A novel well-defined water-soluble macromonomer based on 2-(dimethylamino) ethyl methacry-late(DMAEMA) was synthesized by using functional initiators such as potassium alcoholate of trimethylol-propane allyl ether via...A novel well-defined water-soluble macromonomer based on 2-(dimethylamino) ethyl methacry-late(DMAEMA) was synthesized by using functional initiators such as potassium alcoholate of trimethylol-propane allyl ether via oxyanion-initiated polymerization. GPC and 1H NMR studies confirmed that themacromonomers had narrow molecular weight distribution and each Poly(DMAEMA) chain contained apolymerizable allyl group. The macromonomers were highly surface active in aqueous media. They havepotential applications in preparation of surface-clean and functional latexes both as effective stabilizers andas co-monomers.展开更多
Vibrational spectroscopy(ATR-FTIR and Raman) was used to investigate the interaction and conformation transition in the blend films of silk fibroin(SF) and silk-protein like polymers(P1, P2) containing the oligopeptid...Vibrational spectroscopy(ATR-FTIR and Raman) was used to investigate the interaction and conformation transition in the blend films of silk fibroin(SF) and silk-protein like polymers(P1, P2) containing the oligopeptide segments[(Ala) 4, GlyAlaGlyAla] which derived from the crystal region of spider dragline silk and silkworm(Bombyx mori) silk. The results revealed that the intermolecular hydrogen-bond interaction, which was formed between the molecular chains of SF and the oligopeptide segments in P1 and P2, induced a partial random coil/α-helix conformation transfer to β-sheet conformation after blending. And β-sheet and random coil/α-helix conformation coexisted in the SF/P1 and SF/P2 blend films, while the predominant conformations in the pure SF and P1 films were random coil/α-helix. These conclusions would be significant for artificial spinning of the regenerated silk fibroin.展开更多
A partial conjugated hyperbranched light-emitting polymer was obtained by copolymerization of a fluorescent A2 monomer and a non-conjugated B4 monomer.The polymer displays a good thermal stability compared with its li...A partial conjugated hyperbranched light-emitting polymer was obtained by copolymerization of a fluorescent A2 monomer and a non-conjugated B4 monomer.The polymer displays a good thermal stability compared with its linear counterparts,and a good solubility,controllable luminescent properties compared with full-conjugated light-emitting polymers.展开更多
Pattern formation in polymeric hydrogel associated with volume phase transition was observed in strong gel shrinking. Chemically cross linked poly(sodium acrylate/acrylamide) gel was prepared and shaped by capillary. ...Pattern formation in polymeric hydrogel associated with volume phase transition was observed in strong gel shrinking. Chemically cross linked poly(sodium acrylate/acrylamide) gel was prepared and shaped by capillary. The gel cylinder was suddenly dipped into acetone or into an acid aqueous solution. The former exhibited bamboo like pattern, similar to the report in the literature. But a novel pattern, gel helix or gel spring, was found in the latter case. Macroscopic patterns only occurred in a strong gel collapse, and nothing was found in a step by step volume shrinking. The helix is with period between 0 1 to 1 mm and formed within 100 second. Both right hand sense and left hand sense could be obtained. Once formed, the gel helix cannot be recovered by re swelling in basic solution. Surface crack and its helical growth were observed and could account for the formation of gel helix preliminarily.展开更多
文摘A novel well-defined water-soluble macromonomer based on 2-(dimethylamino) ethyl methacry-late(DMAEMA) was synthesized by using functional initiators such as potassium alcoholate of trimethylol-propane allyl ether via oxyanion-initiated polymerization. GPC and 1H NMR studies confirmed that themacromonomers had narrow molecular weight distribution and each Poly(DMAEMA) chain contained apolymerizable allyl group. The macromonomers were highly surface active in aqueous media. They havepotential applications in preparation of surface-clean and functional latexes both as effective stabilizers andas co-monomers.
文摘Vibrational spectroscopy(ATR-FTIR and Raman) was used to investigate the interaction and conformation transition in the blend films of silk fibroin(SF) and silk-protein like polymers(P1, P2) containing the oligopeptide segments[(Ala) 4, GlyAlaGlyAla] which derived from the crystal region of spider dragline silk and silkworm(Bombyx mori) silk. The results revealed that the intermolecular hydrogen-bond interaction, which was formed between the molecular chains of SF and the oligopeptide segments in P1 and P2, induced a partial random coil/α-helix conformation transfer to β-sheet conformation after blending. And β-sheet and random coil/α-helix conformation coexisted in the SF/P1 and SF/P2 blend films, while the predominant conformations in the pure SF and P1 films were random coil/α-helix. These conclusions would be significant for artificial spinning of the regenerated silk fibroin.
文摘A partial conjugated hyperbranched light-emitting polymer was obtained by copolymerization of a fluorescent A2 monomer and a non-conjugated B4 monomer.The polymer displays a good thermal stability compared with its linear counterparts,and a good solubility,controllable luminescent properties compared with full-conjugated light-emitting polymers.
文摘Pattern formation in polymeric hydrogel associated with volume phase transition was observed in strong gel shrinking. Chemically cross linked poly(sodium acrylate/acrylamide) gel was prepared and shaped by capillary. The gel cylinder was suddenly dipped into acetone or into an acid aqueous solution. The former exhibited bamboo like pattern, similar to the report in the literature. But a novel pattern, gel helix or gel spring, was found in the latter case. Macroscopic patterns only occurred in a strong gel collapse, and nothing was found in a step by step volume shrinking. The helix is with period between 0 1 to 1 mm and formed within 100 second. Both right hand sense and left hand sense could be obtained. Once formed, the gel helix cannot be recovered by re swelling in basic solution. Surface crack and its helical growth were observed and could account for the formation of gel helix preliminarily.
