GB2116981A - Alcoholysis of olefin/vinyl ester copolymers - Google Patents
Alcoholysis of olefin/vinyl ester copolymers Download PDFInfo
- Publication number
- GB2116981A GB2116981A GB08306541A GB8306541A GB2116981A GB 2116981 A GB2116981 A GB 2116981A GB 08306541 A GB08306541 A GB 08306541A GB 8306541 A GB8306541 A GB 8306541A GB 2116981 A GB2116981 A GB 2116981A
- Authority
- GB
- United Kingdom
- Prior art keywords
- copolymers
- alcoholysis
- metal alcoholates
- reaction
- melt
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000006136 alcoholysis reaction Methods 0.000 title claims abstract description 9
- 229920001567 vinyl ester resin Polymers 0.000 title abstract description 8
- 150000001336 alkenes Chemical class 0.000 title 1
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 title 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229920001577 copolymer Polymers 0.000 claims abstract description 14
- 238000000034 method Methods 0.000 claims abstract description 13
- 238000006243 chemical reaction Methods 0.000 claims abstract description 12
- 229910052751 metal Inorganic materials 0.000 claims abstract description 11
- 239000002184 metal Substances 0.000 claims abstract description 11
- 229920003023 plastic Polymers 0.000 claims abstract description 9
- 239000011541 reaction mixture Substances 0.000 claims abstract description 8
- 230000001476 alcoholic effect Effects 0.000 claims abstract description 7
- 238000004132 cross linking Methods 0.000 claims abstract description 4
- 230000000694 effects Effects 0.000 claims abstract description 3
- 125000004185 ester group Chemical group 0.000 claims abstract description 3
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 3
- 238000002844 melting Methods 0.000 claims abstract description 3
- 230000008018 melting Effects 0.000 claims abstract description 3
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 claims description 11
- 229920000089 Cyclic olefin copolymer Polymers 0.000 claims description 10
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims description 9
- 239000005977 Ethylene Substances 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 claims description 5
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 36
- WQDUMFSSJAZKTM-UHFFFAOYSA-N Sodium methoxide Chemical compound [Na+].[O-]C WQDUMFSSJAZKTM-UHFFFAOYSA-N 0.000 description 16
- 238000001125 extrusion Methods 0.000 description 9
- 239000000047 product Substances 0.000 description 9
- 239000000155 melt Substances 0.000 description 8
- 238000007872 degassing Methods 0.000 description 7
- 239000000243 solution Substances 0.000 description 7
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical group CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 6
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000003513 alkali Substances 0.000 description 3
- 238000001704 evaporation Methods 0.000 description 3
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 150000001298 alcohols Chemical class 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000007127 saponification reaction Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical class CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical class CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- USFNELLLQLCMSH-UHFFFAOYSA-N sodium;dodecan-1-olate Chemical compound [Na+].CCCCCCCCCCCC[O-] USFNELLLQLCMSH-UHFFFAOYSA-N 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
- C08F8/12—Hydrolysis
-
- 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
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F2800/00—Copolymer characterised by the proportions of the comonomers expressed
- C08F2800/20—Copolymer characterised by the proportions of the comonomers expressed as weight or mass percentages
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F2810/00—Chemical modification of a polymer
- C08F2810/50—Chemical modification of a polymer wherein the polymer is a copolymer and the modification is taking place only on one or more of the monomers present in minority
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
A process for producing modified olefin-vinyl ester copolymers, e.g. EVA, by reaction of the copolymers with alcoholic metal alcoholates or solutions of metal alcoholates in the corresponding alcohol at melting points of 343 to 493 DEG K, to effect predetermined partial or total cross-linked products in which ester groups are replaced, in 5 to 95% alcoholysis, by hydroxyl groups, in which process the alcoholysis reactions and cross-linking reactions take place together and are effected by removal of a proportion of alcohol amounting to 5 to 98 % by mass from the reaction mixture after the plastic melt has remained in the processing machine for 15 to 95% of the total time for which the said melt remains in the said machine.
Description
SPECIFICATION
Process for production of modified olefin copolymers containing vinyl ester
This invention relates to a process for the production of olefin copolymers containing vinyl ester and modified by reaction with alcoholic metal alcoholates, whereby the qualitative characteristics of the copolymers can be modified.
Methods are known in which olefin copolymers containing vinyl ester are cross-linked with metal alcoholates, such as alkali alcoholates (DD 70388) at temperatures between 333 and 523 K. Methods are also known in which olefin copolymers containing vinyl esters are saponified in the presence of alcoholates or alcoholic lyes (DD 107938). Examples of possible saponification agents are sodium hydroxide dissolved in methanol and potassium hydroxide, dissolved in ethanol. For the alcoholysis, however, solutions of metal alcoholates in the corresponding alcohol are also known, for example in the alcoholysis of copolymers of ethylene and vinyl acetate in methanol at reaction temperatures in the range 373 to 503"K.
The processes mentioned do not provide a means for the planned cross-linking and saponification of olefin copolymers containing vinyl ester.
An object of this invention is to modify olefin copolymers containing vinyl ester by reaction with alcoholic metal alcoholates, whereby the reactions taking place are influenced in such a way that partial or total cross-linked products with a defined degree of hydrolysis can be obtained in a predetermined manner.
According to this invention there is provided a process for the production of olefin copolymers by reaction of the copolymers with alcoholic metal alcoholates or solutions of metal alcoholates in the corresponding alcohol at melting points of 343 to 493"K, to effect predetermined partial or total cross
linked products in which ester groups are replaced" in 5 to 95% alcoholysis, by hydroxyl groups, in which process the alcoholysis reactions and crosslinking reactions take place together and are effected by removal of a proportion of alcohol amounting to 5 to 98% by mass from the reaction mixture after the plastic melt has remained in the processing machine for 15 to 95% of the total time for which the said melt remains in the said machine.
The reactions are carried out in a manner known in the aforementioned temperature range, the modification agents preferably comprise solutions of alkali alcoholates in the corresponding alcohol. It is of advantage to use alcoholates of lower alcohols, such as methanol, ethanol, propanols and butanols.
It is nevertheless also possible to use metal salts of higher alcohols, such as sodium palmitylate or sodium dodecylate.
The modification can be effected in internal mixers and extrusion machines, the most advantageous version from the technical point of view is the double-worm extruder. The removal of defined proportions of alcohol is effected, for example, by vacuum degasification. The reaction products obtained at the extruder end can be expanded to a greater or lesser extent by the escaping residual alcohol, in which case the degasification must follow on from the modification. The time for which the reaction mixture remains in the apparatus depends on the reactivity of the alcoholate, the concentration of the free alcohol in the alcoholate concerned, the, temperature and also the nature and geometrical shape of the plastic processing machine.In the modification of copolymers of ethylene and vinyl acetate with alcoholic alkali alcoholates in a doubleworm extruder under the aforementioned reaction conditions, the mixture can be left in the machine for perIods of 5to 10 minutes, as example. Longer periods are possible.
Examples:
Example 1
A copolymer of ethylene and vinyl acetate with a vinyl acetate content of 31.5% by mass and a melt index of 175 girl 0 minutes at 463"K is passed at a rate of 2.0 kg/h through a double-worm extruder with a worm diameter of 28 mm and a worm length of 929 mm. The temperature of the individual heating zones are in the range 403 to 473"K. 160 ml/h of a sodium methylate solution having a sodium methylate content of 7.5% by mass is injected into the-, plastic melt by means of a dosing pump. 130 mm beyond the dose injection point and after the reaction mixture has remained in the extruder for 20 seconds 60% by mass of the free methanol is removed from the plastic melt by vacuum degasification.
The extrusion leaving the extruder is expanded to some extent by the methanol during evaporation.
After passing through a cooling vat the extrusion is granulated. The resulting product, in which 34% of the acetate groups are saponified, has a light yellow colour. The melt index measured at 463"K, is within the range 27 to 35 g/10 minutes.
Example 2 (comparative example)
In accordance with Example 1 to the copolymer of ethylene and vinyl acetate is added the sodium methylate solution as described in the foregoing. No removal of free methanol by vacuum degasification was carried out. The time for which the reaction mixture remains in the extruder amounts to about 1 minute.
The extrusion leaving the extruder is considerably expanded by methanol in the course of evaporation.
This results in a hard yellowish-white product in which 71% of the acetate groups are saponified. The melt index measured at 463"K is within the range 121 to 134 g/10 minutes.
