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The main objective of this study was to prepare functional allopurinol (ALP) incorporated biomaterials using mungbean starch, polyvinyl alcohol, melanin (MEL), and plasticizers. Prepared biomaterials were characterized by FE-SEM and FT-IR analysis. Photothermal conversion efficiencies and ALP release properties of biomaterials were evaluated with NIR laser irradiation. When biomaterials were irradiated with the NIR laser, temperatures increase of MEL-added biomaterials were higher than those of MEL-non-added biomaterials. After NIR laser irradiation, ALP release rates of MEL-added biomaterials were 1.62 times faster than those of MEL-non-added biomaterials. In addition, ALP release using an artificial skin was increased by NIR laser irradiation. ALP release from biomaterials followed Fickian diffusion mechanism, while ALP release using an artificial skin followed a non-Fickian diffusion mechanism. Xanthine oxidase inhibitory (%) for MEL-added biomaterials with/without the addition of GL and XL were 47.5%, 61.7%, and 65.1%, respectively.

This paper reports on a method of preparing chitosan-based films to which sulfosuccinic acid (SSA) is added for crosslinking agent with/without UV curing treatment and applications of a coating materials for foods. The physical, thermal, and optical properties of the UV cured chitosan-based films are investigated including their tensile strength (TS), elongation at break (%E), degree of swelling (DS), solubility (S), and water vapor absorption as well as their biodegradability in soil and applicability of the coating on a fruit. We also evaluated the physical properties of the prepared films to which glycerol (GL), xylitol (XL), and sorbitol (SO) are added to be used as plasticizers. The surface and topography of the prepared films are investigated by scanning electronic microscopy (SEM) and atomic force microscopy analysis (AFM). The results indicate that the films UV cured for 20min possess optimal physical and thermal properties compared to that of non-cured films. The mechanical, thermal, and water barrier properties of SO-added film are also found to be superior to other films with added GL and XL. The degree of biodegradability revealed that the films are degraded by about 40-65% after 220days.

Rates of abrasion by a blade scraper are compared and contrasted with those obtained using an abrasive surface (a DIN abrader) for six rubber compounds: carbon black filled and unfilled vulcanizates of NR, SBR and cis-polybutadiene (BR). Results from the DIN abrader were found to be less sensitive to the amount of frictional work, and less discriminating between different compounds, than those obtained with a blade scraper. These differences are attributed to somewhat different mechanics of tearing in the two cases, even when the same fracture criterion is employed. For a blade, the length of the contact line is unchanged as the applied load increases, whereas for an asperity an increase in load causes an increase in length of the contact area, tending to mitigate the effect of the increased load. Approximate relations are developed along these lines to compare the tearing action of many sharp asperities to that of a blade. The results account reasonably well for the observed differences between rates of abrasion in the two cases. It is also pointed out that the rate of abrasion is not a unique function of the amount of frictional work expended.