Development and mechanism characterization of high performance soy-based bio-adhesives

Effect of Enzymatic Pretreatment on the Preparation and Properties of Soy-Based Adhesive for Plywood

“…SBA was prepared according to our previous work (Lin et al 2012;Chen et al 2014) with minor modifications. Forty grams of DSF was dissolved in 160 mL of distilled water in a three-necked flask and stirred for 40 min in a 35 °C water bath.…”

“…A comparison of the spectra of DSF and enzyme-treated DSF shows that the shape and strength of X-ray diffraction peaks did not change at angles 2θ of 22.0°, implying that structure of soy protein in DSF was not hydrolyzed during the hydrolysis process of polysaccharides because of the catalytic selectivity of the enzyme. A comparison of the spectra of enzyme-treated DSF and SBA shows that the shape and strength of X-ray diffraction peaks decreased at angles 2θ of 22.0°, indicating that the ordered structure of soy protein decreased after treatment with a combination of acid, salt and alkali, as a result of the acid-and salt-catalyzed hydrolysis of soy protein (Réat et al 2000;Lin et al 2012). The results also indicate that there are more activated functional groups (e.g., -NH2, -COOH, -OH) in SBA than in the enzyme-treated DSF, which may be the main cause of the enhanced water resistance of the cured SBA.…”

“…Recently, petro-based adhesives (e.g., phenolic resins) have been widely used. However, most of them are non-biodegradable and generate carcinogenic gases (e.g., formaldehyde) when used, and this has led to serious environmental pollution and caused damage to the health of workers and consumers (Lin et al 2012;Rahman et al 2014). Biomass-based adhesives derived from natural sustainable resources have attracted much attention in recent years and are considered potential substitutes for existing petro-based adhesives because of their low cost, easy availability from renewable resources, and significant environmental benefits, etc.…”

“…However, applications of SBAs are significantly restricted because of their poor water resistance. Many attempts, such as physical (Sun and Bian 1999;Apichartsrangkoon 2003;Zhang et al 2012) and chemical (Li et al 2004;Gao et al 2012;Lin et al 2012;Zhang et al 2014b) treatment processes, have been made to modify DSF soy protein to improve the water resistance of SBAs, and positive results have been obtained. Improved water resistance has also been observed in SBAs prepared from enzymatically treated soy protein.…”

Comparison of the Adhesive Performances of Soy Meal, Water Washed Meal Fractions, and Protein Isolates

“…SPI is obtained from defatted soy meal or flour, but is about 10 times more expensive than soy meal (Frihart et al, 2013). For this reason, soy meal and soy flour have also been tested as candidates for wood adhesive use (Frihart and Lorenz, 2013;Gao et al, 2011;Lin et al, 2012;Xu et al, 2014). For better and economical use of different soy products, Lorenz et al (2015) compared the wood adhesive performance of a variety of commercial soy flours, protein concentrates and isolates.…”