| Popis: |
This report identifies a new approach to process thick molecular composites by non-melt consolidation. The process involves the coagulation of the PBT/Nylon 66 dope from methane sulfonic acid into a block of required dimensions using a specially designed mold. The coagulant diffused into the mold through a porous stainless steel plate while a constant pressure is applied to contain the volume changes during coagulation, thus giving a void-free coagulated block. Further consolidation was carried out in a press. The coagulation process was also accompanied by a study of the diffusion of coagulant into the dope. A power law relationship was established experimentally between the time required for coagulation and thickness of the dope. The experimental results were applied to the new coagulation process described above. Morphology study showed that if large voids are formed during coagulation, phase separated domains of 1-10 micrometer size appeared on the void surface. Other scouting studies using steam as coagulant, multi-layer coatings and spraying dopes as droplets for fast coagulation were also reported. |
