the present invention and can be used for any thermoplastic polymer, comprise homopolymer and have narrow and the multipolymer of comonomer distribution (narrow and wide, as to comprise bimodal molecular weight distribution), for example ethene and one or more alhpa olefins (C ₃-C ₂₀) multipolymer, ethylene copolymer (EPDM or EODM with degree of unsaturation, be ethylene-propylene-diene or ethylene-octene-diene), or for example above-mentioned polymkeric substance of other polymkeric substance (for example, LDPE), ethylene vinyl acetate copolymer, ethylene acrylic acid co polymer, styrenic block copolymer (SBS, SEBS, SIS or the like, i.e. styrene/butadiene/styrene, styrene/ethylene/butylene/styrene (hydrogenation SEBS), styrene/isoprene/styrene or the like), basically the random multipolymer of at least a alpha-olefin and at least a aromatic vinyl or the vinyl aliphatic series comonomer that is obstructed comprises ethene-styrene copolymer, syndiotactic polystyrene, random polystyrene, hydrogenant polyvinyl tetrahydrobenzene, PET (poly-(ethylene glycol terephthalate)), PBT (polybutylene terephthalate), PEN (poly-naphthoic acid glycol ester), poly(lactic acid), thermoplastic polyurethane, polycarbonate, nylon, poly-(methyl methacrylate), ABS (vinyl cyanide/butylene/styrene), polysulfones, polyphenylene oxide, polyphenylene sulfide, polyacetal and polyvinyl chloride.

In one embodiment, material also can be selected from or comprise linear basically ethene polymers (SLEP), and it is the homogeneous polymer with long chain branching, and is as US patent Nos.5, disclosed in 272,236 and 5,278,272; They are optional from the polyolefin elastomer (POE) available from DuPont Dow Elastomers LLC; And they are optional from the polyolefin plastomers (POP) available from Dow Chemical Company.

In another embodiment, composition be (i) ethene and at least a 2-6 of a containing carbon atom saturated carboxylic acid vinyl ester multipolymer, (ii) ethene and at least a alkyl contain the multipolymer of the alkyl acrylate of 1-10 carbon atom or alkyl methacrylate, (iii) further with the above-mentioned multipolymer of maleic anhydride or (methyl) glycidyl acrylate or the (iv) mixture of at least two kinds of above-mentioned multipolymers.

In another embodiment, composition comprises that vinyl acetate (that is, EVA), preferably comprises 10-40wt%, more preferably 12-28wt%, and even the unitary EVA of vinyl acetate of preferred 12-25wt% as comonomer.

Polyolefin compositions also can comprise polypropylene, and it can be homopolymer polypropylene or polyacrylic random or segmented copolymer, or its blend.Homopolymer can be Atactic Polypropelene, isotactic polyprophlene, syndiotactic polypropylene and blend thereof.Such blend can comprise so-called impact-resistant copolymerized thing, elastomerics and plastomer, and its any can be the physical blending thing or the on-the-spot blend of polypropylene and one or more polypropylene copolymers.Preferred comonomers in the polypropylene copolymer comprises and is selected from ethene and C ₄-C ₂₀Alpha-olefin derived unitary monomer.

In one embodiment, resin combination can be various types of polyolefine (comprising conventional film forming polyolefine for example polyethylene and/or polypropylene) and self mixture of the film forming material of shape (for example ethylene elastomer, it is the polymkeric substance that comprises ethene and propylene) not usually.Composition also can comprise ionomer for example polyethylene or ethylene copolymer ionomers.Many other resins are also expected, for example adopt functionalized polystyrene of borine monomer, alkylsulfonyl or the like and polyolefine.

Polyolefine can use produces polyolefinic any known catalysts system (for example Ziegler-Natta or metalloscene catalyst) production, and can be by for example slurry (it can utilize chromium-based catalysts), solution or gas phase process preparation.

In a preferred embodiment, resin comprises the polyolefine that uses Ziegler-Natta catalyst to produce, and more preferably resin comprises the polyethylene that uses Ziegler-Natta catalyst to produce.

More preferably polyolefine is the polyolefine of metallocene catalyst.As used herein, term " metalloscene catalyst " is defined as containing at least a metallocene catalyst components that the cyclopentadienyl structure division (Cp) of one or more replacements or non-replacement combines with the 4th, 5 or 6 group 4 transition metals (M).

The metalloscene catalyst precursor need adopt the activation of suitable promotor or activator to obtain " activatory metalloscene catalyst ", promptly to have making the organometallic complex of the empty hapto of alkene coordination, insertion and polymeric usually.Activated catalyst systems not only comprises metallocene complex usually, and comprises activator, for example aikyiaiurnirsoxan beta or derivatives thereof (preferred MAO), ionization activator, Lewis acid or its combination.Alkylaluminoxane also is suitable as catalyst activator in addition.

The catalyst system preferred negative is loaded in carrier, and usually inorganic oxide or muriate or resinous material are for example on the polyethylene.

