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The effects of 60 organic solvent on poly(lactic acid) (PLA) were systematically investigated using the Hansen solubility parameter (HSP). The hydrogen bonding solubility parameter accurately reflects the solubility of PLA films using HSP but it depends on hydrogen bonding, as well as dispersion and polar parameters. The PLA films immersed in organic solvent became cloudy and showed no changes in chemical structure. However, solvent‐induced crystallization of the PLA films was observed. Crystalline structures do not dependent on the organic solvent but on the degree of swelling. The organic solvent‐induced crystallization formed a crystallized mixture of a‐ and β‐forms. The density of the crystalline PLA films was lower than that of amorphous PLA films. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A series of chemically functionalized porous aromatic frameworks (PAFs) have been synthesized and deployed within mixed matrix membranes for gas separation. This series of PAFs delivered for the first time simultaneous control of selective gas transport and physical aging within the membranes. New composites including native and metallated fullerenes were also prepared, and exhibited exceptional increases in their porosity, which in turn resulted in ultrafast gas transport. CO 2 permeability following PAF-1-Li 6 C 60 infusion within poly-(trimethylsilylpropyne) (PTMSP) was as high as 50,600 Barrer, a 70 % improvement. Remarkably, just 9 % of this permeation rate diminished after one year of physical aging, compared to 74 % in the native polymer. A series of characterization techniques revealed this phenomenon to be due to intercalation of polymer chains within the PAF pores, the strength of which being controlled by the levels of chemical functionalization and porosity. The membranes were exploited for gas separations, in particular the stripping of CO 2 from natural gas.

Novel organic solvent-free bio-based epoxy resin for coating was prepared from cashew nut shell liquid which is one of renewable resources. The epoxy coating was fabricated by the reaction between amine compounds and epoxy cardanol prepolymer (ECP). The drying, physical, and thermal properties of the epoxy were investigated and compared with those of the commercial cashew coating. The ECP was synthesized by thermal polymerization under the various conditions. Based on the FT-IR analysis, hydroxyl and carbonyl groups were generated, and viscosity increased with increasing heating temperature and time. On the other hand, the NMR analysis showed decrease in the degree of unsaturation in the side group of cardanol. Based on these results, the polymerization of the ECP could be autoxidized in the unsaturated group in the side chains. The drying time until harden dry of the ECP coating took about 2.5 h at room temperature, which is faster than that of the commercial cashew coating. This is because that the curing of ECP coating was based on the prepolymer (i.e., high molecular weight) and crosslink reaction between epoxy and amine groups. The ECP coating was rubbery state due to the flexible side chains of cardanol. Furthermore, the ECP coating improved chemical stability compared with the commercial cashew.

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