Quantitative IR characterization of urea groups in waterborne polyurethanes
Quantitative IR characterization of urea groups in waterborne polyurethanes
复制标题
DOI：
10.1002/pola.22577
复制
发表时间：
2008-04
期刊：
影响因子：
--
通讯作者：
Ying Shi;Xiao-li Zhan;Z. Luo;Qinghua Zhang;Feng-qiu Chen
中科院分区：
文献类型：
--
作者：
Ying Shi;Xiao-li Zhan;Z. Luo;Qinghua Zhang;Feng-qiu Chen
本研究的目的是建立水性聚氨酯（pu）的红外光谱与尿素组分之间的相关性，以研究聚合过程中的副反应，即异氰酸-水反应。该方法是基于在amide I范围内（即1600-1800 cm−1）的光谱分解，其中感兴趣的波段重叠。利用傅立叶自反褶积（FSD）和高斯曲线拟合技术对该区域存在的几个单独的波段进行了分辨，并确定了聚氨酯CO与尿素CO的强度比。为了实现定量测量，以一些聚氨酯-尿素样品为标准，用1H NMR进行表征，建立了校准曲线。用核磁共振氢谱测定了脲基与脲基的浓度比。IR和1H NMR测量结果之间有良好的相关性。采用IPDI与二醇的微乳液聚合法制备了水性pu。定量红外光谱分析表明，乙烯基单体作为多加成溶剂对异氰酸-水反应有抑制作用，且该副反应受乙烯基单体亲水性的影响。©2008 Wiley期刊公司[J] .化学工程学报，2008,31 (4):444 - 444
The purpose of this study is to propose a correlation between IR spectra and the urea fraction of waterborne polyurethanes (PUs) to investigate the side reaction, that is, isocyanate–water reaction, during polymerization. This method is based on the decomposition of the spectrum in amide I range, that is, 1600–1800 cm−1, where the bands of interest overlap. Several individual bands present in this region were resolved by employing Fourier self-deconvolution (FSD) and Gaussian curve-fitting techniques, and the intensity ratio of urethane's CO to urea's CO was determined. To realize some quantitative measurements, a calibration curve was established with some polyurethane-urea samples, characterized by 1H NMR, which were used as standards. The concentration ratios of urethane groups to urea groups were determined from 1H NMR. A good correlation was evidenced between IR and 1H NMR measurements. Moreover, waterborne PUs were prepared by miniemulsion polymerization of IPDI with diols. From quantitative IR analysis, it was shown that a vinylic monomer, as a solvent of polyaddition, restrained the isocyanate–water reaction, and this side reaction was influenced by the hydrophilicity of the vinylic monomers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2433–2444, 2008