尼龙11／SiC复合材料等温结晶性能研究*

摘要

利用差示扫描量热法研究尼龙(PA)11/SiC复合材料在不同结晶温度的等温结晶及熔融行为，采用Avrami方程研究复合材料的等温结晶动力学，用Hoffman-Weeks理论研究复合材料的平衡熔点。结果表明，Avrami方程能够较好地描述PA11/SiC复合材料的等温结晶动力学；在复合材料中，SiC起到了异相成核作用,提高了等温结晶速率，随着结晶温度的升高，结晶速率逐渐降低；PA11/SiC复合材料等温结晶后的熔融曲线均为双重熔融峰，当结晶温度足够高时，晶体趋于完美，只存在一个熔融峰；与纯PA11相比，PA11/SiC复合材料有较低的平衡熔点。%Isothermal crystallization and melting behaviors of nylon(PA)11/SiC composites in different crystallization temperature were investigated by differential scanning calorimetry. The isothermal crystallization kinetics of the composites were investigated by Avrami equation. The equilibrium melting point of the composites were studied by Hoffman-Weeks theory. The experimental results show that the Avrami equation can well describe the isothermal crystallization kinetics of PA11/SiC composites. SiC plays a role of heterogeneous nucleation in composites,improved isothermal crystallization rate. With the increase of crystallization temperature,crystallization rates gradually reduce. Isothermal melting curve of PA11/SiC composites are double melting peaks. As the crystallization temperature increases to a high enough temperature,the crystal tends to be perfect,which has only a melting peak. Compared with pure PA11,PA11/SiC composites have a relatively low melting point.