摘要
稀土顺丁橡胶(LnBR)与钛,钴和镍系BR在结构上的主要差别是:LnBR的顺式-1,4结构含量大于98%,分子链一般无支化,线形度高,分子量分布宽((?)_w/(?)_n=4~6)。实验表明。分子量分布过宽会导致其加工性尤其是挤出性能下降,而分子量分布较窄((?)_w/(?)_n≈4)者,则其硫化胶的物理机械性能优于其他BR硫化胶。用LnBR制造充油胶,基础胶的特性粘数以4.5~5.5dL/g为宜。
The main differences in macromolecule struc ture of rare-earth polybutadiene rubber (LnBR) with TiBR , CoBR and NIBR consist in : (1) LnBR possesses extremely high cis- 1,4 unit content ,usually more than 98% ; (2) There is almost no sigh of the existence of branched macromolecules in LnBR ; (3) The molecular weight distribution (MWD) is very broad (Mw/ Mn=4 - 6). Results showed that broad MWD deteriorated the processability of LnBR , especially its extruding property . Mechanical properties of LnBR having narrower MWD (MW/Mn≈4) were excellent , superior to any kind ofcommercially manufactured BRs . It is due to the high degree of regularity of its macromolecule structure. Manufacturing the oil-extended LnBR, the optimum range of its intrinsic viscosity was 4.5 to 5.5. In this case , the influence of MWD of the basic LnBR on the proper ties of the oil-extended LnBR was very consider able .
出处
《合成橡胶工业》
CAS
CSCD
北大核心
1993年第2期77-81,共5页
China Synthetic Rubber Industry
关键词
稀土催化剂
链结构
性能
顺丁橡胶
rare-earth catalyst
cis-1,4- polybutadiene
oil-extended rubber
chain struc- ture
molecular weight distribution
relation be- tween structure and properties