Oxidized pea starch/chitosan composite films: Structural characterization and properties

Abstract

In this article, a series of oxidized pea starch/chitosan (OPS/CS) blend films were prepared by a casting and solvent evaporation method. The structure, thermal behavior, and mechanical properties of the films were investigated by means of Fourier transform infrared spectroscopy, wide-angle X-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and tensile testing. The results suggested that, in addition to hydrogen bonding, the interactions between OPS and CS molecules were enhanced by the formation of electrostatic interaction between the negatively charged carboxyl groups on OPS and the positively charged amino groups on CS. Compared with the pea starch/chitosan (PS/CS) blend films, OPS/CS blend films exhibited significantly higher tensile strength with significantly lower elongation at break. Moreover, incorporation of CS into the OPS matrix also led to a decrease in moisture uptake by the composite film.

Physical and microstructural properties of biodegradable films based on pea starch and PVA

“…Starch films exhibited a homogeneous, smooth appearance and the presence of starch granules was not detected. These results coincide with those obtained by several authors working on pea starch films obtained by means of casting (Chen et al, 2009 andWu et al, 2010). On the contrary, the cross section images presented a heterogeneously-fractured layer near the film surface, which points to the progress of crystallization in this region, probably associated to the greater water molecular mobility near the film surface (Cano et al, 2014).…”

Properties and ageing behaviour of pea starch films as affected by blend with poly(vinyl alcohol)

“…2 and 3 show the FESEM images of the surface and cross section of the different films. S films had a smooth surface and a homogeneous internal structure, typical of gelatinized starch, as was found in other studies (Cano et al, 2014;Chen, Liu, Chang, Cao, & Anderson, 2009;Wu et al, 2010). Nevertheless, the presence of a heterogeneously-fractured layer near the film surface reveals the progress of crystallization in this zone, probably due to the greater molecular mobility associated with the diffusion of water vapour to the film surface (Cano et al, 2014).…”

Influence of plasticizer with different functional groups on thermoplastic starch

“…Absorption of starch occurred similarly as reported in previous work. 8,18 The broad band at 3334 cm 14,16 Finally, bands at 1019-1018 cm 21 were allocated to C-O stretching from C-O-C. 14,16,38 The absorption band at 1019 cm 21 was clearly visible for all plasticized samples, indicating low crystallinity. 39 All spectra showed shifts in the fingerprint region of starch, indicating interaction between starch and additives.…”