POLY(ESTER-AMIDE) BLOCK COPOLYMER HOT MELT ADHESIVES

摘要

1340214 Block polyester-amides MONSANTO CO 14 June 1971 [15 June 1970] 27817/71 Heading C3R [Also in Division B5] A polyester-amide block copolymer containing 30 to 70 wt. per cent of crystalline polyester segments and 70 to 30% polyamide segments is the reaction product of (A) a crystalline polyester melting above 180‹ C. and of inherent viscosity 0À05 to 0À70 (on 0À5 g./100 ml. 60/40 phenol/tetrachloroethane at 25‹ C.) with (B) a polyamide of an aliphatic primary diamine and a C 18-54 polycarboxylic acid or mixture thereof with a linear aliphatic C 4-10 dibasic acid constituting up to 60 wt. per cent of its mixture. They may be prepared by heating (A) and (B) at or above the melting point of the polyester; the polyamide may have been formed in the presence of the polyester at a temperature below its melting point. The polyester may be a homopolyester of an alkylene glycol with terephthalic or naphthalic acid or a copolyester also containing units of another acid. Several suitable polyesters are exemplified. The C 18-54 polycarboxylic acid used to prepare the polyamide is obtained by polymerizing unsaturated fatty acids and may contain 80 to 100% dimer; various C 2-10 linear, branched- or cyclo-alkylene diamines and linear aliphatic diacids are mentioned as suitable co-reactants. The block copolymers are useful as hot melt adhesives resistant to flow at temperatures around 150‹ C.; They may have a crystalline melting point of 155‹ to 225‹ C., a melt viscosity at 220‹ C. of 5000 to 65,000 cp., and inherent viscosity of 0À35 to 0À85. They may be compounded with antioxidants, thermal stabilizers, fillers, extenders, dyes, pigments, adhesion promoters or plasticizers.