Aforementioned catalyzer and technology are well known in the art, and are described in, for example ZIEGLERCATALYSTS (eds., Springer-Verlag 1995 for Gerhard Fink, Rolf Mulhaupt and Hans H.Brintzinger); People such as Resconi, Selectivity in PropenePolymerization with Metallocene Catalysts, 100 CHEM.REV.1253-1345 (2000); And I, II METALLOCENE-BASED POLYOLEFINS (Wiley﹠amp; Sons, 2000), and a plurality of patent, for example WO96/11961; WO 96/11960; US patent Nos.4,808,561; 5,017,714; 5,055,438; 5,064,802; 5,124,418; 5,153,157; 5,324,800; Nearer example is US patent Nos.6,380,122 and 6,376,410; And WO01/98409; And this paper is incorporated herein by reference them.

In a preferred embodiment, the material of discharging from the aperture is that melting index is less than or equal to about 2.0dg/min, it perhaps in another preferred embodiment linear low density of polyethylene (mLLDPE) resin that melting index is less than or equal to the metallocene catalyst of about 1.0dg/min (ASTM method D-1238, program B).

Embodiment

Following examples are intended to illustrate the present embodiment preferred of the present invention, and wherein same from start to finish numeral refers to same parts.Multiple improvement and variation are possible, and should be appreciated that in the scope of appended claim, and the present invention can be different from the specifically described mode of this paper and implement.

Embodiment 1

As shown in Figure 1, manufacturing has the single capillary forcing machine die head 1 of improved brass pattern head main body 3, so that by heating unit 5 hot spots kapillaries, described heating unit 5 comprises stub area capillaceous near die orifice 7 by means of Die-head connecting sleeve 9, described Die-head connecting sleeve 9 is also made by brass, can adopt the bolt (not shown) to be connected on the die head.Internal diameter (ID) is that the well heater of 3.2mm and length L=15.2mm is the cartridge heater available from the Watlow GmbH of Germany.Cartridge heater is with to extrude the aperture pattern concentric, and keeps uniform heating with the entire circumference in the aperture outlet forming capillary wall near the capillary outlet place.Slit in the Die-head connecting sleeve 9 allows the electric wire (not shown) to pass through, and it is installed on the varitran with input of control voltage and therefore heating.Packing ring or other tightness system (for example tackiness agent) can also be shown among Fig. 2-4 being disposed between main body 3 and Die-head connecting sleeve 9 by numeral 8 indicated optional slits.

Polymkeric substance is discharged in " upstream " of the forcing machine die head 1 that is entered part of the die head by numeral 11 indicated places and at die orifice 7 places.Representational or exceed in the various polymer flow speed ranges of industrial operation rate of extrusion, with near the die capillaries of die orifice 7 by electric heater 5 be heated to 245-372 ℃ or more than extruded product body melt temperature about 30-170 ℃ all temps.When making that minimally influences body temperature, heater temperature and flow rate realized successful test.Adopt this mode that the various types of mLLDPE of being purchased polymeric articles (following detailed description) are extruded through die head device.Do not use water tank.

Having found that this die ends heating technique can make is purchased EXCEED ^TM350D65 (the mLLDPE resin that contains PPA) extrudes with 24kg/h through 0.125 inch die capillaries, and does not have any visible or tangibly SMF vestige.Described flow rate has exceeded under above-mentioned processing conditions for above-mentioned resin three times of the proper flow rate limit of SMF.If not indicated otherwise, flow rate described herein is each hole.

Embodiment 2

The EXCEED that use is purchased ^TM350D60mLLDPE (being similar to the mLLDPE that uses among the embodiment 1, except not containing PPA) repeats above-mentioned test.Very surprisingly, even do not observe surface irregularity up to the extrudate under the 28kg/hr by checking in vision or the sense of touch in flow rate yet.

But the result of relevant elimination SMF who uses the mLLDPE do not contain PPA is only at the temperature (T of die head exit _{Die head exit}) be higher than melt temperature (T _Melt) obtain under the about 170 ℃ situation of about 30-.

Embodiment 3

Plant-scale water logging granulating extruder that then will have a plurality of die heads of water tank and the same modification in embodiment 1 and 2 is used to simulate plant-scale test.The result who obtains is also observed good like that not as adopting in the single capillary test.Visual observations is to SMF.Without wishing to be bound by theory, it is believed that in the cooling effect of die head exit corner water the overheating effect of observed SMF under significantly lower flow rate is had enough negative impacts.

Embodiment 4-6

Then single capillary forcing machine die head 1 is improved to make the influence of the isolated water coolant of die head exit better.In embodiment 4, as shown in Figure 2, die orifice is improved so that insulation inserts 21 to be provided, described inserts 21 is the concentric and formation part capillary wall with die capillaries also.Kapillary forcing machine die head is identical with Fig. 1 in addition, as with same digital indicated.

In embodiment 5, as shown in Figure 3, insulation layer 31 is set to reduce thermosteresis for other parts of die head around heating unit 9.Have, other parts of forcing machine die head are identical with Fig. 1 again, as with same digital indicated.

