Photo-chemically induced polycondensation of a pure phenolic resin for additive manufacturing

Bakelite© or phenoplasts are considered the first synthetic polymers in the world. These resins, produced by polycondensation, have always been known for their chemical resistance, excellent flame resistance and thermal...

Insights on the Formation Mechanism of Ultra-Low Friction of Phenolic Resin Graphite at High Temperature

In the present paper, the influences of high temperature on the tribological properties of phenolic resin graphite (PRG) sliding against tungsten carbide-nickel (WC-Ni) alloy in ambient air were investigated systematically. Results demonstrated that the antifriction behaviors of PRG was sensitive to high temperature and PRG exhibits ultra-low coefficient of friction (CoF) of about 0.01–0.015. The low CoF is attributed to the formation of graphite tribofilms, which shows different formation processes on the contact interface at different temperatures (room temperature, 200, 300 and 400 °C). These findings provide insight into the formation mechanism of graphite tribofilms, and provide an important basis for improving the tribological properties of graphite-based friction materials and manufacturing new graphite for seal applications.

Effect of Reinforcement Fiber Arrangement on Thermal and Mechanical Properties of High Silica/Phenolic Resin Insulation Layer

The failure of the high silica/phenolic resin insulation layer under extreme thermal conditions has become an important reason for the trouble of solid rocket motors. A great number of studies have shown that the arrangement of reinforcement fibers is a significant factor in the failure of fiber-reinforced plastic. In this paper, the thermal and mechanical properties of the high silica/phenolic resin insulation layer with different arrangements were analyzed, and the causal relationship between the failure of the insulation layer and the arrangement of reinforcement fibers was given. Two types of heat-insulating layers with strong arrangement and weak arrangement were designed. After the SRM firing test, it is concluded that the essential reason for the failure of the insulation layer is the strength anisotropy caused by the weak arrangement of reinforcement fibers. Besides, the reinforcement fibers of strong arrangement are distributed in all directions, which compensates for the axial strength defects of the weakly arranged insulation layer.