Poly(lactic acid) composition with improved impact resistance

Patent metadata

Field	Value
Publication number	US-9512311-B2
Application number	US-30512707-A
Country	US
Kind code	B2
Filing date	Jun 11, 2007
Priority date	Jun 16, 2006
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

The present invention relates to a poly(lactic acid) composition with improved impact resistance, comprising, by weight: 60% to 97% of poly(lactic acid) (PLA), and 3% to 40% of a mixture of compounds A and B in which A is a copolymer of ethylene and of an unsaturated monomer bearing at least one epoxide or carboxylic acid or carboxylic acid anhydride function, and optionally of alkyl (meth)acrylate, and B is a copolymer of ethylene and of alkyl (meth)acrylate, wherein said mixture having a wt % (A)/wt % (A+B) ratio of between 0.10 and 0.49. The present invention also relates to the manufacture of parts or objects using these compositions.

First claim

The invention claimed is:

1. A polylactic acid composition comprising, by weight:
60% to 97% of polylactic acid (PLA), and
3% to 40% of a mixture of compounds A and B in which:
A is an ethylene-methyl, ethyl, n-butyl or isobutyl (meth)acrylate-maleic anhydride terpolymer or an ethylene-methyl, ethyl, n-butyl or isobutyl (meth)acrylate-glycidyl methacrylate terpolymer,
B is a copolymer of ethylene and of methyl, ethyl, n-butyl or isobutyl (meth)acrylate, said mixture having a weight % (A)/weight % (A+B) ratio of between 0.15 and 0.40.

2. The composition as claimed in claim 1 , wherein A is ethylene and of methyl acrylate and of glycidyl methacrylate terpolymer.

3. The composition as claimed in claim 1 , wherein B is a copolymer of ethylene and of ethyl, n-butyl, or isobutyl acrylate.

4. The composition as claimed in claim 1 , wherein the weight % (A)/weight % (A+B) ratio of the mixture is between 0.20 and 0.30.

5. A process for preparing a polylactic acid composition comprising, by weight:
60% to 97% of polylactic acid (PLA), and
3% to 40% of a mixture of compounds A and B in which:
A is an ethylene-methyl, ethyl, n-butyl or isobutyl (meth)acrylate-maleic anhydride terpolymer or an ethylene-methyl, ethyl, n-butyl or isobutyl (meth)acrylate-glycidyl methacrylate terpolymer,
B is a copolymer of ethylene and of methyl, ethyl, n-butyl or isobutyl (meth)acrylate, said mixture having a weight % (A)/weight % (A+B) ratio of between 0.15 and 0.40, comprising the step of mixing of the PLA, A, and B by extrusion.

6. The process of claim 5 , wherein said extrusion step comprises:
mixing by extrusion of A and B in a first step, and then
mixing by extrusion of the product obtained from the first step with PLA.

7. A component or object obtained from a polylactic acid composition comprising, by weight:
60% to 97% of polylactic acid (PLA), and
3% to 40% of a mixture of compounds A and B in which:
A is a an ethylene-methyl, ethyl, n-butyl or isobutyl (meth)acrylate-maleic anhydride terpolymer or an ethylene-methyl, ethyl, n-butyl or isobutyl (meth)acrylate-glycidyl methacrylate terpolymer,
B is a copolymer of ethylene and of methyl, ethyl, n-butyl or isobutyl (meth)acrylate, said mixture having a weight % (A)/weight % (A+B) ratio of between 0.15 and 0.40, wherein the component or object is prepared via a process chosen from molding, extrusion and thermoforming.

8. The component or object as claimed in claim 7 , whose preparation also comprises an annealing step.

9. The component or object of claim 7 , wherein said component comprises a multilayer structure further comprising at least one layer of a thermoplastic chosen from polyethylene (PE), polypropylene (PP), polystyrene (PS), polyamide (PA) and ethylene/vinyl alcohol (EVOH) copolymer.

10. A polylactic acid composition comprising, by weight:
60% to 97% of polylactic acid (PLA), and
3% to 40% of a mixture of compounds A and B in which:
A is an ethylene-methyl, ethyl, n-butyl or isobutyl (meth)acrylate-maleic anhydride terpolymer or an ethylene-methyl, ethyl, n-butyl or isobutyl (meth)acrylate-glycidyl methacrylate terpolymer,
B is a copolymer of ethylene and of methyl, ethyl, n-butyl or isobutyl (meth)acrylate, said mixture having a weight % (A)/weight % (A+B) ratio of between 0.25 and 0.40.

Assignees

• Fine Thomas
• Khusrawy Maliha
• Arkema France

Inventors

• Fine Thomas
• Khusrawy Maliha

Classifications

• Y10T428/31797

  Next to addition polymer from unsaturated monomers · CPC title

• Y10T428/31786

  Of polyester [e.g., alkyd, etc.] · CPC title

• B29C48/78

  Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling · CPC title

• B29C51/00

  Shaping by thermoforming {, i.e. shaping sheets or sheet like preforms after heating}, e.g. shaping sheets in matched moulds or by deep-drawing; Apparatus therefor {(blow moulding of tubular preforms B29C49/00, deforming of tubular or hollow preforms B29C67/0014)} · CPC title

• B29C48/361

  with the barrel or with a part thereof rotating · CPC title