BIODEGRADABLE CONTAINERS AND RESIN THEREFOR
A biodegradable preform, biodegradable containers and a method for making the plastic containers. The biodegradable container wherein the body of the container includes from about 40 to about 99 weight percent of a polymer derived from random monomeric repeating units having a structure of wherein R 1 is selected from the group consisting of CH 3 and a C 3 to C 19 alkyl group. The monomeric units wherein R 1 is CH 3 is about 75 to about 99 mol percent of the polymer. A resin adapted for forming the container is also disclosed.
1 . A resin adapted for forming a biodegradable container having a body and a closure therefor, the resin comprising:
from about 0.1 to about 10 weight percent of at least one nucleating agent;
from about 0.05 to about 3 weight percent of at least one melt strength enhancer; and
from about 40 to about 99 weight percent of a polymer derived from random monomeric repeating units having a structure of
wherein R 1 is selected from the group consisting of CH 3 and a C 3 to C 19 alkyl group, wherein the monomeric units wherein R 1 ═CH 3 comprise 75 to 99 mol percent of the polymer.
2 . The resin of claim 1 , wherein the resin comprises from about 40 to about 99 weight percent of poly(hydroxyalkanoate) copolymer and from about 1 to about 60 wt. % additional additives.
3 . The resin of claim 2 wherein the poly(hydroxyalkanoate) copolymer comprises poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (P3HB-co-P3HHx).
4 . The resin of claim 1 , wherein the resin further comprises from about 1.0 to about 15.0 weight percent of at least one poly(hydroxyalkanoate) comprising from about 25 to about 50 mole percent of a poly(hydroxyalkanoate) selected from the group consisting of poly(hydroxyhexanoate), poly(hydroxyoctanoate), poly(hydroxydecanoate), and mixtures thereof.
5 . The resin of claim 1 , wherein the resin further comprises a poly(hydroxyalkanoate)s terpolymer made up from about 75 to about 99.9 mole percent monomer residues of 3-hydroxybutyrate, from about 0.1 to about 25 mole percent monomer residues of 3-hydroxyhexanoate, and from about 0.1 to about 25 mole percent monomer residues of a third 3-hydoxyalkanoate selected from the group consisting of poly(hydroxyhexanoate), poly(hydroxyoctanoate), poly(hydroxydecanoate), and mixtures thereof.
6 . The resin of claim 1 , wherein the resin comprises poly(hydroxyalkanoate)s having a weight average molecular weight from about 50 thousand Daltons to about 2.5 million Daltons.
7 . The resin of claim 1 , wherein the resin further comprises from about 0.1 weight percent to about 10 weight percent of at least one nucleating agent selected from the group consisting of erythritols, pentaerythritol, dipentaerythritols, artificial sweeteners, stearates, sorbitols, mannitols, inositols, polyester waxes, nanoclays, polyhydroxybutyrate, boron nitride, and mixtures thereof.
8 . The resin of claim 1 , wherein the resin further comprises from about 0.05 weight percent to about 3 weight percent at least one melt strength enhancer selected from the group consisting of a multifunctional epoxide; an epoxy-functional, styrene-acrylic polymer; an organic peroxide; an oxazoline; a carbodiimide; and mixtures thereof.
9 . The resin of claim 1 , wherein the resin further comprises from about 1 weight percent to about 60 weight percent of polymers selected from the group consisting of poly(lactic acid), poly(caprolactone), poly(ethylene sebicate), poly(butylene succinate), and poly(butylene succinate-co-adipate), and copolymers and blends thereof.
10 . The resin of claim 1 , wherein the resin further comprises from about 0.1 weight percent to about 5 weight percent of a reheat agent selected from the group consisting of carbon black, infrared absorbing pigments, and mixtures thereof.
11 . The resin of claim 1 , wherein the resin further comprises from about 0.1 weight percent to about 20 weight percent of a filler selected from the group consisting of calcium carbonate, talc, starch, zinc oxide, neutral alumina, and mixtures thereof.
12 . The resin of claim 1 , wherein the resin further comprises from about 0.1 weight percent to about 5 weight percent polymer fibers for structural support.
13 . The resin of claim 1 , wherein the resin further comprises from about 0.1 weight percent to about 3 weight percent of a fatty acid amide slip agent.
14 . The resin of claim 1 , wherein the resin further comprises up to about 15 weight percent of a plasticizer selected from the group consisting of sebacates; citrates; fatty esters of adipic acid, succinic acid, and glucaric acid; lactates; alkyl diesters; alkyl methyl esters; dibenzoates; propylene carbonate; caprolactone diols having a number average molecular weight from about 200 to about 10,000 g/mol; poly(ethylene) glycols having a number average molecular weight of about 400 to about 10,000 g/mol; esters of vegetable oils; long chain alkyl acids; adipates; glycerols; isosorbide derivatives or mixtures thereof; poly(hydroxyalkanoate) copolymers comprising at least 18 mole percent monomer residues of hydroxyalkanoates other than hydroxybutyrate; and mixtures thereof.
15 . The resin of claim 1 , wherein the resin undergoes degradation according to ASTM D5511 (anaerobic and aerobic environments), ASTM 5988 (soil environments), ASTM D5271 (freshwater environments), ASTM D6691 (marine environments), ASTM D6868, or ASTM D6400 for industrial and home compostability (in soil).
16 . The resin of claim 1 , wherein the resin has a moisture vapor transmission rate of about 20 g/m 2 /day or less as measured under ASTM E96.