Modification of starch using alkali, adipic acid, and mustard oil in search of an improved biomaterial

Abstract

This study aimed to modify starch using a combination of alkali and adipic acid and mustard oil to improve the mechanical and absorbency properties. Acid and oil were applied for uniform and quick swelling and gelatinization of starch, while alkali helped the whole gelatinization process at a lower temperature at a uniform rate. Chain scissoring via oxidation and reformation of bonds within the adjacent chains have resulted in the modified structure of starch. The material underwent several tests, including mechanical, thermal, and absorbency tests. The maximum tensile strength after modification was recorded at 8.58 MPa, while the absorbency reduced to below 60%, which is generally found above 150% in native starch. The thermal properties were found to be the least affected by the modification. Comparison with other modified starches showed considerable success, but the most significant aspect was found to be the low product cost. Comparison with other biopolymers and synthetic polymers also proved some improvements in this study.

Effect of fibre loading on mechanical properties of jute fibre bundle reinforced gypsum composites

“…Here, the modulus decreased till 4% fibre bundle loading, but later, with the addition of fibre, the values increased gradually. Modulus is measured by the ratio of applied stress or force to the change in dimension or strain onto the material [ 22 , 30 ]. If the stress value is lower while keeping the strain constant, which means the material is needing lesser force to be deformed, then the modulus value decreases.…”