Using Renewables in Panelboard Resins to Influence Volatile Organic Compound Emissions from Panels

Abstract

Technical lignin and condensed tannins have been combined with soy flour as model of no-added-formaldehyde adhesive binders for veneer wood products to understand their impacts on volatile organic compounds (VOCs) produced during panel manufacture. VOC emissions captured on manufacturing lauan hardwood plywood at 170˚C were dominated by acetaldehyde, hexaldehyde, acetone, and terpenes in both the condensate and gaseous fractions of press emissions. Other aldehydes including formaldehyde, valeraldehyde, and propionaldehyde were produced in relatively lower quantity during panel manufacture. Compared to using soy flour alone, lignin, and tannin reduced the formaldehyde and acetaldehyde contents in press emissions. These reductions in VOCs had a dependency on adhesive resin pH with an alkaline formulation proving to also decrease longer chain aldehydes such as valeraldehyde and hexaldehyde. Chamber testing plywood panels found the composition of VOC emissions initially released from panels to be prominent compounds released in press emissions formed on panel manufacture. Use of soy flour alone as binder produced relatively high acetaldehyde emissions from panels, whereas incorporating lignin and tannin with soy flour as adhesive binders reduced both acetaldehyde and formaldehyde emissions from panelboards post-manufacture.