Reference

Pyridinyl-containing silane monomers and siloxane dimers and polymers

Pyridinyl-containing silane monomers and siloxane dimers and polymers. Zeldin, M.; Xu, J. M.; Tian, C. X. (Dep. Chem., Indiana Univ.-Purdue Univ., Indianapolis, IN 46223, USA). Polym. Prepr. (Am. Chem. Soc., Div. 108094-05-9 and 372-47-4 are cas registry numbers of chemicals which are used as reagents here. Polym. Chem.), 28(1), 417-19 (English) 1987. CODEN: ACPPAY. ISSN: 0032-3934. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) Hydrolysis of 2-fluoro-3-dimethyl- [108094-06-0] and 3-fluoro-4-dimethylchlorosilylpyridine [108093-98-7] which were prepd. from fluoropyridines with excess Me2SiCl2 [75-78-5] gave disiloxanes. 3-Methyldichlorosilylpyridine [108094-05-9] prepd. from 3-bromopyridine [626-55-1] with excess MeSiCl3 [75-79-6] was hydrolytically polymd. to give a hydroxy-terminated siloxane which, when refluxed with (Me3Si)2NH and Me3SiCl, was converted to a Me2Si-terminated siloxane. .

Hydrolytic polycondensation of organochlorosilanes at the liquid-gas interface

Hydrolytic polycondensation of organochlorosilanes at the liquid-gas interface. Kireev, V. V.; Vasil'eva, T. V.; Stakhanov, I. P.; Ignatov, V. A.; Kuprin, A. S.; Prikhod'ko, L. A.; Petrovnina, N. M. (Inst. Tonkoi Khim. Tekhnol. im. Lomonosova, Moscow, USSR). Dokl. Akad. Nauk SSSR, 290(4), 859-63 [Chem.] (Russian) 1986. CODEN: DANKAS. ISSN: 0002-3264. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) Hydrolytic polycondensation of MeSiCl3 [75-79-6] conducted by introducing gaseous MeSiCl3 in a mixt. with air into water resulted in formation of water-sol. hydroxyl-contg. oligomeric silsesquioxanes, in contrast to a 3-dimensional insol. polymer obtained by polymn. at the liq.-liq. interface. The amt. of the polymer formed was controlled by diffusion of MeSiCl3 vapors in the air bubble to the gas-liq. interface. Comparison of theor. and exptl. results showed that at contact times ￡0.7 s between the liq. and gaseous phase (i.e., time the length of which depended on the rate of ascending monomer-contg. air bubble in the layer of water), the diffusion coeff. reached a const. value and was equal to 0.0535 ± 0.007 cm2/s, and the diam. of the MeSiCl3 mol. was 7.9 ?. The activation energy of polymn. was 19.8 kJ/mol at 4-60°, height of the water layer through which the monomer-contg. bubbles had to pass 300 mm, and rate of feeding of the gaseous mixt. 280 mL/min. The yield of the oligomer and apparent coeff. of diffusion was virtually independent of the surface tension.