NPG用量对IPDI预聚体水分散性和力学性能的影响

Effect of NPG Content on Water Dispersibility and Mechanical Properties of IPDI Prepolymer

利用新戊二醇(NPG)甲基支链结构的特点,通过与二异氰酸酯(IPDI)反应,制得含-COOH、-NCO封端、具有甲基侧链结构特点的预聚体。在低聚物二元醇与IPDI投料比相同且不添加任何有机溶剂降黏的情况下,研究了NPG含量对预聚体水分散性和力学性能的影响。结果表明:随NPG含量的增加,预聚体黏度不断降低、便于分散在水中。当NPG含量≤2%时,即可实现预聚体水分散时无需添加有机溶剂降黏,同时满足抗水性和力学性能的要求。

Using the methyl branching structure characteristics of the neopentyl glycol (NPG), methyl branching chain is introduced into the prepolymer by reacting neopentyl glycol (NPG) with diisocyanate (IPDI) to obtain the polyurethane prepolymers having –COOH and –NCO end group and methyl branched chain structure. Under the conditons of the same mass ratio of the oligomer diol to IPDI and no additon of any organic solvent to reduce the viscosity, the effects of NPG contents on the dispersibility and the mechanical properties of the prepolymer are studied. The results show that the increase of NPG content causes the reduction of the viscosity of the prepoylmer and is beneficial for the dispersibility of prepolymer in the water. When the NPG content is less than 2%, the prepolymer can be dispersed in the water without adding organic solvents to reduce viscosity, at the same time, it can meet the demand on water resistance and the mechanical properties.