Investigating the possibilities to produce alginate filaments with locally available seaweeds

Abstract

Alginate is a natural polymer, extracted from brown seaweeds. The study was carried out to extract alginate from brown seaweed namely, Sargassum collected from the coast of Hikkaduwa, Sri Lanka. Extraction of alginate was done using an alkaline solution of sodium carbonate. Calcium alginate filaments were produced through wet spinning. Alginate/Clay, Alginate/Sodium Silicate and Alginate/Graphene Oxide blended filaments were prepared by extruding their solution through a syringe having a diameter of 1/8” to a coagulating bath of aqueous calcium chloride. The highest moisture regain for the filaments was obtained when the sodium alginate solution was mixed with graphene oxide. And also, the best values of the tensile strength and elongation at break were obtained when sodium alginate was blended with graphene oxide. The maximum tensile strength and elongation at break obtained by the addition of graphene oxide is 0.56N and 47% respectively. The addition of sodium silicate to alginate produced filaments with the lowest values for both the tensile strength and elongation at break. The addition of clay shows a maximum tensile strength of 0.52N and 27% elongation at break but when the clay content increased filaments show lower tensile strength and higher elongation at break.