Study On Adhesion And Microstructure Of Rubber And Steel Cord

Cobalt salts are commonly used as adhesion promoters for rubber-to-metal adhesives,which play an important role in the adhesion of rubber-metal,while the aging of cobalt salts accelerates the aging of the compounds.In order to retain the beneficial effect of the cobalt salt on the adhesion properties of the rubber to the steel cord,it also eliminates the adverse effect of the cobalt salt on the properties of the compound itself.In this paper,cobalt-coated steel wire and natural rubber as the object,in-depth,detailed study of the adhesion between them.Based on the bonding mechanism of rubber and copper-coated steel cord,the bonding mechanism was expanded and the basic model of the bonding process was established.Finally,through the optimization of the formula so that non-cobalt salt compounds and the cobalt-coated steel cord bonding level reached the industrial level.The paper is divided into three parts:1.According to the rubber and steel cord bonding mechanism,by extending the pre-vulcanization time,increase the amount of CuxS,interfacial bonding and increase the thiazole ring to explore the formula,through these four directions to optimize the formula.Extending the pre-vulcanization time included the effect of adding CTP and BR on the adhesive properties of the compound in the base formulation.The effect of increasing the amount of Cux S produced on the adhesive properties of rubber and steel cord was discussed in terms of sulfur species,sulfur dosage and sulfur molecular size.The results showed that 5phr modified sulfur could make the adhesion of cobalt-free compounds to cobalt-coated steel cords meet the requirements.The binding strength of the compound and the steel wire were respectively determined by the amount of silica and the ratio of N330,zinc oxide and sulfur.The experimental results showed that the adhesion of 10 phr silica was the best.The effects of the dosage of TTA,M and DM on the adhesion were studied.The results showed that the addition of three additives improved the adhesion of rubber-steel wire,but the effect was not significant.2.The experimental results show that the modified sulfur has a great contribution to increase the adhesion between rubber and the cobalt-coated steel cord.The results are proved by means of SEM and DSC,and the mechanism of modified sulfur to increase the interface adhesion is proposed.Due to the special molecular structure of the modified sulfur component,the modified sulfur is dispersed uniformly in the compound and the special components can lead to the formation of chemical bonds between the compound and the metal.These two factors are beneficial to the bonding of rubber and steel cords.3.The mechanism and model of N can increase the adhesion of rubber to steel cords were proposed.N reacts with the rubber in the rubber system,and the ion pairs formed by the self-aggregates of N are also beneficial for the adhesion of the compound to the steel wire.The chemical reactions of sulfur and N were confirmed by FTIR and GPC.The results of crosslinking density and RPA test showed that N formed a network structure in the compound.