摘要 |
A resinous product has high resistance to flame spread, low heat release, and exhibits a low smoke-developed rating when exposed to flame or to indirect or radiant heat, and is flexible, tough, free of hydraulic cement, and resistant to cracking and embrittlement upon curing. Such a product is the condensation product of resorcinol with or without included phenol, and a minor amount of paraformaldehyde and aqueous formaldehyde solution. The resorcinol starting material of this invention can also suitably be used in the form of a B-stage or partially cured resin of resorcinol-phenol-formaldehyde which is then condensed with the paraformaldehyde and, if necessary, additional formaldehyde. The product is useful as a cast material or as laminated with fiberglass or can contain fillers or the like. A method of making the product and articles is provided.
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