CIESC Journal ›› 2017, Vol. 68 ›› Issue (3): 1247-1252.DOI: 10.11949/j.issn.0438-1157.20161013

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Macromolecular post-chain extension study of TDI-based waterborne polyurethane dispersions with ethylene diamine

FAN Renxiang1, CHEN Dingding1, LI Jiajin1, DING Yunsheng1,2   

  1. 1 School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009, Anhui, China;
    2 Key Laboratory of Advanced Functional Materials and Devices, Hefei 230009, Anhui, China
  • Received:2016-07-20 Revised:2016-11-21 Online:2017-03-05 Published:2017-03-05
  • Contact: 10.11949/j.issn.0438-1157.20161013
  • Supported by:

    supported by Key Project of Anhui Province (1301021016) and AVIC Beijing Institute of Aeronautical Materials (cxy2012HFGD24).

乙二胺后扩链TDI型聚氨酯水分散体的过程

范仁祥1, 陈丁丁1, 李嘉晋1, 丁运生1,2   

  1. 1 合肥工业大学化学与化工学院, 安徽 合肥 230009;
    2 先进功能材料与器件安徽省重点实验室, 安徽 合肥 230009
  • 通讯作者: 丁运生,dingys@hfut.edu.cn
  • 基金资助:

    安徽省重点攻关项目(1301021016);中国航空工业集团产学研项目(cxy2012HFGD24)。

Abstract:

A series of polyurethane aqueous dispersions, which were prepared from raw materials of toluene diisocyanate (TDI), polypropylene glycol (PPG), and dimethylol propionic acid (DMPA), were used to study post-chain extension process with ethylene diamine (EDA) as chain extender, including factors of H2O, temperature of post-chain extension, molar ratio of -NCO/-OH in raw materials, and chain extension ratio. FT-IR results showed that the post-chain extension process of polyurethanes with EDA was affected by H2O in aqueous dispersion through competitive reactions of H2O with residual -NCO groups in polyurethane chains. Measurement of molecular weight, particle diameter, and zeta potential of polyurethane dispersions before and after chain extension indicated that chain extension by H2O resulted in instability of polyurethane dispersions. The influence of H2O on EDA post-chain extension process was significant at low chain extension ratio, whereas molecular weight of chain-extended polyurethanes was lowered at high chain extension ratio. When chain extension temperature was increased, molecular weight of EDA chain-extended polyurethanes was decreased,but diameters of polyurethane dispersions were increased. With molar ratio of -NCO/-OH in raw materials at 1.20, chain extension temperature at 30℃, and chain extension ratio at 60%, the H2O impact on post-chain extension of polyurethanes with EDA was reduced effectively.

Key words: polyurethane, dispersion, toluene diisocyanate, water, post-chain extension, chain extension ratio, particle size distribution

摘要:

以甲苯二异氰酸酯(TDI)、聚氧化丙烯二醇和二羟甲基丙酸等为主要原料制备了聚氨酯水分散体,研究了水、扩链温度、原料的-NCO/-OH摩尔比及扩链比对乙二胺(EDA)后扩链TDI型聚氨酯水分散体过程的影响。FT-IR测试表明,分散体中的H2O可通过与聚氨酯中残留异氰酸酯基团(-NCO)的竞争反应影响EDA的后扩链过程。分子量及粒径与zeta电位测试表明,H2O扩链导致分散体失稳;低扩链比时,H2O对EDA的后扩链过程影响明显,但高扩链比时,后扩链聚氨酯的分子量降低;扩链温度升高,经EDA后扩链聚氨酯的分子量降低,而分散体粒径增大。当原料的-NCO/-OH摩尔比为1.20、扩链温度为30℃、扩链比为60%时,可有效降低H2O对EDA后扩链聚氨酯过程的影响。

关键词: 聚氨酯, 分散体, 甲苯二异氰酸酯, 水, 后扩链, 扩链比, 粒度分布

CLC Number: