MICROBIOLOGICALLY INFLUENCED DEGRADATION OF FIBER-REINFORCED POLYMERIC COMPOSITES

Two fiber-reinforced polymer composites were examined for susceptibili ty to microbiologically influenced degradation. Composites, resins, an d fibers were exposed to sulfur/iron-oxidizing, calcareous-depositing, ammonium-producing, hydrogen-producing, and sulfate-reducing bacteria (SRB) in batch culture. Surfaces were uniformly colonized by all phys iological types of bacteria. Epoxy and vinyl ester neat resins, carbon fibers, and epoxy composites were not adversely affected by microbiol ogical species. SRB degraded the organic surfactant on glass fibers an d preferentially colonized fiber-vinyl ester interfaces. Hydrogen-prod ucing bacteria appeared to disrupt bonding between fibers and vinyl es ter resin and to penetrate the resin at the interface.