辐射交联顺1,4-聚丁二烯的NMR研究

用１３Ｃ ＮＭＲ方法，测定了辐射交联顺１，４ 聚丁二烯在室温下的自旋 晶格弛豫时间（Ｔ１），核Ｏｖｅｒｈａｕｓｅｒ因子（ＮＯＥ），和１３Ｃ ＮＭＲ线宽．以及凝胶本体１Ｈ ＮＭＲ的Ｔ１和Ｔ２弛豫时间，结果表明，辐射交联顺１，４ 聚丁二烯体系中，随着凝胶含量的增加各碳核质子的Ｔ１值变化很小，而—ＣＨ２—核的ＮＯＥ因子明显降低和１３Ｃ ＮＭＲ线宽增宽．以及１Ｈ ＮＭＲ的Ｔ１和Ｔ２表现的双指数弛豫特性反映了交联体系中大分子链段长程运动受阻以及饱和交联叔碳核—ＣＨ对链段运动的影响．

STUDIES ON RADIATION INDUCED CROSSLINKED cis 1,4 POLYBUTADIENE BY 13 C NMR

C NMR spin lattice relaxation times ( T 1), line widths, nuclear Overhauser effcts (NOE) at room temperature have been measured for radiation induced crosslinked cis 1,4 polybutadiene. As crosslinking increases T 1 is almost invariant, line width of —CH 2— group increases markedly, NOE ratio of —CH 2— group decreases significantly too.This implies that long range chain segment motion is hindered and —CH is produced in crosslinking cis 1,4 polybutadiene.