WO2007060470A1 - Comminutable polyesters - Google Patents
Comminutable polyesters Download PDFInfo
- Publication number
- WO2007060470A1 WO2007060470A1 PCT/GB2006/004432 GB2006004432W WO2007060470A1 WO 2007060470 A1 WO2007060470 A1 WO 2007060470A1 GB 2006004432 W GB2006004432 W GB 2006004432W WO 2007060470 A1 WO2007060470 A1 WO 2007060470A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- polyester
- process according
- acid
- comminutable
- treatment
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B9/00—Making granules
- B29B9/12—Making granules characterised by structure or composition
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
- C08G63/91—Polymers modified by chemical after-treatment
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/12—Powdering or granulating
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/28—Treatment by wave energy or particle radiation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
- C08J7/12—Chemical modification
- C08J7/123—Treatment by wave energy or particle radiation
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
Definitions
- polyesters There are numerous existing and potential applications for powders of polyesters.
- oil industry applications include acidizing, acid fracturing of oil and gas wells, use as components of drilling muds or drill-in fluids, diverting or fluid loss agents, as breakers for cross-linked stiff or rigid gels for temporary blocking, as breakers for fracturing gels, or agents for the carriage and controlled release or delivery of a range of well or formation treatment chemicals.
- polyester powders as components of drug or pharmaceutical delivery agents or preparations, as components of biocompatible or biodegradable scaffolds including porous or sintered scaffolds suitable for use in tissue growth or repair processes e.g. bone or skin growth or repair.
- Polyester powders may also be useful as carriers or agents for the controlled rate delivery of many types of chemicals in numerous other industrial applications.
- the chemicals may include vetinary pharmaceuticals; agrochemicals including plant growth regulators; nutrients such as fertilizers, micronutrients or minerals; biocides such as bactericides, viricides, fungicides, insecticides, algicides, molluscides or herbicides; pH adjusting agents; dyes, fragrances; pigments, including pigments used in toners or components of cleaning preparations in applications including, for example, agricultural, (e.g. silage, animal husbandry) effluent treatment, environmental, gardening, laundry, food or household applications.
- agricultural, (e.g. silage, animal husbandry) effluent treatment environmental, gardening, laundry, food or household applications.
- Polyester powders may also be used directly in artificial latex, as coatings (for example paper) as binders, as mild abrasives, as paint additives, in adhesives or for powder coating applications.
- polyester powders may be used in composite materials, packaging materials or energy absorbing materials.
- polyesters for example those produced from lactic acid, glycolic acid, lactide, glycolide, hydroxybutyric acid (such as polylactide, polyglycolide, polyhydroxybutyric acid) or water soluble copolymers.
- a number of these polyesters are particularly suited for use in oil industry applications and other industrial applications where their biocompatibility, high environmental acceptability, and predictable rate of dissolution and acid production give an advantage. In addition they may be produced from renewable resources.
- a number of methods are available for producing powders of polyesters. These include conventional grinding, solvent based methods such as dissolving the polyester in a solvent followed by spray drying, emulsion polymerisation or dispersion of a polymer melt.
- polyesters are only soluble in a limited range of solvents which may not be particularly acceptable from an operational, environmental or health and safety point of view.
- solvents mostly chlorinated hydrocarbons. Traces of solvent up to a few percent w/w may remain in the powder, even after drying, and this is highly undesirable.
- Emulsion polymerisation or dispersion of a polymer melt require careful process control and may be energy intensive. Dispersion methods may leave high concentrations of surfactant in the product, which is again undesirable.
- polyesters including those that would otherwise be suitable for oilfield applications, are not readily comminutable by conventional grinding or similar processes, even using cryogenic grinding, in part due to their low glass transition temperature (Tg). It is currently difficult or impossible to produce large amounts of powder from such polyesters at an acceptable cost via grinding type methods.
