WO1998012035A1 - Verfahren zur formgebung von pulverförmigen, thermisch instabilen thermoplastformmassen - Google Patents
Verfahren zur formgebung von pulverförmigen, thermisch instabilen thermoplastformmassen Download PDFInfo
- Publication number
- WO1998012035A1 WO1998012035A1 PCT/DE1997/001969 DE9701969W WO9812035A1 WO 1998012035 A1 WO1998012035 A1 WO 1998012035A1 DE 9701969 W DE9701969 W DE 9701969W WO 9812035 A1 WO9812035 A1 WO 9812035A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- shaping
- thermoplastic molding
- powdery
- thermally unstable
- compounds
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 23
- 238000007493 shaping process Methods 0.000 title claims abstract description 9
- 150000001875 compounds Chemical class 0.000 title abstract description 12
- 229920001169 thermoplastic Polymers 0.000 title abstract 3
- 239000004416 thermosoftening plastic Substances 0.000 title abstract 3
- 238000002844 melting Methods 0.000 claims abstract description 8
- 230000008018 melting Effects 0.000 claims abstract description 8
- 230000002706 hydrostatic effect Effects 0.000 claims abstract description 3
- 238000009757 thermoplastic moulding Methods 0.000 claims description 14
- 239000000203 mixture Substances 0.000 claims description 11
- 229920001577 copolymer Polymers 0.000 claims description 2
- 239000000945 filler Substances 0.000 claims description 2
- 239000005014 poly(hydroxyalkanoate) Substances 0.000 claims description 2
- 229920000747 poly(lactic acid) Polymers 0.000 claims description 2
- 229920000903 polyhydroxyalkanoate Polymers 0.000 claims description 2
- 239000002253 acid Substances 0.000 claims 1
- 230000001580 bacterial effect Effects 0.000 claims 1
- 238000000855 fermentation Methods 0.000 claims 1
- 230000004151 fermentation Effects 0.000 claims 1
- 239000006259 organic additive Substances 0.000 claims 1
- 239000012779 reinforcing material Substances 0.000 claims 1
- 239000011265 semifinished product Substances 0.000 abstract description 9
- 238000005979 thermal decomposition reaction Methods 0.000 abstract 1
- 238000000465 moulding Methods 0.000 description 9
- 238000001125 extrusion Methods 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 6
- 239000002245 particle Substances 0.000 description 6
- 238000005245 sintering Methods 0.000 description 6
- 229920000642 polymer Polymers 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 238000006731 degradation reaction Methods 0.000 description 4
- 238000003825 pressing Methods 0.000 description 4
- 239000002861 polymer material Substances 0.000 description 3
- 239000007790 solid phase Substances 0.000 description 3
- 229920000331 Polyhydroxybutyrate Polymers 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000155 melt Substances 0.000 description 2
- 238000009931 pascalization Methods 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 239000005015 poly(hydroxybutyrate) Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- 239000004952 Polyamide Substances 0.000 description 1
- 239000004621 biodegradable polymer Substances 0.000 description 1
- 229920002988 biodegradable polymer Polymers 0.000 description 1
- 239000001506 calcium phosphate Substances 0.000 description 1
- 235000011010 calcium phosphates Nutrition 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000000748 compression moulding Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- -1 for example Polymers 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 239000012778 molding material Substances 0.000 description 1
- 239000012768 molten material Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004014 plasticizer Substances 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000012744 reinforcing agent Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
- 230000003685 thermal hair damage Effects 0.000 description 1
- QORWJWZARLRLPR-UHFFFAOYSA-H tricalcium bis(phosphate) Chemical class [Ca+2].[Ca+2].[Ca+2].[O-]P([O-])([O-])=O.[O-]P([O-])([O-])=O QORWJWZARLRLPR-UHFFFAOYSA-H 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
- B29C43/02—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor of articles of definite length, i.e. discrete articles
- B29C43/16—Forging
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C43/00—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor
- B29C43/003—Compression moulding, i.e. applying external pressure to flow the moulding material; Apparatus therefor characterised by the choice of material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C2791/00—Shaping characteristics in general
- B29C2791/001—Shaping in several steps
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2067/00—Use of polyesters or derivatives thereof, as moulding material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
- B29K2105/25—Solid
- B29K2105/251—Particles, powder or granules
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
- B29K2105/25—Solid
- B29K2105/253—Preform
- B29K2105/255—Blocks or tablets
Definitions
- the invention relates to a method for shaping131-shaped, thermally unstable thermoplastic molding compositions, in particular for the production of semi-finished products or molded parts.
- thermoplastic molding compositions can be converted into a molten state by the application of heat, in which compression and shaping of the material can be carried out effectively using suitable technologies (e.g. compression molding, extrusion, injection molding).
- suitable technologies e.g. compression molding, extrusion, injection molding.
- stabilizers, plasticizers, etc. an increase in the resistance to thermal degradation can be achieved.
