Preparation and Characterization of Blend Film Based on Psyllium Seed Mucilage and Polyvinyl Alcohol as a New Eco-Friendly Packaging Material

Abstract

Psyllium seed mucilage (PSM) is a less-explored natural biopolymer that has the potential for use in producing edible films. In this study, we investigated the development of blend films comprising PSM and polyvinyl alcohol (PVA) to overcome the poor properties of PSM film, which restrict its practical applications. For this purpose, PSM/PVA blend films were fabricated and characterized at different ratios of PSM/PVA (90:10, 70:30, 50:50, 30:70, and 10:90) for the first time. The blend films were smooth, homogeneous, and peeled off smoothly from the plates. The PSM film becomes thicker (0.05–1.36 mm), more water-soluble (25%–70.90%), and permeable to water vapor (23.25–682.46 g mm m⁻²d⁻¹ kPa⁻¹) when mixed with PVA. Adding PVA to the PSM film-forming solution improved the lightness, while the blend films’ redness, yellowness, and biodegradation were decreased. Furthermore, the tensile strength decreased from 27.00 to 5.84 MPa, and the water contact angle decreased from 90.65° to 32.01° with an increasing ratio of PVA. Fourier transform infrared-attenuated total reflectance (FTIR-ATR) results revealed the formation of hydrogen bonds between PSM and PVA. X-ray diffraction (XRD) patterns showed a typical semicrystalline amorphous structure of the blend films. Differential scanning calorimetry (DSC) thermograms revealed that the thermal stability of blend films improved effectively with increasing concentration of PVA. Our findings suggest that PSM/PVA blend films have a huge potential to be used as an alternative to current packaging materials.