WO2000022956A1

WO2000022956A1 - Utilization of biodegradable polyesters for producing bristles

Info

Publication number: WO2000022956A1
Application number: PCT/EP1999/007681
Authority: WO
Inventors: Uwe Witt; Gabriel Skupin; Günther WORF
Original assignee: Basf Aktiengesellschaft
Priority date: 1998-10-21
Filing date: 1999-10-13
Publication date: 2000-04-27
Also published as: DE19848505A1

Abstract

The invention relates to the utilization of biodegradable polyesters for producing bristles, and to bristles comprised of biodegradable polymers.

Description

_Before Using biodegradable polyester for producing bristles

description

The present invention relates to the use of biodegradable polyesters for the production of bristles. In addition, the invention relates to bristles made of biodegradable polyester.

It was known, for example from DE-Al 44 40 858, that biodegradable polyesters can be spun into threads or yarns and that these can in turn be processed into fibers.

Bristles such as used for brooms, brushes or brushes are traditionally made from animal hair such as horsehair or pig bristles. Pig bristle brushes have the disadvantage of losing their rigidity when they come into contact with water-based paints. Horsehair bristles are too soft for many applications. Another disadvantage of natural bristles is that the bristles are relatively difficult to attach to their respective carrier and run out during use. Bristles made of plastics, primarily polyamides or non-biodegradable polyesters such as polybutylene terephthalate have been developed. On the one hand, however, brooms, brushes or paintbrushes in the broadest sense belong to disposable products, so that these synthetic products are in need of improvement with regard to the environmental aspect. On the other hand, the known synthetic bristles can also be improved with regard to their usage properties, including the connection to the respective carrier.

The object of the present invention was therefore to provide a material for the production of bristles which enables the bristles to be connected as well as possible to the respective carrier and pollutes the environment as little as possible. Furthermore, the toughness and rigidity of the bristles thus obtained should be able to be adapted to the particular application. Bristles that are to be used for rinsing processes should absorb as little water as possible and be resistant to detergents. Another task was to provide bristles which have high tear and abrasion resistance, have good elastic recovery properties and have a good ability to straighten up after being subjected to buckling. The task is accomplished through the use of biodegradable polyesters to make bristles.

The polyesters which can be used according to the invention are biodegradable. In general, this means that the polyesters or the bristles produced therefrom disintegrate in a reasonable and demonstrable period of time. The degradation takes place, for example, hydrolytically and / or oxidatively, for the most part through the action of microorganisms such as bacteria, yeast, fungi and algae. Biodegradability can be determined, for example, by mixing samples with compost and storing them for a certain time. For example, compost ripened according to ASTM D 5338 is flowed through with composting with C0 ₂ -free air and subjected to a defined temperature program. The ratio of the net C0 ₂ release of the sample (after deducting the C0 release by the compost without sample) to the maximum C0 ₂ release of the sample (calculated from the carbon content of the sample) is defined as biodegradability. Bristles made from the biodegradable polyesters generally show clear signs of degradation, such as fungal growth, cracking and pitting, after only a few days of storage in the compost.

Polymeric reaction products of lactic acid can be used as biodegradable polymers according to the invention. These are known per se or can be produced by processes known per se. In addition to polylactide, copolymers or block copolymers based on lactic acid and other monomers can also be used. Linear polylactides are mostly used. However, branched lactic acid polymers can also be used. For example, multifunctional acids or alcohols can serve as branching agents. Polylactides can be mentioned by way of example, which essentially consist of lactic acid or its C 1 -C ₄ -alkyl esters or mixtures thereof and at least one aliphatic C ₄ - to Cio-dicarboxylic acid and at least one C ₃ - to Cir-alkanol with three to five Hydroxy groups are available.

Examples of biodegradable polymers from which the bristles can be obtained are also aliphatic polyesters. These include homopolymers of aliphatic hydroxycarboxylic acids or lactones but also copolymers or block copolymers of different hydroxycarboxylic acids or lactones or mixtures thereof. These aliphatic polyesters can also contain diols and / or isocyanates as building blocks. In addition, the aliphatic polyesters can also contain building blocks that differ from trifunctional or multifunctional compounds such as epoxides, acids or

Derive triplets. The latter blocks can be individually or can several of them or together with the diols and / or isocyanates can be contained in the aliphatic polyesters.

Methods for producing aliphatic polyesters are known to the person skilled in the art. The aliphatic polyesters generally have molecular weights (number average) in the range from 10,000 to 100,000 g / mol.

