Formaldehyde → Phenol-resorcinol-formaldehyde resins

Participants

Reaction Steps

A resorcinol-phenol-formaldehyde gluing system was prepared according to conventional technology by stirring 100 pans by weight of a resorcinol-phenol mixture and 20 parts by weight of an aqueous formaldehyde solution containing 40 percent by weight of formaldehyde. After said stirring the glue was applied to a surface in an amount of 400 g m2. The formaldehyde (HCHO) concentration above said surface was analysed by sucking air through a filter impregnated with dinitrophenylhydrazine, leaching the filter with acetonirile, and then analysing the extract, by means of HPLC, with regard to the content of HCHO. The volume of analysed air was 28.42 liters, which passed the filter with a flow of 0.98 liters/minute. The results of the analysis are set forth in the Table below.

Provenance & Evidence