Soy protein adhesion enhanced by glutaraldehyde crosslink

Abstract

Soy protein has been considered as an alternative to partly replace petroleum-based polymers for adhesive applications. The weakness of protein-based adhesive is poor water resistance, which limits its outdoor applications. The objective of this research was to improve the water resistance of soy protein adhesive by introducing crosslinkage between amino groups of amino acid residue. Laboratory prepared soy protein isolate (SPI) was used in this study. Glutaraldehyde at concentrations of 4, 20, 40, and 80 mM was used as the crosslinking reagent for SPI modification. Adhesive properties of soy protein modified by glutaraldehyde, as well as thermal and morphological properties, were investigated. Crosslinking-induced protein conformation and structure changes through decrease of amino groups and adding of hydrophobic groups, subsequently affect adhesive performance of SPI. At optimum glutaraldehyde concentration (20 mM), dry, wet, and soak strengths of modified SPI increased to 31.5, 115, and 29.7%, respectively, compared with unmodified SPI.

Preparation of Wood Adhesives Based on Soybean Meal Modified with PEGDA as a Crosslinker and Viscosity Reducer

“…"PEGDA-modified soy meal adhesive," BioResources 8(4), 5380-5391. 5384 The apparent viscosity of all the SM adhesives and modified SM adhesives reduced as the shear rate increased, exhibiting shear thinning behavior, which can be expressed by the Herschel-Bulkley model (Wang et al 2007),…”

Morphological and thermal evaluation of soy protein concentrate on graft copolymerization with ethylmethacrylate

“…Soy proteins have been modified using alkali, 13 urea, 14 and guanidine hydrochloride-sodium dodecylsulphate. 15 Crosslinking, 16 acylation, 17 blending with other polymers, 18 and enzymatic modifications 19 are the other methods to modify the soy proteins. Modification of natural polymers like proteins by graft copolymerization is an important method to alter the properties.…”

Synthesis of bio-adhesives from soybean flour and furfural: Relationship between furfural level and sodium hydroxide concentration

“…Proteins can, not only be denatured or hydrolyzed, but can also be crosslinked with different types of molecules such as ketones, aldehydes or alcohols [13][14][15][16][17]. This allows the creation of an even more entangled three-dimensional network.…”