摘要
以高密度聚乙烯(PE-HD)为研究对象,采用多种不同的分级方法对树脂进行了分级,研究了树脂的支链结构及其分布,通过升温淋洗分级法与其他技术结合的交叉分级法,建立了短链支化含量、淋洗温度、相对分子质量的三维关系图,反映了PE-HD支链结构的分布特征。结果表明,PE-HD树脂由4部分构成:含有一定数量支链的低分子蜡部分;短支链数目较多的线形低密度聚乙烯部分,此部分随相对分子质量的增大支化度增加,且分布在高相对分子质量部分的支链含量较高;短支链数目较少的高密度聚乙烯部分,此部分短支链在不同相对分子质量区域的分布较为均匀;几乎不含支链的线形聚乙烯部分。
The high-density polyethylene（PE-HD）resin was fractionated by different methods,and its branch structure and distribution were investigated.A three-dimensional relationship graph for the short-chain branching content,elution temperature and molecular weight was established by a combination of temperature rising elution fractionation and other cross-fractionation methods,which well reflected the branch-structural distribution characteristics of PE-HD.The results indicated that the PE-HD resin was composed of four parts including a low molecular wax containing a certain amount of branch structure,apart of linear low-density polyethylene with larger short-chain branching numbers,apart of high-density polyethylene with small short-chain branching numbers,and the linear polyethylene almost without any branching chains.It was also found that the fraction of the linear low-density polyethylene increased with an increase of relative molecular weight,whereas the part of the high-density one kept a uniform molecular weight distribution.
出处
《中国塑料》
CAS
CSCD
北大核心
2018年第2期122-127,共6页
China Plastics
关键词
高密度聚乙烯
交叉分级
支链结构
相对分子质量
high-density polyethylene
cross-fractionation
branching structure
molecular weight