- Tg glass transition temperature
- polyester powders Although the use of polyester powders has been taught for a number of oilfield applications, details of how to produce polyester-only powders by grinding type methods have not been disclosed and such powders do not appear to be commercially available.
- EP 0311564 discloses that powders may be produced from a polyester that is mixed and co-extruded with a suitable filler, such as calcium carbonate, which presumably alters the material's characteristics allowing grinding. Obviously, particles produced by such a method comprise a mixture of polyester and filler in the same particle.
- US 4,986,355 teaches a process of preparing suitably sized polyester particles for use as a fluid loss additive or as a gel breaker in a subterranean formation by dispersion of a polymer melt.
- polyester powders particularly powders of water soluble polyesters such as polylactides, polyglycolides, polyhydroxybutyric acid, copolymers and the like, which are suitable for use in oilfield and other applications, may be produced by standard comminution methods such as grinding and which can be readily scaled-up.
- a further object is to provide a process for producing polyester powders that are free of contaminants such as solvents and surfactants.
- An additional object is to provide a process for producing a polyester powder from commercially available polyester resins.
- the present invention provides a process for producing a polyester in powder form, which process comprises:
- step (a) rendering a polyester comminutable by (i) chemical pre-treatment of the polyester, or (ii) irradiating the polyester; and (b) comminuting the polyester produced in step (a) to form a powder.
- the invention also provides a process for producing a polyester in powder form, which process comprises:
- step (b) comminuting the polyester produced in step (a) to form a powder.
- the process of the present invention may be applied to those families of polyesters that are not readily comminutable, such as polylactic acid, polyglycolic acid, polylactides, polyglycolides and their copolymers, including copolymers with caprolactone.
- the polyesters may be rendered comminutable by either pre-treatment of the polyester by irradiation or by a chemical pre-treatment. Generally it will be desirable to irradiate or chemically pre-treat a commercially available polyester resin.
- the introduction of such covalent branch points may be by the incorporation into the polymer of non-ester monomeric units, such as compounds of the type described herein, giving rise to a polyester copolymer product.
- the product is a polyester homopolymer.
- the irradiation source is selected from the group consisting of a source of gamma radiation such as a cobalt source, X-rays, UV rays and high-energy electron beams.
- a source of gamma radiation such as a cobalt source, X-rays, UV rays and high-energy electron beams.
- the irradiation source is a cobalt source or high-energy electron beam.
- Methods of operating the irradiation process such as use of batch or continuous processing, use of totes or conveyor belts and process monitoring will be well known to those skilled in the art. Issues such as use of the correct packaging, heating of the material and generation and venting of gases produced during irradiation will be taken into account when operating the irradiation processes.
- the radiation dose used will be sufficient to render the polyester comminutable.
- the effects of irradiation include chain scission and/or cross-linking of the polyester chains. Suitable and sufficient chain scission and/or cross-linking change the chemical structure of the polymer result in alteration of the macroscopic properties of the polymer, rendering it comminutable. Chain scission reduces the average length of polymer strands and increases the number of end groups. Cross-linking introduces branching into the polyester. Irradiation is particularly useful for treating commercially available polyesters that are otherwise not readily comminutable by conventional methods.
- the dose required to render the polyester comminutable may vary and will normally be determined experimentally for each polyester on a case-by-case basis.
- the dose required is of the order of 300 IcGy to 700 kGy.
- Suitable chemical pre-treatments which can render the polyester comminutable include chemical treatments that can achieve suitable and sufficient chain scission and/or cross-linking such that the macroscopic properties of the polymer are altered sufficient to render it comminutable.
- Pre-treatments that can produce chain scission include hydrolysis, alcoholysis, acidolysis or aminolysis. Methods of carrying out such treatments on polyesters and similar polymers are well known to those skilled in the art.
- Pre-treatments that can produce cross-linking in a polyester will also be well known to those skilled in the art.
- Such methods include reactive blending in the presence of suitable cross-linking agents and initiators.
- Reactive blending is defined as a mixing process that is accompanied by chemical reaction(s) of the components of a polymer mixture.
