Research Of NBR Foaming Coatings

In this paper, the experimental basic recipe was composed of NBR rubber as the matrix plastic, high abrasion furnace black N330 as reinforcing filler, azodicarbonamide AC as blowing agent, RD as antioxidant and DOP as plasticizer.NBR foaming coating was prepared by milling methods, which then was coated through free foam process to produce NBR rubber foaming coating openings and closures pore structure can be applied to the coating structure through the adjustment of process and formula.The foaming coating can be widely used in sealing, vibration, acoustic noise and other occasions, which owed to its features such as uniform cell structure, excellent mechanical properties, low cost, easy to mass production, etc.The process made up for the deficiency of the traditional craft foaming rubber to some extent, and broadened the range of applications of rubber foam material.First, the study identified the optimum process conditions.Preliminary single factor experiments were performed to determine the orthogonal experimental program, and thus experiments were conducted for the different segments of the heating temperature and time all these five factors.The weighted analysis of a comprehensive mechanical properties and oil and solvent resistance were conducted to obtain the optimal process condition 1.The weighted analysis of cell structure, expansion ratios were performed to obtain the optimal process condition 2.0n the basis of the process condition 2, the single factor experiments based on the main factors through second period of curing temperature was further applied to determine the final selected process conditions as 15phr blowing agent, first 130℃/30min, Sec 160℃/40min.Then, the study identified the foaming system.By comparative analysis of DTA and foaming effect of different foaming agents, the optimal conditions were established:foaming agent AC 9phr.Thirdly, the study identified the vulcanization system.The results of orthogonal experiment of S/DCP/CBS/MBTS showed that when the vulcanizing system was S/DCP/CBS=1/2/1.5/0.5, the products had the best comprehensive function.On this basis, the foaming coating had closed-cell structure since the vulcanizing system was S/DCP/CBS/PZ through the single factor experiment of accelerator.Fourth, the study identified the filled system.Different types of packing single factor experiments were conducted to study the effect of different fillers on the coated foam, and ultimately the optimal filler was determined as carbon black N330; While using gas silica, its foaming effect and performance was slightly inferior to carbon black N330.Through single factor experiments, the optimal number of copies of carbon black N330 was determined as 30phr.Fifth, the study identified the protection and softening system.The influence of protection system and softening system on foaming effect and properties was studied through the single factor experiment of different antioxidants and plasticizers contents.The optimal protection system was determined as RD 3phr, and the optimal softening system was determined as DOP 15phr, so as to determine the preparation recipe of NBR foaming coating.Finally, this paper studied the applications of foaming coating.The NBR foaming coatings applied to sound-absorbing materials were discussed in this paper by testing and modeling of NBR foaming coatings with closed-cell and open-cell structure.