Nylon 10T and nylon 10T/1010 samples were synthesized by direct melt polymerization.The isothermal crystallization kinetics of nylon 10T and nylon 10T/1010 was investigated by means of differential scanning calorimetr...Nylon 10T and nylon 10T/1010 samples were synthesized by direct melt polymerization.The isothermal crystallization kinetics of nylon 10T and nylon 10T/1010 was investigated by means of differential scanning calorimetry（DSC）.The crystallization kinetics under isothermal condition has been analyzed by the Avrami equation.It was found that the Avrami equation was well-suited to describe the isothermal crystallization kinetics,combined with the results of the Turnbull-Fisher equation.The values of Tm^0 and Kg were obtained by Hoffman-Weeks and Lauritzen-Hoffman equations,respectively.The activation energies for isothermal crystallization of nylon 10T and nylon 10T/1010 were determined using the Arrhenius equation and found to be-123.24 and-81.86 kJ·mol^（-1）,respectively,which reveals that the crystallization ability of nylon 10T/1010was lower than that of nylon 10T during the isothermal crystallization process.The crystal morphology was observed by means of polarized optical microscopy（POM）and X-ray diffraction（XRD）.It was found that the addition of sebacic acid comonomer did not change the crystal form of nylon 10T,but significantly increased the number and decreased the size of spherulites.展开更多
The interface behavior of polyamide 1010 (PA1010) and polypropylene (PP) was studied. In order to improve their interfacial adhesion, functional PP was prepared by means of grafting glycidyl methacrylate (GMA) on PP m...The interface behavior of polyamide 1010 (PA1010) and polypropylene (PP) was studied. In order to improve their interfacial adhesion, functional PP was prepared by means of grafting glycidyl methacrylate (GMA) on PP main chains and used instead of plain PP. Several technological characterizations were performed here on their interfaces. ESCA was used to confirm that some kind of reaction occurred between end groups of PA1010 and epoxy species of PP-g-GMA. The peel test was adopted to measure interfacial adhesion. It was found that the fracture energy of interfaces between PA1010 and PP-g-GMA was dramatically increased with the content of GMA. Their interfaces were observed as being blurred by using SEM and TEM and a crack that could be seen in the case of the interfaces of the PA1010 and the plain PP disappeared.展开更多
Polyamide 1010 is a γ-radiation crosslinkable polymer. After irradiation, it is possible to raise its service temperature up to 240℃ . Network formation greatly changes the crystallization behaviour of the polymer. ...Polyamide 1010 is a γ-radiation crosslinkable polymer. After irradiation, it is possible to raise its service temperature up to 240℃ . Network formation greatly changes the crystallization behaviour of the polymer. In the present work, DSC was used to examine its isothermal crystallization kinetics. It is found that in addition to the necessity of more undercooling and the lowering of crystallization rate, the primary crystallization stage of the irradiated polymer is shortened. This effect is more evident with increasing radiation dose and content of enhanced difunctionai erosslinking agent. However, the crystallization mechanism of the primary stage is not changed as evidenced by the constancy of Avrami exponent. The lamella end surface free energy σ_e calculated according to Hoffman's equation is very sensitive to γ-radiation. It increases abruptly in 2—3 fold even though the radiation dose is not high enough. The origin of this phenomenon may be accounted for in terms of network structure of the polymer.展开更多
基金Supported by the National Science and Technology Support Program of China(No.2013BAE02B01)the Special Project on the Integration of Industry,Education and Research of Guangdong Province(No.2013B090500003)the Commissioner Workstation Project of Guangdong Province(No.2014A090906002)
文摘Nylon 10T and nylon 10T/1010 samples were synthesized by direct melt polymerization.The isothermal crystallization kinetics of nylon 10T and nylon 10T/1010 was investigated by means of differential scanning calorimetry（DSC）.The crystallization kinetics under isothermal condition has been analyzed by the Avrami equation.It was found that the Avrami equation was well-suited to describe the isothermal crystallization kinetics,combined with the results of the Turnbull-Fisher equation.The values of Tm^0 and Kg were obtained by Hoffman-Weeks and Lauritzen-Hoffman equations,respectively.The activation energies for isothermal crystallization of nylon 10T and nylon 10T/1010 were determined using the Arrhenius equation and found to be-123.24 and-81.86 kJ·mol^（-1）,respectively,which reveals that the crystallization ability of nylon 10T/1010was lower than that of nylon 10T during the isothermal crystallization process.The crystal morphology was observed by means of polarized optical microscopy（POM）and X-ray diffraction（XRD）.It was found that the addition of sebacic acid comonomer did not change the crystal form of nylon 10T,but significantly increased the number and decreased the size of spherulites.
基金This work was supported by the National Natural Science Foundation of China.
文摘The interface behavior of polyamide 1010 (PA1010) and polypropylene (PP) was studied. In order to improve their interfacial adhesion, functional PP was prepared by means of grafting glycidyl methacrylate (GMA) on PP main chains and used instead of plain PP. Several technological characterizations were performed here on their interfaces. ESCA was used to confirm that some kind of reaction occurred between end groups of PA1010 and epoxy species of PP-g-GMA. The peel test was adopted to measure interfacial adhesion. It was found that the fracture energy of interfaces between PA1010 and PP-g-GMA was dramatically increased with the content of GMA. Their interfaces were observed as being blurred by using SEM and TEM and a crack that could be seen in the case of the interfaces of the PA1010 and the plain PP disappeared.
文摘Polyamide 1010 is a γ-radiation crosslinkable polymer. After irradiation, it is possible to raise its service temperature up to 240℃ . Network formation greatly changes the crystallization behaviour of the polymer. In the present work, DSC was used to examine its isothermal crystallization kinetics. It is found that in addition to the necessity of more undercooling and the lowering of crystallization rate, the primary crystallization stage of the irradiated polymer is shortened. This effect is more evident with increasing radiation dose and content of enhanced difunctionai erosslinking agent. However, the crystallization mechanism of the primary stage is not changed as evidenced by the constancy of Avrami exponent. The lamella end surface free energy σ_e calculated according to Hoffman's equation is very sensitive to γ-radiation. It increases abruptly in 2—3 fold even though the radiation dose is not high enough. The origin of this phenomenon may be accounted for in terms of network structure of the polymer.