Polycaprolactone is one of the particularly preferred aliphatic polyesters.

Poly-3-hydroxybutanoic acid esters and copolymers of 3-hydroxybutanoic acid or their mixtures with 4-hydroxybutanoic acid and 3-hydroxyvaleric acid, in particular a weight fraction of up to 30, preferably up to 20,% by weight of the latter acid are particularly preferred aliphatic polyester. Suitable polymers of this type also include those with an R-stereospecific configuration as known from WO 96/09402. Polyhydroxybutanoic acid esters or their copolymers can be produced microbially. Methods for the production from various bacteria and fungi are e.g. Chem Tech. Lab. 39, 1112-1124 (1991), a method for producing sterospecific polymers is known from WO 96/09402.

In addition, block copolymers from the named

Hydroxycarboxylic acids or lactones, their mixtures, oligomers or polymers are used.

Further aliphatic polyesters are those which are composed of aliphatic or cycloaliphatic dicarboxylic acids or their mixtures and aliphatic or cycloaliphatic diols or their mixtures. According to the invention, both statistical and block copolymers can be used.

The aliphatic dicarboxylic acids suitable according to the invention generally have 2 to 10 carbon atoms, preferably 4 to 6 carbon atoms. They can be both linear and branched. The cycloaliphatic dicarboxylic acids which can be used in the context of the present invention are generally those having 7 to 10 carbon atoms and in particular those having 8 carbon atoms. In principle, however, dicarboxylic acids with a larger number of carbon atoms, for example with up to 30 carbon atoms, can also be used.

Examples include: malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, acelaic acid, sebacic acid, fumaric acid, 2, 2-dimethylglutaric acid, suberic acid, 1,3-cyclo- pentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, diglycolic acid, itaconic acid, maleic acid and 2,5-norbornanedicarboxylic acid, among which adipic acid is preferred.

The ester-forming derivatives of the abovementioned aliphatic or cycloaliphatic dicarboxylic acids, which can also be used, are in particular the di-Ci to Cδ-alkyl esters, such as methyl, diethyl, di-n-propyl, di-isopropyl, di-n-butyl , Di-iso-butyl, di-t-butyl, di-n-pentyl, di-iso-pentyl or di-n-hexyl esters. Anhydrides of the dicarboxylic acids can also be used.

The dicarboxylic acids or their ester-forming derivatives can be used individually or as a mixture of two or more thereof.

Examples of the suitable aliphatic polyesters are aliphatic copolyesters as described in WO 94/14870, in particular aliphatic copolyesters from succinic acid, its diesters or their mixtures with other aliphatic acids or diesters such as glutaric acid and butanediol or mixtures of this diol with ethylene glycol , Propanediol or hexanediol or mixtures thereof.

Aliphatic polyesters of this type generally have molecular weights (number average) in the range from 10,000 to 100,000 g / mol.

Likewise, the aliphatic polyesters can be statistical or

Block copolyesters that contain other monomers. The proportion of the other monomers is usually up to 10% by weight. Preferred comonomers are hydroxcarboxylic acids or lactones or mixtures thereof.

Mixtures of two or more comonomers and / or further building blocks, such as epoxides or polyfunctional aliphatic or aromatic acids or polyfunctional alcohols, can of course also be used to prepare the aliphatic polyesters.

Partially aromatic polyesters are particularly preferably used for the production of the bristles. According to the invention, this also includes polyester derivatives such as polyether esters, polyester amides or polyether ester amides. Suitable biodegradable partially aromatic polyesters include linear non-chain extended polyesters (WO 92/09654). To be favoured chain-extended and / or branched partially aromatic polyesters. The latter are known from the documents mentioned at the outset, WO 96/15173 to 15176, 21689 to 21692, 25446, 25448 or WO 98/12242, to which reference is expressly made. Mixtures of different partially aromatic polyesters are also possible, as are blends of partially aromatic polyesters.

