| 摘要 |
(I) Liq. polythioethers contg. no oxygen in the polymeric backbone which are non-crystallising and water and fuel resistant and have the formula (I). In (I), each of R2 and R3 = H or lower alkyl each of R1 and R4 = lower alkyl R = lower alkylene or lower alkyl thioether p = 0-3; n = 8 -200; r = 0 or 1; a = 0 or 1; m = 1,3 or 4; when m = 1, r = 1; when m = 3 or 4, a = 1; Ri = an organic divalent radical having no chemically reactive gps. of an organic prim. dimercaptan Ri-(SH)2 each mercaptan gp. being prim. and Rii= a tri- or tetra-valent organic fragment having no chemically reactive gps. of the cpd. Rii- (Z)q where Z = a sec. OH located beta to a sulphur atom or mercaptan gp. and q = 3 or 4 are new. - Prepn. of liq. polythioethers, which are non-crystallising, are water and fuel resistant and have mol.wt. 900-25,000 by heating is also disclosed. |
