BLOCK COPOLYMER

• Main Authors: ASAHARA ITSURO, TAKEMATSU MINORU
• Format: Patent
• Language: English
• Published: 19.04.1994
• Edition: 5
• Subjects: ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; ADHESIVES; CHEMISTRY; COMPOSITIONS BASED THEREON; DYES; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; POLISHES; THEIR PREPARATION OR CHEMICAL WORKING-UP; USE OF MATERIALS AS ADHESIVES

PURPOSE:To obtain the subject copolymer having a specific structure, exhibiting characteristics as a thermoplastic elastomer, free from change in melting viscosity in heat melting with the passage of time, excellent in heat stability and useful for a base polymer of heat-melting type tacky agent composition. CONSTITUTION:The objective copolymer consists of a block copolymer of formula I, formula II or formula III [S is polymer block of aromatic vinyl compound; B is butadiene polymer block; I is isoprene polymer block; (n) is 2-4; X is coupling residue]. This copolymer has 10000-500000 weight average molecular weight and contains 10-50wt.% aromatic vinyl compound, 10-60wt.% bound butadiene and 10-60wt.% bound isoprene, <15wt.% 1,2-vinyl bond and <=10wt.% 3,4-vinyl bond of isoprene part and has 10 to 3X10 Pa storage elastic modulus G' (at 0-50 deg.C) in measurement of viscoelasticity. In this copolymer, only one peak of dissipation factor tank owing to B and I exists at -80 deg.C to -50 deg.C.