| Polyester cord (especially HMLS) as a reinforcing material is widely used in rubber composite, such as tires, belts and hoses for its excellent mechanical strength, modulus of elasticity, dimensional stability and heat resistance. The adhesion of interface has strong effect on comprehensive performance of composite. Because of low active surface of polyester cord, the interface can not be formed the strongly adhesion between polyester cord and rubber. It is necessary to explore new adhesives for enlarging application fields of polyester cord. Traditionally RFL (resorcinol- formaldehyde-latex) adhesive can not make excellent interfacial adhesion. Two-step dipping process is used to improve the interfacial adhesion between polyester cord and rubber in this paper. The interfacial adhesion can be much improved by the choosing composition of first step dipping process, confirming ratio of composition, adjusting the second step composition of RFL adhesive and impregnating technical. Meanwhile the action mechanism of adhesive is discussed in adhesion process, so is the interfacial adhesion in Hi-temperature. The results is token by the following tests, such as H-pull, FT-IR, SEM, OCA 40 Micro Surface Tension Equipment and so on.It is proved that interfacial adhesion between polyester cord and rubber can be enhanced percentage 40～60 by choosing solvable epoxy resin and acid crosslink reagent (PA,SnCl2) as for first step adhesive, and then using RFL adhesive treatment. The composition and technical of first step adhesive is as follows: the ratio between EP and H2O is about 1:8～1:10. Crosslink of EP percentage is among 40% to 60%. And impregnating time is about 90 seconds. In the above condition, the force of H-pull can reach max.. The heat-treat time and temperature is respective confirmed 150 seconds and 130°C for pretreatment of polyester cord.. H-pull force can be increase 3 to 5N/cm by adding TPP and penetrative agents etc.. It is also confirmed that active hydroxyl group and excellent stress strength of adhesive coating is formed when the ratio (mol) between R and F is 1.8～2.0. On the another hand, the proportion (weight) between RF and L within the range of 0.15～0.2 can form good interfacial adhesion between first step coating and second step coating. The heat-treat time and temperature of second step adhesive (RFL) is respective fixed on 120s and 140°C.It is confirmed that two step adhesives are thermodynamic and dynamics wetting by analysis of thermodynamic and dynamics wetting. The action, among epoxy group, terminal hydroxyl, carboxyl group and ester group, can occur by IT-FR Analysis. Simultaneity it can make adhesion action among active hydroxyl group of RF resin, VP latex and epoxy coating. Adhesion strength of polyester cord reinforced rubber composite would be decline with temperature increase in the range 20°C to 150°C, especially apparent descend range 20°C to 100°C. Penetration performance has something to do with crosslink degree of epoxy coating. High viscosity affects sorption equality by SEM Test. Breakage ways can be deduced by surface shape of breakage surface. After two steps impregnating adhesive, the possibility of cohesion breakage can be enhanced by SEM surface shape analysis. Namely the interfacial strength between polyester cord and rubber can be great increase by two-step adhesive.
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