Example 3
In accordance with Example 1 to the copolymer of ethylene and vinyl acetate is added methylate solution as described in the foregoing. 130 mm beyond the dose injection point for the methanolic sodium methylate 98% by mass of free methanol is removed from the plastic melt by vacuum degasification. The extrusion leaving the extruder is transparent and has a light yellow colour. 5% of the acetate groups contained in the initial product are saponified. The melt index, measured at 463 K, is in the range 2.3 to 5.1 g/10 minutes.
Example 4
In accordance with Example 1 to the copolymer of
ethylene and vinyl acetate is added the sodium
methylate solution as described in the foregoing.
450 mm beyond the dose injection point for
methanolic sodium methylate and after the reaction
mixture has remained in the extruderfor about 45 seconds. 98% by mass of free methanol is removed from the polymer melt by vacuum degasification.
The extrusion leaving the extruder is transparent and has a light yellow colour. The melt index of the resulting product, measured at 463"K, is in the range 18to 25 gM0 minutes. 45% of the acetate groups contained in the initial product are saponified.
Example 5
A copolymer of ethylene and vinyl acetate with a vinyl acetate content of 31.5% by weight, and a melt index of 175 g/10 minutes at 463"K is fed at a rate of 2.0 kg/h through a double-worm extruder such as that described in Example 1. The temperature of the individual heating zones are in the range 383 to 433"K. 18.5 g/h of a solid sodium methylate containing 49% by mass of free methanol is dosed in an inert gas atmosphere into the plastic melt at a point 380 mm distant from the filling shaft. The period for which the reaction mixture remains in the extruder amounts to about 1 minute.
The extrusion leaving the extruder is to some extent expanded by the methanol in the course of evaporating. After passing through a cooling vat the extrusion is granulated. This results in a light yellow product in which 17% of the acetate groups are saponified. The melt index, measured at 463"K, is within the range 20 to 25 g/10 minutes.
Example 6
In accordance with Example 1, 18.5 g/h of a solid methanolic sodium methylate is added to the copolymer of ethylene and vinyl acetate. 130 mm beyond the feed point, 97% by mass of the free methanol is removed from the plastic melt by vacuum degasification.
The extrusion leaving the extruder is transparent and light yellow. This results in a product in which 3% of the acetate groups are saponified. The melt index, measured at 463"K, is in the range 3.1 to 6.2 g/10 minutes.
Claims (4)
1. Processforthe production of olefin copolymers by reaction of the copolymers with alcoholic metal alcoholates or solutions of metal alcoholates in the corresponding alcohol at melting points of 343 to 493"K, to effect predetermined partial or total cross-linked products in which ester groups are replaced, in 5 to 95% alcoholysis, by hydroxyl groups, in which process the alcoholysis reactions and cross-linking reactions take place together and are effected by removal of a proportion of alcohol amounting to 5 to 98% by mass from the reaction
mixture after the plastic melt has remained in the
processing machine for 15 to 95% of the total time for which the said melt remains in the said machine.
2. Process in accordance with Claim 1, wherein the copolymers are modified copolymers of ethylene
and vinyl acetate.
