Effect of glutaraldehyde on thermal and mechanical properties of starch and polyvinyl alcohol blends

Abstract

The aim of this study is to analyze the various compositions of polyvinyl alcohol (PVA) and starch (S) blends. The blends have been cross-linked with glutaraldehyde to enhance its properties. The hydroxyl groups of PVA and starch react with glutaraldehyde via formation of acetal bonds hence crosslinking could take place. The cross-linking of glutaraldehyde is observed with the help of various analytical methods such as differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The presence of two highly reactive alpha protons makes glutaraldehyde more reactive and acidic in nature. The higher reactivity of glutaraldehyde, at higher dosages leads to reduction in H-bonding of PVA and starch. The cross-linked blends showed better thermal and mechanical properties. Viscosity, tensile strength, pencil hardness, and ultimate stress were evaluated to estimate the changes due to cross-linking. It was observed that the mechanical properties are directly proportional to the amount of starch as the starch hydroxyl groups are easily accessible for the cross-linking reaction. The cross-linked blend showed better cohesion between its chains, thereby increasing the glass transition temperature. It was reflected in the subsequent increase in tensile strength properties.

Effect of Cellulose Nanocrystals and Lignin Nanoparticles on Mechanical, Antioxidant and Water Vapour Barrier Properties of Glutaraldehyde Crosslinked PVA Films

“…As reported in previous studies [ 26 , 31 ], when PVA systems are loaded with CNC and LNP, a growth in tensile strength and decrease in elongation at break can be observed when compared with neat PVA films. The addition of CNC and cross-linking reaction with GD restricted the polymer motion, with a consequent increase in tensile strength and decrease in elongation at break in PVA-GD and P-2CNC films [ 48 ]. When LNP are added to PVA-2CNC, they may promote the formation of cross-links.…”

Physically Crosslinked Poly (Vinyl Alcohol)/Kappa-Carrageenan Hydrogels: Structure and Applications

“…Supplementary, bending vibrations due to non-bonded water presence δ(O-H) are registered at ~1640 cm −1 . Also, the strong absorptions at ~2932 cm −1 (PVA) and ~2925 cm −1 (CAR) are attributed to C-H stretching [43][44][45][46][47][48][49].…”

Hexaferrocenium tri[hexa(isothiocyanato)iron(III)] trihydroxonium complex as a new DNA intercalator for electrochemical DNA biosensor

“…The intensity band and the percentage of crystallinity decreased after AuNPs and SiNSs were deposited on SPE. But the intensity band and the percentage of crystallinity were slightly increased after treatment with glutaraldehyde (GA) 31 . The intensity band and the percentage of crystallinity continued to decrease with the addition of the porcine DNA probe and the complementary DNA.…”