摘要 |
Novolak phenolic resin compositions are formed into molding granules by homogenizing the composition above the melting point of the resin, calendering the homogenized composition with conversion into a coherent sheet, rolling the sheet between a pair of rollers, at least one of which is indented, to produce a coherent embossed sheet, fracturating the embossed sheet with separation of the granules having substantially the shape and size of the embossments, coating the granules with a phenolic compound and heat-treating the coated granules by flowing a stream of inert gas having a temperature not exceeding 130 DEG C. The resulting granules are free-flowing, free from a tendency to release dust and particularly suitable for injection molding.
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