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In this work, a maleinized soybean oil (SOMA) was melt reacted with polyamide 6 and the thermal, rheological, and morphological properties were evaluated. It was observed that the maleinized soybean oil reacted with polyamide chains, increasing the molecular weight of the polymer. Addition of SOMA also promoted an increase in the amount of α crystalline phase as well as in the crystallinity index. The average amorphous layer thickness (La) was enhanced with the addition of 1 wt % of SOMA, while the average crystalline layer thickness (Lc) were significantly enlarged with the increase in SOMA content, indicating that SOMA structures were located at the interfacial region between amorphous and crystalline. The addition of 5 wt % of SOMA plasticized the PA6, reducing its glass transition temperature. However, the sample containing 5 wt % of SOMA showed an accentuated pseudoplastic behavior as compared to other samples. Addition of SOMA also reduced the tensile strength and increased the elongation at break. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43050.

Ethylene-vinyl acetate copolymer (EVA) was modified by hydrolysis using dielectric heating. The modified EVA was characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis (TG), 1 H Nuclear magnetic resonance (NMR), gel permeation chromatography, and small-angle X-ray scattering. The results showed that the EVA was hydrolyzed with degree between 36.1 and 42.6% according to 1 H NMR and TG results. The relative reaction rate for the sample prepared in the oil bath was 9%/h, while in the dielectric was 150%/h for 15 min. This significant improvement was due to the specific effect of microwave-assisted reactions through dipole rotation and ionic polarization contributions. The hydrolysis reaction promoted a reduction of the pendent group size of EVA backbone. This change directly contributed to increasing melt temperature, crystallization temperature, melt and crystallization enthalpies. Also, decreased the long period, increased the volume crystallinity, and caused reductions amorphous/ crystalline interface and two-phase model deviations.