The Study On The Preparation And Modification Of The Asphalt Resin Composites

Asphalt resin exhibits processing convenience, easy molding, tensile strength and modulus almost equivalent to phenolic resin, very good compatibility with carbon materials and excellent sliding friction properties. The composites with asphalt resin and graphite behave low surface energy, small tribological coefficient and suitable for the conditions of dry friction. Nevertheless, the asphalt resin composites with graphite shows serious abrasion problem, due to its lower hardness and poor heat resistance at high temperature, in the practical application.The purpose of this paper was to improve the hardness and heat resistance of asphalt resin composites and its wear resistance ulteriorly. In the first place, in order to improve the hardness and heat resistance of asphalt resin composites, the process conditions of preparing asphalt resin composites were optimized. Secondly, the effects on the properties of asphalt resin composites caused by different raw materials and cross-linking agents were tested respectively. In the next place, in order to improve the hardness and heat resistance of asphalt resin composites, physical and chemical modifications were studied. Different fillers were added to the composites in the physical modification. In the synthesis of asphalt resin, inorganic acid L and phenol were added as reactants. The properties of asphalt resin composites were studied in the physical and chemical modification. At the last, the application of the microwave in the preparation and modification of asphalt resin composites were preliminarily investigated.The better conditions of the preparation of asphalt resin composites were as follows: the mixed ratio of asphalt resin and graphite was 3:7; the molding pressure was 30MPa, the particle size was 120 mesh or more; the dwell time was 5 minutes; the preheating temperature is 220℃. The asphalt resin composites exhibited the best heat resistance and hardness, when the trioxane as cross-linking agent synthesized asphalt resin. When the temperature was under 300℃, the properties of asphalt resin composites that was deoiled asphalt as the raw material exceeded that with coal tar pitch. When the temperature preponderated over 300℃, the result was reverse. Adding 10% lanthanum oxide or 8% inorganic acid L and 12% phenol could improve the performance of asphalt resin composites to some extent. Adding lanthanum oxide and inorganic acid L had more obvious effect on the asphalt resin composites. The treatment of the microwave could not only shorten the preparation time of asphalt resin composites but also could improve the performance of asphalt resin composites. Through the modifications and microwave treatment, the hardness of the asphalt resin composites prepared in this paper could increase 100% and the mass loss rate of the asphalt resin composites calcinated for ten hours at 350℃could reduce from 12% to 3% or less.