- Examples of reactive blending include (a) blending accompanied by formation of polymer-polymer complex, (b) formation of block or graft copolymers by a combination of radicals formed by mechanochemical scission of respective polymers during blending.
- Reactive blending may also be carried out as a reactive extrusion or reaction inj ection molding (RIM) .
- Suitable initiators will be well known to those skilled in the art and include hydroperoxides, alkyl peresters, peroxides such as benzoyl peroxide, organic polyoxides, azo compounds such as azobisisobutyronitrile (AIBN), persulphates and percarbonates.
- hydroperoxides alkyl peresters
- peroxides such as benzoyl peroxide
- organic polyoxides organic polyoxides
- azo compounds such as azobisisobutyronitrile (AIBN)
- AIBN azobisisobutyronitrile
- Suitable cross-linking agents include compounds that are capable of forming 3 or more covalent bonds between polyester chains.
- Any compound capable of reacting with polyester chains to introduce a branch point may be used.
- Suitable compounds include polyols, such as diglycerol, triglycerol and polyglycerols; polycarboxylic acids; polyhydroxycarboxylic acids; polyamines; and polyamino acids. One of more of such compounds may be used. Typically, ester and/or amide bonds will be formed.
- Preferred compounds for incorporation include glycerol, polyvinyl alcohol, sorbitol, pentaerythritol or citric acid.
- Other suitable compounds including suitable polyhydroxycarboxylic acids, polyamines or polyamino acids that may be used to introduce branching into polyesters during synthesis will be apparent to those skilled in the art of polyester synthesis, including the art of dendrimer synthesis.
- suitable comminutable polyesters are those based on one or more of lactic acid, glycolic acid, lactide, glycolide, caprolactone and other suitable co- monomers such as those compounds useful for introducing branch points.
- polyesters with molecules that have functionality as oilfield treatment chemicals may also be possible.
- polycarboxylates have functionality as scale inhibitors.
- Other oilfield treatment chemicals may also be incorporated into the polyester by dispersion, before comminution and normally during when the polymer is in a molten state, for example by mixing prior to extrusion of a polymer melt to produce prills.
- Useful oilfield treatment chemicals include, but are not limited to, scale inhibitors, asphaltene inhibitors and corrosion inhibitors. Suitable oilfield chemicals that might be incorporated into the polyester by copolymerisation or dispersion during synthesis and extrusion processes and methods of incorporating such chemicals will be apparent to those skilled in the art of oilfield chemistry, polyester synthesis and handling of polymer melts.
- the polyester will be comminuted to produce particles with a particle size distribution suitable for the intended application. For oilfield applications this will normally be particles in the size range 1 micron to 2 mm, most preferably 10 microns to 100 microns.
- the method of rendering a polyester comminutable will be selected on a case by case basis depending on the characteristics required in the comminuted polyester in its specific application, the extent to which these characteristics are achieved by each method and by other considerations such as the cost.
- Example 1 The process of the present invention is further illustrated by the following example.
- Example 1 The process of the present invention is further illustrated by the following example.
- An extrusion grade of commercial polylactide resin was purchased from Cargill Dow. Conventional grinding processes were tried, including cryogenic grinding without success. The resin was irradiated at different radiation doses and at doses of 400 and 500 kGy the material became comminutable by a variety of grinding processes. Powders with mean diameters of 28 to 40 microns were obtained.
- the process of the invention has the following advantages over the prior art. It provides processes for obtaining powders of polyesters via standard mechanical comminution methods, where the untreated polyester would not otherwise be comminutable. It provides processes that do not require solvents or surfactant so do not contain residues of solvent or surfactant in the polyester powders produced.