The particularly preferred partially aromatic polyesters include polyesters, which are essential components

A) an acid component

al) 30 to 95 mol% of at least one aliphatic or at least one cycloaliphatic dicarboxylic acid or its ester-forming derivatives or mixtures thereof

a2) 5 to 70 mol% of at least one aromatic dicarboxylic acid or its ester-forming derivative or mixtures thereof and

a3) 0 to 5 mol% of a compound containing sulfonate groups,

B) a diol component selected from at least one C ₂ bis

Cι_-alkanediol and at least one C5 to Cio-cycloalkanediol or mixtures thereof

and, if desired, furthermore one or more components selected from

C) a component selected from

cl) at least one dihydroxy compound of the formula I containing ether functions

HO - [(CH ₂ ) _n -0] _m -H (I)

where n is 2, 3 or 4 and m is an integer from 2 to 250

c2) at least one hydroxycarboxylic acid or formula Ha or Ilb

HO- [C (O) G 0—] _p HI— [-c (o) G 0—] _r -

(Ila) (Ilb) where p is an integer from 1 to 1500 and r is an integer

Number from 1 to 4, and G represents a radical which is selected from the group consisting of phenylene,

- (CH) _q -, where q is an integer from 1 to 5, -C (R) H- and -C (R) HCH ₂ , where R is methyl or ethyl

c3) at least one amino-C - to Cχ -alkanol or at least one amino-Cs to Cιo ~ cycloalkanol or mixtures thereof

c4) at least one diamino-Cχ to Cg alkane

c5) at least one 2, 2 'bisoxazoline of the general formula III

where R ^{1 is} a single bond, a (CH) _Z alkylene group, with z = 2, 3 or 4, or a phenylene group

c6) at least one aminocarboxylic acid selected from the

Group consisting of the natural amino acids, polyamides with a molecular weight of at most 18000 g / mol, available through polycondensation of a dicarboxylic acid with 4 to 6 C atoms and a diamine with 4 to 10 C atoms, compounds of the formulas IV a and IVb

HO- [-C (O) -TN (H) -] _S H ^L [-C (0) -TN (H) -] _t ^J (iva) _(ιvb)

in which s is an integer from 1 to 1500 and t is an integer from 1 to 4, and T is a radical which is selected from the group consisting of phenylene, - (CH ₂ ) _n -, where n is an integer Number from 1 to 12 denotes -C (R ² ) H- and -C (R ² ) HCH ₂ , where R ^{2 represents} methyl or ethyl,

and polyoxazolines with the repeating unit V

in which R ^{3 represents} hydrogen, C ₁ -C ₆ -alkyl, C ₅ -C ₈ cycloalkyl, unsubstituted or with C 1 -C 4 -alkyl groups up to triple-substituted phenyl or tetrahydrofuryl,

or mixtures of cl to c6

and

D) a component selected from

dl) at least one compound with at least three groups capable of ester formation,

d2) at least one isocyanate

d3) at least one divinyl ether

or mixtures of dl) to d3).

The acid component A of the preferred partially aromatic polyesters contains from 30 to 70, in particular from 40 to 60, mol% al and from 30 to 70, in particular from 40 to 60 mol% a2.

The aliphatic or cycloaliphatic acids and the corresponding derivatives al are those mentioned above. Adipic acid or sebacic acid or their respective ester-forming derivatives or mixtures thereof are particularly preferably used. Adipic acid or its ester-forming derivatives, such as its alkyl esters or mixtures thereof, are particularly preferably used.

Aromatic dicarboxylic acid a2 generally includes those with 8 to 12 carbon atoms and preferably those with 8 carbon atoms. Examples include terephthalic acid, isophthalic acid, 2, 6-naphthoic acid and 1, 5-naphthoic acid and ester-forming derivatives thereof. In particular, the di-C ₆ alkyl esters, for example dimethyl, diethyl, di-n-propyl, di-iso-propyl, di-n-butyl, di-isobutyl, di-t- butyl, di-n-pentyl, di-iso-pentyl or di-n-hexyl esters. The anhydrides of dicarboxylic acids a2 are also suitable ester-forming derivatives. In principle, however, aromatic dicarboxylic acids a2 with a larger number of carbon atoms, for example up to

20 carbon atoms can be used.

The aromatic dicarboxylic acids or their ester-forming derivatives a2 can be used individually or as a mixture of two or more thereof. Terephthalic acid or its ester-forming derivatives such as dimethyl terephthalate are particularly preferably used.

The sulfonate group-containing compound used is usually an alkali metal or alkaline earth metal salt of a sulfonate group-containing dicarboxylic acid or its ester-forming derivatives, preferably alkali metal salts of 5-sulphoisophthalic acid or mixtures thereof, particularly preferably the sodium salt.

According to one of the preferred embodiments, the acid component A contains from 40 to 60 mol% a1, from 40 to 60 mol% a2 and from 0 to 2 mol% a3. According to a further preferred embodiment, the acid component A contains from 40 to 59.9 mol% of al, from 40 to 59.9 mol% of a2 and from 0.1 to 1 mol% of a3, in particular from 40 to 59.8 mol% % al, from 40 to 59.8 mol% a2 and from 0.2 to 0.5 mol% a3.

