| The chlorinated polyethylene / ethylene propylene diene monomer (CM/EPDM) blend was studied. The effect of blending components, curing system, filler, plasticization agent and anti-aging agent on the properties of CM/EPDM blends were studied in detail by means of Rubber Processing Analyzer (RPA2000), Differential Scanning Calorimeter (DSC), Thermal Gravimetric Analyzer (TG) and Dynamic Mechanical Analyzer (DMA). On this basis, the CM/EPDM foaming system was also studied, and mainly studied the effect of curing-foaming system, filler, and plasticizer and process conditions on the properties of CM/EPDM foam materials, as well as the structure of foam material with the help of Scanning Electron Microscope (SEM).As for the CM/EPDM blend, it was indicated that the combination of CM and EPDM had good compatibility by means of DSC and DMA test, better processing forming by improving the high Mooney viscosity of CM rubber and easy roll release of EPDM rubber when mixing. The heat stability had also been improved according to TG analysis. When the CM/EPDM ratio was 80/20~60/40, the vulcanizated rubber had good mechanical properties and better thermal oxidative aging property. S could significantly increase the tear strength of CM/EPDM vulcanizates, when DCP content was 1.5~2phr, TAIC content was 1~1.5 phr, S content was 0.1~0.2phr, the vulcanizates had the best overall properties. The complex curing system of DCP/S could make the CM/EPDM vulcanizates gain better mechanical properties and thermal oxidative aging property. The mechanical properties of CM/EPDM blend was increased with 40phr CB addition. And the good plasticized result could be obtained with addition of dioctyl phthalate (DOP). The hot air aging property of CM/EPDM vulcanizates was improved with anti-aging agent RD addition, and the better physical property retention of vulcanizates was obtained when the RD content of 1~1.5phr. As for CM/EPDM foaming materials, it was showed that the resulted materials of CM6135 with lower viscosity had the top foaming ratio and the minimal density. The vulcanization rate and decomposition rate of blowing agent azodicarbonamide (AC) matched better as the CM/EPDM ratio equals 70/30, and the resulted vulcanizates had higher foaming ratio and the minimal density. When DCP content was 2phr, the vulcanization rate and decomposition rate of AC matched better, the resulted CM/EPDM materials had uniformity and meticulous cell, smooth surface as well as optimum overall property. With the help of DSC analysis, it was found that the temperature of AC decomposition was around 170℃and the peak decomposition temperature was 229℃. And the temperature of AC decomposition decreased with addition of the blowing agent assistance. Form the SEM photo, the resulted foam materials had uniform cells with large aperture and thin wall by adding blowing agent assistance ZnO. Through the DSC analysis, the CM/EPDM compounds with different AC/ZnO ratios had the similar decomposition behavior. The foam products with lower density and good properties can be obtained when the amount of the AC content was 8~12phr, ZnO content was 6~8phr. Among the studied fillings of calcium carbonate (CaCO3), nano-calcium carbonate (nano-CaCO3) and silica (SiO2), it was found that the resulted CM/EPDM blends containing CaCO3 and nano-CaCO3 had good characteristics with uniform cells and better properties. The vulcanization rate and decomposition rate of blowing agent matched better for the blend with 20~30phr CaCO3 and 20phr DOP, and the resulted foam materials had lower density, higher foaming ratio as well as optimum overall property. By changing the foaming process, it was found that a foam material with smooth surface as well as better physical and mechanical properties could be prepared in the terms of the foam time of 1.5tc90, the temperature of 170℃, the quality of filling 70g.
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