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Polyesters Or Polycarbonates (AREA)
- Processes Of Treating Macromolecular Substances (AREA)
- Compositions Of Macromolecular Compounds (AREA)
Abstract
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/095,201 US8101675B2 (en) | 2005-11-28 | 2006-11-28 | Comminutable polyesters |
CA2631126A CA2631126C (en) | 2005-11-28 | 2006-11-28 | Comminutable polyesters |
GB0811857A GB2446764B (en) | 2005-11-28 | 2008-06-27 | Comminutable polyesters |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GBGB0524196.3A GB0524196D0 (en) | 2005-11-28 | 2005-11-28 | Comminutable polyesters |
GB0524196.3 | 2005-11-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2007060470A1 true WO2007060470A1 (en) | 2007-05-31 |
Family
ID=35601357
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/GB2006/004432 WO2007060470A1 (en) | 2005-11-28 | 2006-11-28 | Comminutable polyesters |
Country Status (4)
Country | Link |
---|---|
US (1) | US8101675B2 (en) |
CA (1) | CA2631126C (en) |
GB (2) | GB0524196D0 (en) |
WO (1) | WO2007060470A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012098340A1 (en) * | 2011-01-20 | 2012-07-26 | Arkema France | Fine powder of biosourced aliphatic polyester and production method thereof |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10442966B2 (en) * | 2012-11-15 | 2019-10-15 | Purdue Research Foundation | Polylactic acid adhesive compositions and methods for their preparation and use |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1273367A (en) * | 1968-09-17 | 1972-05-10 | Fmc Corp | Polyester |
EP0984039A1 (en) * | 1998-03-12 | 2000-03-08 | DAICEL CHEMICAL INDUSTRIES, Ltd. | Lactone-containing resin composition, molded object thereof, and film |
US20010022327A1 (en) * | 2000-03-11 | 2001-09-20 | Olaf Mientkewitz | Process for increasing the effectiveness of the comminution of bulk materials by oxidation |
Family Cites Families (24)
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US2362511A (en) * | 1939-11-21 | 1944-11-14 | Du Pont | Modified glycolide resins |
US4029870A (en) * | 1970-02-03 | 1977-06-14 | Imperial Chemical Industries Limited | Tetrafluoroethylene polymers |
US3766031A (en) | 1972-04-10 | 1973-10-16 | Garlock Inc | Process for non-destructive radiation degradation of polytetrafluoroethylene |
US4220511A (en) | 1979-03-12 | 1980-09-02 | Radiation Dynamics, Inc. | Treatment of sintered poly-tetrafluoroethylene with irradiation and heat to produce a grindable material |
ES2034368T3 (en) | 1987-10-08 | 1993-04-01 | Walter Neukomm | STRAIGHT KNITTING MACHINE. |
US5049465A (en) * | 1988-11-15 | 1991-09-17 | Somar Corporation | Electrophotographic photosensitive material and method of preparing same |
US4986355A (en) | 1989-05-18 | 1991-01-22 | Conoco Inc. | Process for the preparation of fluid loss additive and gel breaker |
DE19529348C2 (en) | 1995-08-09 | 1997-11-20 | Stockhausen Chem Fab Gmbh | Absorbent for water and aqueous liquids based on polyacrylate and process for their production and use |
DE19540951A1 (en) * | 1995-11-03 | 1997-05-07 | Basf Ag | Water-absorbent, foam-like, crosslinked polymers, processes for their preparation and their use |
US5916929A (en) | 1997-06-23 | 1999-06-29 | E-Beam Services, Inc. | Method for irradiating organic polymers |
US6096810A (en) * | 1997-09-18 | 2000-08-01 | Monsanto Company | Modified polyhydroxyalkanoates for production of coatings and films |
DE19846413A1 (en) | 1998-10-08 | 2000-04-13 | Basf Ag | Economical preparation of swellable, hydrophilic polymer having good water absorption properties, useful e.g. in hygienic articles, by polymerization, comminution, post-neutralization, drying, grinding and sieving |
