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没事在scifinder上查了下这个结构,还真有文献报道,不过看起来不是特别靠谱
The cohydrolysis of Me2SiCl2 and Ph2SiCl2 in Et2O at 35 gave 1,1-diphenyl-2,2,3,3,4,4-hexamethylcyclotetrasiloxane(I), b3 146-50, d20 1.0650, n20D 1.4895, MRD 114.22 and 2 isomers: 1,1,2,2-tetraphenyl-3,3,4,4-tetramethylcyclotetrasiloxane(II), m. 72, and 1,1,3,3-tetraphenyl - 2,2,4,4 - tetramethylcyclotetrasiloxane(III), m. 126. The polymn. of I and II carried out at 80 in the presence of 0.01% Me4NO[Si(Me)2O]2NMe4 resulted in polymers of a const. sp. viscosity (.apprx.0.3) after 70 min. During the polymn. of III, a const. sp. viscosity of .apprx.0.1 was achieved as soon as 15 min., possibly due to steric hindrance of bulky Ph groups. Optimum polymn. temp. was 80-90 for I. At 100 and esp. at 115 a drop in viscosity was observed after 1 hr. The yield of the polymer was substantially unaffected by temp. at 80-100. Mol. wt. distribution of I with mol. wt. 112,000 was also studied; viscosity [.eta.] = 2.25 10-4 (mol. wt.)0.604.
Polymerization of mixed diphenyldimethylcyclosiloxanes. Andrianov, K. A.; Yakushkina, S. E.; Guniava, L. N. Inst. Elementoorg. Compds., Moscow, USSR. Vysokomolekulyarnye Soedineniya (1966), 8(12), 2166-70. CODEN: VMSDA8 ISSN: 0042-9368. Journal written in Russian. CAN 66:76370 AN 1967:76370 CAPLUS |
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