ALKALINE PHENOLIC RESOLE RESIN COMPOSITIONS AND THEIR USE
An alkaline phenolic resole resin compositions comprising (a) an aqueous basic solution of a phenolic resole resin, (b) and a polyhydric alcohol, and their use in foundry applications.
1 . An alkaline phenolic resole resin composition comprising (a) an aqueous basic solution of a phenolic resole resin, and (b) an effective stabilizing amount of a polyhydric alcohol.
2 . The alkaline phenolic resole resin composition of claim 1 wherein the polyhydric alcohol is selected from the group consisting of sugar alcohols like glycerol, erythritol, arabitol and alcohols like trimethylol ethane, trimethylol propane, pentaerythritol and polyvinyl alcohol, and mixtures thereof.
3 . The alkaline phenolic resole resin composition of claim 2 wherein the amount of polyhydric alcohol used in the alkaline phenolic resole resin composition is from 0.5 to 15 weight percent based upon the weight to the alkaline phenolic resole resin.
4 . The alkaline phenolic resole resin composition of claim 3 wherein the polyhydric alcohol is glycerol.
5 . The alkaline phenolic resole resin composition of claim 4 wherein the amount of polyhydric alcohol used in the alkaline phenolic resole resin composition is from 0.9 to 5 weight percent.
6 . The alkaline phenolic resole resin composition of claim 5 wherein the aqueous basic solution of the phenolic resole resin has (1) a viscosity of less than about 850 centipoises, (2) a solids content of 35 percent by weight to 75 percent by weigh based upon the total weight of the aqueous basic solution, and (3) an equivalent ratio of base to phenol of from 0.2:1.0 to 1.1:1.0, preferably from 0.3:1.0 to 0.95:1.0.
7 . A foundry mix comprising a major amount of an aggregate and an alkaline phenolic resole resin composition of claim 1 , 2 , 3 , 4 , 5 , or 6 .
8 . A no bake process for preparing a foundry shape comprising mixing the foundry mix of claim 7 with a liquid ester co-reactant, inserting the mixture into a pattern, allowing the mixture to cure, and removing the mixture from the pattern.
9 . A cold box process for preparing a foundry shape comprising blowing the foundry mix of claim 7 into a pattern, contacting the foundry mix with the vapor of a volatile ester co-reactant or carbon dioxide.
10 . A process for casting a metal part comprising fabricating a casting assembly comprising one or more foundry shapes prepared in accordance with claim 8 , pouring molten into and around said casting assembly, allowing said low melting metal to cool and solidify, and then separating the molded article from the casting assembly.
11 . A process for casting a metal part comprising fabricating a casting assembly comprising one or more foundry shapes prepared in accordance with claim 9 , pouring molten into and around said casting assembly, allowing said low melting metal to cool and solidify, and then separating the molded article from the casting assembly.
12 . A process for dissolving the crusted surface of an alkaline phenolic resole resin or the flakes formed when the crusted surface is subjected to mechanical forces comprising:
treating the alkaline phenolic resole resin with an effective stabilizing amount of polyhydric alcohol.
13 . The process of claim 12 wherein the polyhydric alcohol is selected from the group consisting of sugar alcohols like glycerol, erythritol, arabitol and alcohols like trimethylol ethane, trimethylol propane, pentaerythritol and polyvinyl alcohol, and mixtures thereof.
14 . The process of claim 13 wherein the amount of polyhydric alcohol used in the alkaline phenolic resole resin composition is from 0.5 to 15 weight percent based upon the weight to the alkaline phenolic resole resin.
15 . The process of claim 14 wherein the polyhydric alcohol is glycerol.
16 . The process of claim 15 wherein the amount of polyhydric alcohol used in the alkaline phenolic resole resin composition is from 0.9 to 5 weight percent.
17 . The process of claim 16 wherein the aqueous basic solution of the phenolic resole resin has (1) a viscosity of less than about 850 centipoises, (2) a solids content of 35 percent by weight to 75 percent by weight based upon the total weight of the aqueous basic solution, and (3) an equivalent ratio of base to phenol of from 0.2:1.0 to 1.1:1.0, preferably from 0.3:1.0 to 0.95:1.0.