In general, the diols B are selected from branched or linear alkane diols having 2 to 12 carbon atoms, preferably 4 to 6 carbon atoms, or cycloalkane diols having 5 to 10 carbon atoms.

Examples of suitable alkanediols are ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,5-pentanediol, 2,4-dimethyl-2-ethylhexane 1,3-diol, 2,2-dimethyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 2-ethyl-2-isobutyl-1,3-propanediol, 2, 2,4-trimethyl-1,6-hexanediol, in particular ethylene glycol, 1,3-propanediol, 1,4-butanediol and 2,2-dimethyl-1,3-propanediol (neopentyl glycol); Cyclopentanediol, 1,4-cyclohexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol or 2,2,4,4-tetramethyl-l, 3-cyclobutanediol. Mixtures of different alkanediols can also be used.

Depending on whether an excess of acid or OH end groups is desired, either component A or component B can be used in excess. According to a preferred embodiment, the molar ratio of the components A to B used can be in the range from 0.4: 1 to 1.5: 1, preferably in the range from 0.6: 1 to 1.1: 1. In addition to components A and B, the polyester from which the

Bristles are made to contain other components.

The dihydroxy compounds cl used are preferably diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol and polytetrahydrofuran (poly-THF), particularly preferably diethylene glycol, triethylene glycol and polyethylene glycol, mixtures of these or compounds having different variables n also being used (see formula I ), for example polyethylene glycol, which contains propylene units (n = 3), for example obtainable by polymerization according to known methods of first ethylene oxide and then with propylene oxide, particularly preferably a polymer based on polyethylene glycol, with different variables n, units being formed predominate from ethylene oxide. The molecular weight (M _n ) of the polyethylene glycol is generally chosen in the range from 250 to 8000, preferably from 600 to 3000 g / mol.

According to one of the preferred embodiments, for example from 15 to 98, preferably 60 to 99.5 mol% of the diols B and 0.2 to 85, preferably 0.5 to 30 mol% of the dihydroxy compounds cl, based on the molar amount of B and cl, can be used for the production of the partially aromatic polyester.

In a preferred embodiment, the hydroxycarbonic acid c2) used is: glycolic acid, D-, L-, D-, L-lactic acid, 6-hydroxyhexanoic acid, their cyclic derivatives such as glycolide (1,4-dioxane-2,5- dione), D-, L-dilactide (3, 6-dimethyl-l, 4-dioxan-2, 5-dione), p-hydroxybenzoic acid as well as their oligomers and polymers such as 3-polyhydroxybutyric acid, polyhydroxyvaleric acid, polylactide (for example, as EcoPLA ^® (Fa. Cargill)), or a mixture of 3-polyhydroxybutyric acid and polyhydroxyvaleric acid (the latter is under the name Biopol ^® by Zeneca), particularly preferred for the preparation of partially aromatic polyester low molecular weight and cyclic derivatives thereof.

The hydroxycarboxylic acids can be used, for example, in amounts of from 0.01 to 50, preferably from 0.1 to 40,% by weight, based on the amount of A and B.

As amino-C ₂ -C ₂ -alkanol or amino-Cs-Cio-cyloalkanol (component c3), which should also include 4-aminomethylcyclohexane-methanol, preference is given to amino-C-C6-alkanols such as 2-aminoethanol, 3-aminopropanol , 4-aminobutanol, 5-aminopentanol, 6-aminohexanol and amino-C ₅ -C ₆ -cycloalkanols such as aminocyclopentanol and aminocyclohexanol or mixtures thereof.

The diamino-Ci-Cs-alkane (component c4) used is preferably diamino-5 no-C ₄ -C ₆ -alkane such as 1,4-diminobutane, 1,5-diaminopentane and 1,6-diaminohexane (hexamethylenediamine, " HMD ").

According to a preferred embodiment, from 0.5 to 99.5, preferably from 70 to 98.0 mol% of the diol component B, 0.5 to 10 99.5, preferably 0.5 to 50 mol% c3 and from 0 to 50 , preferably from 0 to 35 mol% c4, based on the molar amount of B, c3 and c4, can be used for the preparation of the partially aromatic polyesters.

