Determination of Formaldehyde/Melamine Molar Ratio in Amino Resins by Near-Infrared Spectroscopy

Abstract

Melamine-urea-formaldehyde (MUF) resin production has increased in the last years motivated by the current concerns about the effects of formaldehyde on human health and to improve the physical properties of wood panels. Thereby, new processes for MUF synthesis have been developed. All such formulations are susceptible to possible operation error, which can significantly influence the characteristics of the final product. It is therefore crucial for industry to determine the formaldehyde/melamine (F/M) molar ratio of the product using near infrared (NIR) spectroscopy.The use of iPLS (interval Partial Least Squares) enabled to recognize the most interesting spectral ranges for analysis (4400-4800 cm-1). Applying this method, it is possible to measure the error in the dosage of raw materials, determining in a more accurate and expedite method the F/M molar ratio in resins.