Polymers of carbonic acid 18: polymerizations of cyclobis(hexamethylene carbonate) by means of BuSnCl3 or Sn(II)2-ethylhexanoate

Highly efficient enzymatic catalysis for cyclocarbonate polymerization

“…Nevertheless, the behavior was different from that of POMC and PDMC (containing 8 and 10 methylene groups per unit), in which the weight loss involves two steps. [38][39][40][41] Another marked disparity is the existence of carbon residue (5-7% weight%) after the thermal decomposition of POMC and PDMC, whereas there was no residue in the case of PTeMC, PHMC [38][39][40][41] and PPMC in this study. It is clear that the thermal decomposition of poly(alkylene carbonate)s may not all follow the same mechanism, and the chemical structure exerts a significant influence on their thermal stability and decomposition mechanism.…”

“…Together with the latent catalyst toxicity, these shortcomings limit the practical application of the Sn(Oct) 2 -catalyzed preparative method. [38][39][40][41] The important role of biosynthetic pathways, such as enzymatic polymerization, has been accepted in the fabrication of biomaterials. Nevertheless, the low catalytic efficiency is known to be the greatest limitation in the industrialization of enzyme catalysis.…”

Lithium chloride as catalyst for the ring-opening polymerization of lactide in the presence of hydroxyl-containing compounds

“…1,2 A variety of catalysts have been documented in the literature, including stannous octoate, [3][4][5] alkali-metal hydrides or alkoxides, 6 -9 aluminum and zinc compounds, 10 -16 and other miscellaneous reagents like BuSnCl 3 , 17 tin-substituted silica molecular sieve, 18 and Grignard reagent. 19 Recently, trivalent lanthanide alkoxides also were reported to initiate effectively the polymerization of lactide.…”

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

“…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.…”