THERMOPLASTISCHE FORMMASSE UND VERFAHREN ZU IHRER HERSTELLUNG.

摘要

Thermoplastic moulding compsn. contains w.r.t. (A+B), (A) 80-60 (wt.)% rigid polystyrene matrix and (B) 20-40% soft phase, obtd. by polymerising styrene in the presence of a linear styrene-butadiene block copolymer with indistinct transition, which contains 35-45% styrene and 65-55% butadiene with a block polystyrene content of 25-35%. (B) is uniformly distributed in (A) and has a particle dia. of less than 0.8 micron. The average particle dia., d50 value (by vol.) of (B) is 0.252-0.38 micron, the particle size distribution range (d95-d5) value, is 0.2-0.6 micron, the d60 value, is in the 0.26-0.40 micron range and the d90 value is 0.40-0.75. (B) pref. contains 38-42% styrene and 62-58% butadiene with 25-35, esp. 30-32% block polystyrene. The average mol.wt. of (B) is 180000-250000 and the mol.wt. of the styrene block 50000-70000.