15 The 2, 2 'bisoxazolines c5 of the general formula III are generally obtainable by the process from Angew. Chem. Int. Edit., Vol. 11 (1972), pp. 287-288. Particularly preferred bisoxazolines are those in which R ^{1 is} a single bond, a (CH ₂ ) _q alkylene group with q = ₂ , 3 or 4, such as methylene,

20 is ethane-1,2-diyl, propane-1,3-diyl, propane-1,2-diyl, or a phenylene group. Particularly preferred bisoxazolines are 2, 2'-bis (2-oxazoline), bis (2-oxazolinyl) methane, 1, 2-bis (2-oxazolinyl) ethane, 1, 3-bis (2-oxazolinyDpropane or 1, 4 Bis (2-oxazolinyl) butane, in particular 1,4-bis (2-oxazoli-

25 called nyDbenzene, 1, 2-bis (2-oxazolinyl) benzene or 1, 3-bis (2-oxazoli - nyDbenzene.

The partially aromatic polyesters can be produced, for example, from 70 to 98 mol% of Bl to 30 mol% of c3 and 0.5 to 30 mol% of c4

30 and 0.5 to 30 mol% c5, based in each case on the sum of the molar amounts of the components B1, c3, c4 and c5, can be used. According to another preferred embodiment, it is possible to use from 0.1 to 5, preferably 0.2 to 4% by weight of c5, based on the total weight of A and B.

35

Natural aminocarboxylic acids can be used as component c6. These include valine, leucine, isoleucine, threonine, methionine, phenylalanine, tryptophan, lysine, alanine, arginine, aspartic acid, cysteine, glutamic acid, glycine, histidine, proline,

40 serine, tryosine, asparagine or glutamine.

Preferred aminocarboxylic acids of the general formulas IVa and IVb are those in which s is an integer from 1 to 1000 and t is an integer from 1 to 4, preferably 1 or 2 and T is selected from the group phenylene and - (CH ₂ ) _n -, where n is 1, 5 or 12. Furthermore, c6 can also be a polyoxazoline of the general formula V. C6 can also be a mixture of different aminocarboxylic acids and / or polyoxazolines.

According to a preferred embodiment, c6 can be used in amounts of 0.01 to 50, preferably 0.1 to 40% by weight, based on the total amount of components A and B.

Other components that can optionally be used to produce the partially aromatic polyesters include

Compounds dl which contain at least three groups capable of ester formation.

The compounds dl preferably contain three to ten functional groups which are capable of forming ester bonds. Particularly preferred compounds dl have three to six functional groups of this type in the molecule, in particular three to six hydroxyl groups and / or carboxyl groups. Examples include:

Tartaric acid, citric acid, malic acid;

Trimethylolpropane, trimethylolethane;

Pentaerythritol;

Polyether triols; Glycerin;

Trimesic acid;

Trimellitic acid, anhydride;

Pyromellitic acid, dianhydride and

Hydroxyisophthalic acid.

The compounds dl are generally used in amounts of 0.01 to 5, preferably 0.05 to 4 mol%, based on component A.

One or a mixture of different isocyanates is used as component d2. For example, aromatic or aliphatic diisocyanates can be used. However, higher functional isocyanates can also be used.

In the context of the present invention, an aromatic diisocyanate d2 is primarily

Toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, naphthylene-1, 5-diisocyanate or xylylene diisocyanate. Among them, 2,2'-, 2,4'- and 4,4'-diphenylmethane diisocyanate are particularly preferred as component d2. In general, the latter diisocyanates are used as a mixture.

Tri (4-isocyanophenyD-methane) can also be used as the trinuclear isocyanate d2. The multinuclear aromatic diisocyanates are obtained, for example, from the production of mono- or dinuclear diisocyanates.

In minor quantities, e.g. Up to 5% by weight, based on the total weight of component d2, component d2 can also contain urethione groups, for example for capping the isocyanate groups.

The preferred isocyanurates include the aliphatic isocyanurates, such as isocyanurates, which are derived from alkylene diisocyanates or cycloalkylene diisocyanates having 2 to 20 carbon atoms, preferably 3 to 12 carbon atoms, e.g. Isophorone diisocyanate. The alkylene diisocyanates can be linear or branched. Diisocyanurates based on n-hexamethylene diisocyanate are particularly preferred.

In general, component d2 is used in amounts of 0.01 to 5, preferably 0.05 to 4, mol%, based on the sum of the molar amounts of A and B.

