Characterization and properties of sodium alginate from brown algae used as an ecofriendly superabsorbent

International Symposium on Current Progress in Functional Materials

Helmiyati^1 ; Aprilliza, M.^1

Department of Chemistry, Faculty of Mathematics, Natural Sciences Universitas Indonesia, Kampus UI Depok, Depok

16424, Indonesia^1

关键词: Brown algae;    Crystallinity degree;    Decomposition temperature;    FT-IR spectrum;    Intrinsic viscosity;    Mannuronic acids;    Morphological analysis;    Super absorbent;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/188/1/012019/pdf
DOI  :  10.1088/1757-899X/188/1/012019

来源: IOP

【 摘 要 】

Sodium alginate obtained from the extraction of brown algae is used as the backbone for the synthesis of superabsorbent nanocomposite copolymerization. The first stage of extraction is the demineralization process using 0.1 M HCl solution and then 2% Na2CO3solution for 2 hours at 60°C. The rendement of sodium alginate obtained was 44.32% with molecular weight of 40680 g/mol with measurement of the intrinsic viscosity. FTIR spectra of sodium alginate showed mannuronic acid functional group at wavenumber 884 cm-1and the uronic acid at wavenumber 939 cm-1, OH functional group at wavenumber 3200-3400 cm-1, and CH2stretching at wavenumber 2928 cm-1. The diffraction pattern of isolated sodium alginate has specific 2θ at 13.068 and 21.096, amorphous intensity found specific 2θ at 18.058, and the obtained crystallinity degree of the sodium alginate is equal to 29.292% from the XRD analysis. The morphological analysis by SEM shows fibrils of isolated sodium alginate. The success isolation of sodium alginate from brown algae is supported by DSC which shows the decomposition temperature of pure sodium alginate and isolated alginate have close values, namely 251.12°C for pure sodium alginate and 229.90°C for isolated sodium alginate.