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<正>With decreasing of petroleum resource and increasing environmental concerns,soy-based adhesives will become the leading product of wood industry due to their abundant and renewable predominance.But it has not been widely used because of some disadvantages,mainly the poor water resistance.GPC,DSC and plywood evaluation were employed to characterize the degraded soybean proteins(DSP,treated in the presence of 9wt% sodium hydroxide at 90℃for 2-3.5 hours),the wood adhesives by blending DSP with glyoxal,urea-formaldehyde (UF) resin,melamine-formaldehyde(MF) resin,phenol-formaldehyde(PF) resin and phenol- formaldehyde oligomer.Results indicated that degradation in the presence of strong alkali not only destroyed completely the advanced structures of soy proteins but also resulted in the chain cleavages of the larger-molecular polypeptide,by which obtained a low-viscosity DSP solution suitable for preparing wood adhesive with molecular weight ranged from 282 to 3404.DSC analysis confirmed that the DSP can be crosslinked by glyoxal,UF resin or MF resin,and the curing temperatures of adhesives by blending DSP with PF resin and PF oligomer were from 138 to 182℃.All the wood adhesives prepared using DSP can be used for non-water-resistant applications,but only the DSP-MF blend can be used as water-resistant adhesive.