USE OF POLYESTER RESINS FOR THE PRODUCTION OF ARTICLES HAVING GOOD PROPERTIES AS BARRIERS TO WATER VAPOUR

摘要

Polyester resins formed by recurring units X = [O-(CH2)n-OCO-(CH2)m-CO] and/or Y = [O-(CH2)k-CO], where the half-sum of n + m is equal to or greater than 6 and k is a number equal to or greater than 6, or by copolymers comprising units and/or sequences having the formula x i[O-(CH2)ni-OCO-(CH2)mi-CO]; y j[O-(CH2)kj-CO] where: i,j = 1-5; n i = 2-22; m i = 0-20; k j = 1=21; (Formula (1)) and x i and y j vary between 0 and 1 and are molar fractions of the various units such that (Formula (2)), are used for the preparation of products in which a permeability to water vapour of less than 350 gx30.mu.m/m2 per day, measured at 38 .degree.C and 90 % RH and good biodegradability are required.