In embodiment 6 (Fig. 4), die capillaries 41 is shortened with respect to embodiment 4 and 5, in the Die-head connecting sleeve 9 that comprises well heater 5 and isolator 45 die head inserts 43 is set, as among the embodiment 5, well heater and isolator are concentric on to provide heat to die head exit 7 with die capillaries 41.Other chamber 47 is set polymkeric substance is further packed in (telescope) kapillary 41.The cavity 49 that is provided for thermopair is with the monitoring die head temperature.

The insulation layer method of PBI as insulating material used in discovery shown in Fig. 2-4, at the single mode head of the Capillary Flow speed of using each hole up to 24kg/hr, by capillary wall temperature being adjusted to up to 390 ℃, the mass polymer melt temperature is 240 ℃, exist with do not have PPA under use MI=1dg/min and density as the identical mLLDPE resin of 0.917g/cc, the laboratory test of success is doubled.

Insulation layer or inserts can be for example with above embodiment 4-6 in the same PBI (polybenzimidazole), but can also to be other be fit to is the material of isolator for it, but for example quenching that runs into respect to die head material and/or extrudate or the pottery of other high temperature plastics for the heat-eliminating medium and mechanical workout preferably at room temperature have the material of low heat conductivity.In a more preferred embodiment, the thermal conductivity that has of this material be steel thermal conductivity about 1% or littler.

Within the scope of the invention, those skilled in the art it can also be appreciated that the heating unit that can use the heating unit that uses in the foregoing description.For example, can use for example aforementioned US patent 6,474, the solenoid type well heater (it separates by die head material and capillary wall) that uses in 969 or around the cartridge heater at capillary wall interval, condition is can be local and providing uniform heating basically near the die head exit place, thus, in one embodiment, producing with respect to more low viscous polymer material layer for the mass polymer characteristic of die head near the die head exit place.

Embodiment 7

In another embodiment, the mouth mould coil component 51 in the shop drawings 5, it still is monolithic well heater (monolithic heater).In mouth mould coil component, between two copper electrodes 55 and 57, there is slit 53, applies voltage to described slit 53.Electric current flows to another electrode from an electrode through port mould circle 59.Mouthful mould circle is made by the Inconel(nickel alloys) of a side-cutting side (cutting side)-be coated with zirconium white insulation layer that forms by physical vapor deposition.Zirconia layer can be by other mode that is fit to, and for example spraying technology (for example, plasma spraying) applies.Because a mouthful mould circle is made by the material with much higher resistivity (almost than high 2 orders of magnitude of copper), electric energy will mainly be consumed the heat in mouthful mould circle.Mouth mould circle can be by other material that is fit to, and for example stainless steel is made, and insulating coating can be any suitable type, for example chromic oxide.Form 14 capillary bore 61a, 61b or the like and be complementary with the capillary wall with the cut surface of the extrusion device of Link Port mould circle 51, zirconia coating is towards the outside and become cut surface this moment, and described cut surface is connected mutually with cutting blade.Under situation about forming before the gas deposition insulation layer, stopper is placed the influence that is not subjected to vapor deposition process in the capillary bore with the protective hair tubule wall at capillary bore.In preferred embodiments, isolator is fully polished so that the cutting blade of tablets press relies on (ride on) onboard with minimal friction forces.

Temperature test shows that the mouth mould circle 51 with uniform thickness produces higher temperature in the internal diameter of ring.In order to compensate, make have tapering mouth mould circle to reduce mouthful thickness of mould circle towards internal diameter gradually, keep the constant so that sealing problem of thickness around capillary bore and the electrode to minimize simultaneously.The optimum proportion of finding inner thickness and outside thickness is about 1.1cm/1.5cm.In this case, find that from outer radial internal diameter tapering be about 20 degree.Observe the more violent heating (higher temperature) of existence around capillary bore, it is believed that this is mouthful obvious advantage of mould circle embodiment.But, under the situation of aforementioned taper design, find that temperature is very even in the hole between internal diameter and external diameter, in the operating temperature range of being studied, change being no more than 10 ℃.

Fig. 5 for example understands one embodiment of the invention, and it is made with existing mouth template modification in construction.The parts of similar mouthful of mould circle 51 can be constructed in accordance at many existing granulation mouth template pore structures the SMF technology is retrofited, and within the scope of the invention, it will be appreciated by those skilled in the art that the structure according to molding device, many other designs also are fine.

With Fig. 5 is example, is directly connected to plate on the die cuts surface and comprises and sectional hole patterns that the capillary bore pattern of the mouth template of retrofiting is complementary.In Fig. 5, optional epipharynx part (for example being defined by digital 52a, 52b, 52c) and/or outer lip part (for example by 54 definition of numeral) can be used for mouth mould coil component is remained on the die surfaces by bolt, welding, tackiness agent or the like.Can utilize according to the device of described embodiment as resistance or induction heating technique to eliminate at the independent cartridge heater of each kapillary needs in the mouth template.Plate is directly connected on the die cuts surface as remodeling.

Fig. 7 for example understands the preferred embodiments of the invention, also can be with reference to prior art as shown in Figure 6.

