ISSN:
0887-624X
Keywords:
addition polymerization
;
cyclosiloxanes
;
depolymerization
;
hexamethylcyclotrisiloxane
;
silyl perchlorates
;
decamethylcyclopentasiloxane
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Efforts to optimize the formation of the cyclic D5 oligomer (D = Me2SiO) of polydimethylsiloxane have led to the development of a new class of redistribution catalyst, the silyl perchlorates. Where as previous Lewis and Bronsted acid catalysts have transformed D3 almost exclusively into D3n oligomers, use of phenyldimethylsilyl perchlorate as the catalyst gives predominantly D4, D5, and other non-D3n oligomers. This redistribution reaction is particularly useful for obtaining large amounts of the difficulty available D5. Similar studies of D4 with variation of solvent and catalyst led to little redistribution. © 1993 John Wiley & Sons, Inc.
Additional Material:
3 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pola.1993.080310707
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