Tannin-resorcinol-aldehyde cold-set wood adhesives with only formaldehyde as hardener
Abstract
Based on standard tannin adhesive formulations, tannin-resorcinol-glyoxal and tannin-resorcinol-glutaraldehyde cold-setting adhesives were prepared for wood glulam in this paper. Only less para-formaldehyde was added as hardener of adhesives. Both of them showed a rival tensile strength with tannin-resorcinol-formaldehyde adhesive. However they exhibited lower wood failure. The proportion of formaldehyde of the two are drastically decreased.