Patent ID: 9157877
Filing Date: 2015-10-13
Classification: G01N,Y10T

Abstract:
1. A process for characterizing a copolymer of ethylene and vinyl acetate (EVA) using a differential calorimetry analysis technique, wherein said process comprises the steps of: subjecting a sample of said EVA copolymer to a heat treatment, by temperature increases and decreases at constant rate, between a lower limit temperature of −80° C. and an upper limit temperature of 120° C., to obtain a thermogram, on the thermogram obtained, detecting a temperature zone corresponding to a crystallization temperature zone, determining a crystallization peak of the crystallization temperature zone by crossing of two straight lines tangent to a descending slope of a peak in the crystallization temperature zone and a shape factor of said peak, comparing said crystallization temperature zone and said crystallization temperature peak with a corresponding crystallization temperature zone and crystallization temperature peak on reference thermograms obtained from samples of EVA with known cross-linking densities, or with a corresponding temperature zone and crystallization temperature peak on thermograms of other samples obtained from samples of EVA with unknown cross-linking densities, wherein the reference thermograms and thermograms of other samples are obtained using the same heat treatment as the sample of EVA copolymer is subjected to, and determining at least one characteristic value of said sample of EVA copolymer selected from the group consisting of a degree of crosslinking of said sample and vinyl acetate content of said sample, based on said comparison.