A method for removing free formaldehyde in phenolic resin

Abstract

The invention relates to a method for removing free formaldehyde in phenolic resin. The method is to directly pass ozone gas into a certain amount of phenolic resin aqueous solution to oxidize and remove free formaldehyde in the solution. Compared with the prior art, the invention has simple steps, can quickly and efficiently reduce the formaldehyde content in the phenolic resin aqueous solution to 0.2%, and meets relevant national standards. Compared with the prior art, the processing effect is better, more convenient and quicker, and the cost is lower, and it is suitable for large-scale promotion.

Description

technical field

[0001] The invention relates to the technical field of adhesives, in particular to a method for removing free formaldehyde in an aqueous solution of phenolic resin. Background technique

[0002] Phenolic resin is one of the most classic synthetic resins. Due to the easy availability of raw materials, simple production process and equipment, and the product has excellent mechanical properties, it is now widely used in adhesives, wood-based panels, friction materials, refractory materials, etc. field. Phenolic resin is a polymer compound formed by polycondensation of phenolic compounds and aldehyde compounds, among which phenolic resins synthesized by condensation polymerization of phenol and formaldehyde are the most common. However, during the synthesis process, the excessively added formaldehyde raw material cannot react completely, thus remaining in the product and subsequent products, and slowly dissipating into the air, causing harm to people's living en...