Modification Treatment And Properties Research Of Fiber Reinforced Silicon Dioxide Composites

The fiber reinforced quartz composites were modified by gaseous phase grafting method, and then the microcosmic pattern, specific surface area, dielectric properties, mechanic properties, moisture absorption rate and other properties of composites were measured and analyzed. The results indicate that the modification treatment and subsequent heat treatment have little influence on microcosmic pattern and specific surface area of composite, moreover no damage to dielectric properties or mechanic properties of composite occurs. After modification, the range of dielectric loss variation with frequency of composites is decreased significantly from 4. 7 x 10(-3) -6. 8 x 10(-3) to 1. 7 x 10(-3 )-2. 9 x 10(-3), while the tensile strength of composites is increased evidently from 48. 58 MPa to 63. 49 MPa. The optimized processing condition of modification is (T-bp +30 degrees C)/72 h/80%M. The ultimate moisture absorption rate of the composites shows significant decrease from 6. 35% to 0. 32% after the modification, demonstrating the excellent moisture prevention effects of this method.