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High-resolution 1H nuclear magnetic resonance (1H NMR) was advanced to determine both epoxy value and iodine value (IV) of vegetable oils that occur during their epoxidation. For calibration, rather than using a series of diluted stock samples, epoxidized soybean oils with a range of IV and epoxy value synthesized using entrapped peroxophosphotungstate as the catalyst under different reaction conditions were used. During the epoxidation reaction, IV and epoxy value were tracked with respect to time using 1H NMR and conventional volumetric methods. The integrated peak area of the olefinic hydrogens (5.3–5.5 ppm) was used to calculate the absolute number of double-bonded protons. By comparison of IV obtained by 1H NMR and the traditional Wijs-cyclohexane methods, the correlation coefficient was R2 = 0.9997 for the regression equation y = 1.1314x + 1.0035, where x was the result given by 1H NMR. The average integrated peak areas related to the hydrogens of the epoxide groups located at chemical shifts of 2.9 ppm (monoepoxide) and 3.1 ppm (diepoxide) were used to determine the epoxy value. The quantification of the number of epoxides was carried out by 1H NMR and the values obtained were correlated with epoxide content determined by the hydrochloric acid/acetone method. As a consequence, the correlation coefficient was R2 = 0.9991 for the regression equation y = 0.0052x + 1.7258, where x was the average integrated peak areas related to the hydrogens of the epoxide groups by 1H NMR. The novelty of our study lies in the simultaneous correlation between IV and epoxy value obtained from conventional titrations, the integrated peak area related to olefinic protons, and the average integrated peak area located at the hydrogen of epoxide group, calculated using 1H NMR. This approach is used to monitor and optimize the epoxidation reaction. [ABSTRACT FROM AUTHOR]

A bio‐based plasticizers, acetyl‐oleate triethylene glycol (AOT), was successfully synthesized by using oleic acid as a raw material through esterification, epoxidation, and acetylation. Its structure was analyzed by Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance. The plasticizing performances of this plasticizer was compared with those of two commercial ones: dioctyl terephthalate (DOTP) and dioctyl adipate (DOA). This was done by blending these plasticizers with PVC, respectively. Thermal gravimetric analysis results showed that the 5% weight loss temperature of PVC with AOT was 53°C higher than that of DOA and 36°C higher than that of DOTP. The tensile results showed that the AOT plasticized PVC had excellent stretchability: its elongation at break with 50 phr AOT reached 697.7%. Furthermore, its transmittance was as high as 90%, showing better compatibility of ATO with PVC. [ABSTRACT FROM AUTHOR]