| 摘要 |
PROBLEM TO BE SOLVED: To provide a copolyester which has high hygroscopicity and can be easily formed into chips. SOLUTION: This composition comprises a polyester prepared by copolymerizing a polyoxyalkylene glycol and 0.01-30mol% crosslinking agent represented by the formula: (R2 O)m R1 (COOR3 )n (wherein R1 is a tetra- to hexa-valent organic residue; R2 is hydrogen or acetyl; R3 is hydrogen or an alkyl; and 3<=m+n<=6) and satisfies the following requirements: (a) the moisture absorption and release parameter (ΔMR) is 12.0% or above, (b) the melting peak ascribable to the polyoxyalkylene glycol of the polymer stands at 30 deg.C or above, and (c) the melt viscosity of the polymer is 500-5,000P as measured at 280 deg.C and a shear rate of 50cm<-1> .
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