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Methods for lowering melt viscosity and improving heat-sealability of polyester and for manufacturing heat-sealed container or package

Research output: PatentScientific


Original languageEnglish
Patent numberCN105934471
IPCB65D 65/ 38 A I
Priority date22/01/15
Publication statusPublished - 7 Sep 2016
Publication typeH1 Granted patent


The invention relates to methods for lowering the melt viscosity and thereby improving heat-sealability of a polyester. The invention also relates to a method for manufacturing a heat-sealed container or package from fibrous- based, polyester-coated packaging material, and a method for heat-sealing polyester. The solution according to the invention is subjecting polyester to electron beam (EB) radiation. The lowered melt viscosity allows a lower heat-sealing temperature, and permits sealing of polyester to an uncoated fibrous surface. The preferred polyester for the invention is polylactide, as such or as blended with another polyester.