Detail of "546-45-2"

Reference

Polymerization of organocyclosiloxanes in the presence of ionic fluorides

Polymerization of organocyclosiloxanes in the presence of ionic fluorides. Tartakovskaya, L. M.; Kopylov, V. M.; Zhdanov, A. A. (Inst. Elementoorg. Soedin. im. Nesmeyanova, Moscow, USSR). Vysokomol. Soedin., Ser. B, 26(3), 234-8 (Russian) 1984. CODEN: VYSBAI. ISSN: 0507-5483. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) The activity of ionic fluorides in catalyzing polymn. of organocyclosiloxanes depends on the cation of the former and structure of the latter, decreasing in the sequence: Me4NF [373-68-2] u Bu4NF×2H2O [429-41-4] > CsF > KF and 2,4,6-trimethyl-2,4,6-triphenylcyclotrisiloxane (I) [546-45-2] > hexamethylcyclotrisiloxane [541-05-9] > octamethylcyclotetrasiloxane (II) [556-67-2]. The activity of the fluorides increased in the presence of DMF [68-12-2]. Kinetics of polymn. of II in the presence of Me4NF was 1st order in II and 2nd order in Me4NF. The 2nd order in the catalyst was attributed to formation of an intermediate complex of a hexacoordinated Si atom of II and 2 mols. of Me4NF. Chromatog. anal. of the polymn. products of I and II indicated the occurrence of depolymn. in the course of polymn. (e.g., formation of methylphenylcyclotetrasiloxanes in polymn. of I). The presence of residual KF and CsF in the polymers catalyzed their oxidative thermal degrdn. The absence of such an effect by Me4NF and Bu4NF was attributed to their decompn. at elevated temps.

Determination of the silicon-hydrogen group in organosilicon compounds by infrared spectroscopy

Determination of the silicon-hydrogen group in organosilicon compounds by infrared spectroscopy. Krasikova, V. M.; Klimov, L. A.; Nikolaev, G. A. (All-Union Sci. Res. Inst. Synth. Rubber, Leningrad, USSR). Zh. Anal. Khim., 32(1), 127-32 (Russian) 1977. CODEN: ZAKHA8. DOCUMENT TYPE: Journal CA Section: 38 (Elastomers, Including Natural Rubber) Section cross-reference(s): 80 The content of SiH group in 1,3,3,5,5,7,7-heptamethylcyclotetrasiloxane, 1,5-dimethyl-3,3,7,7-tetraphenylcyclotetrasiloxane [51439-95-3], 1,3,3,5,7,7-hexaphenylcyclotetrasiloxane [62857-85-6], octaphenylcyclotetrasiloxane [546-56-5], 1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane [546-45-2], octamethylcyclotetrasiloxane [556-67-2], a mixt. of linear and cyclic siloxanehydrides, and polysiloxanes contg. dimethyl-, methylphenyl-, or diphenylsiloxane segments was detd. by measuring the absorption intensity of IR spectra at 2142-64 cm-1. The limit of detection is 1.5 x 10-2 mass%.