# US 5,346,967 A · Blends of thermoplastic polyester resins and amorphous polyamides > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,346,967 A - Document ID: US5346967A - Status: Granted - Kind: A - Application number: 08/008,267 - Filed: 1993-01-25 - Granted: 1994-09-13 - Earliest claimed: 1987-11-04 - Assignees: General Electric Company - Inventors: Donald C. Clagett; Daniel W. Fox; Louis M. Maresca - Web page: https://patentgrep.com/patent/US5346967A ## CPC - C08L 77/00: Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain (of polyhydrazides C08L79/06; of polyamideimides or polyamide acids C08L79/08); Compositions of derivatives of such polymers - C08L 67/02: Polyesters derived from dicarboxylic acids and dihydroxy compounds (C08L67/06 takes precedence) - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) ## Abstract Thermoplastic resins of enhanced solvent resistance especially useful for packaging or automotive parts comprising blends of amorphous polyamides with a thermoplastic polyester resin, substantially free of a polyarylate have excellent physical properties and barrier resistance to oxygen and carbon dioxide. Preferred blends comprise polyesters prepared by reacting a dihydric alcohol with a dicarboxylic acid, and amorphous polyamides prepared from non-symmetric monomers comprising odd-number chain diamines and diacids, and meta aromatic diamines and diacids. ## Claims ### Claim 1 A method for enhancing the barrier resistance of a molded article to oxygen and carbon dioxide consisting of (a) blending a composition consisting entirely of a thermoplastic polyester resin having an intrinsic viscosity of from about 0.4 to about 2.0 dl/g as measured in a 60:40 phenol:tetrachlorethane mixture at 23.degree.-30.degree. C. containing less than 2% of wholly aromatic resin moieties and an effective barrier-resistance-improving amount of an amorphous polyamide resin; and (b) molding said blend into an article of specific dimensions by extrusion or injection molding. ### Claim 2 (depends on 1) A method as defined in claim 1 wherein said blend comprises from about 2 to about 98 percent by weight of said polyester resin and from about 98 to about 2 percent by weight of said amorphous polyamide. ### Claim 3 (depends on 2) A method as defined in claim 2 wherein said blend comprises from about 10 to about 90 percent by weight of said polyester resin and from about 90 to about 10 percent by weight of said amorphous polyamide. ### Claim 4 (depends on 1) A method as defined in claim 1 wherein said amorphous polyamide has no distinct melting point. ### Claim 5 (depends on 1) A method as defined in claim 1 wherein said amorphous polyamide has a heat of fusion of about 1 cal/gram or less. ### Claim 6 (depends on 1) A method as defined in claim 1 wherein said amorphous polyamide has side chain substitution. ### Claim 7 (depends on 1) A method as defined in claim 1 wherein said amorphous polyamide is polymerized from monomers comprising non-symmetric monomers. ### Claim 8 (depends on 7) A method as defined in claim 7 wherein said non-symmetric monomers comprise odd-numbered chain diamines and diacids, and meta aromatic diamines and diacids. ### Claim 9 (depends on 1) A method as defined in claim 1 wherein said amorphous polyamide is a copolymer of at least two nylons selected from the group consisting of nylon 6, 6/6, 11, 12, 6/3, 4/6, 6/4, 6/9, 6/10 and 6/12. ### Claim 10 (depends on 1) A method as defined in claim 1 wherein said polyester comprises units derived from a dihydric alcohol. ### Claim 11 (depends on 16) A method as defined in claim 16 wherein said polyester comprises units derived from ethylene glycol, 1,4-butanediol, polybutylene oxide diol, 1,4-cyclohexanedimethanol or a mixture of any of the foregoing. ### Claim 12 (depends on 1) A method as defined in claim 1 wherein said polyester comprises units derived from terephthalic acid, isophthalic acid, or a mixture thereof. ### Claim 13 A method for enhancing the barrier resistance of a molded article to oxygen and carbon dioxide consisting of (a) blending a composition consisting entirely of a thermoplastic polyester resin having an intrinsic viscosity of from about 0.4 to about 2.0 dl/g as measured in a 60:40 phenol:tetrachlorethane mixture at 23.degree.-30.degree. C. containing less than 2% of wholly aromatic resin moieties and an effective barrier-resistance-improving amount of an amorphous polyamide resin; and (b) molding said blend into a film or sheet product. ### Claim 14 A method for enhancing the barrier resistance of a molded article to oxygen and carbon dioxide consisting of (a) blending a composition consisting entirely of a thermoplastic polyester resin having an intrinsic viscosity of from about 0.4 to about 2.0 dl/g as measured in a 60:40 phenol:tetrachlorethane mixture at 23.degree.-30.degree. C. containing less than 2% of wholly aromatic resin moieties and an effective barrier-resistance-improving amount of an amorphous polyamide resin; and (b) injection molding said blend into an article.