高韧耐热PLA/PBS共混材料的制备及性能

Preparation and Properties of PLA/PBS Blends with High Toughness and Heat Resistance

首先以聚丁二酸丁二酯(PBS)为增韧剂、反应型扩链剂苯乙烯-甲基丙烯酸缩水甘油酯(ADR)为增容剂对聚乳酸(PLA)进行增韧,制备PLA/PBS/ADR共混物。通过扫描电子显微镜(SEM)和万能试验机等对材料的形貌和性能进行了表征和测试,结果显示,当PLA与PBS的质量比为80∶20时,缺口冲击强度为4.6kJ/m^(2),比纯PLA增长了64.3%。拉伸强度为40.8MPa。而当PLA和PBS的质量比为80∶20,ADR的含量为PLA和PBS总质量的1%时,共混物的缺口冲击强度达到32.8kJ/m^(2),断裂伸长率为255%,较PLA分别提高了近11倍和45倍。从SEM可以看出,加入ADR可以增强两相的相容性。随后,对ADR质量分数为1%的样品进行等温退火处理,相比于未热处理样品,其耐热性能显著提高。同时,其在基体PLA结晶完全时缺口冲击强度达到最高,为56.1kJ/m;。基体PLA结晶完全之后继续增加热处理时间,样品缺口冲击强度均降低。

By using polybutylene succinate(PBS)as toughening agent and reactive chain extender styrene-glycyl methacrylate(ADR)as compatibilizer to toughen polylactic acid(PLA),PLA/PBS/ADR blends were prepared.The morphology and properties of the materials were characterized and tested by scanning electron microscopy(SEM)and universal testing machine.When the mass ratio of PLA to PBS is 80∶20,the impact strength of PLA/PBS blends is 4.6 kJ/m~2,which is 64.3%higher than that of pure PLA.The tensile strength is 40.8 MPa.When the mass ratio of PLA to PBS is 80∶20 and the content of ADR is 1%,the notched Izod impact strength and elongation at break of the blend reach 32.8 kJ/m~2 and 255%,which are nearly 11 times and 45 times respectively compared with PLA.Moreover,it can be seen from SEM that adding ADR can enhance the phase interface between the two phases.Subsequently,isothermal annealing treatment was carried out on the increased volume samples,significantly improving the heat resistance of the samples compared with the samples without heat treatment.At the same time,the notched izod impact strength reaches the highest value of 56.1 kJ/m~2 when PLA is crystallized completely.After increasing the heat treatment time,the notched izod impact strength of samples decrease.