Back to results
US 5,252,642 AGranted
Degradable impact modified polyactic acid
AssigneeBioPak Technology, Ltd.
InventorsRichard G. Sinclair, Joseph Preston
Life of this patent
Estimating the term…
Abstract
An environmentally degradable composition comprises blends of a physical mixture of a poly(lactic acid), comprising about 1 to 99 weight percent of the composition, and an elastomeric blend compatible polymer, such as a segmented polyester, that provides improved impact resistance to the poly(lactic acid) and is discrete and intimately bound; plasticizer is added to the blend that is selected from the group consisting of lactide monomer, lactic acid oligomer, lactic acid, and mixtures thereof. Other plasticizer that may be added includes one or more derivatives of an oligomer of lactic acid, its esters and copolymer.
Claims31
A degradable composition comprising:
- blends of a physical mixture of:
- a. a poly(lactic acid);
- and
- b. a blend compatible polymer that provides improved impact resistance to the poly(lactic acid), wherein the polymer is selected from the group consisting of a block copolymer of hard crystalline segments of poly(butylene terephthalate) and soft long chain segments of poly(ether glycols), natural rubber, styrene-butadiene copolymers, and mixtures thereof;
- and
- wherein said poly(lactic acid) and said blend compatible polymer are present as discrete heterogeneous phases.
3 more elements
An environmentally degradable composition comprising blends of a physical mixture of:
- a) a poly(lactic acid) having a number average molecular weight greater than about 5,400;
- b) an elastomeric blend compatible polymer that provides an improved impact resistant composition, and the elastomeric blend compatible polymer is intimately bound into the poly(lactic acid) as a discrete heterogeneous phase;
- and
- c) a plasticizer selected from the group consisting of lactic acid, D-lactide, L-lactide, meso D,L-lactide, racemic D,L-lactide, oligomers of lactic acid, oligomers of lactide, and mixtures thereof, wherein the oligomers have a number average molecular weight below about 5,400, and wherein the plasticizer is intimately dispersed within at least the poly(lactic acid);
- wherein the elastomeric blend compatible polymer is selected from the group consisting of polyisoprene (gutta percha), styrene-isoprene-styrene block copolymers, acrylonitrile-butadiene-styrene block copolymers, styrene-ethylene-styrene block copolymers, propylene-ethylene-propylene block copolymers, propylene-isoprene-propylene block copolymers and mixtures thereof.
2 more elements
An environmentally degradable composition comprising blends of a physical mixture of:
- a) a poly(lactic acid) having a number average molecular weight greater than about 5,400;
- b) an elastomeric blend compatible polymer that provides an improved impact resistant composition, and the elastomeric blend compatible polymer is intimately bound into the poly(lactic acid) as a discrete heterogeneous phase;
- and
- c) a plasticizer selected from the group consisting of lactic acid, D-lactide, L-lactide, meso D,L-lactide, racemic D,L-lactide, oligomers of lactic acid, oligomers of lactide, and mixtures thereof, wherein the oligomers have a number average molecular weight below about 5,400, and wherein the plasticizer is intimately dispersed within at least the poly(lactic acid);
- wherein the elastomer blend compatible polymer is selected from polyurethanes that are not significantly water swellable or water soluble.
2 more elements
An environmentally degradable composition, comprising blends of a physical mixture of:
- a) a poly(lactic acid) having a number average molecular weight greater than about 5,400;
- b) an elastomeric blend compatible polymer that provides an improved impact resistant composition, and the elastomeric blend compatible polymer is intimately bound into the poly(lactic acid) as a discrete heterogeneous phase;
- and
- c) a plasticizer selected from the group consisting of lactic acid, D-lactide, L-lactide, meso D,L-lactide, racemic D,L-lactide, oligomers of lactic acid, oligomers of lactide, and mixtures thereof, wherein the oligomers have a number average molecular weight below about 5,400, and wherein the plasticizer is intimately dispersed within at least the poly(lactic acid);
- wherein the elastomeric blend compatible polymer is a block copolymer of hard crystalline segments of poly(butylene terephthalate) and soft long chain segments of poly(ether glycol).
