聚丁二酸丁二酯切片的储存稳定性

Storage stability of polybutylene succinate chips

为了探讨在工业化仓储条件下,生物可降解聚酯——聚丁二酸丁二酯(PBS)的分子量、低聚物含量、切片可加工性能的变化规律,以PBS切片为研究对象,选择真空干燥和鼓风干燥两种干燥方式,避光自然吸湿、真空日晒和真空避光三种储存方式对样品进行干燥和长期储存。系统分析了不同干燥及储存条件对PBS特性黏度、熔体流动性、含水率及低聚物含量的影响。结果表明,与真空干燥相比,鼓风干燥方式可以更快速地干燥PBS样品,在干燥24 h时含水率已降至2.45‰,且样品特性黏度下降较少,熔体流动速率未有显著增加。各储存条件下,随着储存时间的延长,样品内可挥发物含量均有增加。对于黏均分子量,真空日晒对PBS样品分子量的影响显著强于避光自然吸湿。短期储存PBS样品(21 d及以内),真空避光保存可以更好地保持PBS原有的分子量、熔体流动速率,且能有效降低PBS切片中低聚物的析出。

In order to explore the change pattern of molecular weight,oligomer content,and chip processability of biodegradable polyester polybutylene succinate(PBS)under industrialized storage conditions,two drying modes of vacuum drying and blast drying,and three storage modes of avoid light and absorb moisture naturally,vacuum sun exposure and vacuum light avoidance were chosen to dry and store the samples for a long period of time,with the PBS chips as the research object.The effects of different drying and storage conditions on the intrinsic viscosity,melt flow,water content and oligomer content of PBS were systematically analyzed.The results show that compared with the vacuum drying,the blast drying method can dry the PBS chips more quickly,and the water content has been reduced to 2.45‰at 24 h.The decrease of the characteristic viscosity of the samples is small,and the melt flow index do not increase significantly.The content of volatiles within the samples increase with increasing storage time for each storage condition.For viscous average molecular weight molecular weights,the effect of vacuum sun exposure on the molecular weight of the PBS chips is significantly stronger than that of avoid light and absorb moisture naturally.Short-term storage of PBS chips(21 days or less),vacuum light avoidance can better maintain the original molecular weight and melt flow index of PBS,and can effectively reduce the precipitation of oligomers in PBS chips.