- it is often not possible to use these substances if there are high demands on the purity of the molding compounds (e.g. when used in medical technology or in the food industry).
- Solid-phase extrusion techniques are known for the molding of plastics in the solid state, in which a preform of defined dimensions is pressed through a conical nozzle at temperatures below the melting temperature (NE Weeks, S Mon, RS Porter Journal of Polymer Science, Polymer Physics 13 (1975) 2031 , YD Wang, T Yamamoto, M Cakmak ANTEC'96 S 1654-1665)
- the goal of solid-phase extrusion is the production of highly oriented structures with improved strength properties.
- a disadvantage of this in particular for thermally sensitive polymers is that the material in the molten material is used to produce the preform Condition is transferred.
- the invention has for its object to process powdery, thermally and also hydrolytically unstable thermoplastic molding compositions so that they can be further processed as semifinished products or represent usable moldings.
- the thermal degradation processes that take place in the processing of thermoplastic molding compositions are to be prevented, so that the semifinished products or moldings are prevented a high level of mechanical properties are characterized
- thermoplastic molding compounds can be, for example, preferred polyolefins, polyamides or polyesters
- thermally unstable polymers such as, for example, biodegradable polymers, in particular polylactides and polyhydroxyalkanoates, and copolymers thereof are used.
- the initially powdery starting material is precompressed to a preform in a first process step using hydrostatic pressure.This is done with the aim of minimizing thermal damage, preferably at room temperature, but it can also be carried out at elevated temperatures, but in any case well below the melting temperature.
- the pressure must be chosen so that the density of the preform reaches about 75 to 90% of the bulk density of the polymer material
- the pre-compressed preform is subjected to deviatoric stress in a second step, extrusion.
- deviatoric stress in a second step, extrusion.
- the mutual penetration of neighboring particles takes place as a result of molecular movement processes in the boundary layer, as well as the removal of existing micropores in the material.
- the desired geometry of the molded part or semifinished product is formed by means of targeted form constraint.
- the preform can be produced at room temperature
- flow processes under deviatoric stress must be carried out at elevated temperatures in the range between glass and melting temperature, preferably at temperatures from 0.8 to 0.95 T m [K], in order to ensure intensive penetration
- the load under deviatoric stress is expediently chosen depending on the type of polymer material and the forming temperature in such a way that forming ratios of 1, 5 -, ⁇ ⁇ 3 are achieved.
- the deformation is preferably carried out under continuously increasing stress .
- the powdery thermoplastic molding compound can also contain fillers and / or Reinforcing agents such as calcium phosphates are added.
- the molded parts and semi-finished products produced according to the invention are distinguished by a property level which is considerably improved in comparison to products of conventional processing technologies.
- a property level which is considerably improved in comparison to products of conventional processing technologies.
- strength, ductility and toughness they are clearly superior to products that have been processed in the melt state, but also hydrostatically pressed in the solid state and products that are solidified by sintering.
- PHB polyhydroxybutyrate
- the density of the material is increased to 1.25 g / cm 3 by extrusion. Associated with this are significant improvements in mechanical properties, in particular tensile strength and elongation at break. Molecular degradation processes cannot be demonstrated.
- Selected characteristic values of the semi-finished products manufactured according to different processes in Figure 1 document the superiority of the extrusion technology according to the invention.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
- Materials For Medical Uses (AREA)
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA002267357A CA2267357A1 (en) | 1996-09-18 | 1997-09-05 | Method of shaping powdery, thermally unstable thermoplastic shaping compounds |
EP97954859A EP0944463A1 (de) | 1996-09-18 | 1997-09-05 | Verfharen zur formgebung von pulvörmigen, thermisch instabilen thermoplastformmassen |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1996137904 DE19637904A1 (de) | 1996-09-18 | 1996-09-18 | Verfahren zur Formgebung von pulverförmigen, thermisch instabilen Thermoplastformmassen |
