Polymers of carbonic acid, 21. Ring‐opening polymerization of cyclobis(diethylene glycol carbonate) by means of BuSnCl₃, SnOct₂ or Bu₂SnO as catalysts

Abstract

Cyclobis(diethy1ene glycol carbonate), (DEGC),, was synthesized by polycondensation of diethylene glycol with diethyl carbonate followed by thermal depolymerization of the crude polycarbonate in vacuo. BuSnCl,-initiated polymerizations of (DEGC)2 in chlorobenzene at 100 "C gave poor results. Therefore, all further polymerizations were conducted at 145°C in bulk. Two series of polymerizations were performed with BuSnC1, as catalyst, so that either the time was varied at constant monomerhitiator ( M / I) ratio, or the M/I ratio at constant time. Two analogous series were conducted with SnOct2. With both catalysts high yields but only moderate molecular weights were obtained. SnOct, yielded polycarbonates having octoate end-groups, which were detected by 'H NMR spectroscopy. (DEGQ2 was also polymerized with Bu2Sn0 at M/I = 200 or 500 with variation of time. The highest yields and molecular weights were obtained at the shortest time, whereas longer times caused rapid depolymerization. Therefore, Bu2Sn0 appeared to be the most reactive catalyst. Both 'H and I3C NMR spectra proved that all poly(diethy1ene glycol carbonates) prepared in this work possess an alternating sequence of ether and carbonate groups.

Carbonate-linked poly(ethylene oxide) polymer electrolytes towards high performance solid state lithium batteries

“…The reaction mixture was preheated to 120 C and the byproduct ethanol was evaporated and gradually removed within 10 h. The reaction temperature was raised and kept at 150 C for 2 h and then at 190 C for other 2 h [54,55]. After cooling to room temperature, the solid reaction mixture was dissolved in 75 mL CH 2 Cl 2 and washed with 25 mL 1 M HCl once and 25 mL distilled water three times.…”

“…Moreover, poly (ethylene carbonate) and poly(vinylene carbonate) electrolytes possessing short ethylene oxide (EO) side chains were also reported and both revealed that longer side chains favored better ionic conductivity [52,53]. Poly(diethylene glycol carbonate) was also developed and their sodium ion conducting properties was briefly studied [54,55]. To the best of our knowledge, the polycarbonate owning longer EO units into the main chains have not been discussed yet.…”

Lipase-catalyzed ring-opening polymerization and copolymerization of cyclic dicarbonates

“…A similar behavior was observed in the lipase-catalyzed polymerization of lactones 19) and 6-membered cyclic carbonate 17) . The polymer structure was confirmed by 1 H and 13 C NMR spectroscopy 4,5) . 13 C NMR spectrum of poly(1 b) shows three large peaks of the diethylene glycol carbonate unit at d = 67.0, 68.9, and 155.1 and a small peak at d = 61.7 due to a-methylene carbon of the terminal hydroxy group.…”

“…In using tin compounds as catalyst, high temperature (F 140 8C) was required for the production of the polymer with high molecular weight 4,5) . On the other hand, the lipase catalysis induced the polymerization of Ring-opening polymerization of cyclic dicarbonates, cyclobis(hexamethylene carbonate) (1 a) and cyclobis-(diethylene glycol carbonate) (1 b), and their copolymerization with lactones have been carried out using lipase as catalyst.…”

“…Six-and seven-membered cyclic carbonates were subjected to ringopening polymerization by various catalysts. Recently, the polymerization of cyclic dicarbonates, cyclobis(hexamethylene carbonate) 4) (1 a) and cyclobis(diethylene glycol carbonate) 5) (1 b) catalyzed by tin compounds was reported. During the polymerization, the elimination of carbon dioxide was not observed, yielding the corresponding polycarbonates.…”