Fig. 6 for example understands the underwater granulator of the prior art that is connected with water tank 73.Make things convenient for cutting blade not shown in order to observe.Water enters water tank 73 and discharges at outlet 77 places with the pellet that forms at inlet 75 places.Polymer melt admission passage 79 and (only illustrate 3 for convenience from a plurality of die heads aperture 81a, 81b, 81c; In fact usually have a plurality of apertures) discharge.Still in order to observe conveniently the cutting blade that outlet not shown and aperture 81a, 81b, 81c is connected.Die head 83 is usually by placing the optional cartridge heater heating in the cavity 85.Mouth template can only be used to remedy thermosteresis from the die head assembly usually by optional mouth template heater heats to common technological temperature and mouth template.

Fig. 7 for example understands the embodiment according to underwater granulator 91 of the present invention, in order to observe convenient not shown cutting blade.The layout of cutting facility is conspicuous to those skilled in the art.Be similar to Fig. 6, water enters water tank 73 and discharges at outlet 77 places with the pellet that forms at inlet 75 places.As in the prior art, polymer melt admission passage 79 and discharge from one or more die head exits 95.Mouth template 93 can be by the heater heats in the cavity 85.Die head exit (it is movably) improves according to the present invention.In Fig. 8, die head exit 95 has been carried out detailed explaining.Conventionally can provide a plurality of outlets aperture that generally includes according to device of the present invention, then it is fixed on the mouth template 93 by bolt 99 by mouth mould circle or the similar devices shown in Fig. 6.Not shown in Figure 8 in order to observe convenient whole mouthful of mould coil assembly, and among the Figure 10 that further discusses below as can be seen.

Fig. 8 has shown the preferred embodiments of the invention.Identical among mouth template 93 and water tank (representing) and Fig. 7 with parts 96.Insulating washer (also existing in Fig. 6 and 7) is represented with parts 97.Polymer melt enters kapillary at passage 79 places and 7 places are discharged to the downstream in the aperture, and is the same with the figure of front.Movable-component (95 among Fig. 7) comprises well heater 103 and auxiliary heater (associated heater) and the preceding isolator 101 of plate that is placed within the movable-component 107, and it is by making with mouth template 93 identical materials.With isolated with packing ring 105 with mouth template 93 at the concentric assembly of opening 7 place's terminated extrusion die kapillaries.

Fig. 9 has shown the embodiment of Fig. 5, but understands that for example preferred embodiment according to of the present invention mouthful of mould coil assembly 111 is to provide the direct resistive heating to mouth template (for example, 93 among Fig. 8).Copper electrode is represented with numeral 55 and 57, with the same among Fig. 5.Mouth mould coil assembly 111 can be bolted on the forcing machine in order to fixing by means of a plurality of bolt hole 113a, 113b or the like.Should can install around outside set ring 114 by (mouthful mould) circle, this outside set ring is bolted on the forcing machine by bolt 115a, 115b or the like, and positioned internal circle 116 is bolted on the forcing machine by bolt 117a, 117b or the like.Usually with numeral 113,115 and 117 bolts of representing typically to center on the arranged in patterns of the central shaft of mouth template with one heart.A plurality of cavity 119a, 119b shown in the dotted outline or the like as previously mentioned (for example, the cavity 85 among Fig. 6 and 10) provide well heater for mouth template.A plurality of kapillary openings (all being similar to the outlet 7 among Fig. 8) are represented with numeral 121 usually.

Figure 10 as Fig. 5 or Fig. 9 major electrical components adopt bolt 131a and 131b to be bolted to being connected of mouth mould circle 111 on the mouth template 93 at positioned internal circle 116 places.Bolt 133 is connected to the outside set ring 135 of mouth mould circle on the mouth template.The details of die head inserts 95 is not shown in this Figure, but identical with situation shown in Fig. 8.Have, polymer melt enters with 79 passages of representing and according to the present invention and is expressed into a plurality of moulding aperture shown in 7a, 7b and the 7c (the die head inserts 95 that comprises heating) in addition again.

The difference of observing the extrudate slickness mainly is the influence of following factor: (a) geometrical shape of heater block (for example, the position of well heater), (b) length of heated opening portion and (c) temperature of heated outlet area.When testing under water, buried die head length and water temperature all have remarkably influenced to the size of the heat flux in die head exit zone.Within the scope of the invention, those of ordinary skills can control aforementioned parameters so that reach purpose of the present invention.

In the remarkable enhancing of not observing the influence that is exported configuration aspect the SMF characteristic.Straight shape outlet, round exit and counterbore outlet are general and all benefit from the present invention.Can adopt other how much modifications, for example die head is tapered.The location (for example level or vertical) of not observing the kapillary delivery port has significantly strengthened benefit of the present invention.

The die orifice that use is designed to duplicate industrial forcing machine configuration is arranged the quantity of die orifice and the influence of arrangement is studied.Present industrial forcing machine uses each slit to have the slit class mouth template of 1,2 or 3 row's die orifices.Row's number of not observing die orifice to the result influential and any aforementioned variation all can under the situation of any industrial forcing machine, use, irrelevant with the arrangement of die orifice.