DE19637904.0 | 1996-09-18 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998012035A1 true WO1998012035A1 (de) | 1998-03-26 |
Family
ID=7805916
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/DE1997/001969 WO1998012035A1 (de) | 1996-09-18 | 1997-09-05 | Verfahren zur formgebung von pulverförmigen, thermisch instabilen thermoplastformmassen |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0944463A1 (de) |
CA (1) | CA2267357A1 (de) |
DE (1) | DE19637904A1 (de) |
WO (1) | WO1998012035A1 (de) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10054431B4 (de) * | 2000-10-26 | 2009-12-03 | Volkswagen Ag | Verfahren zum Lackieren eines Kunststoff-Karosserieteils sowie Tempergestell |
US9475217B2 (en) | 2013-01-31 | 2016-10-25 | Saudi Basic Industries Corporation | Process for making highly crystalline shaped part from pet or pen |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2025949A1 (de) * | 1969-05-28 | 1970-12-03 | Carborundum Co | Verfahren zum Formen von Polyestern |
US4014965A (en) * | 1972-11-24 | 1977-03-29 | The Dow Chemical Company | Process for scrapless forming of plastic articles |
US4323531A (en) * | 1971-03-01 | 1982-04-06 | The Dow Chemical Company | Process for forming a plastic article |
FR2602454A1 (fr) * | 1986-08-11 | 1988-02-12 | Medico Chirurgical Intern Off | Procede et dispositif permettant d'obtenir des pieces en polymere forgees, et application des pieces ainsi obtenues a la preparation de protheses orthopediques |
DE4308239A1 (de) * | 1992-12-08 | 1994-06-09 | Artos Med Produkte | Verfahren zur Herstellung eines Formkörpers für die Osteosynthese |
US5529736A (en) * | 1994-08-10 | 1996-06-25 | Clemson University | Process of making a bone healing device |
WO1997010010A1 (fr) * | 1995-09-14 | 1997-03-20 | Takiron Co., Ltd. | Materiau d'osteosynthese, materiau d'implant composite et procede de preparation dudit materiau |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL6816523A (de) * | 1967-11-22 | 1969-05-27 | ||
DE3002910A1 (de) * | 1980-01-28 | 1981-07-30 | Basf Ag, 6700 Ludwigshafen | Verfahren zur herstellung eines formkoerpers aus pulver- bis granulatfoermigem thermoplastischem kunststoff |
DE3611688A1 (de) * | 1986-04-08 | 1987-10-22 | Hansa Metallwerke Ag | Verfahren und vorrichtung zur herstellung eines kunststoff-formkoerpers |
DE3611687A1 (de) * | 1986-04-08 | 1987-10-15 | Hansa Metallwerke Ag | Verfahren zur herstellung von kunststoff-formkoerpern |
DE4012851A1 (de) * | 1990-04-19 | 1991-10-24 | Gerhard Dr Ing Frey | Verfahren und vorrichtung zum fertigen von hochfesten bauteilen und gegenstaenden aus kunststoff durch verfahren des umformens |
-
1996
- 1996-09-18 DE DE1996137904 patent/DE19637904A1/de not_active Withdrawn
-
1997
- 1997-09-05 EP EP97954859A patent/EP0944463A1/de not_active Withdrawn
- 1997-09-05 CA CA002267357A patent/CA2267357A1/en not_active Abandoned
- 1997-09-05 WO PCT/DE1997/001969 patent/WO1998012035A1/de not_active Application Discontinuation
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2025949A1 (de) * | 1969-05-28 | 1970-12-03 | Carborundum Co | Verfahren zum Formen von Polyestern |
US4323531A (en) * | 1971-03-01 | 1982-04-06 | The Dow Chemical Company | Process for forming a plastic article |
US4014965A (en) * | 1972-11-24 | 1977-03-29 | The Dow Chemical Company | Process for scrapless forming of plastic articles |
FR2602454A1 (fr) * | 1986-08-11 | 1988-02-12 | Medico Chirurgical Intern Off | Procede et dispositif permettant d'obtenir des pieces en polymere forgees, et application des pieces ainsi obtenues a la preparation de protheses orthopediques |
DE4308239A1 (de) * | 1992-12-08 | 1994-06-09 | Artos Med Produkte | Verfahren zur Herstellung eines Formkörpers für die Osteosynthese |
US5529736A (en) * | 1994-08-10 | 1996-06-25 | Clemson University | Process of making a bone healing device |
WO1997010010A1 (fr) * | 1995-09-14 | 1997-03-20 | Takiron Co., Ltd. | Materiau d'osteosynthese, materiau d'implant composite et procede de preparation dudit materiau |
EP0795336A1 (de) * | 1995-09-14 | 1997-09-17 | Takiron Co. Ltd. | Osteosynthetisches material, verbundwerkstoff für implantate und verfahren zu ihrer herstellung |
Non-Patent Citations (2)
Title |
---|
WANG Y D: "PROCESSING CHARACTERISTICS AND STRUCTURE DEVELOPMENT IN SOLID STATE EXTRUSION OF BACTERIAL COPOLYESTERS", ANTEC '96 (SOCIETY OF PLASTICS ENGINEERS), 5 May 1996 (1996-05-05) - 10 May 1996 (1996-05-10), BROOKFIELD US, pages 1654 - 1665, XP002052506 * |
WEEKS NORMAN E: "THE MORPHOLOGY OF ULTRADRAWN POLYETHYLENE", JOURNAL OF POLYMER SCIENCE, POLYMER PHYSICS EDITION., vol. 13, 1975, NEW YORK US, pages 2031 - 2048, XP002052507 * |
Also Published As
Publication number | Publication date |
---|---|
DE19637904A1 (de) | 1998-03-19 |
EP0944463A1 (de) | 1999-09-29 |
CA2267357A1 (en) | 1998-03-26 |
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