Preparation and Characterization of Nanocomposite Films from Chitin Whisker and Waterborne Poly(ester-urethane) With or Without Ultra-Sonification Treatment

Abstract

Two series of nanocomposite films were prepared from waterborne poly(ester-urethane) and chitin whisker with and without ultrasound treatment coded as CW/WPU and CHW/WPU, respectively. The effects of ultra-sonification method and chitin whisker content on the chemical compositions, crystallization behavior and miscibility were studied by attenuated total reflection Fourier transform infrared (ATR-FTIR), wide-angle X-ray diffraction (WXRD), dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM). Thermal stability and mechanical properties of the films were measured by thermogravimetric analysis (TGA) and tensile test, respectively. The results revealed that both nanocomposite films exhibited a certain degree of miscibility when chitin whisker content was lower than 30 wt%, resulting in higher thermal stability and tensile strength than the pure waterborne poly(esterurethane) film. Interestingly, the composite films CW/WPU with ultrasound treatment possessed better miscibility, storage modulus, thermal stability and tensile strength than those without ultrasound treatment over the entire composition range studied here. The difference can be attributed to the relatively higher dispersion level of whisker within poly(ester-urethane) matrix resulting in relatively stronger entanglement and interaction between both components. The ultrasound treatment can effectively improve the miscibility and mechanical properties of the casting nanocomposite films with nano-meter size chitin whisker added. This indicated that the structure, miscibility and mechanical properties of the nanocomposite films depended significantly on the preparation method.

Preparation, properties and applications of polysaccharide nanocrystals in advanced functional nanomaterials: a review

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Natural and Sustainable Superhydrophobic Nanochitin Aerogels for Collecting Methane Bubbles from Underwater

“…Chitin is a major component of the exoskeletons of crustaceans and insects, and it is one of the most representative marine resources. As the second most abundant polysaccharide polymer in nature, , chitin has the advantages of renewability, good biocompatibility, environmental friendliness, and biodegradability. − It has been used as chelating agents, drug carriers, − biofilms, − aerogels, , water treatment additives, biodegradable pressure-sensitive tapes, and wound healing accelerator . Compared with other natural materials, however, the utilization rate of chitin is still low due to its poor solubility.…”

New waterborne polyurethane-based nanocomposites reinforced with low loading levels of chitin whisker

“…[15][16][17]. Chitin whiskers (ChWs), obtained by removing protein and other impurities from chitin, also possess excellent rigidity and intensity and are often used as a reinforcing agent in nanocomposites [18]. They are being widely used in aerospace flight vehicle elements and components, as well as in the chemical industry, machinery, motorcars, biomedicine and other industrial applications.…”