Study On Adhesion Problem Between Adhesive And Aramid Fiber

Aramid fiber is of the high strength and modulus, excellent dimensional stability, so it's attractive for reinforcement in rubber application. But for its high crystallinity and amorphous region orientation , aramid is lack of functional groups. Therefore, it's difficult to adhere to rubber. And the interface of the aramid reinforce-rubber composite is also very complex. Research of the mechanisms of aramid to rubber bonding was primarily investigated on the interface between adhesion and rubber substrate, while the mechanisms of adhesion and aramid were rare to see. To improving the mechanics, combining the project of Jiangsu Nature Science Funds such as BK2003006 of Research On Aramid Fibers -Rubber Reinforcement's Adhesion Mechanism and Fatigue Properties, the following aspects are studied systematically.1. Research of the relationship between the resorcin-formaldehyde resins(RF) and the pH values of the solution. Under the different conditions of synthetic resin, by using the methods of pH, the RF resins reaction degree can be measured. Results show that the kind of RF resin with the best adhesive property was synthesized under the conditions of the ratio of resorcin to formaldehyde at 1/1.8, the ratio of NaOH to resorcin at 4/100, reaction temperature at 25℃, and reaction time at 6 hours.2. The factors influencing the properties of RFL latex films were investigated, the six factors such as the ratio of resorcin to formaldehyde, the ratio of RF to latex, the components of RFL dipping system, the treatments of RFL forming plain, the RF reaction time and the order of the formaldehyde being put were used to evaluated the properties of RFL latex films. Results show that the ratio of resorcin to formaldehyde, the ratio of RF to latex, the components of RFL dipping system have much effect on both surface and mechanic properties of RFL latex film. And the treatments of RFL forming plain only have a certain effect on the surface properties of the film while the RF reaction time and the order of the formaldehyde being put have effects on the mechanic properties of latex film. Comparing the results, it can be that the kind of RFL latex films with the best property was synthesized under theconditions of the ratio of resorcin to formaldehyde at 1/1.8, the ratio of RF to latex at 18/100, using butadiene-styrene-vinylpyridine latex, the ratio of NaOH to resorcin at 25, reaction temperature at 25°C, and reaction time at 6 hours.3. The mechanisms of dipping system to aramid fiber bonding were investigated. First, the different compounds of dipping system and dipping technology were taken to modify the aramid surface, and then the factor influencing the properties of aramid such as the dipping components was investigated, also comparing the results by using two-step dipping system and three-step dipping system. At last, different samples such as undipped and dipped aramid were investigated by the technology of SEM and ESCA, and then got the results of the aramid surface properties and the contents on the aramid surface. Using the test results, the mechanisms of dipping system to aramid fiber bonding were discussed.