About the die head material, advantage of the present invention can see in the die head of multiple material, and for example stainless steel die head, carbon steel die head, ceramic die head, brass pattern are first-class etc.Can use around the hardened inserts (for example wolfram varbide or the like) of die holes outlet.

Trade(brand)name used herein is used ^TMSymbol

Symbolic representation shows that this title can be subjected to some trade mark right protection, and for example they can be the registered trademarks in each compass of competency.

All patents that this paper quoted and patent application, test step (for example ASTM method) and other document are to disclose consistent degree and to be introduced for reference with all authorities that this introducing wherein is allowed to the present invention comprehensively.

When having listed digital lower limit herein and numeral goes up in limited time, can expect the scope of any lower limit to any upper limit.Although specifically described illustrative embodiment of the present invention, should be appreciated that various other modifications all obviously and easily carry out to those skilled in the art, and do not deviate from the spirit and scope of the present invention.Therefore, and the scope that is not intended to appended herein claim is confined to embodiment as herein described and specification sheets, and claim should be interpreted as and comprise that all of patent novelty features are arranged among the present invention, comprise that the technician of the technical field of the invention can regard as all features of its equivalent.

Below invention has been described with reference to a plurality of embodiments and specific embodiment.Many modification have been advised according to the top those skilled in the art of being specifically described as.All these conspicuous modification are all in the four corner of claims.

Below describe preferred and preferred embodiment of the present invention in detail, in suitable, their uses capable of being combined, this is conspicuous to those skilled in the art within the scope of the invention.

An embodiment comprises the extrusion die assembly that comprises at least one die capillaries, and described die capillaries has initial upstream and (comprises to be used for receiving and have temperature T _MeltThe opening of polymer melt), be used to the final catchment (described thus polymer melt is discharged described extrusion die assembly) of carrying the intermediate zone of described polymer melt and stopping described extrusion die assembly at the exit opening place, aforementioned region arrangement adjacent one another are respectively, and comprise the heating unit that is used for described catchment, thus can be with described polymer melt local heating to being higher than T _MeltTemperature.Although the definite temperature that described catchment is heated to can be measured by routine test, heating make with polymer layer that the die capillaries wall contact in rheology modified by means of the heat generation.In the example of this modification, with respect to for the mass polymer characteristic of die head, more low viscous polymer material layer produces by using well heater local heating (or superheated) die head wall and polymer layer directly being contacted with wall.In preferred embodiments, the body temperature of polymerization feed streams is because very short residence time and change relatively during with the contact of wall-strata compound.Usually the body temperature change is no more than 10 ℃, preferably is no more than 5 ℃, more preferably no more than 1 ℃.

Another embodiment preferred of aforesaid method comprises: a kind of method that material is expressed into outside the molding device with outlet aperture, described material has body temperature at place, described outlet aperture, improves the temperature that the upper layer at least that comprises the described material that will locate near described outlet aperture is heated above the body temperature of place, described outlet aperture material.Another preferred embodiment of this method comprises: a kind of with the fluoropolymer resin process for granulating, this method comprises to be extruded the fluoropolymer resin melt by the extrusion die assembly that comprises at least one die capillaries with die head exit hole, improve to comprise and be heated to the described die capillaries of small part so that the temperature of die head exit part is higher than the temperature of fluoropolymer resin melt.

Any of the embodiment of aforesaid method can be in addition by one or more following preferred embodiment modifications: wherein near the high 30-170 of temperature ℃ of the temperature ratio copolymer resin melt of the part of exit opening place heating; Wherein said fluoropolymer resin melt does not contain polymer processing aids; Wherein said fluoropolymer resin melt comprises polyethylene; Wherein said fluoropolymer resin melt comprises mLLDPE; Wherein said fluoropolymer resin comprises LLDPE; Wherein said fluoropolymer resin melt comprises the LLDPE that melting index is less than or equal to 2.0dg/min, as measuring by ASTM method D-1238; Wherein said fluoropolymer resin melt comprises the LLDPE that melting index is less than or equal to 1.0dg/min, as measuring by ASTM method D-1238; The method according to this invention wherein, when extruding under 24kg/hr (each hole) by 0.125 inch die capillaries, any aforementioned polymer does not all have visible SMF.

