Aliphatic hyperbranched poly(ester amine)s with terminal acrylate groups were synthesized by Michael addition reaction between pizine and trimethylol propanetriacrylate (TMPTA) under various molar ratios, and their st...Aliphatic hyperbranched poly(ester amine)s with terminal acrylate groups were synthesized by Michael addition reaction between pizine and trimethylol propanetriacrylate (TMPTA) under various molar ratios, and their structures were characterized by 1H NMR,GPC and DSC analysis.The multi peaks within δ 4.04~4.18 (RCH 2OCOR′) in the 1H NMR spectra were analyzed and the peaks at δ 4.15, δ 4 06~4 07 and δ 4.04 can be assigned to terminal ( T ),linear ( L ) and dendritic units ( D ),respectively.Based on 1H NMR spectra,the degree of branching ( DB) for these polymers were calculated by using both the Fréchet method and the Frey method.With the molar ratio between pizine and TMPTA increased to 1/1,the terminate units decreased,both of the dendritic and linear units increased,while M n and M w/ M n became large and the T g value became high,accordingly.Moreover,cured films were obtained through UV radiation of the polymers.The gel contents for the films decreased with increasing the molar ratio between pizine and TMPTA,which may account for the changes of their mechanical properties.展开更多
The diblock copolymers of methyl acrylate and perfluoroalkyl ethyl acrylate(FAEA) were synthesized by atom transfer radical polymerization (ATRP).GPC, 1H-NMR and fluorine-elementary analysis (F-EA) were used to study ...The diblock copolymers of methyl acrylate and perfluoroalkyl ethyl acrylate(FAEA) were synthesized by atom transfer radical polymerization (ATRP).GPC, 1H-NMR and fluorine-elementary analysis (F-EA) were used to study the structure of the block copolymers.To combine GPC with NMR and to combine GPC with F-EA were used to calculate the block length.It was found interestingly that the results of 1H-NMR showed a “temperature-dependent" feature.It means the relative ratios of MA block to FAEA block calculated from NMR were changed with measuring temperature.It might be caused by the formation of molecular association.Temperature and solvents can affect the degree of association.Therefore, 1H-NMR and GPC can’t be used in quantitative analysis of the fluorinated diblock copolymer.To combine GPC with F-EA is suitable for the characterization of fluorinated diblock copolymers.展开更多
文摘Aliphatic hyperbranched poly(ester amine)s with terminal acrylate groups were synthesized by Michael addition reaction between pizine and trimethylol propanetriacrylate (TMPTA) under various molar ratios, and their structures were characterized by 1H NMR,GPC and DSC analysis.The multi peaks within δ 4.04~4.18 (RCH 2OCOR′) in the 1H NMR spectra were analyzed and the peaks at δ 4.15, δ 4 06~4 07 and δ 4.04 can be assigned to terminal ( T ),linear ( L ) and dendritic units ( D ),respectively.Based on 1H NMR spectra,the degree of branching ( DB) for these polymers were calculated by using both the Fréchet method and the Frey method.With the molar ratio between pizine and TMPTA increased to 1/1,the terminate units decreased,both of the dendritic and linear units increased,while M n and M w/ M n became large and the T g value became high,accordingly.Moreover,cured films were obtained through UV radiation of the polymers.The gel contents for the films decreased with increasing the molar ratio between pizine and TMPTA,which may account for the changes of their mechanical properties.
文摘The diblock copolymers of methyl acrylate and perfluoroalkyl ethyl acrylate(FAEA) were synthesized by atom transfer radical polymerization (ATRP).GPC, 1H-NMR and fluorine-elementary analysis (F-EA) were used to study the structure of the block copolymers.To combine GPC with NMR and to combine GPC with F-EA were used to calculate the block length.It was found interestingly that the results of 1H-NMR showed a “temperature-dependent" feature.It means the relative ratios of MA block to FAEA block calculated from NMR were changed with measuring temperature.It might be caused by the formation of molecular association.Temperature and solvents can affect the degree of association.Therefore, 1H-NMR and GPC can’t be used in quantitative analysis of the fluorinated diblock copolymer.To combine GPC with F-EA is suitable for the characterization of fluorinated diblock copolymers.