Polyhydroxyalkanoate copolymer/starch compositions for laminates and films
View Patent ↗Films comprising a blend of polyhydroxyalkanoate copolymer and destructured starch are disclosed. Laminates having a first layer comprising a PHA copolymer and a second layer comprising a PHA copolymer/starch blend or thermoplastic starch are also disclosed. Disposable articles comprising the environmentally degradable films or laminates are also disclosed.
1. A composition comprising:
destructured starch; and
a polyhydroxyalkanoate copolymer comprising at least two randomly repeating monomer units
wherein a first monomer unit has structure (I)
where R 1 is H, or C1 or C2 alkyl, and n is 1 or 2; and
wherein a second monomer unit has structure (II)
where R 2 is a C3–C19 alkyl or C3–C19 alkenyl,
or the second monomer unit has structure (III)
where m is from 2 to 9
wherein the composition is in the form of a film.
2. The composition of claim 1 wherein the polyhydroxyalkanoate copolymer comprises a third randomly repeating monomer having structure (IV):
where R 5 is H, or C1–C19 alkyl or alkenyl, and s is 1 or 2, with the proviso that the third monomer is not the same as the first or second monomer.
3. The composition of claim 1 further comprising a second polyhydroxyalkanoate polymer or copolymer.
4. The composition of claim 1 wherein the polyhydroxyalkanoate copolymer is present in an amount of from 25% to 99% by weight of the film.
5. The composition of claim 1 further comprising a plasticizer and wherein the polyhydroxyalkanoate copolymer is present in an amount of from 15% up to 99% by weight of the film.
6. The composition of claim 4 wherein the starch is present in an amount of from 1% to 75% by weight of the film.
7. The composition of claim 5 wherein the starch is present in an amount of from 1% to 85% by weight of the film.
8. A bag comprising the film of claim 1 .
9. A wrap comprising the film of claim 1 .
10. An absorbent article comprising the film of claim 1 .
11. A multilayer laminate film wherein at least one layer comprises the composition of claim 1 .
12. The multilayer laminate film of claim 11 wherein a second layer consists essentially of a PHA copolymer.
13. The multilayer laminate film of claim 11 wherein the at least one layer is an intermediate layer and the film further comprises two outer layers wherein the two outer layers consist essentially of a PHA copolymer.
14. A multilayer laminate film having at least one layer which comprises a composition of claim 1 or a thermoplastic starch, and having at least one layer which consists essentially of a polyhydroxyalkanoate copolymer comprising at least two randomly repealing monomer units
wherein a first monomer unit has structure (I)
where R 1 is H, or C1 or C2 alkyl, and n is 1 or 2; and
wherein a second monomer unit has structure (II)
where R 2 is a C3–C19 alkyl or C3–C19 alkenyl,
or the second monomer unit has structure (III)
where m is from 2 to 9.
15. The composition of claim 1 in the form of a stretched film having continuous pores that prevent penetration of liquid and that pass moisture vapor.
16. The composition of claim 1 further comprising dispersed particulate filler, the composition in the form of a stretched film having continuous pores that prevent penetration of liquid and that pass moisture vapor.
17. The multilayer laminate of claim 11 wherein the at least one layer further comprises dispersed particulate filler, the layer having been stretched to produce continuous pores that prevent penetration of liquid and that pass moisture vapor.
18. A composition comprising:
destructured starch; and
a polyhydroxyalkanoate copolymer comprising at least two randomly repeating monomer units
wherein a first monomer unit has structure (I)
where R 1 is H, or C1 or C2 alkyl, and n is 1 or 2; and
wherein a second monomer unit has structure (II)
where R 2 is a C3–C19 alkyl or C3–C19 alkenyl,
or the second monomer unit has structure (III)
where m is from 2 to 9
wherein the composition is in the form of a breathable film.
19. A composition produced by co-processing destructured starch; and
a polyhydroxyalkafloate copolymer comprising at least two randomly repeating monomer units
wherein a first monomer unit has structure (I)
where R 1 is H, or C1 or C2 alkyl, and n is 1 or 2; and
wherein a second monomer unit has structure (II)
where R 2 is a C3–C19 alkyl or C3–C19 alkenyl,
or the second monomer unit has structure (III)
where m is from 2 to 9.
20. A method of reducing environmental pollution comprising depositing in a solid-waste treatment facility or sanitary landfill an article comprising the composition of claim 1 wherein biodegradation of the article occurs more rapidly than biodegradation of articles not comprising the composition.
21. The method of claim 20 where the solid-waste treatment facility or sanitary landfill has an environment for anaerobic degradation.