%0 Journal Article
%T 13C-NMR STUDY ON THE STEREOSEQUENCE DEFECTS IN HIGH ISOTACTICITY POLYPROPYLENE<br>13C-NMR研究高全同立构聚丙烯的立构缺陷
%A Zhu Shan-nong
%A Yang Xiao-zhen
%A <br>朱善农
%A 杨小震
%J 高分子学报
%D 1984
%I 
%X Chemical shifts relating to methyl carbon of central group in the undecad situated within an otherwise isotactic polypropylene chain were calculated by using Gamma effects, Suter and Flory's rotational polypropylene model. All meso, single, double and tetra racemic (r) defects in the undecad were designed.By comparing the chemical shifts calculated from experimental 67.8 MHz 13C-NMR spectra data indicated that the main stereo-defects are isolated rr triads in predominantly isotactic polypropylene chain and the long rrrr sequence,but do not isolated rrrr pentad distri-buted in the isotactic polypropylene chain.
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=6579068328FE643F&jid=15971983683C7643EE80F1CE621DEB60&aid=B12B0D8130F1CCD8&yid=36250D1D6BDC99BD&iid=38B194292C032A66&sid=2BA123C6EB9D54C2&eid=BC084ACE66B62CC8&journal_id=1000-3304&journal_name=高分子学报&referenced_num=0&reference_num=0