| 摘要 |
The present invention is directed to compositions and a process leading to colorless or light colored aqueous phicinol-formaldelhyde resoles. Unlike previous technologies, these compositions lead to clear storage stable fast curing, high molecular weight resins. These materials are also capable of producing composite wood panels with superior water absorption and thickness swell test results when soaked in water. The invention essentially consists of an aqueous copolymer of phenol, formaldehyde, and a phenolic carboxylate (e.g. salicylic acid). Methylol phenols are formed under alkaline conditions in the presence of metal chelating agents. These are then condensed into a polymer under alkaline, neutral or acidic conditions. The finished aqueous polymer solution is then acidified to the desired pH using a benzoic acid or a phelnol-carboxylic acid. |