US6319521B1 (en) | 1999-02-10 | 2001-11-20 | University Technology Corporation | Microparticles of lactide-co-glycolide copolymers and methods of making and using the same |
US6376585B1 (en) * | 2000-06-26 | 2002-04-23 | Apex Advanced Technologies, Llc | Binder system and method for particulate material with debind rate control additive |
AU2003278106A1 (en) * | 2002-10-28 | 2004-05-13 | Sofitech N.V. | Self-destructing filter cake |
GB2412389A (en) * | 2004-03-27 | 2005-09-28 | Cleansorb Ltd | Process for treating underground formations |
TW200630415A (en) | 2004-12-21 | 2006-09-01 | Clariant Int Ltd | Process for the preparation of cross-linked PBT particles |
US7267170B2 (en) | 2005-01-31 | 2007-09-11 | Halliburton Energy Services, Inc. | Self-degrading fibers and associated methods of use and manufacture |
US20080009423A1 (en) | 2005-01-31 | 2008-01-10 | Halliburton Energy Services, Inc. | Self-degrading fibers and associated methods of use and manufacture |
US20070298977A1 (en) | 2005-02-02 | 2007-12-27 | Halliburton Energy Services, Inc. | Degradable particulate generation and associated methods |
US20060172895A1 (en) | 2005-02-02 | 2006-08-03 | Halliburton Energy Services, Inc. | Degradable particulate generation and associated methods |
US8598092B2 (en) | 2005-02-02 | 2013-12-03 | Halliburton Energy Services, Inc. | Methods of preparing degradable materials and methods of use in subterranean formations |
US20060172894A1 (en) | 2005-02-02 | 2006-08-03 | Halliburton Energy Services, Inc. | Degradable particulate generation and associated methods |
US20060169450A1 (en) | 2005-02-02 | 2006-08-03 | Halliburton Energy Services, Inc. | Degradable particulate generation and associated methods |
-
2005
- 2005-11-28 GB GBGB0524196.3A patent/GB0524196D0/en not_active Ceased
-
2006
- 2006-11-28 CA CA2631126A patent/CA2631126C/en active Active
- 2006-11-28 WO PCT/GB2006/004432 patent/WO2007060470A1/en active Application Filing
- 2006-11-28 US US12/095,201 patent/US8101675B2/en active Active
-
2008
- 2008-06-27 GB GB0811857A patent/GB2446764B/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1273367A (en) * | 1968-09-17 | 1972-05-10 | Fmc Corp | Polyester |
EP0984039A1 (en) * | 1998-03-12 | 2000-03-08 | DAICEL CHEMICAL INDUSTRIES, Ltd. | Lactone-containing resin composition, molded object thereof, and film |
US20010022327A1 (en) * | 2000-03-11 | 2001-09-20 | Olaf Mientkewitz | Process for increasing the effectiveness of the comminution of bulk materials by oxidation |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012098340A1 (en) * | 2011-01-20 | 2012-07-26 | Arkema France | Fine powder of biosourced aliphatic polyester and production method thereof |
FR2970713A1 (en) * | 2011-01-20 | 2012-07-27 | Arkema France | BIORESSOURCE ALIPHATIC POLYESTER FINE POWDER AND PROCESS FOR PRODUCING SUCH POWDER |
JP2014503025A (en) * | 2011-01-20 | 2014-02-06 | アルケマ フランス | Fine powder of bio-origin aliphatic polyester and production method thereof |
US8802814B2 (en) | 2011-01-20 | 2014-08-12 | Arkema France | Fine powder of biosourced aliphatic polyester and production method thereof |
Also Published As
Publication number | Publication date |
---|---|
CA2631126C (en) | 2012-08-21 |
GB0811857D0 (en) | 2008-07-30 |
GB2446764A (en) | 2008-08-20 |
CA2631126A1 (en) | 2007-05-31 |
US20080293843A1 (en) | 2008-11-27 |
GB2446764B (en) | 2010-06-09 |
GB0524196D0 (en) | 2006-01-04 |
US8101675B2 (en) | 2012-01-24 |
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