Mechanical Behavior of Degradable Thermoplastic Composites

摘要

Long fiber nylon 6 composites were subjected to hot, wet environments, similar to those existing downhole, for up to two days. The effects of fiber type on moisture absorption and subsequent degradation of mechanical properties were investigated. Specimens with magnesium oxide (MgO) embedded in the matrix were also prepared to study the effect of the MgO additive on moisture absorption and composite degradation. A direct correlation exists between the amount of moisture absorbed by the composites and the reduction in their mechanical properties. The type of fiber, whether glass or carbon, played a significant role in the degradation of mechanical properties with the glass fiber composites experiencing a larger reduction in strength, modulus, and fracture toughness than the carbon fiber composites. The presence of MgO served to enhance moisture absorption in both the glass fiber and carbon fiber composites and increased the degree of mechanical property degradation.