Polymer Testing ( IF 5.1 ) Pub Date : 2020-12-08 , DOI: 10.1016/j.polymertesting.2020.107011 Weiping Zheng , Meichen Han , Yuanjin Zhao , Huafeng Shao , Aihua He
High isotactic polybutene-1 (HiPB) plays important roles in presenting outstanding resistance to creep and crack at high temperature. Therefore, rapid and accurate measurement of the HiPB is extremely important for both synthesis and application of polybutene-1 (PB). In this work, solvent extraction fractionation with diethyl ether (DE) and n-hexane (C6) as solvents (DE-C6 method) and an improved fractionation method combining isothermal crystallization and solvent extraction with xylene (Xyl) and n-pentane (C5) as solvents (Xyl-C5 method) were used to fractionate PB samples. The carbon-13 nuclear magnetic resonance spectrometry (13C-NMR), gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) were used to conduct the composition analysis of PB original samples and PB fractions. It was found that the DE-C6 method was greatly depended on the molecular weight of the fractions, while the Xyl-C5 method was biased on the isotacticity of PB fractions and fractionated PB samples into atactic PB (aPB), medium isotactic PB (MiPB) and HiPB, which showed independence on the molecular weight of fractions. Therefore, the Xyl-C5 method is recommended for more accurate measurement and isolation of HiPB fractions from PB samples.
中文翻译:
聚丁烯-1高全同立构规整度测量的一种改进方法
高等规聚丁烯-1(HiPB)在表现出出色的耐高温蠕变和开裂性能方面起着重要作用。因此,快速准确地测量HiPB对于聚丁烯1(PB)的合成和应用都极为重要。在这项工作中,以乙醚(DE)和正己烷(C6)为溶剂的溶剂萃取分馏(DE-C6方法),以及一种改进的分馏方法,将等温结晶和溶剂萃取与二甲苯(Xyl)和正戊烷(C5)结合在一起)作为溶剂(Xyl-C5方法)用于分馏PB样品。碳13核磁共振光谱仪(13使用C-NMR),凝胶渗透色谱(GPC)和差示扫描量热法(DSC)进行PB原始样品和PB馏分的组成分析。结果发现,在DE-C6方法大大依赖于级分的分子量,同时的Xyl-C5方法偏向于PB级分的等规度和分馏PB样品放入无规PB(一个PB),介质等规PB( MiPB)和HiPB,它们对馏分的分子量显示出独立性。因此,建议使用Xyl-C5方法更准确地测量和分离PB样品中的HiPB馏分。