水性聚氨酯分散液的合成与研究

SYNTHESIS AND RESEARCH OF WATER-BORNE POLYURETHANE

采用二级扩链技术 ,合成了同时具备阴离子型和非离子型大分子链结构的水性聚氨酯分散液 ;以红外光谱法作为半定量分析手段 ,进行了预聚过程动力学的研究 ,认为当初始合成温度为 70℃时 ,以丁酮为稀释剂 ,DMPA为离子型亲水单体 ,乙二醇为一级扩链剂 ,三乙胺为中和剂 ,三次乙基四胺为二级扩链剂 ,当n(NCO) /n (OH) =1 5时 ,预聚反应 5h ,扩链反应 2～ 4h ,可获得具有良好稳定性的水性聚氨酯分散液 ;超速离心沉降试验进一步证实了该结果。

In order to obtain a better synthesizing way of water borne polyurethane(WBPU)dispersion,the water borne polyurethane(WBPU)whose macromolecular chain structure combines of anionic and nonionic types,was prepared by a new technology of second order expanded chain.Quasi quantitative analytical method of FT IR spectra was adopted to study on the kinetics of pre polymerization process,and the stable WBPU dispersion was obtained in the following optimal condition:70 ℃,dimethylolpropionic acid(DMPA)as ionic hydrophilic monomer,polyethylene glycol(PEG)as first order expanded chain agent,triethylamine(TEA)as neutralizing agent,triethylenetetramine(TETA)as second order expanded chain agent, n \{(NCO)\}/ n \{(OH)\}=1 5,prepolymerization period 5 h,and expanded chain period 2～4 h The results of the ultracentrifugation sedimentation test proved its stability.