Detail of "126990-35-0"

Reference

Dicyclopentyldialkoxysilanes

Dicyclopentyldialkoxysilanes. Shinohara, Toshio; Iwabuchi, Motoaki; Suzuki, Nobuyuki (Shin-Etsu Chemical Co., Ltd., Japan). Eur. Pat. Appl. EP 460590 A1 11 Dec 1991, 5 pp. DESIGNATED STATES: R: DE, FR, GB, IT. (European Patent Organization). CODEN: EPXXDW. CLASS: ICM: C07F007-18. APPLICATION: EP 91-109083 4 Jun 1991. PRIORITY: JP 90-146721 5 Jun 1990. DOCUMENT TYPE: Patent CA Section: 29 (Organometallic and Organometalloidal Compounds) Prepn. of dicyclopentyldimethoxysilane from 2 mol of cyclopentylmagnesium halide and 1 mol of tetramethoxysilane or by the reaction of 2 mol of cyclopentylmagnesium halide with 1 mol of SiCl4 to give dicyclopentyldichlorosilane which is then methoxylated by MeOH. Thus, cyclopentylmagnesium chloride, prepd. from 209 g cyclopentyl chloride and 48. 10026-04-7 and 126990-35-0 which are cas registry numbers of substances are two of reagents here.6 g magnesium turnings in THF, was added dropwise to 152 g of Si(OMe)4 in THF at 50°. Distn. provided 173 g of dicyclopentyldimethoxysilane. .

Influence of Ziegler-Natta Catalyst Regioselectivity on Polypropylene Molecular Weight Distribution and Rheological and Crystallization Behavior

Influence of Ziegler-Natta Catalyst Regioselectivity on Polypropylene Molecular Weight Distribution and Rheological and Crystallization Behavior. Chadwick, John C.; Van der Burgt, Frank P. T. J.; Rastogi, Sanjay; Busico, Vincenzo; Cipullo, Roberta; Talarico, Giovanni; Heere, Johannes J. R. (Dutch Polymer Institute (DPI), Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, Eindhoven 5600 MB, Neth.). Macromolecules, 37(26), 9722-9727 (English) 2004 American Chemical Society. 126990-35-0 and 7786-30-3 are cas registry numbers. These chemicals are also mentioned in this article. CODEN: MAMOBX. ISSN: 0024-9297. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) Fundamental implications of occasional secondary (2,1-) insertions in propene polymn. with different MgCl2-supported Ziegler-Natta catalysts are discussed, with ref. to the properties of the polymers obtained. The relatively narrow mol. wt. distribution of polypropylene prepd. using catalysts of type MgCl2/TiCl4/diether-AlR3 is ascribed to the fact that the active species in this system are relatively uniform, in the sense that significant 2,1-insertion takes place at both highly isospecific and weakly isospecific active species. In contrast, the isospecific species in the catalyst system MgCl2/TiCl4/diisobutyl phthalate-AlEt3-alkoxysilane undergo less 2,1-insertion and are therefore less responsive to chain transfer with hydrogen. The presence of (some) highly regiospecific active sites in such catalysts will therefore lead to the formation of a high mol. wt. polymer fraction and, overall, a broad mol. wt. distribution. The presence of high mol. wt. chains leads to relatively slow mol. relaxation and a more rapid onset of crystn. of the polymer from the melt, as evidenced by rheol. studies of polypropylenes prepd. using different catalysts and having different mol. wt. distributions. .