Synthesis of polycarbosilanes having a five‐membered cyclic carbonate structure and their application to prepare gel polymer electrolytes for lithium ion batteries

Abstract

A silacyclobutane having a five‐membered cyclic carbonate structure (SBMC) was prepared, and its transition metal‐catalyzed ring‐opening polymerization at the four‐membered carbosilane unit was investigated as well as formation of carbosilane networked polymers and polymer gel electrolytes. The SBMC was synthesized by epoxidation of 1‐(4‐butenyl)‐1‐methylsilacyclobutane followed by insertion of CO2 to the epoxide. Ring‐opening polymerization of the silacyclobutane moiety in the SBMC readily proceeded by a transition metal catalyst such as platinum divinyltetramethyldisiloxane complex. A flexible networked polymer film was obtained by copolymerization of the SBMC with a small amount of crosslinker, hexamethylene‐1,6‐bis(1‐methylsilacyclobutane) (HMBS). The copolymerization of SBMC and HMBS in 1 M LiPF6 solution in ethylene carbonate and diethyl carbonate (3/7 v/v) gave a gel polymer electrolyte, which showed good ionic conductivity and could be applied to lithium ion batteries. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

Polymerization of an epoxy‐containing silacyclobutane and its application to networked polymer synthesis

“…Because the Karstedt catalyst was reported to be effective for ring‐opening polymerization of various silacyclobutane derivatives, four‐membered ring‐opening polymerization of OBMSB was first examined by heating a toluene solution of OBMSB in the presence of 0.1 mol % of Karstedt catalyst (platinum vinylsiloxane complex) at 70 °C (Scheme ). The polymerization proceeded smoothly and the monomer was quantitatively consumed within 1 h, which was checked by 1 H NMR measurement of the crude reaction mixture.…”

“…1‐(3,4‐epoxybutyl)‐1‐methylsilacyclobutane (OBMSB) and DESB were prepared according to the reported procedure . Karstedt catalyst, platinum(0)‐1,3‐divinyl‐1,1,3,3‐tetramethyldisiloxane complex (solution in xylenes, ∼2% Platinum) was purchased from Aldrich (WI) and used as delivered.…”

“…We consider that they can be innovative key polymers in various advancing usages. Recently, we reported the synthesis of polycarbosilanes having 5‐membered cyclic carbonate groups and their application to gel polymer electrolytes for lithium ion batteries . The corresponding polymers were obtained by ring‐opening polymerization of a silacyclobutane monomer (SMBC), which had a 5‐membered cyclic carbonate group on the silicon atom.…”

“…The corresponding polymers were obtained by ring‐opening polymerization of a silacyclobutane monomer (SMBC), which had a 5‐membered cyclic carbonate group on the silicon atom. This monomer was prepared in two steps from 1‐(3‐butenyl)‐1‐methylsilacyclobutane via a silacyclobutane having an epoxy group (OBMSB; Scheme ) …”

Synthesis of an aliphatic hyper-branched polycarbonate and determination of its physical properties for solid polymer electrolyte use

“…Recently, polymers with the same structures as liquid electrolytes (carbonate compounds), such as polycarbonates, have attracted much attention because of their promising potential as SPEs. Several linear -4 -polycarbonates have been synthesized for the development of high-ionic-conductivity SPEs using polycarbonates [12][13][14][15][16][17][18][19][20][21][22][23][24]. For example, Shriver and Wei used poly (vinylene carbonate) as an SPE [12].…”