2 more elements
A process for producing an environmentally degradable composition, comprising:
- a. providing a poly(lactic acid) having a number average molecular weight greater than about 5,400;
- b. providing a plasticizer selected from the group consisting of lactic acid, D-lactide, L-lactide, meso D,L-lactide, racemic D,L-lactide, and mixtures thereof;
- c. providing an elastomeric blend compatible polymer that provides an improved impact resistant composition in which the elastomeric blend compatible polymer is intimately bound into the poly(lactic acid) as a discrete heterogenous phase;
- and
- d. blending the polymers of steps (a) and (c) with the plasticizer of step (b);
- wherein the elastomeric blend compatible polymer is selected from the group consisting of polyisoprene (gutta percha), styrene-isoprene-styrene block copolymers, acrylonitrile-butadiene-styrene block copolymers, styrene-ethylene-styrene block copolymers, propylene-ethylene-propylene block copolymers, propylene-isoprene-propylene block copolymers and mixtures thereof.
3 more elements
A process for producing an environmentally degradable composition, comprising:
- a. providing a poly(lactic acid) having a number average molecular eight greater than about 5,400;
- b. providing a plasticizer selected from the group consisting of lactic acid, D-lactide, L-lactide, meso D,L-lactide, racemic D,L-lactide, and mixtures thereof;
- c. providing an elastomeric blend compatible polymer that provides an improved impact resistant composition in which the elastomeric blend compatible polymer is intimately bound into the poly(lactic acid) as a discrete heterogenous phase;
- and
- d. blending the polymers of steps (a) and (c) with the plasticizer of step (b);
- wherein the elastomeric blend compatible polymer is selected from polyurethanes that are not significantly water swellable or water soluble.
3 more elements
A process for producing an environmentally degradable composition, comprising:
- a. providing a poly(lactic acid) having a number average molecular weight greater than about 5,400;
- b. providing a plasticizer selected from the group consisting of lactic acid, D-lactide, L-lactide, meso D,L-lactide, racemic D,L-lactide, and mixtures thereof;
- c. providing an elastomeric blend compatible polymer that provides an improved impact resistant composition in which the elastomeric blend compatible polymer is intimately bound into the poly(lactic acid) as a discrete heterogenous phase, said elastomeric blend compatible polymer is selected from the group consisting of a block copolymer of hard crystalline segments of poly(butylene terephthalate) and soft long chain segments of poly(ether glycols), natural rubber, styrene-butadiene copolymers, and mixtures thereof;
- and
- d. blending the polymers of steps (a) and (c) with the plasticizer of step (b).
2 more elements
A process for producing an environmentally degradable composition, comprising:
- a. mixing one or more lactides selected from the group consisting of D-lactide, L-lactide, meso D,L-lactide, racemic D,L-lactide and mixtures thereof with an elastomeric blend compatible polymer that provides an improved impact resistant composition in which the elastomeric blend compatible polymer is intimately bound into the poly(lactic acid) as a discrete heterogenous phase, wherein the resulting composition is hydrophobic, nonporous, nonswellable in water, and hydrolyzes at the same rate or slower than the poly(lactic acid) alone;
- b. heating and dissolving the blend compatible polymer in the lactide(s) of step (a) to form a solution;
- c. polymerizing the lactide(s) in the solution to produce a poly(lactic acid) having a number average molecular weight greater than about 5,400;
- and
- d. incorporating into the polymerized lactides a plasticizer selected from the group consisting of lactic acid, D-lactide, L-lactide, meso D,L-lactide, racemic D,L-lactide, oligomers of lactic acid, oligomers of lactide, and mixtures thereof, wherein the oligomers have a number average molecular weight below about 5,400 and wherein the plasticizer is intimately dispersed within at least the poly(lactic acid).
2 more elements
The process of claim comprising stopping the polymerization prior to completion to provide residual monomer in the composition.
Dependencies are inferred from the claim text.