| 摘要 |
The materials are of formula (1) are claimed. In (I) A (each the same) = simple valency bond, -O-. -C(:O)O-, or -OC(:O); B1 = -CH=N- or -N=CH-; B2 = N=CH- when B1 = -CH=N-, or -CH=N- when B1 = -N=CH-; D = aromatic gp. of formula (2) y = 0, 1, or 2; when y = 1, E = simple valency bond, -CH=N-, -N=CH, or azomethine gp. of formula (3) or (4), and when y = 2, E = simple valency bond or gp. of formula (3) or (4); R1-R6 = opt. branched 1-12C alkyl, opt. substd. by one or more Cl, Br, or CN; Ph opt. substd. by one or more 1-4C alkyl and/or 1-4C alkoxy or one or more Cl; x = integer of 2-8; n = integer or fraction of 1-5. Prepn. of (I) comprises (1) rearranging and cyclising thermotropic copolymer (II) repeating units of formula (5) (II) being as soln. of concn. less than 5 g% (sic)/100 cc in one or more solvents and soln. being stirred at 40-150 deg. C for time such that amt. of (I) no longer increases; (2) sepg. (II) according to solubility, by (i) distn. of solvent(s) under reduced w pressure followed, if necessary, when (I) is mixed with (II), by purifying (I) through selective pptn. using appropriate solvent system and/or recrystallisation;. or (ii) addn. of non-solvent(s) to cooled reaction soln., sepn. of ppt. of (I), and purification if required as in (i); or (iii) filtration of cooled reaction soln. if (I) is pptd. on forming, opt. followed by washing of ppt.. Opt. soln. of (II) contains appropriate amt(s). of (A) alpha, omega-bis(hydrogeno)diorganosiloxane (III) and/or (B) strong acid. USE - Where h1ghly organised materials are required.
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