Synthesis of grafted polysilsesquioxane by ring-opening polymerization of lactide and trimethylene carbonate

Abstract

The polysilsesquioxane (PSQ) containing 3-aminopropyl and phenyl groups (APSQ) was prepared from the corresponding trimethoxysilanes by co-condensation under basic conditions. The amino groups on APSQ were used as the initiator species for the graft polymerization of 1,3-trimethylene carbonate (TMC) and L-(-)-lactide (LA). The ring-opening polymerization of TMC and LA in the presence of the catalytic 1-trimethylsilylimidazole proceeded effectively to afford the PSQ with poly(TMC) and/or poly(LA) as the graft chains. The grafted PSQ containing poly(LA) showed the heat durability as an advantage of the hybrid polymer. In differential scanning calorimetry analysis, the grafted random copolymer of TMC and LA showed no clear endotherm corresponding to melting point (T m ). For the poly(LA)-grafted PSQ, the peak indicating T m was observed in the first heating run, but the corresponding peak was very small in the second run.

Thermosensitive Biodegradable Homopolymer of Trimethylene Carbonate Derivative at Body Temperature

“…For example, the alternating copolymerization of limonene oxide and carbon dioxide has been achieved with a specific single site catalyst . PTMC is also known as a biodegradable synthetic polymer and has been actually used as a biomedical material in suture thread, taking advantage of its soft characteristics. − Recently, research on novel PTMC derivatives and copolymers for biomaterial use has attracted attention, due to the organic catalyst system reported by Waymouth, Hedrick, and co-workers in 2007. , Furthermore, micelle and polymersome , preparations have predominantly been investigated as drug delivery systems by using copolymers with PTMC and hydrophilic polymers or by using trimethylene carbonate (TMC) derivatives with a protected carboxylic acid group at the side chain, such as 5-methyl-5-benzyloxycarbonyl-1,3-dioxan-2-one − and 3-chloropropyl 5-methyl-2-oxo-1,3-dioxane-5-carboxylate . Moreover, temperature responsiveness was achieved with PTMC derivatives by introducing a PEG domain into the block copolymer , and into the side chain along the polymer main chain .…”

Graft polymerization of acrylamide monomers from polysilsesquioxane containing xanthate groups

“…With the regard to this expectation, we also tried to develop new multifunctional hybrid materials using acrylamide monomers by the graft polymerizations from polysilsesquioxane (PSQ). [21][22][23][24][25][26] In fact, the graftings of polymeric N,N-dimethylacrylamide (DMAA) and N-isopropylacrylamide (NIPAM) successfully produced amphiphilic and thermoresponsive PSQs. 23,24 For the graft polymerizations, the reversible addition-fragmentation chain transfer (RAFT) process was utilized, in which the N,Ndimethyldithiocarbamate (DTC) group was chosen as the chain transfer species.…”