A Study On A New Kind Of Polybenzoxazine Modified Phenolic Resin And The Application On Abrasives

Phenolic resin is the oldest synthetic resin and the products have been applied to a wide area. It has high mechanical properties, insulating property, and shape stability. It is flame retardant and low smoke. And it also works easily. But the phenol hydroxides and methylenes in the resin molecular structure are easily oxidized, and that affects the thermal stability.As a new type of ring opening polymerization phenolic resin, polybenzoxazines have some excellent characteristic such as small shrinkage in curing, molecular design flexibility, good thermal stability. Polybenzoxazines are more than phenolic resin, for example there is no low molecular matters release during the curing process.In this paper, by a curing experiment and the analyse of IR, It is concluded that the cured resin molecular structure has characters of phenolic resin and polybenzoxazines. That proves the reaction of polybenzoxazines and phenolic. And two kinds of polybenzoxazine modified resins by proper process design are also composed. In the process, the molecular weight of the resin is tracked and controlled by GPC. And then TGA and strength test results are both preferable. The decomposable temperature is more than 420℃and the tensile strength is enhanced 34.84% than the normal phenolic resinIn addition, A application experiment in association with a abrasive factory is also finished, the rigidity of the abrasive wheels made from polybenzoxazine modified phenolic resin is enhanced two grade, and the grinding speed is enhanced 6.34%, but the wear is reduced 37.6%。...