Biobased rubber modified biodegradable polymer blends

Patent metadata

Field	Value
Publication number	US-10113060-B2
Application number	US-201314406131-A
Country	US
Kind code	B2
Filing date	Jun 5, 2013
Priority date	Jun 5, 2012
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

Compositions of biobased polymer blends of polymers and a polyhydroxyalkanoate copolymer are described. In certain embodiments, the copolymer is a multiphase copolymer blend having one phase a glass transition temperature of about −5° C. to about −50° C. Methods of making the compositions of the invention are also described. Also articles, films and laminates made from the compositions are described.

First claim

What is claimed is:

1. A composition, comprising a biodegradable branched polymer blend formed by reactive blending of:
a. polylactic acid (PLA); and
b. a biodegradable polyhydroxyalkanoate (PHA) polymer having a glass transition temperature (Tg) of between −5° C. and −50° C. and a weight average molecular weight from 500,000 Daltons to 2,000,000 Daltons, wherein the PHA polymer is a copolymer of:
3-hydroxybutyrate and 4-hydroxybutyrate, wherein the content of 4-hydroxybutyrate in the PHA polymer is from about 25% to about 85% by weight of the PHA polymer;

wherein the copolymer of 3-hydroxybutyrate and 4-hydroxybutyrate is the sole PHA polymer in the polymer blend,
wherein the content of the PHA polymer in the biodegradable branched polymer blend is between about 3% and about 40% by weight of the blend, and
wherein the renewable carbon content of the biodegradable branched polymer blend is at least 95% by weight of the blend,
wherein the biodegradable branched polymer blend was formed by reactive blending of the PLA and the PHA polymer with a branching agent.

2. The composition of claim 1 , wherein the renewable carbon content of the biodegradable branched polymer blend is at least 99% by weight of the blend.

3. The composition of claim 1 , wherein the branching agent is selected from: dicumyl peroxide, t-amyl-2-ethylhexyl peroxycarbonate, 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-di(t-butylperoxy) hexane, 2,5-dimethyl-2,5-di(t-amyl peroxy) hexane, 2,5-bis(t-butylperoxy)-2,5-dimethylhexane, 2,5-dimethyl-di(t-butylperoxy)hexyne-3, di-t-butyl peroxide, benzoyl peroxide, di-t-amyl peroxide, t-butyl cumyl peroxide, n-butyl-4,4-bis(t-butylperoxy)valerate, 1,1-di(t-butylperoxy)-3,3,5-trimethyl-cyclohexane, 1,1-di(t-butylperoxy)cyclohexane, 1,1-di(t-amylperoxy)-cyclohexane, 2,2-di(t-butylperoxy)butane, ethyl-3,3-di(t-butylperoxy)butyrate, 2,2-di(t-amylperoxy)propane, ethyl-3,3-di(t-amylperoxy)butyrate, t-butylperoxy-acetate, t-amylperoxyacetate, t-butylperoxybenzoate, t-amylperoxybenzoate, and di-t-butyldiperoxyphthalate or combinations thereof.

4. The composition of claim 1 , wherein the PLA and the PHA polymer were reactively blended with a branching agent in the presence of a co-agent.

5. The composition of claim 4 , wherein the co-agent is diallyl phthalate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, diethylene glycol dimethacrylate, bis (2-methacryloxyethyl) phosphate, or combinations thereof.

6. The composition of claim 4 , wherein the co-agent is an epoxy-functional styrene-acrylic polymer, an epoxy-functional acrylic copolymer, an epoxy-functional polyolefin copolymer, an oligomer comprising a glycidyl group with an epoxy functional side chain, an epoxy-functional poly(ethylene-glycidyl methacrylate-co-methacrylate), or an epoxidized oil or combinations thereof.

7. The composition of claim 1 , wherein the content of 4-hydroxybutyrate (4HB) in the PHA polymer is from 30% to 65% by weight of the PHA polymer.

8. The composition of claim 1 , wherein the content of 4-hydroxybutyrate (4HB) in the PHA polymer is from 45% to 65% by weight of the PHA polymer.

9. The composition of claim 1 , wherein the PHA polymer comprises an amorphous rubber phase having no melting point.

10. A film or multilayer laminate comprising at least one film layer comprising the composition of claim 1 .

11. An article made with the laminate of claim 10 , wherein the film has a thickness of about 1 to about 2 microns.

12. The article of claim 11 , wherein the article is a bag, a packaging film or an agricultural mulch film.

13. A resin composition made from the composition according to claim 1 .

14. A finished article made by extrusion processing of the resin composition of claim 13 , wherein the article is an injection molded part, a thermoformed part, a film or a coating.

15. An article made with the composition of claim 1 , wherein the article is a foam, a woven or nonwoven fiber, or a thermoformed part.

16. A method of preparing a polylactic acid (PLA)/polyhydroxyalkanoate (PHA) polymer blend, comprising reactively blending in the presence of a branching agent,
a. polylactic acid (PLA); and
b. a biodegradable polyhydroxyalkanoate (PHA) polymer having a glass transition temperature (Tg) of between −5° C. and −50° C. and a weight average molecular weight from 500,000 Daltons to 2,000,000 Daltons, wherein the PHA polymer is a copolymer of:
3-hydroxybutyrate and 4-hydroxybutyrate, wherein the content of 4-hydroxybutyrate in the PHA polymer is about 25% to about 85% of the weight of the PHA polymer;
wherein the copolymer of 3-hydroxybutyrate and 4-hydroxybutyrate is the sole PHA polymer in the polymer blend;

wherein the content of the PHA polymer in the PLA/PHA polymer blend is from about 3% to about 40% by weight of the PLA/PHA polymer blend, and
wherein the renewable carbon content of the PLA/PHA polymer blend is at least 95% by weight of the PLA/PHA polymer blend;
thereby forming a PLA/PHA polymer blend.

Assignees

• Metabolix Inc
• Cj Cheiljedang Corp

Inventors

• Krishnaswamy Rajendra K
• Van Walsem Johan
• Peoples Oliver P
• Shabtai Yossef
• Padwa Allen R

Classifications

• C08L2205/02

  containing two or more polymers of the same C08L -group · CPC title

• C08J3/246 Primary

  Intercrosslinking of at least two polymers · CPC title

• C08L2207/02

  Heterophasic composition · CPC title

• C08L67/02 Primary

  Polyesters derived from dicarboxylic acids and dihydroxy compounds (C08L67/06 takes precedence) · CPC title

• C08L67/04

  Polyesters derived from hydroxycarboxylic acids, e.g. lactones (C08L67/06 takes precedence) · CPC title