The detonation synthesis products (nano diamond powder, black powder and gray powder) before and after purification were used to modify fluororubber and nitrile rubber. Studies have shown that although detonation black powder can increase the hardness of rubber, its tensile strength and elongation at break will decrease. When nano diamond powder is added into fluororubber, the comprehensive performance index of the rubber is improved. This is because nano-diamond powder contains functional groups such as light, carboxyl, and methyl groups, which enhance the activity of bonding with polymers, thereby improving the tensile properties, hardness, wear resistance and other performance indicators of rubber.
Research by Russian scholars shows that the wear resistance of fluorine film increases by 100% after adding nano-diamond powder. After adding nano-diamond powder to the polyisoprene rubber used in tires, the wear resistance, elongation, and slowing down of the aging process are improved by 1.3 to 1.7 times, the high-temperature tear resistance is significantly improved, and the tire burst strength is increased from 53 MPa to 154 MPa. Filling silicone rubber with black powder can increase the breaking strength from 53MPa to 154MPa when the absolute length increases by about three times, and the comprehensive elastic strength increases by 3 to 5 times. The critical and maximum elastic modulus corresponds to a black powder content of about 0.6% (weight); filling black powder in the fluororubber component can increase the abrasion resistance by 1.5 to 2 times, which is similar to that of polyisoprene rubber.
Currently, most studies focus on using nano-diamond powder or black powder as fillers to fill rubber or plastic products with stronger functionality, and all of them are low-filling, with the addition amount generally being less than 1%. In the rubber processing process, using nano-diamond powder and black powder to replace 1-3% (weight percentage) of traditional carbon fillers with the same weight can extend the service life (mileage) of non-polar isoprene rubber automobile tires by 30%, while the life of rubber workpieces such as bushings can be increased by 30-100%. At the same time, since the addition of nano-diamond powder reduces the porosity, the power required for mixing is reduced by 5-7%, and it can reduce the generation of bubbles, debris and adhesion on the surface, making demolding easier.
