Thermal degradation kinetics of polypropylene/clay nanocomposites prepared by injection molding compounder

Abstract

Polypropylene/clay nanocomposites with different nanoparticles are prepared using a specially designed polymer nanocomposite injection molding compounder with a hyperbolic nozzle. The thermal degradation kinetics is studied by estimating the kinetic parameter, activation energy through ASTM E1641 procedure and by the procedures suggested by ICTAC. The activation energies of PP/MMT and PP/OMHT are increasing from 121 and 147 kJ/mol K, respectively, while PP/OMMT and PP/MICA are rather on a linear or a slightly decreasing trend from 160 and 165 kJ/mol K, respectively, over the extent of conversion. The similar trend can be observed in pre-exponential factor between the different nanocomposites. The reaction model curve explains the complexity of the degradation over the extent of conversion for different nanocomposites. The optimum working temperature of the different nanocomposites prepared is estimated from the kinetic parameters obtained. The nanocomposites PP/OMMT and PP/MICA can operate for 20,000 h before losing its efficiency at 211 and 209 C, respectively, whereas, PP/MMT and PP/OMHT can operate at 165 and 198 C, respectively. The influence of the different nanoparticles, their physical and chemical characteristics in the improvement of the thermal stability has been explained.

Polypropylene nanocomposites produced by in‐situ grafting of maleic anhydride using different mixing procedures

“…Specific degradation temperatures ( T d ), at 1%, 2%, 5%, and 10% of weight loss, are shown in Figure 10B. As it can be appreciated, in case of PP these four values fit the expected exponential dependency of initial weight loss with temperature 48 . The same occurs with PPgV.…”

“…As it can be appreciated, in case of PP these four values fit the expected exponential dependency of initial weight loss with temperature. 48 The same occurs with PPgV. The functionalized polymer starts and ends its degradation process before PP, at about 280 and 465 C, respectively.…”

Porous‐structured vermiculite/polybutylene adipate terephthalate composite films: The morphology, mechanical properties, and nonisothermal degradation kinetics

“…The Coats–Redfern equation is usually used to speculate the reaction mechanism. The TG data at different heating rates were calculated by substituting 34 thermal degradation mechanism functions (Table S3), and the optimal thermal degradation mechanism function equations satisfying the conditions |( E K − E c )/ E k | ≤ 0.1 and |(log A c − log Ak )/log Ak | ≤ 0.2 were found by fitting the slopes of the straight lines K and E c and log A c 41 . The optimal mechanism function for the sample to satisfy the above conditions was calculated to be function 23 and the kinetic parameters of thermal degradation are shown in Table 3.…”

Structure–properties‐performance relationships in complex epoxy nanocomposites: A complete picture applying chemorheological and thermo‐mechanical kinetic analyses

“…The presence of SEPA and HSEPA nanoparticles led that polymer chains dissipate more energy and resist against thermal decomposition due to the epoxy denser network as a results of strong chemical interactions of PEI on the surface of nanoparticles with epoxy matrix which proved by increase in E α values. Moreover, the frequency factor Ln ( A ) which is directly proportional to the E α is an indicative of the rate of vibration of the decomposition products 80 . The increment of Ln ( A ) values in the case of EHS, ESEPA, and EHSEPA nanocomposites reveals the fact that these nanoparticles make thermal decomposition reaction harder due to the epoxy denser network as a results of strong chemical interactions of nanoparticles with resin especially in the epoxy system containing PEI functionalized SiO 2 @HNT core‐shell nanoparticles.…”