The molecular motion in polyepichlorohydrin (PEPCH), in solution and bulk, was studied by high resolution NMR by means of line width, spin-lattice relaxation time T_1 and nuclear Overhauser effect NOE. The results sho...The molecular motion in polyepichlorohydrin (PEPCH), in solution and bulk, was studied by high resolution NMR by means of line width, spin-lattice relaxation time T_1 and nuclear Overhauser effect NOE. The results show that the VJGM model can describe the main chain motion of PEPCH in solution perfectly. In bulk state, the relationship between the line width and the temperature is consistent with WLF equation, but that between the high frequency molecular motion correlation time (in T_1 scale ) and temperature is consistent with Arrhenius equation. The motion parameters of PEPCH in both states were calculated. The internal rotation motion of side—CH_2Cl group was analyzed by using equal three-site jump and diffusion internal rotation model in both states.展开更多
Three novel copolymers,poly[1-(4-(benzothiazole-2-thio-alkyloxy)-biphenyl-4'-oxy)2.3-epoxypropane]s,were synthesized by the reaction of polyepichlorohydrin with obtained monomers,4-(benzothiazole-2-thio-alkyloxy...Three novel copolymers,poly[1-(4-(benzothiazole-2-thio-alkyloxy)-biphenyl-4'-oxy)2.3-epoxypropane]s,were synthesized by the reaction of polyepichlorohydrin with obtained monomers,4-(benzothiazole-2-thio-alkyloxy)biphenyl-4'-ols,in which the number of methylene unit in substitution group of biphenyl group was 2,4,6,respectively.The structures of obtained compounds were confirmed by elemental analysis and 1H NMR.The decomposition temperatures of copolymers were near 340 ℃.Differential scanning calorimetry(DSC) measurement and polarized optical microscopy(POM) observation showed the resulting copolymers did not exhibit thermotropic liquid crystalline mesomophism and belonged to semi-crystalline substance.展开更多
基金The project was supported by the National Natural Science Foundation of China
文摘The molecular motion in polyepichlorohydrin (PEPCH), in solution and bulk, was studied by high resolution NMR by means of line width, spin-lattice relaxation time T_1 and nuclear Overhauser effect NOE. The results show that the VJGM model can describe the main chain motion of PEPCH in solution perfectly. In bulk state, the relationship between the line width and the temperature is consistent with WLF equation, but that between the high frequency molecular motion correlation time (in T_1 scale ) and temperature is consistent with Arrhenius equation. The motion parameters of PEPCH in both states were calculated. The internal rotation motion of side—CH_2Cl group was analyzed by using equal three-site jump and diffusion internal rotation model in both states.
基金Funded by the National Natural Science Foundation of China (No.200474049)Specialized Research Fund for the Doctoral Program of Higher Education of China (No.20040497001)
文摘Three novel copolymers,poly[1-(4-(benzothiazole-2-thio-alkyloxy)-biphenyl-4'-oxy)2.3-epoxypropane]s,were synthesized by the reaction of polyepichlorohydrin with obtained monomers,4-(benzothiazole-2-thio-alkyloxy)biphenyl-4'-ols,in which the number of methylene unit in substitution group of biphenyl group was 2,4,6,respectively.The structures of obtained compounds were confirmed by elemental analysis and 1H NMR.The decomposition temperatures of copolymers were near 340 ℃.Differential scanning calorimetry(DSC) measurement and polarized optical microscopy(POM) observation showed the resulting copolymers did not exhibit thermotropic liquid crystalline mesomophism and belonged to semi-crystalline substance.