Degradable graft copolymers of vinyl acetate and sericin were prepared firstly. Their structures, mechanical and biodegradable properties, and thermal stability were examined by IR, TG and the tensile machine.The resu...Degradable graft copolymers of vinyl acetate and sericin were prepared firstly. Their structures, mechanical and biodegradable properties, and thermal stability were examined by IR, TG and the tensile machine.The results indicate that the graft copolymers prepared have higher tensile strength, Youngs modulus, elongation, thermostability and degradation rate than poly(vinyl acetate).展开更多
Amphiphilic graft copolymers having poly（phthalazinone ether sulfone ketone）（PPESK） backbones and poly（ethylene glycol） side chains were synthesized through a modified Williamson ether method.Initially,chloromet...Amphiphilic graft copolymers having poly（phthalazinone ether sulfone ketone）（PPESK） backbones and poly（ethylene glycol） side chains were synthesized through a modified Williamson ether method.Initially,chloromethylated PPESK（CMPPESK） was prepared using chloromethylether as chloromethylation agent.Then,PPESK-g-PEGs were synthesized via the coupling of CMPPESK with alkoxides formed from PEG mono methyl ether（PEG-OH） and sodium hydride.Two PEG-OHs with the average molecular weight of 350 g/mol and 750 g/mol,respectively were used as the grafting reactants.The grafting of PEG-OHs onto PPESK backbones was confirmed by FT-IR,1H-NMR and solid13C CP-MAS NMR.The grafting degrees of PEG-OH were calculated from1H-NMR analysis,and the obtained results were approximately consistent with those from TGA analysis.The resultant PPESK-g-PEG copolymers were hydrophilic,but water insoluble,rendering them potential candidates as surface modifying additive for PPESK porous membranes.展开更多
文摘Degradable graft copolymers of vinyl acetate and sericin were prepared firstly. Their structures, mechanical and biodegradable properties, and thermal stability were examined by IR, TG and the tensile machine.The results indicate that the graft copolymers prepared have higher tensile strength, Youngs modulus, elongation, thermostability and degradation rate than poly(vinyl acetate).
文摘Amphiphilic graft copolymers having poly（phthalazinone ether sulfone ketone）（PPESK） backbones and poly（ethylene glycol） side chains were synthesized through a modified Williamson ether method.Initially,chloromethylated PPESK（CMPPESK） was prepared using chloromethylether as chloromethylation agent.Then,PPESK-g-PEGs were synthesized via the coupling of CMPPESK with alkoxides formed from PEG mono methyl ether（PEG-OH） and sodium hydride.Two PEG-OHs with the average molecular weight of 350 g/mol and 750 g/mol,respectively were used as the grafting reactants.The grafting of PEG-OHs onto PPESK backbones was confirmed by FT-IR,1H-NMR and solid13C CP-MAS NMR.The grafting degrees of PEG-OH were calculated from1H-NMR analysis,and the obtained results were approximately consistent with those from TGA analysis.The resultant PPESK-g-PEG copolymers were hydrophilic,but water insoluble,rendering them potential candidates as surface modifying additive for PPESK porous membranes.
