输液管用SEBS高效低毒抗氧体系的研究

The Study of Efficient and Low Toxicity Antioxidant of Infusion Tubes SEBS

以多次挤出、加速降解为评价方式,采用全自动白度仪、凝胶渗透色谱(GPC)、电子万能测试机、傅立叶变换红外光谱仪(FTIR)以及差示扫描量热分析仪(DSC)等手段,研究了不同抗氧剂对聚苯乙烯氢化二烯烃嵌段共聚物(SEBS)稳定性的影响。结果表明,纯SEBS的热稳定性差,经5次热加工后,氧化诱导期由初始的14.6min降到5.4 min,黄色指数从15.16增大至27.45,摩尔质量分布宽度从1.232增加到1.540,力学性能则降低至初始值的50%,且在热氧和剪切的作用下,SEBS易发生氧化降解生成羟基、羰基等含氧基团。加入四种不同抗氧体系后,输液管用SEBS的热稳定性均有一定程度的提高,而添加高效低毒抗氧体系E330/168的输液管用SEBS的热稳定性最好,随热加工次数增加,黄色指数无明显变化;经5次热加工后的重均摩尔质量为11.15万g/mol,较未加抗氧剂的SEBS高42%,摩尔质量分布为1.256,较未加抗氧剂的低18%;抗氧体系E330/168有效地抑制了SEBS在加工过程中的氧化降解,从而使其各项性能得到良好的保持。相对抗氧剂1010和626,抗氧剂E330/168不仅高效,而且具有低毒性、低致畸性和低水溶性,更适用于输液管用SEBS。

With multi-extrusion and degradation acceleration,the effects of different antioxidants on the stability of SEBS were tested by automatic whiteness meter, gel permeation chromatography（ GPC）,electronic universal testing machine, Fourier transform infrared spectroscopy（ FTIR） and scanning calorimetry analyzer（ DSC）.The results were the following： the thermal stability of SEBS was bad.The oxidation induction period of SEBS reduced from 14.6 min to 5.4 min and the yellow index of SEBS increased from 15.16 to 27.45 after the fifth thermal processing,the molecular weight distribution increased from 1.232 to 1.540,in addition,the mechanical properties decreased to 50% of the initial.It was easy for SEBS to oxide and degrades and generates oxygen-containing groups such as carbonyl and hydroxyl under the condition of heat,oxygen and shear.After adding four different antioxidants,thermal stability of SEBS infusion tubes has improved significantly,but after adding composite efficient antioxidants,the thermal stability of SEBS was the best.With processing times increasing,the yellow index nearly didn＇t change obviously ,moreover,after the fifth thermal processing,the weight average molecular weight was 1.115 million and it was 42%higher than that of SEBS without antioxidants; molecular weight distribution was 1.256 which was 18% lower than that of SEBS without antioxidants.Antioxidants E330/168 effectively inhibited oxidation and degradation of SEBS during processing,so it maintained the good performance of SEBS.Compared to the antioxidant1010 and 626,complex and antioxidant E330 and 168 has a low toxicity,low teratogenicity and low water solubility,which were more suitable for infusion tubes SEBS.