Analytical Techniques for Measurement of Formaldehyde in Nonwoven Binders, 1993 Nonwovens Conference Proceedings

The accurate and unambiguous determination of formaldehyde is an increasingly important issue for manufacturer’s of latex bonded nonwovens as governmental regulations impose new and more stringent emission standards.

Historically, there have been a number of analytical methods used routinely to define the free and bound formaldehyde in externally crosslinkable and self-crosslinkable latex emulsion binders for nonwoven substrates. These include for example: Nash Reagent for wet latex, AATCC Test Method 112-1990 (Sealed Jar) for latex bonded fabric and webs, the Japanese Ministerial Method for bonded fabrics and webs, and the degradative Chromotronic Method for total formaldehyde content in the binder and substrate. A list of the commonly used methods is shown in References 1-4.

Each is valid and useful within the limitations imposed by the inherent detection limits of the test, the sensitivities to interference from non-formaldehyde agents capable of producing “false positives”, the nature of the test substrate, and the robustness of the test to operator error.

In this paper we compare formaldehyde analysis results obtained for typical Rohm and Haas acrylic latex binders by themselves and on nonwoven substrates. The formaldehyde results from both High

Pressure Liquid Chromatography-Nash reagent, and a novel “headspace GC-mass selective detector” have confirmed the low and ultra-low formaldehyde content in these acrylic lances.