At low temperatures,the adhesive's adhesion is weakened,which affects its adhesion to the surface of the adherend.Therefore,the preparation and performance of high transparency polyurethane adhesive at low temperature are studied.The polyester polyols are used as important raw materials,a high transparency polyurethane adhesive is prepared by mixing multiple additives by the prepolymer method.The effect of diluent dosage on the viscosity,compressive strength and shear strength of polyurethane at low temperature is analyzed.The effect of curing agent type on the mechanical properties of polyurethane at low temperature is tested,as well as the effect of low temperature duration and freeze-thaw cycle on the ten-sile strength of polyurethane.The experimental results show that when the diluent dosage is 20%,the viscosity of polyurethane is higher and the com-pression and shear strength are more stable in low-temperature environments;After selecting TDI+HDI curing agent,the polyurethane exhibits high mechanical properties in low-temperature environments.After the low-temperature treatment for 6 h,the polyurethane maintains stable tensile strength and strong low-temperature resistance.After 70 freeze-thaw cycles,the tensile strength is basically stable and will not undergo serious damage.
关键词
低温环境/高透明/聚氨酯/胶粘剂/压缩强度/冻融循环
Key words
low temperature environment/high transparency/polyurethane/adhesive/compressive strength/freeze-thaw cycle