Study On Preparation,Structure And Properties Of MPU Blend Rubber

In this project,the co-vulcanization of MPU(Millable Polyurethane)and other rubbers was studied.Through the study of the co-vulcanization,the influence of the micro cross density on the properties of the blend was found and summarized,and the problem of the serious degradation of the properties of the blend was effectively solved through experiments.In the study of MPU blending application,through the blending of MPU with diene polar rubber,non-polar rubber,and saturated main chain rubber,the change rules of wear resistance,medium resistance,mechanical strength and other properties were investigated.It was found that MPU blending with different rubber would present different characteristics.(1)The vulcanization system of MPU was explored,and the properties of vulcanizates with different vulcanization systems were investigated.It is found that different types of crosslinking networks have certain effects on the tensile stress of MPU.In addition,MPU has unique characteristics of performance change during thermal oxidative aging.(2)The serious degradation of properties of MPU/NR(Natural Rubber)blends was studied.Firstly,the existence of segregation in vulcanization system was verified by experiments.The segregation was gradually improved by constructing precrosslinking network and other means,and the properties of MPU/NR blends were improved.(3)The problem of insufficient co-vulcanization of MPU and NBR(Nitrile Rubber)due to the mismatch of vulcanization characteristics was studied.By means of heat treatment,the vulcanization induction period of NBR phase was consumed to achieve two-phase synchronous vulcanization,so as to improve the properties of MPU/NBR blends.(4)The effect of crosslinking density on the modulus of MPU/EPDM(Ethylene Propylene Rubber)blends and the tensile stress of MPU/EPDM blends were studied.The mathematical model was also established.The model can be used to predict the properties of MPU/EPDM blends.(5)The effect of internal friction on the properties of MPU/CM(Chlorinated Polyethylene Rubber)blends was studied.The internal friction of MPU/CM blends was reduced and the properties of MPU/CM blends were improved by step staggered temperature vulcanization.The mathematical model of the relationship between the first-order vulcanization time and the physical properties of the vulcanizates was summarized.It is of great significance to reduce the cost of MPU.