Another embodiment comprises a kind of method of extrusion resin, and it comprises: the fused rosin products (a) is provided; (b) with described product feeding to molding device with at least one outlet opening; (c) described product being expressed into described hole enters in the quenching medium in addition; (d) the exit surface selectivity in described hole is heated above the temperature of temperature of extruded product so that form more low viscous thin surface at the internal surface place in the exit of molding device; Thereby reduced the irregular disengaging of extrudate when it leaves die holes.Preferred embodiment comprises following one or more embodiments: wherein resin is the polymkeric substance of the restriction of the generation that rate of extrusion is subjected to the whole surface inhomogeneity on extruded product when having by described molding device; Wherein resin is mLLDPE; Wherein resin is the polyethylene that melting index is less than or equal to about 1.0dg/min, and as passing through ASTM method D-1238, program B measures; Wherein resin is the mLLDPE resin that melting index is less than or equal to about 1.0dg/min, and as passing through ASTM method D-1238, program B measures; Wherein said molding device is the tablets press that is selected from underwater granulator, wire rod tablets press and water-circulation type tablets press; Wherein said hole is selected from: the seam pattern head that (a) is used for extrusion sheet; (b) be used for the seam pattern head of extrusion film; (c) be used for the looping pit of extrusion blow molding film; (d) be used for the die head of electric wire and cable coating; Wherein insulation layer places (if do not stipulate in addition, the insulation meaning as used herein is thermal isolation and electrical isolation) between molding device and the described quenching medium; The heating of the exit surface in wherein said hole is enough to improve the oilness of molten resin in the molding device, and the body temperature of the molten resin that do not raise; The source of wherein said heating provides by the whole resistance heater of the exit portion of formation shaping channel; Wherein insulation layer places between exit portion and the heat-eliminating medium; The source of wherein said heating is an induction heater; The source of wherein said heating is one or more electrically heated tubes.

Another embodiment preferred comprises following product of the present invention: comprise the moulded products of the resin that can pass through any preceding method acquisition, wherein said moulded products does not have visible die head exit surface melt fracture; The moulded products that comprises the resin that is obtained by any preceding method, wherein said moulded products do not have visible die head exit surface melt fracture; The pellet that comprises the resin that can pass through any preceding method acquisition, wherein said pellet do not have visible die head exit surface melt fracture; The pellet that comprises the resin that is obtained by any preceding method, wherein said pellet do not have visible die head exit surface melt fracture; Moulded products, extrudate or pellet by any preceding method preparation; With in addition more preferably when preparing, do not demonstrate any aforementioned moulded products, extrudate or the pellet of visible SMF by any preceding method, described preceding method is included in and has or do not exist that the kapillary die head by 0.125 inch is the step of extrusion resin under the 24kg/hr in speed under one or more polymer processing aidses.The embodiment of any these moulded products, extrudate or pellet can comprise following qualification in addition: polymer composition comprises the LLDPE that mLLDPE that melting index is less than or equal to about 1.0dg/min, LLDPE that melting index is less than or equal to about 1.0dg/min, mLLDPE that melting index is less than or equal to about 2.0dg/min and/or melting index are less than or equal to about 2.0dg/min; Or polymeric composition is less than or equal to the LLDPE that the mLLDPE of about 1.0dg/min, LLDPE that melting index is less than or equal to about 1.0dg/min, mLLDPE that melting index is less than or equal to about 2.0dg/min and/or melting index be less than or equal to about 2.0dg/min by melting index basically and constitutes alternatively; Or polymer composition is less than or equal to the LLDPE that the mLLDPE of about 1.0dg/min, LLDPE that melting index is less than or equal to about 1.0dg/min, mLLDPE that melting index is less than or equal to about 2.0dg/min and/or melting index be less than or equal to about 2.0dg/min by melting index and constitutes (wherein melting index is by ASTM method D-1238, and program B measures) alternatively.

The preferred embodiment of said apparatus comprises: mouth template, and described mouth template comprises: (a) upstream face; (b) downstream face; (c) but in described upstream face, have first opening that can receive molten resin and at least one passage that in described downstream face, has second opening of resin melt extrusion; (d) near described downstream face with at described downstream opening place and the approaching well heater of described at least one passage.Preferred embodiment comprises one or more following embodiments: wherein said at least one passage is normally columniform and have basically a diameter uniformly from described upstream face to described downstream face; Wherein said well heater is concentric with described at least one passage; Wherein said at least one passage is by the part well heater, so that described part limits the described conduit wall near described downstream face; Comprise in addition with described well heater and described mouth template in abutting connection with and with near near the concentric insulating material of described well heater described at least one passage of described downstream opening; Comprise in addition with concentric near described at least one passage of described downstream face and be formed up to the insulating material of the described downstream face of small part at described second opening part; Comprise in addition with described at least one passage concentric and with to the described heating unit of small part in abutting connection with and at the insulating material of described exit opening place and described at least one channels abut; Wherein said mouth template be the monolithic mouth template (wherein term " monolithic " meaning is that parts are made of a slice as used herein, simultaneously, for example, in order to coating or dipping isolator as herein described to be provided and to place electrode so that necessary electric current input to be provided); Wherein said mouth template comprises first block of plate with described upstream face and has the second block of plate and the described well heater of described downstream face, and described first and second block of plate are by described at least one channel flow connection (wherein term " fluidly (fluidically) " look like be that the mobile fluid is relatively hindered from parts to parts between two parts) as used herein; Comprise a plurality of described at least one passage; Comprise with wherein said mouth template and to be selected from brass, stainless steel and Inconel ^TMMaterial; But wherein said insulating material be selected from high temperature plastics mechanical workout pottery, can be by sedimentary pottery of spraying technology and pottery that can be by the gas deposition deposition techniques; But wherein said insulating material be selected from high temperature plastics mechanical workout pottery, can be by sedimentary pottery of spraying technology and pottery that can be by the gas deposition deposition techniques.

