| Chlorinated Polyethylene (CPE) has many good properties as a novel elastomer. It shows behaviour between plastics and rubber due to parts of its main chains remain unchlorinated, and its overall property is determined by chlorine content as well as residual crystallinity. As CPE always dehydrochlorinate during processing, the study on the thermal stability of CPE has been widely reported.In this study, the thermal stability of CPE as well as the properties of vulcanized CPE rubber and CPE/NBR blends was investigated. The effects of stabilizer on CPE's thermal stability, the influence of the types of CPE, fillers, and stabilizers, together with the content of filler, magnesium oxide, and vulcanizing agent were studied. The effects of content of compositions, types of filler and blending ratio of CPE/NBR in blends were also discussed.The experiment results showed that stabilizers played an efficient role in improving the thermal stability of CPE. The results of the Congo Red Method proved that when stabilizers used separately, dibasic lead stearate, lead stearate and organotin T137 showed better effect in decreasing the degradation of CPE. While the thermal stability of CPE containing dibasic lead phosphite 1:3 dibasic lead stearate, lead stearate 1:1 barium stearate, and dibutyl tin dilaurate 1:1 dibasic lead phosphite displayed better effects when them used simultaneously. Epoxidized soybean oil showed cooperative effects with dibutyl tin dilaurate in prolonging the dehydrochlorination time of CPE, but not in enhancing the dehydrochlorination temperature. The results of DSC showed that, when stabilizers used separately, dibasic lead phosphite, barium stearate and organotin 395A were the more efficient inhibitors for the dehydrochlorination of CPE, among which the lead salts was the best one. When stabilizers used simultaneously, either pair demonstrated good effect. The results of TGA test showed that compared with nitrogen, the oxygen accelerated dehydrochlorination of CPE, while the stabilizers had more obvious efficiency in oxygen. The FTIR spectrometry of CPE135A and CPE135B revealed that they are low in residual crystallinity. Further DSC test indicated that CPE135A had a more flexible main chain. With the chlorine content increasing, tensile strength and tear strength improved. As the polarity of polymer main chain increasing, the oil and solvent resistance of CPE140 were better than CPE135.The best content of magnesium oxide was from 5 to 10 phr (mass content) for the vulcanized CPE rubber with carbon black. High antifriction carbon black (HAF) was the most valuable filler for CPE to enhance the tensile and tear strength, and semi reinforcing carbon black (SRF) to enhance the elongation at break. The best content of carbon black was from 40 to 60 phr. For the vulcanized CPE rubber withother fillers, the peroxide (DCP) and thiourea (NA-22) were used as vulcanizing agent. The best content of DCP was from 1to 1.5 phr, and TAIC from 2 to 4 phr, NA-22 0.5 phr, plasticiser-DOP 20 phr. Compared with other fillers, the strengthening effect of silica was most efficient. And there was no different could be seen from the SEM photos of vulcanized CPE rubber.When CPE was blended with NBR, the degree of vulcanizing reached the peak in CPE/NBR=30/70 (mass ratio). The tear strength and elongation at break were biggest in CPE/NBR=80/20. The more CPE used, the more permanent set and hardness increased. The best content of DOP was 10 phr for CPE/NBR blends, DCP from 1 to 2 phr, TAIC 2 phr. The blends with fast extruding furnace (FEF) and HAF had a better strengthening and hardness. The blends with SRF had a better elongation at break. When carbon black used simultaneously, the blends with SRF/HAF=30/20 was the best one. When other fillers used, the blends with silica was the best. In addition, the blends with NBR containing high acrylonitrile content had better properties than which with NBR containing low acrylonitrile content. The SEM photos of CPE/NBR blend showed that the phase of CPE and NBR co...
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