以碘代等规聚丙烯为大分子反应中间体,通过季胺化亲核取代反应和点击化学反应,制备了N-甲基咪唑聚丙烯离聚体(IA)和邻巯基苯胺盐酸盐聚丙烯离聚体(IB),并将其作为等规聚丙烯/生物基尼龙11 (i PP/PA11)共混体系的增容剂.通过动态力学分析...以碘代等规聚丙烯为大分子反应中间体,通过季胺化亲核取代反应和点击化学反应,制备了N-甲基咪唑聚丙烯离聚体(IA)和邻巯基苯胺盐酸盐聚丙烯离聚体(IB),并将其作为等规聚丙烯/生物基尼龙11 (i PP/PA11)共混体系的增容剂.通过动态力学分析(DMA)、扫描电镜(SEM)和力学性能测试,对i PP/PA11/聚丙烯离聚体三元共混体系的相形态与性能进行了系统研究. DMA测试结果显示,2种聚丙烯离聚体使i PP/PA11共混体系的玻璃化转变温度Tg相互靠近;SEM结果显示,离聚体的加入使分散相粒子尺寸显著减小,两相界面作用力增加;力学性能测试表明,iPP/PA11/IA、i PP/PA11/IB三元共混体系的拉伸强度和冲击强度保持较好的水平.以上研究结果表明,IA和IB均可以显著改善i PP/PA11共混体系的相容性.展开更多
Polyamide 11 (PA 11) is a widely used polyamide resin, but its application is limited since the impact properties, tensile strength, and thermal properties are not very satisfactory for industrial application. In orde...Polyamide 11 (PA 11) is a widely used polyamide resin, but its application is limited since the impact properties, tensile strength, and thermal properties are not very satisfactory for industrial application. In order to improve the mechanical properties of PA 11, in this paper, the preparation of polyamide 11/clay nanocomposites (PACN) via in-situ intercalated polymerization was reported. SEM, TEM and XRD were employed to investigate the dispersion of clay sheet in the matrix. The results indicate that clay layers were homogeneously dispersed in PA11 matrix on a nano-scale, and an exfoliated and intercalated structure co-existed in the composites. The mechanical and thermal properties of the obtained nanocomposites were improved to certain extent by the addition of clay.展开更多
Polyamide I1 （PAll） and its nanocomposites with different organoclay loadings were prepared by melt-compounding and subsequent pelletizing. The crystal phase transitions of PAl 1 and its clay nanocomposites were inv...Polyamide I1 （PAll） and its nanocomposites with different organoclay loadings were prepared by melt-compounding and subsequent pelletizing. The crystal phase transitions of PAl 1 and its clay nanocomposites were investigated by variable-temperature X-ray diffraction. It was found that the Brill transition of the nanocomposite was 20 K higher than that of the neat PAl 1 for both heating and cooling processes. The PAl 1 d-spacings of the nanocomposites were observed to be smaller than those of the neat PAl 1 for melt crystallization. The constraints imposed by the addition of layered clay, restricting the thermal expansion of the polymer chains, are probably responsible for such a reduction of the d-spacing.展开更多
The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional ep...The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional epoxy compatibilizer(Joncryl ADR-4368).The morphological,thermal,rheological,and mechanical properties of PEF/PA11 blends were investigated.Compared with neat PEF,the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two polymers.When Joncryl was incorporated into PEF/PA11 blends,the interfacial tension between PEF and PA11 was obviously reduced,reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy(SEM).The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend,which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular chains.Thus,the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of Joncryl.The compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1%and 30.3kJ/m2,respectively,compared with those of 3.6%and 3.8 kJ/m2 for neat PEF,respectively.This work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.展开更多
以聚酰胺11(PA11)和热塑性聚氨酯弹性体(TPU)为原料,4,4'-二苯甲烷二异氰酸酯(MDI)为增容剂,采用熔融共混法制备PA11/TPU复合材料。研究不同含量的MDI对复合材料的力学性能、微观形态及非等温结晶性能的影响。结果表明:随着MDI含量...以聚酰胺11(PA11)和热塑性聚氨酯弹性体(TPU)为原料,4,4'-二苯甲烷二异氰酸酯(MDI)为增容剂,采用熔融共混法制备PA11/TPU复合材料。研究不同含量的MDI对复合材料的力学性能、微观形态及非等温结晶性能的影响。结果表明:随着MDI含量的增加,复合材料的拉伸强度增大,冲击强度先增大后减小。当MDI含量为0.8%时,复合材料的力学性能达到最佳,拉伸强度为66.3 MPa,断裂伸长率为123%,冲击强度达到10 k J/m2,较不加MDI的复合材料增加了45%,此时PA11和TPU的相容性较好,分子间交联程度适中。非等温结晶分析表明:Mo法适用于处理PA11/TPU复合材料的非等温结晶过程;在非等温结晶过程中,MDI的加入对复合材料的非等温结晶行为产生影响,MDI的加入抑制了分子链的运动,使结晶速率下降。展开更多
基金We would like to express our heartfelt thanks to the China National Distinguished Young Investigator Fund(No. 29925413) and the National Natural Science Foundation of China (No. 20274028) for Financial Support.
