P. L. Nayak

Chitosan: a New Versatile Bio-polymer for Various Applications

Chitin is the second-most natural polysaccharide in the world, next to cellulose. The main sources of chitin are two marine crustaceans, shrimp and crab. Our objective is to appraise the state of art concerning this polysaccharide, as well as one of its most important derivatives known as chitosan. Chitosan is soluble in acidic aquous media and has vast applications in various fields. Here we briefly describe the characterization, chemical modification, de-polymerization and applications of chitin and chitosan. This review emphasizes recent papers on high value adding applications of these materials in gene therapy, drug delivery, wastewater treatment, packaging, etc.

Nanocomposites from Polycaprolactone (PCL)/Soy Protein Isolate (SPI) Blend with Organoclay

New biobased, ecofriendly nanocomposites were prepared from polycaprolactone (PCL)/soy protein isolate (SPI) blend (80/20 wt/wt) with organically modified clay, by melt compounding. X-ray diffraction and transmission electron microscopy analysis revealed that an intercalated nanocomposite was formed and the silicate layers of the clay were uniformly dispersed at a nanometer scale in matrix polymer. There was great enhancement of both tensile and dynamic mechanical properties in the nanocomposite. A rheological study revealed that the nanocomposite exhibits strong shear-thinning behavior in the melted state, and a percolated network of clay particles was formed in the melted state.

Degradability Studies of Green Nanocomposites Derived From Soy Protein Isolate (Spi)-Furfural Modified with Organoclay

Soy protein isolate has been cross-linked with furfural, a bio-based aldehyde and blended with an organoclay Cloisite 30B. The cross-linking process has been ascertained from FTIR data. The structure and apparent interlayer spacing of the SPI/ MMT nanocomposites prepared via solution intercalation has been detected by X-ray diffraction. The degradation pattern of the cross-linked product has been monitored by TGA method. A computerized LOTUS package method has been used for evaluating the kinetic parameters. The degradation mechanism of the nanocomposites has been discussed in light of the kinetic data. Biodegradability of the nanocomposites has also been reported.

Preparation and Characterization of Edible Films Based on Soy Protein Isolate-Fatty Acid Blends

Edible films containing soy protein isolate, long-chain fatty acids, and cross-linkers using glycerol as the plasticizer have been prepared. FTIR spectra reveal the presence of different groups present in the biofilms. The WVP value is highest in the case of films with 10% oleic acid and decreases with increasing concentration. The thermal degradation pattern and the tensile properties of the films have been discussed. The XRD values indicate that the SPI films remain mostly in the amorphous state. From the SEM picture, it is evident that the fatty acids act as modifier, furfural as the cross-linker, and ZnCl2 as the coordinator.

Polymers from Renewable Resources. XXV. Interpenetrating Polymer Networks Derived from Castor Oil-Isophorone Diisocyanate-Cardanylacrylate/Cardanyl Methacrylate: Thermal and XRD Studies

Abstract A series of interpenetrating polymer networks based on polyurethane of castor oil and isophorone diisocyanate condensed with cardanyl acrylate/cardanyl methacrylate using ethyleneglycol dimethacrylate as a cross-linker and benzoyl peroxide as an initiator were synthesized and characterized. Thermogravimetric analysis was carried out in the light of kinetic parameters using a computerized LOTUS package method. The degree of crystallinity (X cr) was calculated from wide-angle x-ray diffraction analysis.