| 摘要 |
<p>Diketene-contg. acrylonitrile copolymer prepn., by pptn. polymerisation in an aq. medium in the presence of Redox catalysts, takes place by (a) first using >=80 wt. % acrylonitrile and opt. 15 wt. % of copolymerisable ethylenically unsatd. monomer (I); (b) initiating polymerisation and then (c) polymerising the mixt. at 30-70 degrees C and pH 3-4 with the gradual addn. of 0.1-6 wt. % diketene. The copolymers can be spun to filaments and fibres. Prods. have a good colour and K-value 70-90. 80-90% Yields are obtd. quickly. Reactions at lactone ring allow polymer modification. Pref. (I) are Me acrylate, methallyl-sulphonic acid or its salts, acrylic acid or acrylamide.</p> |
