Mechanical Properties and Water Absorption of Alginate/hydroxypropyl Methyl Cellulose Blend Membranes with Semi-interpenetrating Network

Sodium alginate (SA) is a renewable material with broad application prospects in textiles, medicine, and other fields. However, the disadvantage of poor strength and brittleness limited its future application. In this work, the SA was reinforced by the hydroxypropyl methyl cellulose (HPMC) with a semi-interpenetrating network which leverages the favourable properties. The structure and surface morphology of SA/HPMC blend membranes after Ca ion cross-linking were examined by FTIR, Raman, XRD and SEM. The mechanical properties and water absorbency of the blend membranes were also studied. The results indicated that the hydrogen bond was found in SA/HPMC blend membranes, which improved the SA/HPMC blend membranes stability. Compared with calcium alginate membrane, the tensile strength and elongation at break of SA/HPMC blend membranes were improved to 57 % and 400 %, respectively.