In general, all customary and commercially available divinyl ethers can be used as the divinyl ether d3. 1,4-butanediol divinyl ether, 1,6-hexanediol divinyl ether or 1,4-cyclohexanedimethanol divinyl ether or mixtures thereof are preferably used.

The divinyl ethers are preferably used in amounts of from 0.01 to 5, in particular from 0.2 to 4, by weight, based on the total weight of A and B.

Examples of preferred partially aromatic polyesters are based on the following components

A, B, dl

A, B, d2

A, B, dl, d2

A, B, d3

A, B, cl A, B, cl, d3

A, B, c3, c4

A, B, c3, c4, c5 A, B, dl, c3, c5

A, B, c3, d3

A, B, c3, dl

A, B, cl, c3, d3 A, B, c2

These include partially aromatic polyesters based on A, B, dl or A,

B, d2 or based on A, B, dl, d2, particularly preferred. According to another preferred embodiment, the partially aromatic polyesters are based on A, B, c3, c4, c5 or A, B, dl, c3, c5.

The production of the partially aromatic polyesters is known per se or can be carried out according to methods known per se.

The preferred partially aromatic polyesters are characterized by a molecular weight (Mn) in the range from 5000 to 50,000, in particular in the range from 10,000 to 40,000 g / mol, with a viscosity number in the range from 50 to 400, in particular in the range from 100 to 300 g / ml (measured in o-dichlorobenzene / phenol; weight ratio 50/50, at a concentration of 0.5% by weight polymer and a temperature of 25 ° C.) and a melting point in the range from 60 to 170, preferably in the range from 80 to 150 ° C.

The biodegradable polymers can contain additives which can be incorporated in any stage or subsequently, for example into a melt of the biodegradable polymers, during the polymerization process. Stabilizers, neutralizing agents, lubricants and release agents, e.g. Erucic acid amide or beeswax, antiblocking agents such as silicon dioxide, chalk or talc, preferably called fine talc, nucleating agents, dyes or fillers.

Based on the biodegradable polymers, from 0 to 80% by weight of additives can be added. Suitable additives are, for example, carbon black, lignin powder, iron oxides, clay minerals, ores, calcium carbonate, calcium sulfate, barium sulfate and titanium dioxide, stabilizers such as tocopherol (vitamin E), organic phosphorus compounds, mono-, di- and polyphenols, hydroquinones, diarylamines , Thioether. Talc, for example, can be used as the nucleating agent. Lubricants and mold release agents based on hydrocarbons, fatty alcohols, higher carboxylic acids, metal salts of higher carboxylic acids such as calcium or zinc stearate, or montan waxes could also be included as additives. Such stabilizers etc. are described in detail in Kunststoff-Handbuch, Vol. 3/1, Carl Hanser Verlag, Munich, 1992, pp. 24 to 28. In principle, bristles of various lengths and thicknesses can be made from the biodegradable polymers. In general, however, the bristles according to the invention have a thickness of 0.001 to 5 mm, for example 0.005 to 4 mm, preferably 0.01 to 3 mm. As a rule, the bristles are no longer than about 20 cm, preferably no longer than 15 cm. Depending on the field of application, the bristles can be very short, for example up to 1 or 0.5 cm or even shorter.

The bristles according to the invention can have a round profile, but can also be flattened, for example. The cross section of the bristles can be made uniform. However, it is also possible for the bristles to have a tapering cross section. Bristles according to the invention can have a full profile or be hollow, for example have a trilobal or quadrilobal cross section.

The production of bristles from plastics is a generally known process. For example, the bristles can be produced from the granulate. However, they can also be produced directly from the polycondensation melt. For the production of the bristles from solid form, the biodegradable polymers are first melted in suitable units like a screw press. The melt is then conveyed over conveyor elements that ensure the most uniform possible transport, e.g. a gear or measuring pump conveyed to the spinning device. Overpressure can be applied at the same time. A sieve filter can be connected upstream of the spinning device. As a rule, the spinning device contains at least one spinneret plate with bores, the width of which corresponds to the desired bristle diameter. The bristle strands are then cooled, for example by ambient air, an air shower and / or water. Depending on the cooling temperature, the cross section of the bristles or the crystallization of the biodegradable polyester can be influenced. If one starts directly from the melt, there is no melting process. It may be necessary to later extract the low molecular weight portions from the bristle strands.

In order to increase the properties of the bristles, in particular the tensile strength and the service life, the bristle strands are generally stretched before they are divided into the desired length.

