为了更充分地了解微量水对聚氨酯预聚反应及预聚体结构的影响,用一步法首先合成了聚氨酯初始预聚体,然后研究了微量水及扩链温度等对聚氨酯预聚体的特性粘数、在THF中的溶解性和分子量分布等的影响,采用FT-IR对水扩链预聚体的聚集态结构进行了初步的研究.研究结果表明,水和—NCO基团反应生成聚脲结构,表现在聚氨酯硬段间的氢键作用增强,而硬段与软段间的氢键作用力减弱.微量水的存在可以对聚氨酯预聚体起到扩链作用,但随水量的增加预聚体会生成交联结构,产生不溶性凝胶.聚合温度的提高会加速聚脲结构的形成.
参考文献
| [1] | Vanderlaan MN.;Thring RW. .Polyurethanes from Alcell (R) lignin fractions obtained by sequentialsolvent extraction[J].Biomass & Bioenergy,1998(5/6):525-531. |
| [2] | Jang JY.;Jhon YK.;Cheong IW.;Kim JH. .Effect of process variables on molecular weight and mechanical properties of water-based polyurethane dispersion[J].Colloids and Surfaces, A. Physicochemical and Engineering Aspects,2002(2/3):135-143. |
| [3] | Wang, Y.;Ruan, C.;Sun, J.;Zhang, M.;Wu, Y.;Peng, K. .Degradation studies on segmented polyurethanes prepared with poly (d, l-lactic acid) diol, hexamethylene diisocyanate and different chain extenders[J].Polymer Degradation and Stability,2011(9):1687-1694. |
| [4] | Ajaya K.Nanda;Douglas A.Wicks .The influence of the ionic concentration,concentration of the polymer,degree of neutralization and chain extension on aqueous polyurethane dispersions prepared by the acetone process[J].Polymer: The International Journal for the Science and Technology of Polymers,2006(6):1805-1811. |
| [5] | Azzam, RA;Mohamed, SK;Tol, R;Everaert, V;Reynaers, H;Goderis, B .Synthesis and thermo-mechanical characterization of high performance polyurethane elastomers based on heterocyclic and aromatic diamine chain extenders[J].Polymer Degradation and Stability,2007(7):1316-1325. |
| [6] | 张晓彦,罗彦凤,阮长顺,王品品,窦庶华,王远亮.哌嗪扩链的形状记忆医用材料聚氨酯脲的合成与表征[J].功能材料,2012(08):1008-1011. |
| [7] | Jhon YK.;Kim JH.;Cheong IW. .Chain extension study of aqueous polyurethane dispersions[J].Colloids and Surfaces, A. Physicochemical and Engineering Aspects,2001(1):71-78. |
| [8] | 刘益军.聚氨酯树脂及其应用[M].北京:化学工业出版社,2011:22. |
| [9] | 熊军,孙芳,杜洪光.丙酮-二正丁胺滴定法测定聚氨酯中的异氰酸酯基[J].分析试验室,2007(08):73-76. |
| [10] | 复旦大学高分子科学系;分子科学研究所.高分子实验技术[M].上海:复旦大学出版社,1996:24-25. |
| [11] | Mishra AK;Chattopadhyay DK;Sreedhar B;Raju KVSN .FT-IR and XPS studies of polyurethane-urea-imide coatings[J].Progress in Organic Coatings: An International Review Journal,2006(3):231-243. |
| [12] | Mattia J;Painter P .A comparison of hydrogen bonding and order in a polyurethane and poly(urethane-urea) and their blends with poly(ethylene glycol)[J].Macromolecules,2007(5):1546-1554. |
| [13] | Mohammad Mizanur Rahman;Han-Do Kim;Won-Ki Lee .Properties of Waterborne Polyurethane Adhesives: Effect of Chain Extender and Polyol Content[J].Journal of Adhesion Science and Technology: The International Journal of Theoredtical and Basic Aspects of Adhesion Science and Its Applications in All Areas of Technology,2009(1):177-193. |
| [14] | Ravat B;Oudot B et al.Electron irradiation of polyurethane using UV spectroscopy,GPC and swelling analyses[J].Radiation Physics and Chemistry,2002,63(01):93-99. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%