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Acid surface modified carbon nanotube (MCNT)-, carbon nanotube (CNT)-filled fluoroelastomer (FE), and unfilled-FE were prepared (MCNT/FE, CNT/FE, and FE). Dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) showed that the glass transition temperature (Tg) of MCNT/FE is less than that of CNT/FE and FE. The storage modulus of CNT/FE is higher than that of MCNT/FE over the whole temperature range. Storage modulus in rubbery state is higher in the case of MCNT/FE when compared to FE, however, in glassy state, it is slightly higher. For MCNT/FE at glassy and rubbery state, loss modulus is less than that of CNT/FE. Loss modulus in rubbery states is higher in the case of MCNT/FE compared to FE and in glassy states for both are the same. The DSC, DMA, and X-ray diffraction (XRD) results confirmed that the FE and filler/FE is partially crystalline mostly in γ-form. MCNT and CNT together with shear and high temperature, induced γ-crystallinity in the FE, γ-phase melting of MCNT/FE is higher than that of CNT/FE and FE. Most probably MCNT/FE obeys behaviors of thin films with high surface energy substrate interactions, while in CNT/FE the substrate surface energy is lower. XRD and DSC showed that MCNT causes more γ-crystallinity in FE compared to others. Tetrafluoroethylene segments crystals have the degree of crystallinity in the order of CNT/FE > MCNT/FE > FE. The γ–phase crystal size is in the order of FE > CNT/FE > MCNT/FE. XRD, DSC, and DMA results for FE and filler/FE confirmed each other. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

A generally applicable stoichiometric and kinetic model was developed for the polymerization of dimer fatty acids with ethylenediamine. The rate equations were second-order before 90% conversion and were used between 405 and 475 K. The parameters of the rate equations were determined with nonlinear regression analysis. A comparison of the model predictions and the experimental data showed that the approach was useful in predicting the polymerization kinetics. The equilibrium constant changed from 3.175 to 7.311. The frequency factor and activation energy for the forward rate constant before 90% conversion were 2,716,894 kg mol−1 min−1 and 66.7 kJ mol−1, respectively. The equilibrium constant was independent of the temperature at frequency factor and activation energy values of 74.4 and 9.7 kJ mol−1, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2504–2513, 2004