As a rule, the biodegradable polymers are stretched above the glass transition temperature or below their crystallite melting temperatures. In a preferred embodiment is stretched at temperatures in the range from 0 to 100, in particular from 5 to 95 ° C. The stretching process can be carried out in one or more steps.

This can be achieved, for example, by guiding over two, three, five or more rollers with different speeds of rotation. The ratio of the take-off speeds of the last to the first pair of rollers indicates the degree of longitudinal orientation.

In order to achieve good stretchability and reproducible caliber accuracy (diameter accuracy), however, it is advantageous to cool the bristle strands after the molten discharge from the extruder nozzle in a first stage to temperatures of 0 to 25 ° C., preferably 3 to 10 ° C. then heat in a second stage to temperatures of 30 to 95 ° C, preferably 50 to 80 ° C and then stretch.

After stretching, the bristle strands can be heat-set with heated rollers or with hot air (approx. 75 to 150 ° C, preferably 100 to 120 ° C). For this purpose, the bristle strands are guided, for example, via rollers through a closed container with a temperature-controlled air flow or steam flow. The residence time is usually 1 to 20 s, preferably 2 to 5 s.

After the stretching process, the bristles can be surface-treated using standard methods. The polarity of the surface can be changed by corona, flame or plasma treatment or treatment with oxidative, deposits or deposits, so that the bristles can adhere more or less to surfaces, for example.

In general, the surface of the bristles is very smooth without pretreatment.

The softness of the bristles can be influenced on the one hand by the structure of the underlying biodegradable polymers, on the other hand it is possible to use soft bristles by adding waxes, e.g. Beeswax.

The bristles according to the invention are particularly suitable for the production of articles which contain bristles and which are thrown away after use or whose bristle carrier is replaced. The bristles according to the invention can be in the form of hygiene articles such as toothbrushes, hand brushes, hairbrushes, massage brushes, nail polish brushes, toilet brushes or for rinsing processes such as rinsing brushes in the household and in industry such as for washing systems for beer, juice, mineral water, milk or yoghurt glasses, for other sti e _g _R agreement brushes such as shoe shine brushes, scrubbers, Kehrbe ^¬ sen, vacuum cleaner brushes, cleaning brushes, brush dust but also for other nwendungszwecke _A in the form of brushes or wallpaper Pin ^¬ sel for painting or artist needs to be used.

_A variety of plastics or wood can be used as a carrier for the bristles. According to a particularly preferred embodiment, the entire article can be made up of biodegradable polymers.

The bristles according to the invention are characterized in that they are biodegradable. Furthermore, their hardness is adjustable. They have high tensile strengths and have a low tendency to splice. They can be connected very well, preferably by gluing at elevated temperatures to a carrier, in particular a plastic carrier.

Examples

(Mol - _{ra tio} 45:55) for the manufacture of bristles according to the invention, a partially aromatic polyester of terephthalic acid, adipic acid, butanediol, hexamethylene diisocyanate and glycerol rin having a melt volume index MVI of 5.5 cm ^3/10 '(measured according to ISO 1133 , at 190 ° C and a load of 2.16 kg).

_T he polyester was melted in the extruder and mixed with the ABLE in the _T 1 stated amounts of erucic acid amide and Feintalkum ge ^¬. The melt was discharged through a nozzle at a melt temperature of 195 ° C. and cooled in a water bath. Closing at ^¬ the residual water of the bristle strands was vacuum ^¬ ent removed and the bristle strands set by slightly different rolling speeds under tension. The bristle strands were stretched 1: 4 at a temperature of 90 ° C. and then relaxed at 120 ° C., showing a shrinkage of 7%. The bristle strands were individually wound on a winding system and processed into bristles on separate systems.

Table 1

Application technical tests

1. Recuperation

5 The recovery ability was checked with the aid of a kink test in which the bristles were loaded in a testing device for a defined period of 5 minutes. The test device consists of a hook, weighing 181 g, on two linked loops from the bristle batch to be tested

10 (0.3 mm nominal diameter) were hung. The loops were then cut open to check the ability to recover and left to hang for a further 10 minutes. The loops were then placed on a plate and measured with a protractor. The remaining opening angle of the loop is a measure of the

15 ability of the material. Each test was carried out ten times.

For comparison, bristles made of polyamide from different manufacturers and different compositions (PA66, PA 610, PA 20 612) were measured. The recovery capacity of a polybutylene terephthalate (PBT) was also determined. The values typically achieved for polyethylene terephthalate bristles (PET) and bristles made of polypropylene (PP) are also shown in Table 2.

