水性聚氨酯涂料的制备及性能研究

The Preparation and Performance Study of Waterborne Polyurethane Coatings

以PTMG-1000和TDI、HDI为原料制备聚氨酯预聚体,采用乳化法制备水性聚氨酯,并对漆膜硬度、附着力、分散粒度进行检验和分析。将不同配方制得的样品在转速为1200r/min、1000r/min和800r/min的强剪切力作用下分散成20%和25%浓度的乳液。硬度分析结果表明:.聚氨酯分子量链中的硬段组成芳香族TDI中含有刚性苯环可以提高漆膜的硬度,可达4H^5H,而改用HDI后硬度降低至2H^3H。附着力分析结果表明:漆膜附着力较好,为1级~2级。涂膜硬度还受分散的乳液浓度影响,浓度越高涂膜硬度越大。在不同大小的剪切力下,乳液分子粒径可以从160nm左右变化到10nm左右,分散转速越快,分子粒径越小。聚氨酯分子链硬段组成为HDI的比TDI的分子粒径小。

PTMG-1000 and the TDI,HDI as raw materials of polyurethane prepolymer prepared using Waterborne polyurethane emulsion was prepared,and coating hardness,adhesion,distributed testing and analysis of particle size.Different formulations of the samples obtained in the speed of 1200r/min,1000r/min and the strong shear force 800r/min under decentralized into 20% and 25% concentration in emulsion.Hardness analysis showed that:Polyurethane molecular weight of the hard segment chain composed of rigid aromatic benzene ring containing TDI can increase the hardness of the paint film,up to 4H ~ 5H;and after the switch to HDI hardness reduced to 2H^3H.Adhesion analysis showed that: a good film adhesion,1 ~ 2.Coating hardness was also affected by the impact of dispersed emulsion concentration,the higher the concentration the greater hardness of the coating.In the shear force of different sizes,the emulsion molecular size changes from about 160nm to about 10nm,the faster the speed of dispersion,the smaller molecular size.Polyurethane hard segment molecular chain consisting of HDI was smaller than the TDI of the molecular size.