Influence of the drying route on the depolymerization and properties of chitosan

In this work, a chitosan sample with a high degree of deacetylation (DD >95%) obtained from freshwater shrimp shells was subjected to drying processes in an electric oven and by supercritical CO₂. The results indicated that drying chitosan particles with supercritical CO₂ resulted in a very significant increase in specific surface area and pore volume, and also increased the material's crystallinity index. This drying route led to a more than 10‐fold reduction in viscosimetric molecular weight (from 35.3 to 3.0 kDa), indicating that the physical drying process caused the chitosan to depolymerize, which usually occurs by enzymatic and chemical methods, according to the literature. Low molecular weight chitosan is essential for some applications in the field of biomedicine (drug delivery for example); hence, drying via the CO₂ route can be considered a promising technique for the production of high value‐added materials with applications in this area. POLYM. ENG. SCI., 55:1969–1976, 2015. © 2014 Society of Plastics Engineers     

New insights into the hardening and pitting corrosion mechanisms of thermally aged duplex stainless steel at 475℃:A comparative study between 2205 and 2101 steels

In this study,the relationship between spinodal decomposition and the formation of Ni-rich clusters and G-phase in the ferrite on hardening and pitting corrosio...     

Effects of Ag addition and dendritic scale on the corrosion behavior of the hypoeutectic Al-5wt% Si alloy

Journal of Applied Electrochemistry - The addition of silver in hypoeutectic Al-Si alloys have been demonstrated to have promising mechanical and electrical properties. However, the relationships...