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用熔融共混法制备了聚己内酯(PCL)/纳米CaCO3复合材料,考察了纳米CaCO3对PCL结晶性能和纳米CaCO3含量对PCL/纳米CaCO3复合材料力学及形状记忆性能的影响。DSC结果显示纳米CaCO3对PCL的成核结晶有一定促进作用,辐照交联使PCL的结晶熔融温度和开始结晶温度分别提高3~5℃和2~5℃;DMA结果显示复合材料的模量随纳米CaCO3含量增加而增大,但高于40%后基本无变化。纳米CaCO3含量在5%~15%范围内能明显提高PCL的拉伸强度、弯曲强度和杨氏模量;辐照交联也起到增强各组分复合材料力学性能的作用,其变化的规律与交联前一致。复合材料经辐照交联后具有形状记忆特性,随着纳米CaCO3含量的增加,形变后的材料在熔融温度下开始回复所需时间缩短,回复速率加快,所有组成的样品在所测试的实验条件下最终回复率达97%以上。扫描电子显微镜观察表明纳米CaCO3粒子在PCL基质中无明显团聚现象。
Polycaprolactone (PCL) / nano-CaCO3 composites were prepared by melt blending method. The effects of nano-CaCO3 on the mechanical properties and shape memory properties of PCL / nano-CaCO3 composites were investigated. DSC results showed that nano-CaCO3 promoted the nucleation and crystallization of PCL. Radiation cross-linking increased the crystal melting temperature and initial crystallization temperature of PCL by 3 ~ 5 ℃ and 2 ~ 5 ℃, respectively. DMA results showed that the modulus of composite With the increase of nano-CaCO3 content increases, but higher than 40% after almost no change. The nano-CaCO3 content in the range of 5% ~ 15% can significantly improve the tensile strength, flexural strength and Young’s modulus of PCL; irradiation crosslinking also play a role in enhancing the mechanical properties of the various components of the composite material, and its variation Same as before crosslinking. As the nano-CaCO3 content increases, the time required for the deformed material to begin to recover at the melting temperature is shortened and the recovery rate is accelerated. All the samples with the shape memory property under the experimental conditions tested Under the final response rate of 97% or more. Scanning electron microscopy showed that nano-CaCO3 particles in the PCL matrix no significant agglomeration.