Poly(vinylidene fluoride) (PVDF)/nanoclay composites were prepared using melt compounding. The effect of acrylic rubber (ACM) as a compatibilizer on different polymorph formation and on the ferroelectric properties of nanocomposites were investigated. The intercalation and morphological structure of the samples were studied using X-ray diffraction (XRD) and transmission electron microscopy (TEM). The infrared spectroscopy and X-ray analysis revealed the coexistence of beta and gamma crystalline forms in PVDF-clay nanocomposite, while in partially miscible PVDF/ACM/clay hybrids, three polymorphs of alpha, beta and g coexisted. The coefficients of electric field-polarization (E-P) Taylor expansion were calculated based on the Lorentz theory. Using a genetic algorithm, complex dielectric susceptibilities as well as the dielectric constants for each sample were calculated and optimized. The predicted dielectric constants were found to be in good agreement with the experimental results. A dielectric constant of 16 (10 Hz) was obtained for PVDF/ACM/ clay (90/10/5), which was 40% higher than that of the PVDF-clay (100/5) nanocomposite without ACM. The improved dielectric performance of the nanocomposites can be attributed to the compatibilizing effect of ACM, which facilitated the growth of b polymorph in the sample. Poly(vinylidene fluoride) (PVDF)/nanoclay composites were prepared using melt compounding. Effect of acrylic rubber(ACM) as a compatibilizer on different polymorph formation and ferroelectric properties of nanocomposites were investigated. Intercalation and morphological structure of the samples were studied using X-ray diffraction (XRD) and transition electron microscopy (TEM). Infrared spectroscopy and X-ray analysis revealed the coexistence of β and γ crystalline forms in PVDF/Clay nanocomposite while in partially miscible PVDF/ACM/Clay hybrids three polymorphs of α, β and γ coexisted. Inclusion of ACM found to improve the ferroelectric properties of PVDF/Clay nanocomposites which is mainly due to the growth of β polymorph in the sample. Coefficients of Electric field-Polarization (E-P) Taylor expansion were calculated based on free energy function according to Landau-Devonshire theory. Using genetic algorithm, complex dielectric susceptibilities as well as dielectric constant for each sample were calculated and optimized. Predicted electric displacement was found to be in quite good agreement with experimental results.

Immiscible and miscible blends of poly(vinylidene fluoride) (PVDF) and acrylic rubber (ACM) were subjected to dynamic vulcanization to investigate the effect of crosslinking on phase separation. As a result of different processability, mixing torque behavior of miscible and immiscible blends was significantly different from one another. Scanning electron microscopy (SEM) was used to investigate the morphology of the system. After dynamic vulcanization, submicron ACM droplets were observed in the samples near the binodal curve of the system under mixing conditions. Small angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC) analysis were used to investigate the effect of dynamic vulcanization on the lamellar structure of the system. It was shown that for samples near the boundary of phase separation, increasing the crosslink density led to a decrease in the lamellar long period (L) as a sign of increment of crosslink density induced phase decomposition. Effects of shear rate on the final morphology of the system were investigated by changing the mixing temperature and by comparing the results of dynamic vulcanization at one phase and two phase regions.

Biodiesel is considered an alternative replacement for petroleum diesel, and enzymatic reaction is one method for biodiesel production. Understanding the kinetics of this reaction is important to achieve higher production rates. The kinetics of transesterification of castor oil using Novozym 435 was investigated in this study. The genetic algorithm was employed for estimation of kinetic parameters including Vmax, KmTG, and KmA in the Ping Pong kinetic model at different temperatures. In most enzymatic reactions that follow the Ping Pong mechanism, inhibition by alcohol has been taken into consideration. Here, we examined a competitive inhibition mechanism and found no inhibition effect at high alcohol‐to‐oil molar ratios of 12.6, 15.6, and 18.9 mol/mol. Arrhenius expressions were used to fit the kinetic parameters for reaction temperatures of 30–50 °C. An acceptable agreement with experimental data at 45 °C was observed when biodiesel yields were predicted using the temperature‐dependent parameters, thus validating the proposed model.