Chem. J. Chinese Universities ›› 2018, Vol. 39 ›› Issue (10): 2312.doi: 10.7503/cjcu20180151

• Polymer Chemistry • Previous Articles     Next Articles

Fractionation and Fraction Characterization of trans-Polyisoprene Rubber Alloys within Reactor

NIU Qingtao1, ZOU Chen1, WANG Riguo2,*(), LI Lange2, HE Aihua1,*()   

  1. 1. Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization, Key Laboratory of Rubber-Plastics(Ministry of Education), School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
    2. Shandong Huaju Polymer Materials Co. Binzhou 256500, China
  • Received:2018-02-28 Online:2018-09-14 Published:2018-09-14
  • Contact: WANG Riguo,HE Aihua E-mail:wangriguo@sina.com;ahhe@qust.edu.cn
  • Supported by:
    † Supported by the National Basic Research Program of China[No.2015CB654700(2015CB354706)], the National Nature Science Foundation of China(No.51473083), the Significant Basic Research Program of Shandong Province, China(No.ZR2017ZA0304) and the Taishan Scholar Program, China.

Abstract:

Trans-1,4-polyisoprene rubber alloys(TPIR) with different butadiene incorporation catalyzed by supported titanium Ziegler-Natta catalyst within pilot plant reactor were effectively fractionated by the stepwise isothermal crystallization fractionation method. The microstructure, molecular weight(Mw) and molecular weight distribution(Mw/Mn), butadiene unit content($\bar{F}_{Bd}$), crystallization behavior and crystal form of main fractions were analyzed by 13C NMR, GPC, DSC and XRD. The results showed that trans-1,4-polyisoprene rubber alloys were mainly composed of 7 fractions(A—G). TPIR-05 with low butadiene incorporation was mainly composed of fraction C, D, G; TPIR-10 with high butadiene incorporation was mainly composed of fraction A, B, C, D, G. Fraction A having high butadiene unit content($\bar{F}_{Bd}$=22.4%, molar fraction) was gradient multi-block trans-1,4-poly(isoprene-co-butadiene) copolymers containing trans-1,4-polyisoprene(TPI) blocks and trans-1,4-polybutadiene(TPB) blocks; Fractions B, D were gradient trans-1,4-poly-(isoprene-co-butadiene) copolymers with low butadiene unit content($\bar{F}_{Bd}$=2.7%—6.5%) and long TPI blocks; fractions C were trans-1,4-polyisoprene homopolymers; fraction G were random trans-1,4-poly-(isoprene-co-butadiene) copolymers with high butadiene unit content($\bar{F}_{Bd}$=15.6%—20.4%) and weak crystallizability. The possible chain structure models for these fractions were proposed.

Key words: trans-1,4-Polyisoprene rubber alloy, Isothermal crystallization fractionation, Structure characterization, Chain structure model

CLC Number: 

TrendMD: