Effect of acetic acid concentration on the acetylation of cassava residue cellulose for Cellulose Diacetate synthesis and eyeglass frame production

Abstract

Onggok, a by-product of tapioca flour production from cassava, contains 23.93 % crude fiber and has potential as a basic material for Cellulose isolation and subsequent Cellulose Diacetate production. This study evaluated the effect of acetic acid concentration during the acetylation process on the quality of Cellulose Diacetate derived from Onggok.The process began with starch hydrolysis and Cellulose isolation from Onggok. Acetylation was carried out using different acetic acid concentrations (90 %, 92.5 %, 95 %, 97.5 %, and 100 %). The resulting Cellulose Diacetate was dissolved in acetone, mixed with a plasticizer, and molded into eyeglass frames under heating conditions. The analyses included Cellulose content determination, characterization of Cellulose Diacetate, and evaluation of eyeglass frame properties.The Cellulose isolated from Onggok contained 91.67 % Cellulose. The acetylation process produced Cellulose Diacetate with acetyl contents ranging from 22.08 % to 46.25 % and degree of substitution values ranging from 1.06 to 3.18. The optimum treatment was obtained using 95 % acetic acid, yielding Cellulose Diacetate with an acetyl content of 40.83 % and a degree of substitution of 2.56. This treatment produced eyeglass frames with a hardness of 155.902 N/cm ² and a dimensional change of 11.67 mm after high-temperature exposure.The use of 95 % acetic acid provides the optimal condition for producing Cellulose Diacetate from Onggok. The results indicate the potential of cassava residue as a sustainable bioresource for Cellulose Diacetate production and eyeglass frame applications.