| 摘要 |
Room temp. stable spinning dopes of optically active 4-methyl-azetidinone-2-(co)polymers or blends (A), for spinning into filaments/fibres/foils with higher temp. stability than obtainable from the racemates are prepd. by dissolving (A) in a mixture, liquid below 50 degrees C, consisting of (1) 15-25 wt.% di- and/or tri-chloracetic acid (B), where min. amount (B) increases to upper range limit with increasing average mol. wt. of (A); and (2) >15 wt.% of at least one solvent such as halo(alkyl)benzenes, halogenated 1-3C aliphatic hydrocarbons, ClCH2COOH, CF3COOH or HCOOH, in an amount such as to give a falling sphere viscosity of 30-800 falling sphere secs., (measured as falling time of steel balls of 1/8" at 20 cm. vertical distance and 20 degrees C according to DIN 5401) Uses include sewing threads for automatic sewing machines, and textiles with high affinity to anionic dyes. |
