Novolak are made under acide conditions, when the formation of methylol compounds is slow, whereas the conversion of methylol compound to diphenylmethanes is rapid. With the molar excess of phenol, methylol group do not accumulate in the reaction mixture and the result molecules are linier giving a permanently fusible resin, a novolak resin.
Novolak is being patented in certain number of recorded US Adhesive patent. Phenolic resin for shell mold, process for producing the same and resin coated sand.
Phenolic thermosetting resin products are some of the most adaptive materials in the marketplace and hundreds of industries benefit from their use. Five generations of product designers worldwide have come to rely on on phenolic resin based materials many times a day.
An acidic catalyst and a molar excess of phenol to formaldehyde are conditions used to make novolac resins.
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