25 Table 2

Bristle material recovery (dry) for comparison:

30 PA 66 145.3 ° - 150.2 ° a ⁾

PA 610 145.3 °

PA 612 143.3 °

PBT 139.4 °

PET 90 ° ^b >

35

PP 90 ° ^b > according to the invention:

1 145.3 °

2 112.5 °

40 ^a > Five different types of PA 66 were examined. ^B) Typical value

As can be seen from Table 2, the values found ₄₅ with a low talcum content for the bristles according to the invention are in the range of polyamide. The recovery ability is adjustable and If the talc content is higher than that typically found for polyethylene terephthalate or polypropylene.

2. Flexural rigidity

The bending stiffness was determined with a bending stiffness tester from Lorenzen-Wettre. One clamped bristle is moved against a measuring head, which measures the counterforce at a deformation angle of 30 °. From this, the bending stress is calculated over the diameter, which is proportional to the bending stiffness. Each test was carried out 10 times.

Table 3

As can be seen from Table 3, the bristles according to the invention made of materials 1 and 2 are soft.

Claims

claims

1. Use of biodegradable polyester for the production of bristles.

2. Use according to claim 1, in which the biodegradable polyesters are partially aromatic polyesters containing as essential components

A) an acid component

a3) 0 to 5 mol% of a compound containing sulfonate groups,

B) a diol component selected from at least one C ₂ -C 1 -alkanediol and at least one C ₅ -Cirj-cycloalkanediol or mixtures thereof

and, if desired, one or more components selected from

C) a component selected from

cl) at least one dihydroxy compound of the formula I containing ether functions

HO - [(CH ₂ ) _n -0] _m -H (I)

in which n is 2, 3 or 4 and m is an integer from 2 to 250,

c2) at least one hydroxycarboxylic acid or formula Ha or Ilb HO— [C (0) G 0— _H [-C (O) G 0—]

[Ha) (Ilb) in which p is an integer from 1 to 1500 and r is an integer from 1 to 4, and G represents a radical which is selected from the group consisting of phenylene, - (CH) _q - , where q is an integer from 1 to 5, -C (R) H- and -C (R) HCH ₂ , where R is methyl or ethyl

c3) at least one amino-C - to -CC alkanol or at least one amino-Cs to Cio-cycloalkanol or mixtures thereof

c4) at least one diamino-Cχ to C ₈ alkane

c5) at least one 2, 2 'bisoxazoline of the general formula III

where R ^{1 is} a single bond, a (CH ₂ ) _Z alkylene group, with z = 2, 3 or 4, or a phenylene group

c6) at least one aminocarboxylic acid selected from the group consisting of the natural amino acids, polyamides with a molecular weight of at most 18000 g / mol, obtainable by polycondensation of a dicarboxylic acid with 4 to 6 C atoms and a diamine with 4 to 10 C atoms, compounds of the formulas IV a and IVb

HO- [-C (O) -TN (H) -] _S H ltC (O) -TN (H) -] _t -l

< ^IVa > (IVb)

in which s is an integer from 1 to 1500 and t is an integer from 1 to 4, and T is a radical which is selected from the group consisting of phenylene, - (CH) _n -, where n is an integer from 1 to 12 means -C (R ² ) H- and -C (R ² ) HCH ₂ , where R ^{2 is} methyl or ethyl,

and polyoxazolines with the repeating unit V

in which R ^{3 represents} hydrogen, C ₁ -C ₆ -alkyl, C ₅ -C ₈ cycloalkyl, unsubstituted or with C 1 -C ₄ -alkyl groups up to triply substituted phenyl or tetrahydrofuryl,

or mixtures of cl) to c6)

and

D) a component selected from

d2) at least one isocyanate

d3) at least one divinyl ether

or mixtures of dl) to d3).

3. Use according to claim 1 or 2, in which the biodegradable polyesters are partially aromatic polyesters based on the components A, B and dl or A, B and d2 or A, B, Dl and d2 or A, B, c3, c4 and c5 or A, B, dl, c3 and c5 based.

4. Use according to claims 1 to 3 for the production of bristles with a thickness in the range of 0.001 to 3 mm.

5. Bristles, available from biodegradable polyesters.

6. bristles for hygiene articles according to claim 5.

7. bristles for cleaning brushes according to claim 5.

8. bristles for brushes according to claim 5.

9. bristles for rinsing according to claim 5.

10. bristles for wallpaper brushes according to claim 5.