Another embodiment preferred of device is: the extrusion die assembly comprises the mouth template with at least one passage, and described passage comprises by being used for receiving having body temperature T _MeltThereby the initial upstream that constitutes of the opening of polymer melt, be used to carry the intermediate zone of described polymer melt and stop the catchment that described extrusion die assembly discharged described polymer melt by described extrusion die assembly at the exit opening place, this assembly comprises the heating unit that is used for described catchment in addition, and the described polymer melt local heating of near thus small part is to being higher than T _MeltTemperature; Also comprise a plurality of embodiment preferred, for example wherein said heating unit comprises and extrudes the concentric well heater of aperture pattern; Wherein said heating unit is near described exit opening; Wherein said catchment comprise in addition with described passage concentric and with insulating material to described heating unit of small part and described die head assembly adjacency; Wherein said catchment comprise in addition with described passage concentric and with to the described heating unit of small part in abutting connection with and at the insulating material of described exit opening place and described channels abut; Wherein said passage is normally columniform and have basically diameter uniformly from the described opening that is used to receive polymer melt to described exit opening; Wherein said mouth template comprises a plurality of described at least one passage; Wherein said mouth template is the monolithic mouth template; Wherein said mouth template comprises having upstream face and comprise first block of plate of described upstream and have the second block of plate and the described well heater of downstream face, and described first is connected by described at least one channel flow with second block of plate; Wherein said mouth template comprises a plurality of described at least one passage; Comprise that a plurality of described at least one passage flow by each of described at least one passage with second block of plate and to be connected with wherein said first; Wherein said mouth template comprises and is selected from brass, stainless steel and Inconel ^TMMaterial; But wherein said insulating material be selected from high temperature plastics mechanical workout pottery, can be by sedimentary pottery of spraying technology and pottery that can be by the gas deposition deposition techniques; But wherein said insulating material be selected from high temperature plastics mechanical workout pottery, can be by sedimentary pottery of spraying technology and pottery that can be by the gas deposition deposition techniques; Wherein said second block of plate is the remodeling parts.

Another preferred embodiment of device comprises: be used for and will have the monolithic well heater of the resin forming equipment retrofit at least one extrusion die aperture, described well heater has first face and second face relative with described first face in described at least one the extrusion die aperture that is connected described resin forming equipment, between described first and second face and basically at least one passage that is complementary with described at least one extrusion die aperture, described thus aperture is connected with described channel flow and can will discharges the melting material heating in described at least one extrusion die aperture and the device of electric energy is provided to described monolithic well heater by the described passage of the described monolithic well heater of flowing through thus; And preferred embodiment is included in the insulating material on described second face; A plurality of described at least one passage; Wherein said heater material is selected from brass, stainless steel and Inconel ^TMBut wherein said insulating material be selected from high temperature plastics mechanical workout pottery, can be by sedimentary pottery of spraying technology and pottery that can be by the gas deposition deposition techniques; Wherein said well heater has the periphery of common circle and defines the central porisity of the internal diameter of described well heater usually, described well heater has a plurality of at least one passage, wherein between described first face and described second face with the thickness of well heater decrescence to reduce thickness gradually towards internal diameter.

Another embodiment preferred comprises the extrusion die assembly, described extrusion die assembly comprises having a plurality of extrusion die and aforesaid monolithic well heaters of extruding the aperture, described monolithic well heater has a plurality of apertures of extruding, and this is extruded a plurality of in aperture and the described extrusion die and extrudes the aperture and flow and be connected.

Claims (35)

1. one kind is used for the fluoropolymer resin process for granulating, this method comprises extrusion die assembly by comprising the die capillaries that at least one has the die head exit opening with the fluoropolymer resin melt extrusion, wherein with described die capillaries near the heating of die head exit opening portion so that the temperature of die head exit part is higher than the temperature of fluoropolymer resin melt.

2. the process of claim 1 wherein that the fluoropolymer resin melt comprises polyethylene.

3. according to the process of claim 1 wherein the high 30-170 of temperature ℃ of temperature ratio copolymer resin melt of die head exit part.

4. according to the process of claim 1 wherein that described fluoropolymer resin melt does not contain polymer processing aids.

5. according to the process of claim 1 wherein that described fluoropolymer resin melt comprises LLDPE, wherein said LLDPE has the melting index of measuring by ASTM method D-1238 that is less than or equal to 2.0dg/min.

6. according to the method for aforementioned claim 5, wherein said LLDPE has the melting index of measuring by ASTM method D-1228 that is less than or equal to 1.0dg/min.

7. according to the process of claim 1 wherein that described fluoropolymer resin melt comprises mLLDPE, wherein said mLLDPE has by ASTM method D-1238, the melting index that is less than or equal to 2.0dg/min that program B measures.

8. according to the method for claim 7, wherein said mLLDPE has the melting index of measuring by ASTM method D-1238, program B that is less than or equal to 1.0dg/min.

9. the moulded products of the resin that obtains of each a method that comprises by aforementioned claim, described moulded products does not have die head exit surface melt fracture basically.

