Study On The Diatomite Surface Organic Modification And Its Application

The paper was aimed at preparing the organic modified diatomite to replace the silica as a filler. Diatomite with coupling agent(KH-550),stearic acid (SSTA), polyethylene glycol(PEG-400), sodium dodecyl sulfate(SDS), hexadecyl trimethyl ammonium bromide(CTAB) and non-ionic surfactant(span80) as kinds of modifier, has been coating in the suspension system. and application and performance of natural rubber composites were studied.By means of scanning electron microscopy (SEM), fourier transform infrared spectroscopy(FT-IR), dynamic mechanical spectrum(DMS) and other means of characterization including contact angle, sedimentation time, apparent viscosity, the activation index and oil absorption, Experimental results show that the effection of span80 is better obvious than others.he results of span80 modified diatomite show that the settling time was 500min, the apparent viscosity was 43mPas, the activation index was80%,and the oil absorption value of 0.45.On the basis of the former'study, including the amount of modifier, modification time, modified temperature, pH value, stirring rate and modification process was determined.Span-80 modified diatomite optimal conditions that the amount of modifier was 3% ,the modified temperature was 60℃,the modification time was 90min, the pH value was 4, the stirring rate was500r/min and using wet modification process.Maximum force, tensile strength, elongation, hardness and storage modulus among unmodified diatomite ,modified diatomite and white carbon black filled into natural rubber has been determined according to the different number of copies as a filler. At the ratio of 40% diatomite, it showed that 1379% and 1362%,11mPa and 12mPa,153N and 150N,54HA and55HA. At the ratio of 60% diatomite, it showed that 1236% and 1206%,9mPa and 10mPa,137N and 135N,60HA and59HA. At the ratio of 80% diatomite, it showed that 1154% and 1179%,7mPa and9.5mPa,120N and 1235N,65HA and66HA. It remained the same to white carbon black.In addition, unmodified and modified diatomite composite rubber storage modulus was study, At the temperature of 40 degrees below zero, it respectively was 5MPa and7MPa. At the temperature of 100 degrees, it respectively was 0.5MPa and 1MP. It expands the scope of storage modulus into the natural rubber composites.