| Grinding process is a very important technique for machining and it is essential for precision finishing and super finishing. So it is widely used in many industries. The characteristics of abrasive tools are closed to the improvement of modern industry. Resin bond super abrasive tools have the merit of low-temperature curing, short-time of producing period, uncomplicated equipment and product procedure. The characteristics of abrasive tools are of high grinding efficiency, self-sharpening, not easy to block up work surface. So the work surface can be processed very well. This kind of abrasive tools have certain elasticity and polish property , mainly used to the precision finishing and polish process for the hard alloy and various materials difficult to process.But the thermal property of phenolics resin commonly used in resin bond abrasive tools is poor comparatively. A lot of heat given out during grinding process can result in resin decomposition ,then abrasive materials would come off before they had been blunt. The grind efficiency of the tools and the work quality can be affected. To improve phenolics thermal property, two ideas about modified phenolics and bismaleimide resin are introduced based on many documents. Two high temperature resistant polymers are synthesized, suitable for resin bond superabrasive tools.First bismaleimide(BMI)/4,4'-diamino diphenyl methane(DDM) oligemor was synthesized, then was carried out in melt at 110120癈 with epoxy . The resultant modified resin BMI/DDM/epoxy was obtained. Three epoxy were used as the BMI/DDM modifier, namely E-44, E-51and F-51.the resultant resin was characterized by FT-IR spectral studies, tensile strength, impact strength and softening point, differential thermal analysis (DTA), thermogravimetry (TG). Comparing FT-IR spectral of the oligemor and the cured BMI/DDM/epoxy modified resin, the reaction between the epoxy and the BMI/DDM oligemor can be confirmed. The charpy impact strength of the BMI/DDM/epoxy resin used F-51 as the modifier was 8.02kJ-m-2, slight lower than E-44 and E-51, which charpy impact strength was 8.76kJ-m-2 and 8.42kJ-m-2 respectively. But heat decomposition temperature of the former was 366? much higher than two latter which heat decomposition temperature were 316? and 320? respectively. TG showed that the temperature of losing half weight on BMI/DDM/epoxy resin modified by F-51 was 450 癈. These indicated modified resin have good thermal properties. The curing process was identified recording to exothermic peak temperature 148-222? of the DTA curve. It indicated that cured temperature was suitable for hot-forming process. The resin softening point with different ratios of BMI, DDM and Epoxy was about 59-65 癈. Tensile strength of modified resin decreased with increase in molar ratio of DDM to BMI and mass ratio of F-51 to BMI/DDM oligomer and impact strength was contrary to that. While the influence of ratio variation ontensile strength was more greater than its on impact strength. Tensile strength of diamond abrasive tools used modified resin as its bond was all over 20MPa and grinding property was superior to unmodified resin bond diamond abrasive tools.Ally] ether phenolic resin(AEF) was synthesized in solution at low temperature from novolak and allyl chloride, then AEF/BMI copolymer was produced in melt. The resultants were characterized by FTIR spectral studies, hydroxyl contents, tensile strength, impact strength and softening point, different thermal analysis, TG . The hydroxyl contents were determined by acetylization method, then ether ratio were obtained by comparing hydroxyl contents of pre-reaction and post-reaction. The ether ratio of AEF was 71.5%, 46.7%and 24.8% with the ratio of phenolics to allyl chloride was 1:1,2:1 and 3:1 respectively while the productivity was 61.4%,79.2% and 82.4% respectively. AEF resin can be dissolved in the non-polar solvent such as toluene and xylene as well as alcohol. FT-IR spectral of the AEF resin can testify allyl group in the resultant. There was a exothermic peak at 165-22...
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