3. Process for production of olefin copolymers as described herein and exemplified.
4. Modified olefin copolymers produced by a process as described herein and claimed.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DD82238127A DD206900A3 (en) | 1982-03-15 | 1982-03-15 | METHOD FOR PRODUCING MODIFIED VINYL ETHER-BASED OLEFIN COPOLYMERISES |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8306541D0 GB8306541D0 (en) | 1983-04-13 |
| GB2116981A true GB2116981A (en) | 1983-10-05 |
| GB2116981B GB2116981B (en) | 1985-10-09 |
Family
ID=5537245
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08306541A Expired GB2116981B (en) | 1982-03-15 | 1983-03-09 | Alcoholysis of olefin/vinyl ester copolymers |
Country Status (5)
| Country | Link |
|---|---|
| DD (1) | DD206900A3 (en) |
| DE (1) | DE3308516A1 (en) |
| FR (1) | FR2523138B1 (en) |
| GB (1) | GB2116981B (en) |
| SU (1) | SU1599380A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2593508A1 (en) * | 1985-12-16 | 1987-07-31 | Leuna Werke Veb | Process for the manufacture of modified ethylene-vinyl acetate copolymers |
| WO1992009549A1 (en) * | 1990-11-27 | 1992-06-11 | Micronisers Pty. Ltd | Polymeric materials |
| WO2000055213A1 (en) * | 1999-03-15 | 2000-09-21 | Multibase S.A. | Crosslinking of vinyl acetate polymers or copolymers, preparation of dynamically crosslinked compositions and hybrid organic-inorganic compositions preserving a thermoplastic character |
| EP1046673A4 (en) * | 1998-09-28 | 2002-01-16 | Kuraray Co | PROCESS FOR PRODUCING A VINYL ALCOHOL POLYMER COMPOSITION |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2567894B1 (en) * | 1984-07-18 | 1986-08-08 | Atochem | PROCESS FOR HYDROLYSIS OF POLYMERS COMPRISING IN THEIR CHAIN AN UNSATURATED ALCOHOL ESTER |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB691825A (en) * | 1950-04-22 | 1953-05-20 | Du Pont | Improvements in production of polyvinyl alcohol |
| GB1057898A (en) * | 1963-05-29 | 1967-02-08 | Hoechst Ag | Process for preparing copolymers |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1106489A (en) * | 1966-01-07 | 1968-03-20 | Monsanto Chemicals | Production of polymers |
| DD107938A1 (en) * | 1973-03-23 | 1974-08-20 | ||
| GB1468793A (en) * | 1974-02-18 | 1977-03-30 | Nat Distillers Chem Corp | Process forthe controlled alcoholysis of ethylene-vinyl ester interpolymers |
-
1982
- 1982-03-15 DD DD82238127A patent/DD206900A3/en not_active IP Right Cessation
-
1983
- 1983-02-10 SU SU837772838A patent/SU1599380A1/en active
- 1983-03-09 GB GB08306541A patent/GB2116981B/en not_active Expired
- 1983-03-10 DE DE19833308516 patent/DE3308516A1/en active Granted
- 1983-03-15 FR FR8304247A patent/FR2523138B1/en not_active Expired
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB691825A (en) * | 1950-04-22 | 1953-05-20 | Du Pont | Improvements in production of polyvinyl alcohol |
| GB1057898A (en) * | 1963-05-29 | 1967-02-08 | Hoechst Ag | Process for preparing copolymers |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2593508A1 (en) * | 1985-12-16 | 1987-07-31 | Leuna Werke Veb | Process for the manufacture of modified ethylene-vinyl acetate copolymers |
| WO1992009549A1 (en) * | 1990-11-27 | 1992-06-11 | Micronisers Pty. Ltd | Polymeric materials |
| US5475123A (en) * | 1990-11-27 | 1995-12-12 | Micronisers Pty. Ltd. | Polymeric materials |
| EP1046673A4 (en) * | 1998-09-28 | 2002-01-16 | Kuraray Co | PROCESS FOR PRODUCING A VINYL ALCOHOL POLYMER COMPOSITION |
| US6444751B1 (en) | 1998-09-28 | 2002-09-03 | Kuraray Co., Ltd. | Process for producing vinyl alcohol polymer composition |
| WO2000055213A1 (en) * | 1999-03-15 | 2000-09-21 | Multibase S.A. | Crosslinking of vinyl acetate polymers or copolymers, preparation of dynamically crosslinked compositions and hybrid organic-inorganic compositions preserving a thermoplastic character |
| FR2791062A1 (en) * | 1999-03-15 | 2000-09-22 | Multibase Sa | CROSS-LINKING OF POLYMERS OR COPOLYMERS OF VINYL ACETATE, PREPARATION OF DYNAMICALLY CROSS-LINKED THERMOPLASTIC ELASTOMERS AND ORGANIC-INORGANIC HYBRID MATERIALS |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8306541D0 (en) | 1983-04-13 |
| DD206900A3 (en) | 1984-02-08 |
| FR2523138A1 (en) | 1983-09-16 |
| FR2523138B1 (en) | 1986-09-12 |
| SU1599380A1 (en) | 1990-10-15 |
| DE3308516C2 (en) | 1992-09-03 |
| DE3308516A1 (en) | 1983-09-29 |
| GB2116981B (en) | 1985-10-09 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |