Correlation between Physical Properties and Shear Adhesion Strength of Enzymatically Modified Soy Protein‐Based Adhesives

Abstract

This work was to correlate physical properties with adhesion properties of soy protein‐based adhesives. By building such a correlation, the adhesion properties can be predicted by measuring physical properties of soy protein‐based adhesives. In this context, three important physical properties, viscosity, tacky force, and water resistance, were selected to correlate with adhesion strength of enzymatically modified soy protein‐based adhesives (ESP). Response surface methodology, specifically central composite design, was used with three independent variables to prepare ESP: trypsin concentration (X1), incubation time (X2), and glutaraldehyde (GA) concentration (X3). The three physical properties measured were all greatly affected by our three independent variables with significance at the 95 % confidence level. The responses were then correlated with the adhesion properties of ESP. In conclusion, viscosity can be used to predict the dry adhesion strength of ESP based on the coefficient of determination (R2) of 0.8558. In addition, tacky force and water resistance can be used to represent wet adhesion strength of ESP based on R2 of 0.7082 and 0.6930, respectively (P < 0.05). This work preliminarily identified the significant physical properties that can predict the adhesion strength of the ESP system crosslinked with GA, but the results need to be further confirmed by another protein modification system to give a generic conclusion.

3D printed chitosan dressing crosslinked with genipin for potential healing of chronic wounds

“…4 shows Fourier transform infrared spectra of the starting materials and 3D printed scaffolds. The spectra of CH showed three characteristic bands at 3370 cm -1 , 1659 cm -1 and 1575 cm -1 attributed to the -OH stretching vibration which is generally due to water molecules, -NH2 from the amide group I (C=O), and amide group II respectively (Lambert et al, 1987).…”

“…In addition, a slower reaction involving the generation of an amide takes place via a reaction involving the amino group on CH and ester group (by C-11) of GE (Mi et al, 2001). The amide II band observed at 1550 cm -1 , which is characteristic of N-H deformation (Lambert et al, 1987), could be attributed to the formation of secondary amides due to the latter reaction between the ester and hydroxyl groups of GE and the amino groups of CH. Pure PEG showed peaks at 1105, 947, and 817 cm -1 (Bhattarai et al, 2005) but for the CH-GE-PEG 3D printed films, the hydroxyl, amino and amide groups of CH shifted slightly (3370 cm -1 to 3330 cm -1 for hydroxyl, 1659 cm -1 to 1650 cm -1 for amino group and from 1575 cm -1 to 1550 cm -1 for amide group) due to crosslinking while their intensities decreased due to grafting of PEG (Klein et al, 2016).…”

Improvements and limitation of soy protein‐based adhesive: A review

“…The trypsin modified soy protein adhesives also displayed an improvement in water‐resistance compared to unmodified adhesives. This is because trypsin has the ability to degrade soy protein into smaller molecular size and can expose more hydrophobic groups in protein structures to the surface, hence improving the water‐resistance [ 85 ] .…”

Plant Polyphenol‐Inspired Crosslinking Strategy toward High Bonding Strength and Mildew Resistance for Soy Protein Adhesives

“…[10][11][12]13] In order to enhance the performance defects of soy protein adhesives, a series of modification strategies have been used, such as the use of protein denaturation techniques, chemical crosslinking, organic or inorganic blending, and biomimetic design. [14][15][16][17] The formation of a crosslinked network is an effective approach to prepare high-performance soybean protein adhesives. Polyamine-epichlorohydrin (PAE), [18] epoxides, [19,20] and polyisocyanates [21] are common crosslinking modifiers used to construct intrapenetrating or interpenetrating networks with soy protein molecules to form tough crosslinked systems that can efficiently transfer stress and regulate cohesive interactions that improve their adhesion; however, most epoxy crosslinkers are expensive, and directly introducing them into an adhesive system may lead to severe phase separation in the protein system, resulting in poor bonding strength and toughness.…”