Regular Film Property Changes of Konjac Glucomannan/Mung Bean Starch Blend Films

Abstract

A series of konjac glucomannan (KGM) and mung bean starch (MBS) blend films with different mixing ratios are prepared, and their microstructure, molecular interactions, and film properties are evaluated. Results indicate that increased KGM content can contribute to the smoother and denser microstructure of the cross section of the KGM/MBS blend films, especially when it is >50%. Fourier transform infrared spectroscopy and X-ray diffraction analysis indicate the existence of molecular interactions among the film components. A mixing ratio of KGM:MBS = 7:3 is suggested to have the optimum mechanical property, but other physical properties such as water contact angle, water vapor permeability (WVP), swelling and solubility, differential scanning calorimetry endothermic peak temperatures, and thermal gravimetric onset temperatures exhibit different change tendencies. These properties could be more impacted by the film's structure and intrinsic molecular properties than the molecular interactions. Moreover, high linearity against component ratio is observed for mechanical properties, water contact angle, swelling and solubility, and WVP, which may offer suggestions for film property predictions. The obtained results may offer suggestions to prepare edible films with desired properties based on KGM and MBS.

Developing a novel konjac flour/poly-vinyl alcohol composite film: Preparation, properties and characterization

“…7 Many chemical components are removed through dry and wet extraction processes to obtain neat KGM. The KGM is composed of β-1,4-linked D-mannosyl and D-glucosyl residues at approximately 1.6:1 or 1.4:1 molar ratio, [8][9][10][11][12][13][14][15] so it is a water-soluble natural polysaccharide. Despite the good film-forming ability, neat KGM films usually have low water resistance properties, which restricts their applications.…”

Water-Mediated Synthesis of Full-Biomass Vitrimer with Enhanced Moldability, Recyclability, and Biodegradability

“…However, its strong hydrophilicity compromises the stability of pure KGM-based films against moisture. Various methods have been employed to improve the water resistance of the films, such as blending KGM with biopolymers − and adding functional fillers. − In addition to its water resistance challenges, KGM also faces limitations in thermo-processing. The abundance of hydrogen bonds in KGM leads to its thermal decomposition before reaching its T g and melting temperature ( T m ).…”