METHOD OF DETERMINING FREE GLYOXAL IN GLYOXAL-CONTAINING UREA FORMALDEHYDE RESINS Russian patent published in 2013 - IPC G01N30/02 

FIELD: chemistry.

SUBSTANCE: method involves obtaining an alcohol solution of glyoxal by mixing a sample of urea formaldehyde resin with ethyl alcohol, holding for 30 minutes with subsequent filtration on a membrane filter with pore size of 0.2 mcm, collecting a sample of the alcohol solution (35.7+1 mcg) and then adding 10.5±1 mcg benzyl alcohol, 2.0 ml ethanol and 80-100 mg o-phenhylenediamine. The sample is then held for 20 minutes and then put into the evaporator of a gas chromatograph using a microsyringe and conducting analysis with speed of the carrier gas stream (nitrogen) of 30 ml/min, hydrogen - 40 ml/min, air - 500 ml/min, temperature of the column oven of 140°C, temperature of the evaporator of 200°C and detector of 150°C, using a chromatographic column with length of 1.6 m, filled with Reoplex-400 sorbent, deposited on a Chromaton N support, with subsequent determination of the area of chromatographic peaks of the benzyl alcohol and quinoxaline, and calculation of content of free glyoxal in the urea formaldehyde resin, with the following ratio of components, wt %: urea formaldehyde resin 45-55; ethanol 55-45.

EFFECT: method for chromatographic determination of glyoxal in order to determine weight content of free glyoxal in glyoxal-containing urea formaldehyde resins.

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