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Resois fenolicos; resois espumaveis; compositions of resois process for formation of resois fenolicos; process for formation of resois; resol liquid composition fenolica; cell; and foam fenolica
Resois fenolicos; resois espumaveis; compositions of resois process for formation of resois fenolicos; process for formation of resois; resol liquid composition fenolica; cell; and foam fenolica
Phenolic resoles are provided which are free of ionic species capable of being removed by the free acid form of a cation exchange resin and the free base form of an anion exchange resin. The deionized resoles of the invention have extended shelf-life due to their enhanced inherent stability towards self-condensation under otherwise adverse aging conditions. Notwithstanding their extended shelf-life, the resoles of the invention have excellent reactivity as foamable compositions, and are used with particular advantage for the formation of cellular phenolic resins. Also provided is a method for producing phenolic resoles having the aforementioned characteristics which comprises treatment of alkaline metal catalyzed condensates of a phenol and an aldehyde with cation and anion exchange resins in their respective free acid and free base forms.
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