10. the pellet of the resin that does not have die head exit surface melt fracture basically that obtains of a method that comprises by claim 1-8.

11. a mouth template, this mouth template comprises:

(a) upstream face;

(b) downstream face;

(c) but in described upstream face, have first opening that can receive molten resin and at least one passage that in described downstream face, has second opening of resin melt extrusion; With

(d) at described downstream opening place and the approaching well heater of described at least one passage.

12. according to the mouth template of claim 11, wherein said at least one passage is normally columniform and have basically a diameter uniformly from described upstream face to described downstream face.

13. according to the mouth template of claim 11, wherein said well heater is concentric with described at least one passage; Or wherein said at least one passage is by the described well heater of part, so that described part limits the wall near the described passage of described downstream face.

14. according to the mouth template of claim 11, this mouth template comprise in addition with described well heater and described mouth template in abutting connection with and with near near the concentric insulating material of described well heater described at least one passage of described downstream opening.

15. according to the mouth template of claim 11, this mouth template comprises in addition with concentric near described at least one passage of described downstream face and be formed up to the insulating material of the described downstream face of small part at described second opening part.

16. according to the mouth template of claim 11, this mouth template comprise in addition with described at least one passage concentric and with to the described heating unit of small part in abutting connection with and at the insulating material of described exit opening place and described at least one channels abut.

17. according to the mouth template of claim 11, but wherein said insulating material is selected from the pottery of high temperature plastics mechanical workout, by sedimentary pottery of spraying technology and the pottery by the gas deposition deposition techniques.

18. according to the mouth template of claim 11, wherein said mouth template is the monolithic mouth template.

19. according to the mouth template of claim 11, wherein said mouth template comprises first block of plate with described upstream face and have the second block of plate and the described well heater of described downstream face, described first is connected by described at least one channel flow with second block of plate.

20. according to the mouth template of claim 11, described mouth template comprises that a plurality of described at least one passage and wherein said first flow by each of described at least one passage with second block of plate and to be connected.

21. according to the mouth template of claim 11, wherein said mouth template comprises a plurality of described at least one passage.

22. according to each the mouth template of claim 11-21, wherein said mouth template is a metal.

23. according to each the mouth template of claim 11-21, wherein said mouth template comprises and is selected from brass, stainless steel and Inconel ^TMMaterial.

24. comprise each the extrusion die assembly of mouth template of claim 11-23, this assembly comprises at least one passage in addition, thereby described passage comprises the initial upstream that is made of the opening that is used to receive the polymer melt with body temperature T melt, is used to carry the intermediate zone of described polymer melt and stops the catchment that described extrusion die assembly discharged described polymer melt by described extrusion die assembly at the exit opening place.

25. the extrusion die assembly of claim 24, this assembly comprises the heating unit that is used for described catchment in addition, thus can the described polymer melt local heating of near small part to the temperature that is higher than the T melt.

26. according to the extrusion die assembly of claim 25, wherein said heating unit comprises and extrudes the concentric well heater of aperture pattern.

27. according to the extrusion die assembly of claim 25, wherein said heating unit is near described exit opening.

28. extrusion die assembly according to claim 24 or 25, wherein said catchment comprise in addition with described passage concentric and with to the described heating unit of small part and die head assembly or at the insulating material of the described channels abut at described exit opening place, wherein said passage is normally columniform.

29. the die head assembly of claim 28, wherein said passage has basically diameter uniformly from the described opening that is used to receive polymer melt to described exit opening.

30. each extrusion die assembly according to claim 24-27, wherein said mouth template comprises the first block of plate that has upstream face and comprise described upstream, second block of plate and the described well heater with downstream face, described first is connected by described at least one channel flow with second block of plate, and wherein said second block of plate is the remodeling parts.

31. according to the extrusion die assembly of claim 24, wherein said heating unit is to be used for and will to have the monolithic well heater of the resin forming equipment retrofit at least one extrusion die aperture; At least one passage that described well heater has first face in described at least one the extrusion die aperture that is connected described resin forming equipment, relative with described first face second face and is complementary between described first and second face and with described at least one extrusion die aperture; Described thus aperture is connected with described channel flow; Can will discharge the melting material heating in described at least one extrusion die aperture thus by the described passage of the described monolithic well heater of flowing through; Provide the device of electric energy to described monolithic well heater, and described a plurality of aperture of extruding is connected with a plurality of described at least one channel flow in the described monolithic well heater.

32. the extrusion die assembly of claim 31, wherein said monolithic well heater comprises described insulating material on described second face.

33. the extrusion die assembly of claim 32, wherein said monolithic well heater comprise a plurality of described at least one passage.

34. the extrusion die assembly of claim 33, described monolithic well heater comprises brass, stainless steel or Inconel ^TM

35. the extrusion die assembly of each of claim 32-34, wherein said monolithic well heater has the periphery of common circle and defines the central porisity of the internal diameter of described well heater usually, wherein between described first face and described second face with the thickness of well heater decrescence to reduce thickness gradually towards internal diameter.

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