摘要
采用自制装置对聚碳硅烷(PCS)熔体进行预处理。通过预处理获得三种不同分子量的PCS,并对其进行物理化学和稳态流变性能测试。结果表明,预处理后的PCS其数均分子量为1000 g/mol^1400 g/mol,属低聚物。在温度范围240℃~260℃和剪切速率范围0.001 s-1~10 s-1内有明显的剪切变稀现象。在测试的温度范围内,剪切变稀区的非牛顿指数随温度升高先减小后增大。预处理后的PCS粘流活化能为120 kJ/mol^180 kJ/mol,比一般高聚物的高得多。
A self-made deaeration apparatus was constructed to minimize the small bubbles of polycarbosilane （PCS） melts resulted at high temperatures. Three types of PCS samples with different numbers of average molecular weight （Mn） after the pre-treatment were obtained. The M^-n values varied from 1000 g/mol to 1400 g/mol, suggesting the nature of low polymers. The physical and chemical properties, as well as the steady-state theological properties of pre-treated and raw PCS samples were examined and compared. The results show that the PCS melts exhibit typical shear shinning phenomenon in 240 ℃ -260 ℃. The values of non-Newtonian index （ n ） first decrease and then increase with increasing temperature in the shear shinning region. The viscous flow activation energy （En） ranges 120 kJ/mol-180 kJ/mol, which is higher than those of common polymers.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2009年第7期53-56,共4页
Polymer Materials Science & Engineering
基金
国家自然科学基金资助项目(50532010)
福建省特种先进材料重点实验室基金资助项目(2006L2003)
关键词
聚碳硅烷
预处理
流变性能
粘流活化能
polycarbosilane
pre-treatment
rheological properties
viscous flow activation energy
