| 摘要 |
<p>Poly(tetramethylene ether) glycol (PTMEG) with terminal ester gps. or its copolymer is prepd. by: (A) reacting (1) tetrahydrofuran (THF) and opt. up to 50%, based on THF, of an alkyl THF of formula (I) (where one of R1-4 is 1-4C alkyl and the others are H), (2) an acylium ion precursor, (3) a catalyst comprising a polymer of ethylenically unsatd. monomers, contg. gp. (where is the polymer chain or segment, D is H, 1-10C aliphatic or aromatic hydrocarbon gp, halogen or a segment of the polymer chain, X and Y are H, halogen, 1-10C aliphatic or aromatic gp. or F >=1 being F, R is linear or branched bridging gp. contg. up to 40C in the main chain, and Z is H, halogen, 1-10C aliphatic or aromatic gp. or F), the polymer being free of functional gps. hindering the reaction, (4) opt. a 1-36C aliphatic carboxylic acid pref. acetic acid. The PTMEG ester is then sepd. from the reaction medium and can be hydrolysed with a base to give the glycol. The catalyst can be sepd. from the reaction medium after the reaction and reused.</p> |
