Absorbent articles comprising biodegradable polyester blend compositions

Abstract

The present invention relates to tough and ductile biodegradable, aliphatic polyester blend compositions and methods for preparing such compositions. It relates to products made out of such blend compositions, including, but not limited to, films, fibers, nonwovens, sheets, coatings, binders, foams and molded products for packaging. The products exhibit a desirable combination of high strength, ductility and toughness, while maintaining flexibility, biodegradability and compostability. The present invention further relates to absorbent articles (e.g., diapers, sanitary napkins, pantiliners, etc.) comprising a liquid pervious topsheet, a liquid impervious backsheet comprising a film comprising the polyester blend compositions of the present invention and an absorbent core positioned between the topsheet and the backsheet. The polyester blend of the present invention comprises: (a) a copolymer comprising two randomly repeating monomer units wherein the first randomly repeating monomer unit has the structure: 1 wherein R1 is H, or C1 or C2 alkyl, and n is 1 or 2. The second RRMU comprises at least one monomer selected from the group consisting of the structures (II) and (III): 2 wherein R2 is a C3-C19 alkyl or C3-C19 alkenyl, and 3 wherein m is from 2 to about 16; wherein at least about 50 mole % of the copolymer comprises RRMUs having the structure of the first RRMU of formula (I). and wherein the polyhydroxyalkanoate is present at a level of at least about 20%, by weight, of the total of the polyhydroxyalkanoate and the aliphatic ester polycondensate. 4 wherein R1 is H or a C1-2 alkyl and n is 1 or 2; and the second randomly repeating monomer unit has the structure: 5 wherein R2 is a C3-9 alkyl or alkenyl; and (b) an aliphatic ester polycondensate synthesized from an aliphatic polyhydric alcohol and an aliphatic polycarboxylic acid compound.

Dependencies are inferred from the claim text.