不同紫外线吸收剂在聚碳酸酯中的应用对比

Comparison of Application of Different UV Absorbers in Polycarbonate

聚碳酸酯(PC)作为工程塑料广泛应用于室外,在太阳光长期暴晒下会发生光氧老化,影响使用性能。为了延长制品寿命,采用3种紫外线吸收剂通过共混挤出的方式与PC共混挤出造粒,对比分析了3种紫外线吸收剂的热稳定性和与抗氧剂的配伍性,并且分析了紫外线吸收剂种类与用量对PC性能的影响,研究其在PC中的使用性能。采用紫外老化试验箱进行人工加速老化,研究了紫外线吸收剂应用于PC中的抗紫外老化效果,从而得到适用于PC的紫外线吸收剂。结果表明:紫外线吸收剂1UV在PC加工温度条件下的热损失率较大,热稳定性较差,初期易着色;紫外线吸收剂2UV和3UV对PC使用性能影响较小,但用量过高会使其黄色指数升高,影响制品的外观色泽;在紫外老化过程中紫外线吸收剂2UV和3UV对PC的颜色有很好的保护作用,2UV对PC韧性保护比3UV效果更好。

Polycarbonate(PC), as an engineering plastic, is widely used outdoors. Under long-term exposure to sunlight, it will undergo photo oxidative aging, which affects its performance. In order to extend the service life of the product, three types of UV absorbers were used to blend and extrude with PC for granulation. The thermal stability and compatibility with antioxidants of the three types of UV absorbers were compared and analyzed. The impact of the type and amount of UV absorbers on the performance of PC was also analyzed, and its performance in PC was studied. A UV aging chamber was used for artificial accelerated aging, and the anti UV aging effect of UV absorbers applied to PC was studied, in order to obtain UV absorbers suitable for PC. The results show that UV absorber 1UV has a high heat loss rate and poor thermal stability under the processing temperature conditions of PC, making it easy to color in the initial stage. The impact of UV absorbers 2UV and 3UV on the performance of PC is relatively small, but excessive use will increase its yellow index, affecting the appearance and color of the product. During the UV aging process, UV absorbers 2UV and 3UV have a good protective effect on the color of PC, and 2UV provides better protection for PC toughness than 3UV.