US 11,866,606 B2
Biodegradable coatings based on aqueous PHA dispersions
Joe B. Grubbs, III, Bishop, GA (US); Richard Eaton, Athens, GA (US); and Karson Durie, Athens, GA (US)
Assigned to Danimer IPCo, LLC, Bainbridge, GA (US)
Filed by Danimer IPCo, LLC, Bainbridge, GA (US)
Filed on Aug. 12, 2019, as Appl. No. 16/537,800.
Claims priority of provisional application 62/718,039, filed on Aug. 13, 2018.
Prior Publication US 2020/0048493 A1, Feb. 13, 2020
Int. Cl. C09D 167/04 (2006.01); C09D 7/65 (2018.01); C09D 7/61 (2018.01); C09D 7/45 (2018.01); C09D 7/63 (2018.01); B65D 65/42 (2006.01); B65D 65/46 (2006.01); C09D 5/14 (2006.01)
CPC C09D 167/04 (2013.01) [B65D 65/42 (2013.01); B65D 65/466 (2013.01); C09D 5/14 (2013.01); C09D 7/45 (2018.01); C09D 7/61 (2018.01); C09D 7/63 (2018.01); C09D 7/65 (2018.01)] 19 Claims
 
1. A biodegradable aqueous dispersion for coating food contact substrates, the dispersion comprising:
from about 35 to about 75 weight percent water;
from about 25 to about 65 weight percent of polyhydroxyalkanoates having a weight average molecular weight from about 50,000 Daltons to about 2.5 million Daltons;
from about 0.1 weight percent to about 5 weight percent of at least one nucleating agent;
from about 0.01 weight percent to about 5.0 weight percent of at least one surfactant;
from about 0.01 weight percent to about 5.0 weight percent of at least one rheology modifier;
from about 0.01 weight percent to about 2.5 weight percent of at least one wetting and dispersing agent; and
from about 0.01 weight percent to about 0.5 weight percent of at least one biocide or biostatic agent,
wherein the dispersion has an average solids content from about 25 percent to about 65 percent solids and
wherein the dispersion is prepared by
mixing water, the polyhydroxyalkanoates, the at least one surfactant, and the at least one wetting and dispersing agent to form a mixture comprising initial micelles of the polyhydroxyalkanoates,
homogenizing the mixture to form a dispersion, and
further adding the at least one nucleating agent, the at least one rheology modifier, and the at least one biocide or biostatic agent to the dispersion.