BIODEGRADABLE POLYESTER, METHOD FOR PRODUCTION THEREOF AND ARTICLES CONTAINING SAID POLYESTER Russian patent published in 2013 - IPC C08G63/00 C08G63/02 C08G63/06 C08G63/127 C08G63/16 C08G63/181 C08G63/91 C08L67/00 C08L67/02 C08L67/04 C09D167/00 B32B27/36 

FIELD: chemistry.

SUBSTANCE: invention relates to a biodegradable mixed aliphatic-aromatic polyester suitable for an extrusion coating, which contains links formed from at least a dicarboxylic acid and at least a diol, with long-chain branches, and substantially free from gel, characterised by shear viscosity of 800-1600 Pa*s, heat-resistance constant of less than 1.5*10^-4, melt strength of 2-4.5 g and ultimate elongation greater than 30. The biodegradable polyester can be obtained by reactive extrusion from a linear polyester precursor containing links formed by dicarboxylic acid and diol and having melt flow index from 5 g/10 min to 30 g/10 min and terminal unsaturation content of 0.1-1% mol/mol. The method is realised by adding peroxides, epoxides and carbodiimides. The invention also relates to a layered article consisting of at least a base and at least a first layer consisting of the polyester disclosed herein, an extensible film, multilayer films and a composition suitable for extrusion coating, which consists of a biodegradable mixed aliphatic-aromatic ester and polylactic acid.

EFFECT: obtaining biodegradable polyesters, having physical and chemical properties which enable to obtain thin films with high melt stability and high transparency.

21 cl, 7 dwg, 4 ex