Research On High Toughness And Impact Resistance Structure Hemming Adhesive For Vehicle

In order to meet the development trend of consumers' increasing requirements for automobile safety,automotive designers have also put forward new requirements for hemming adhesives for automobile steel plates.The original automobile hemming adhesive only used the shear strength and T-peel strength to measure the strength and toughness of the adhesive,but when measuring the safety of a car in a crash,these two indicators are far from enough.The new standard proposes "high-toughness and impact-resistant hemming structure adhesive"(hereinafter referred to as "adhesive"),and further requires impact strength indicators of-40 ?and 80 ?.The new standard is an upgrade of the original hemming adhesive standard,and also brings new challenges to the raw material system.In order to meet the new requirements,it is necessary to redevelop the high-toughness and impact-resistant hemming structural adhesive.In this study,the test method for impact strength,the specifications of the steel panel and the test conditions were first determined.Then selected special epoxy resin materials that can meet the required impact strength,and the selection of various components in the adhesive formula.As an enterprise production formula,this study also needs to consider the cost of the formula,so that the adhesive can not only meet the requirements of the new standard,but also have market competitiveness.This paper examines and uses a revolution mixer.This type of mixer not only shortens the material mixing time,but also saves the amount of material used.When mixing materials by this method,the amount of raw materials used is only one-tenth that of conventional methods.In the process of material selection,the impact strength indicators of core-shell rubber toughened epoxy resin,nano-rubber modified epoxy resin,polyurethane modified epoxy resin,and high and low temperature resistance were studied.Materials with better strength and materials with better low temperature impact strength are used as the main materials.After selecting the appropriate materials,the formulation ratio was optimized through the double planetary agitator process.First determine the proportion of the host material,and then further determine the proportion of other components in the formula according to the proportion of the host material.At the same time,the physical and chemical properties of the material and the processing technology were taken into account,and the appropriate formula system was finally determined.Considering the robotic construction of the adhesive,the particle size and amount of glass beads in the formula were determined by the ratio of glass beads and the indentation on the steel panel.In this study,a high-toughness,impact-resistant hemming structural adhesive for vehicles based on domestic materials was successfully developed.The successful development and production of this adhesive has injected new impetus into the autonomy of intellectual property rights in the Chinese automotive adhesive industry.