Glass fiber reinforced thermoplastic cellular plastics
Abstract
Abstract Glass fibers are coated with uncured thermosetting resin selected from the group consisting of glycerol triacrylate, ureaformaldehyde and phenol-formaldehyde of the type designated as B stage. About 5 percent by weight of the coated fibers, while cool, are introduced into a mixture of gas and molten thermoplastic material selected from the group consisting of polypropylene nylon and polystyene shortly (i.e. less than a minute) prior to entry into the mold of low pressure injection molding apparatus. The heat of the molten thermoplastic material brings about a curing of the thermosetting coating on the glass fibers, but such curing is so slow that it becomes effective at about the same time as the thermoplastic material cools and solidifies in the mold. The product, a thermoplastic structural foam having short fibers of thermoset-coated glass fibers distributed throughout, has greater stiffness and greater tensile strength than conventional structural foam.
Inventors
- 👤 W Greenberg
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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