Catalyst system for curing phenolic resole resins
AssigneeBakelite UK Holding Ltd.
InventorsKrishnama Naidu Sompalli, Srinivasan Narashimhan
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Abstract
The present invention relates to a catalyst system which improves the work life of acid-catalyzed resole resins at higher ambient temperatures and provides extended shelf life. The catalyst system comprises an inorganic acid catalyst and one or more polyhydric alcohols. In particular, the present invention relates to a catalyst system wherein the inorganic acid and the alcohol do not convert to an ester when added to the resole resin.
Claims14
A method for curing a resole resin comprising the steps of:
- preparing a catalyst by mixing an inorganic acid, one or more polyhydric alcohols, and 1-4 wt % free morpholine, based on the total weight of the catalyst, that when reacted at a higher ambient temperature do not form an ester, and
- mixing a resole resin with the catalyst, wherein the inorganic acid comprises phosphoric acid and the one or more polyhydric alcohols comprise glycerol and/or glycol and wherein the catalyst is prepared by mixing the phosphoric acid in a range of 20 to 70 wt %, the glycol and/or glycerol up to 50 wt %, and water in a range of 0 to 35 wt %.
An ester-free catalyst system for improving the cure time of acid-catalyzed resole resins at higher ambient temperatures, the catalyst system comprising:
- 20 to 70 wt %, phosphoric acid;
- up to 50 wt %, glycol, glycerol or both;
- up to 35 wt % solvent, and
- 1-4 wt % morpholine, based on a total weight of the catalyst system,
- wherein the catalyst system does not form an ester when reacted at ambient temperatures of 35-45° C.
Dependencies are inferred from the claim text.