Preparation Of Natural Rubber Foam And A Study On Its Structure And Properties

Rubber foam or sponge is a porous material which has a unique structure. The large a mount of pores existed in the matrix reduce the weight of materials thus significantly broaden its application in the field of engineering. Rubber foam material is a traditional material, which has long been used in the field of structural, insulation and damping areas because of its excellent mechanical properties. However research on the rubber foam material is insufficient and mostly empirical. In this paper we aim at leading an in-depth and quantitative study into the preparation of foamed rubber and the relationship between its structure and properties.In the manufacturing process of foamed rubber there are two simultaneously occurring reaction---the curing of the rubber and the decomposition of the blowing agent. Whether these two processes are in good match is the key factor of manufacturing high performance rubber foam. Vulcanization characteristics can be measured by vulcanization rheometer, but there isn't any convenient measuring method for foaming characteristics. Nowadays a number of moving die rheometers have been quipped with a pressure sensor which could record pressure curve while measuring the vulcanization characteristic of rubber. This measurement provides a convenient and speedy way of measuring the foam characteristics of rubber. How to use the rheometer equipped with pressure transducer to study the curing-blowing characteristics of foamed rubber was discussed in this paper .The decomposition kinetics of foaming agent H in nature rubber and various factors that influence the vulcanization and foaming are studied using rheometer. Blowing agent is the source of energy for manufacturing foam material. There are three common chemical blowing agents AC, OBSH, H. But all of them have their own shortcomings. In order to increase the volume of gas generated and control foaming speed,Multi-blowing agent are used. When combination of two of the three is used as multi-blowing agent the gas volume generated is lager than the summation of the two used separately, and the speed of blowing is between the two. With this conclusion we can combine blowing agents with different ratios to optimize foaming process, to get desired gas volume and foaming speed thus to meet the demands of a specific application. To prepare high performance and property controllable rubber foam, we need to study...