Unlike many biopolymers, alpha-1,3-glucan (alpha-1,3-GLU) is water-insoluble, making it a promising candidate for the production of moisture-resistant films with applications in biodegradable packaging, biomedicine, and cosmetics. This study aimed to characterize the structural, physicochemical (water affinity, optical, mechanical), and biodegradation properties of a film made from alpha-1,3-GLU extracted from Laetiporus sulphureus. The film was fabricated through alkaline dissolution, casting, drying, washing to remove residual NaOH, and re-plasticization with a glycerol solution. FTIR and Raman spectroscopy confirmed the polysaccharide nature of the film, with predominant alpha-glycosidic linkages. The film exhibited a semi-crystalline structure and high opacity due to surface roughness resulting from polymer coagulation. Owing to re-plasticization, the film showed a high moisture content (similar to 47%), high water solubility (81.95% after 24 h), and weak mechanical properties (tensile strength = 1.28 MPa, elongation at break approximate to 10%). Its water vapor permeability (53.69 g mm m(-2) d(-1) kPa(-1)) was comparable to other glycerol-plasticized polysaccharide films reported in the literature. The film supported the adhesion of soil microorganisms and target bacteria and was susceptible to degradation by Trichoderma harzianum and endo- and exo-alpha-1,3-glucanases, indicating its biodegradability. The limitations in its mechanical strength and excessive hydration indicate the need for improvements in the composition and methods of producing alpha-1,3-GLU films.

The objective of the present work was to investigate the effect of CMC biopolymer on the physicochemical, mechanical, thermal, barrier, and biodegradation properties of PVA-based films. The polymeric films were developed using solution casting method, incorporating CMC at concentrations ranging from 0.5 to 1.5%. With the addition of CMC, the tensile strength (TS) of the hybrid films was reduced from 1.40 +/- 0.02 MPa to 1.99 +/- 0.02 MPa. However, there was a significant improvement in the elongation at break (EAB) up to 49.29% compared to PVA film. The addition of CMC resulted in substantial improvements in water vapor permeability (WVP) and moisture retention capacity (MRC), showcasing a 38.73% improvement in WVP and a satisfactory MRC of 78.374% at 0.5% CMC concentration. The hybrid films also exhibit enhanced light absorbance at UV wavelength with opacity ranging from 0.301 to 1.413. TGA analysis showed a notable enhancement in the decomposition temperature of the hybrid PVA/CMC films, resulting in reduced mass loss compared to the PVA film. FTIR spectra confirmed that blending CMC with PVA led to the formation of strong hydrogen bonds within the polymer blend, significantly affecting the intermolecular forces inside the cellulose matrix. Moreover, with the addition of CMC, the degradation rate of the PVA/CMC film was increased approximately to 40% on the 30th day of soil burial. The films also exhibit effective microbial degradation against Pseudomonas putida and Bacillus subtilis bacteria strains as compared to commercial plastics. Overall, the obtained results validate the use of CMC biopolymer for blending of single polymer system as well as scaling down the extensive use of petroleum-based polymers in the field of packaging.

The present work investigates the development and characterization of cellulose acetate (CA) films with varying concentrations of CA, incorporating glycerol as a plasticizer and calcium chloride (CaCl2) as a crosslinker. The films were fabricated using solution casting and phase inversion techniques. The inclusion of glycerol significantly enhanced the surface morphology, tensile strength (TS), and elongation at break (EAB) of the films. The optimal composition, containing 10% (w/v) CA and 1% (v/v) glycerol, achieved the highest TS (3.199 +/- 0.077 MPa) and EAB (9.500% +/- 0.401%). The addition of CaCl2 to CA resulted in improved thermal properties of the films, suggesting effective crosslinking between CA and glycerol, as demonstrated by the DSC and TGA analyses. FTIR analysis suggested that glycerol interacts with cellulose, through hydrogen bonding, modifying the intermolecular forces within the cellulose matrix. Glycerol also improved the films' hydrophilicity and reduced swelling, solubility, and water contact angle (WCA). The films also exhibited antimicrobial properties against Staphylococcus aureus (S. aureus), a gram-positive bacterium, and achieved a soil biodegradation rate of 43.65% within 30 days. These results suggest that CA films with optimized glycerol and CaCl2 are promising for various industrial and medical applications where enhanced mechanical properties, permeability control, and biodegradability are essential.