文摘Polyamide 11 (PA 11) is a widely used polyamide resin, but its application is limited since the impact properties, tensile strength, and thermal properties are not very satisfactory for industrial application. In order to improve the mechanical properties of PA 11, in this paper, the preparation of polyamide 11/clay nanocomposites (PACN) via in-situ intercalated polymerization was reported. SEM, TEM and XRD were employed to investigate the dispersion of clay sheet in the matrix. The results indicate that clay layers were homogeneously dispersed in PA11 matrix on a nano-scale, and an exfoliated and intercalated structure co-existed in the composites. The mechanical and thermal properties of the obtained nanocomposites were improved to certain extent by the addition of clay.
基金financially supported by the National Natural Science Foundation of China(No.51125011)Guangxi Small Highland Innovation Team of Talents in Colleges and UniversitiesGuangxi Funds for Specially-appointed Expert
文摘Polyamide I1 （PAll） and its nanocomposites with different organoclay loadings were prepared by melt-compounding and subsequent pelletizing. The crystal phase transitions of PAl 1 and its clay nanocomposites were investigated by variable-temperature X-ray diffraction. It was found that the Brill transition of the nanocomposite was 20 K higher than that of the neat PAl 1 for both heating and cooling processes. The PAl 1 d-spacings of the nanocomposites were observed to be smaller than those of the neat PAl 1 for melt crystallization. The constraints imposed by the addition of layered clay, restricting the thermal expansion of the polymer chains, are probably responsible for such a reduction of the d-spacing.
基金This work was financially supported by the National Natural Science Foundation of China(No.51803224).
文摘The objective of this study was to improve the toughness of bio based brittle poly(ethylene 2,5-furandicarboxylate)(PEF)by melt blending with bio based polyamide11(PA11)in the presence of a reactive multifunctional epoxy compatibilizer(Joncryl ADR-4368).The morphological,thermal,rheological,and mechanical properties of PEF/PA11 blends were investigated.Compared with neat PEF,the toughness of PEF/PA11 blend was not improved in the absence of the reactive compatibilizer due to the poor compatibility between the two polymers.When Joncryl was incorporated into PEF/PA11 blends,the interfacial tension between PEF and PA11 was obviously reduced,reflecting in the fine average particle size and narrow distribution of PA11 dispersed phase as observed by scanning electron microscopy(SEM).The complex viscosities of PEF/PA11 blends with Joncryl were much higher than that of PEF/PA11 blend,which could be ascribed to the formation of graft copolymers through the epoxy groups of Joncryl reacting with the end groups of PEF and PA11 molecular chains.Thus,the compatibility and interfacial adhesion between PEF and PA11 were greatly improved in the presence of Joncryl.The compatibilized PEF/PA11 blend with 1.5 phr Joncryl exhibited significantly improved elongation at break and unnotch impact strength with values of 90.1%and 30.3kJ/m2,respectively,compared with those of 3.6%and 3.8 kJ/m2 for neat PEF,respectively.This work provides an effective approach to improve the toughness of PEF which may expand its widespread application in packaging.
文摘以聚酰胺11(PA11)和热塑性聚氨酯弹性体(TPU)为原料,4,4'-二苯甲烷二异氰酸酯(MDI)为增容剂,采用熔融共混法制备PA11/TPU复合材料。研究不同含量的MDI对复合材料的力学性能、微观形态及非等温结晶性能的影响。结果表明:随着MDI含量的增加,复合材料的拉伸强度增大,冲击强度先增大后减小。当MDI含量为0.8%时,复合材料的力学性能达到最佳,拉伸强度为66.3 MPa,断裂伸长率为123%,冲击强度达到10 k J/m2,较不加MDI的复合材料增加了45%,此时PA11和TPU的相容性较好,分子间交联程度适中。非等温结晶分析表明:Mo法适用于处理PA11/TPU复合材料的非等温结晶过程;在非等温结晶过程中,MDI的加入对复合材料的非等温结晶行为产生影响,MDI的加入抑制了分子链的运动,使结晶速率下降。
