Red mud reinforced polyvinyl alcohol composite films: synthesis, chemical, mechanical and thermal properties

Abstract

Nowadays biodegradable polymer draws much attention to the researcher compared to the petroleum-based non-biodegradable polymer due to the environmental and energy crisis. Aluminum industry waste red mud (RM) reinforced with polyvinyl alcohol (PVA) organic–inorganic composite film was synthesized by sol–gel method. The effects of sodium lauryl sulfate (SLS) as a compatibilizer on the composite were investigated. The composites were characterized by UV absorption, Fourier transforms infrared spectrophotometer (FTIR), X-ray diffraction, scanning electron microscopy (SEM), EDX. Chemical, mechanical and thermal properties of the composites were investigated with different amount of red mud-PVA and also the comparison between them without and with SLS addition. Physical and chemical bonding in the PVA, PVA-RM, and PVA-RM-SLS were shown through FTIR spectra. SEM images exhibit excellent compatibility between PVA and RM in the composite. Degree of swelling and tensile strength were increased by 71.48% and 194.88% respectively, and again percentage of elongation at break and solubility were decreased by 98.07% and 78.07% respectively for the PVA-RM-SLS composite compared to virgin PVA. TGA thermogram reveals that PVA-RM-SLS system had more thermal stability than pure PVA. All the results showed excellent adhesion between PVA and red mud and established the effect of RM as filler and SLS as compatibilizer. This composite is suitable as packaging materials.