A Kind Of Epoxy Coated Sodium Bicarbonate Preparation And Its Application In Rubber Formulation

This thesis studied a method that use a new kind of microcapsule sodium bicarbonate as foaming agent, produced foam material of SBR and EPDM, and give characterization and analysis to the result.This study with epoxy resin E51 as coating materials, were successfully prepared microcapsule sodium bicarbonate; and then applied it to SBR and EPDM foaming formula, of three different curing agents and the vulcanization of rubber. Finally, foam rubber matching experiment, and carries on the research on the foaming temperature,foaming agent copies and vulcanizing agent a number. Finally, the characterization. we produce microcapsule sodium bicarbonate by methods of epoxy room temperature curing and use it to make foam rubber.1) The microcapsules were prepared by sodium bicarbonate for epoxy curing at room temperature, and characterized. Thermogravimetric analysis(TGA) results show that the micro capsule can effectively improve the decomposition temperature of sodium bicarbonate. And during the proceed of many times coated, we can observe the elevation of decomposition temperature more obviously. with the increasing times of coated, the decomposition temperature of sodium bicarbonate has been orderly elevate to 161.41 ℃, 169.01 ℃, 173.21 ℃ and 173.65 ℃ from154.85 ℃. That is to say, the limitation of coated is three times.2) We adopted new curing way and foaming to make SBR and EPDM foamed, because of the CO2 produced by sodium bicarbonate is too penetrable to stay in rubber, which make it hard to be foaming by traditional moulding foaming ways. Hence we sizing it by moulding and then curing and foaming it in dryer. By this means, we obtained foam rubber which have the lowest apparent density of 0.40 g/cm3 and reached product request of high foaming ratio.(density<0.5g/cm3), Meanwhile,we select three different kinds of peroxide vulcanizing agent(TPB, DCP and BPO) as vulcanizing agent to vulcanize rubber respectively and studied the product. By characterization and analysis, we found that the performance of tensile strength, elongation at break and hardness was the best when using BPO as vulcanizing agent, and we studied portions and curing temperature as well. The experimental results show that new foaming agent of microcapsule sodium bicarbonate, compared to sodium bicarbonate, have a higher decomposition temperature, thus it would be efficiency when it act as foaming agent. 8 portions of bicarbonate and 3of BPO for 100 portions of SBR, The apparent density can be the lowest of 0.400 g/cm3 in 120 ℃. And 8 portions of bicarbonate and 3 of BPO for100 portions of EPDM, The apparent density can be the lowest of 0.395 g/cm3 in 130 ℃.