By means of the intensity theory of X-ray scattering and the two-phase concept of high polymer, the basic formula of the crystaUinity in block copolymers has been proposed after the corrections of atomic, temperature,...By means of the intensity theory of X-ray scattering and the two-phase concept of high polymer, the basic formula of the crystaUinity in block copolymers has been proposed after the corrections of atomic, temperature, absorption, Lorentz and polarization factor. Application of this method to different type poly (oxyethylene-styrene)block copolymers and the same type block copolymers with different EO contents indicates that the crystallinity in poly (oxyethylene-styrene ) block copolymers increases with the increase of the EO content and decreases in the order: PEO-PS-PEO>PEO-PS>PS-PEO-PS.展开更多
A novel kind of polymeric solid electrolyte,PVAEO_16,which possesses both ion conduction and electrochromic characteristics,was synthesized.Its anion conductivity was 1.9× 10^(-6)S·cm^(-1)(25℃).PVAEO_(16)—...A novel kind of polymeric solid electrolyte,PVAEO_16,which possesses both ion conduction and electrochromic characteristics,was synthesized.Its anion conductivity was 1.9× 10^(-6)S·cm^(-1)(25℃).PVAEO_(16)—based ECD could display reversibly the color of yellow and bluish violet over 1.7 V.The color—changing response time was 0.6 s and 1.3 s(±2.0V),re- spectively.The storage time of bluish violet under open circuit was more than 16 hours.展开更多
Polyurethane elastomers derived from 4,4 ' -methylene bis(phenyl isocyanate), butylene glycol and the low oxyethylene moiety content copolyether of tetrahydrofuran and ethylene oxide, obtained by copolymerization ...Polyurethane elastomers derived from 4,4 ' -methylene bis(phenyl isocyanate), butylene glycol and the low oxyethylene moiety content copolyether of tetrahydrofuran and ethylene oxide, obtained by copolymerization using heteropolyacid-ethylene oxide initiator system, were prepared. The polyurethanes exhibited an increased water absorption and much better low temperature resilience, which remained high even at a temperature of -3 degreesC, while that of polyurethane based upon poly(tetramethylene ether) glycol of the 'same molecular weight, i.e. being 2000, and molecular weight distribution, i.e, in the range of 1.4-1.5, starts to decrease dramatically at 5 degreesC.展开更多
文摘By means of the intensity theory of X-ray scattering and the two-phase concept of high polymer, the basic formula of the crystaUinity in block copolymers has been proposed after the corrections of atomic, temperature, absorption, Lorentz and polarization factor. Application of this method to different type poly (oxyethylene-styrene)block copolymers and the same type block copolymers with different EO contents indicates that the crystallinity in poly (oxyethylene-styrene ) block copolymers increases with the increase of the EO content and decreases in the order: PEO-PS-PEO>PEO-PS>PS-PEO-PS.
基金The project is supported by National Natural Seience Foundation of China.
文摘A novel kind of polymeric solid electrolyte,PVAEO_16,which possesses both ion conduction and electrochromic characteristics,was synthesized.Its anion conductivity was 1.9× 10^(-6)S·cm^(-1)(25℃).PVAEO_(16)—based ECD could display reversibly the color of yellow and bluish violet over 1.7 V.The color—changing response time was 0.6 s and 1.3 s(±2.0V),re- spectively.The storage time of bluish violet under open circuit was more than 16 hours.
基金This work was financially supported by the Doctoral Program Foundation of Institution of High Education.
文摘Polyurethane elastomers derived from 4,4 ' -methylene bis(phenyl isocyanate), butylene glycol and the low oxyethylene moiety content copolyether of tetrahydrofuran and ethylene oxide, obtained by copolymerization using heteropolyacid-ethylene oxide initiator system, were prepared. The polyurethanes exhibited an increased water absorption and much better low temperature resilience, which remained high even at a temperature of -3 degreesC, while that of polyurethane based upon poly(tetramethylene ether) glycol of the 'same molecular weight, i.e. being 2000, and molecular weight distribution, i.e, in the range of 1.4-1.5, starts to decrease dramatically at 5 degreesC.
