光学微流变法研究液化改性二苯基甲烷二异氰酸酯(MDI)与反应性

Study on Liquefaction Modification and Reactivity of Diphenylmethane Diisocyanate (MDI) by Optical Microrodulus

摘要: 利用光学微流变研究液化改性二苯基甲烷二异氰酸酯(MDI)与反应性。通过单羟基小分子醇、聚丙二醇(PPG)与4,4’-二苯基甲烷二异氰酸酯(MDI)反应制备出了低黏度液化改性MDI，并对其反应性进行了研究。研究了MDI、PPG和单羟基小分子醇之间的摩尔比及PPG分子量变化对液化改性MDI的表观特性、稳定性及其反应活性的影响，结果表明，MDI/单羟基小分子醇摩尔配比在8.0~10.0和MDI/大分子多元醇摩尔配比在18.0~21.0范围内，得到黏度为310~360 mPa·s、NCO质量分数为18%~21%、稳定的液化MDI，PPG分子量的变化对液化改性MDI黏度影响较小，液化改性MDI反应活性高、可以形成较好的交联网络聚合物。

Abstract: The reactivity of modified diphenyl methane diisocyanate (MDI) and its reactivity were studied by optical microrheology. The low viscosity liquefied MDI was prepared by the reaction of monohydroxy small molecule alcohol, polypropylene polyol (PPG) with MDI. The effects of the molar ratio of MDI/PPG/mono hydroxyl alcohol and the change of molecular weight of PPG on the apparent properties, stability and reaction activity of MDI modified by liquefaction were studied. The results showed that liquefaction modification with the NCO content of 18% to 21%, viscosity in the range of 310 to 360 mPa∙s obtained under condition of the molar ratio of MDI/monohydroxy small molecule alcohol is in the range of 8.0~10.0 and the molar ratio of MDI/macroalcohol in the range of 18.0~21.0. PPG molecular preparation of liquefied MDI viscosity has few effects. The results also showed that liquefied modified MDI could react well and form better crosslinked network polyme.