| abstract |
The present invention relates to a method for removing unreacted formaldehyde contained in a resol type phenolic resin, and more particularly, to prepare a methylolphenol precursor and a methylolmelamine precursor by reacting phenols, formaldehyde and melamine under an alkali catalyst. After the polycondensation, a resol-modified phenol-melamine resin is used to easily remove unreacted formaldehyde, have high thermal stability of the produced resin itself, and have excellent flame retardancy, which is used as a heat insulating material, an industrial material, and a building material. The present invention relates to a method for removing unreacted formaldehyde contained in a possible resol type phenol resin.n n n n Removal of methylol phenol precursor, methylol melamine precursor, resol type phenol resin, formaldehyde |