利用双螺杆挤出机熔融共混的方法制备了不同含量的碳纤维(CF)与尼龙共聚物(PA6T/66)复合材料,通过差示扫描量热仪、热重分析仪、扫描电子显微镜和力学性能测试研究了该复合材料的热性能、力学性能和断面形态结构。结果显示,复合材料的...利用双螺杆挤出机熔融共混的方法制备了不同含量的碳纤维(CF)与尼龙共聚物(PA6T/66)复合材料,通过差示扫描量热仪、热重分析仪、扫描电子显微镜和力学性能测试研究了该复合材料的热性能、力学性能和断面形态结构。结果显示,复合材料的起始分解温度均在400℃以上,熔点都在300℃左右。随着CF含量的增加,复合材料的拉伸强度、弯曲强度和冲击强度都相应增加,当CF质量分数达到40%时,复合材料的拉伸强度、弯曲强度和冲击强度分别达到最大值:226.1 MPa、354.7 MPa、54.1 k J/m2。展开更多
The effects of polytetrafluoroethylene (PTFE) content on water-absorptivity, tensile strength, flexural strength, and notched impact strength of polytetrafluoroethylene/polyamide 6 (PTFE/PA6) and polytetrafluoroethyle...The effects of polytetrafluoroethylene (PTFE) content on water-absorptivity, tensile strength, flexural strength, and notched impact strength of polytetrafluoroethylene/polyamide 6 (PTFE/PA6) and polytetrafluoroethylene/polyamide 66 (PTFE/PA66) blends were investigated by water immersion test, uniaxial tensile test, three-point test, and Charpy impact fracture test. The water-absorptivity in the blend decreases with increasing PTFE content, which indicates that the PTFE phase restrains the polyamide phase from water absorption. For water-free blends, the addition of PTFE causes a reduction in tensile strength, while for water-absorbed PTFE/PA6 blends, the tensile strength increases with increasing PTFE. Simultaneously, the absorbed water improves the elongation, but results in a notable reduction in flexural strength of the blends. Although the addition of PTFE causes a reduction in notched impact strength of the blends, as compared to pure polyamide, the absorbed water has little effects on the notched impact strength of the blends. Finally, the effects of temperature and loading frequency on complex viscosity parameters of PTFE/PA6 and PTFE/PA66 melts were tested. It is found that the complex viscosity of PTFE/PA6 melt is reversed with increasing temperature and shear velocity, but that of PTFE/PA66 melt increases approximately in exponential form with increasing temperature. To fill polyamide with suitable mass percentage of PTFE can effectively reduce the viscosity of blend, and as a result, the molding and processing properties are improved.展开更多
文摘利用双螺杆挤出机熔融共混的方法制备了不同含量的碳纤维(CF)与尼龙共聚物(PA6T/66)复合材料,通过差示扫描量热仪、热重分析仪、扫描电子显微镜和力学性能测试研究了该复合材料的热性能、力学性能和断面形态结构。结果显示,复合材料的起始分解温度均在400℃以上,熔点都在300℃左右。随着CF含量的增加,复合材料的拉伸强度、弯曲强度和冲击强度都相应增加,当CF质量分数达到40%时,复合材料的拉伸强度、弯曲强度和冲击强度分别达到最大值:226.1 MPa、354.7 MPa、54.1 k J/m2。
基金Prqject(10572123) supported by the National Natural Science Foundation of China Project(05JJ30014) supported by the Natural Science Foundation of Hunan Province, China Project(05C100) supported by the Scientific Research Fund of Education Department of Hunan Province, China
文摘The effects of polytetrafluoroethylene (PTFE) content on water-absorptivity, tensile strength, flexural strength, and notched impact strength of polytetrafluoroethylene/polyamide 6 (PTFE/PA6) and polytetrafluoroethylene/polyamide 66 (PTFE/PA66) blends were investigated by water immersion test, uniaxial tensile test, three-point test, and Charpy impact fracture test. The water-absorptivity in the blend decreases with increasing PTFE content, which indicates that the PTFE phase restrains the polyamide phase from water absorption. For water-free blends, the addition of PTFE causes a reduction in tensile strength, while for water-absorbed PTFE/PA6 blends, the tensile strength increases with increasing PTFE. Simultaneously, the absorbed water improves the elongation, but results in a notable reduction in flexural strength of the blends. Although the addition of PTFE causes a reduction in notched impact strength of the blends, as compared to pure polyamide, the absorbed water has little effects on the notched impact strength of the blends. Finally, the effects of temperature and loading frequency on complex viscosity parameters of PTFE/PA6 and PTFE/PA66 melts were tested. It is found that the complex viscosity of PTFE/PA6 melt is reversed with increasing temperature and shear velocity, but that of PTFE/PA66 melt increases approximately in exponential form with increasing temperature. To fill polyamide with suitable mass percentage of PTFE can effectively reduce the viscosity of blend, and as a result, the molding and processing properties are improved.