In particular, the simulations explored the effects of the periodic boundary

conditions of the ZSM-22 pores and the SF(6)-SF(6) molecular interactions on the time (t) dependence of the mean square displacement (d) of the SF(6) molecules. The simulation results clearly indicate that, with time, the molecules undergo three types of diffusions in sequence: a projectile diffusion regime with d similar to t(2), a single-file diffusion regime with d similar to t(0.5), and a normal diffusion regime with d similar to t(1). The time for the transition from the single-file diffusion selleck chemicals to the normal diffusion increases with the length of the pores. When the interaction between the SF(6) molecules is sufficiently strong, there exists also a suppressed single-file (SSF) diffusion regime in between the single-file and normal diffusion regimes that is characterized by d similar to t(alpha) with alpha < 0.5. The intermolecule interaction also substantially affects the durations of the single-file diffusion and the SSF diffusion, as well as the time for the transition to the normal diffusion state. A detailed discussion is provided that compares the results from

this work with those from previous simulation and experimental works. (C) 2009 American Institute of Physics. [doi:10.1063/1.3247576]“
“To investigate the effect of interfacial interaction on the crystallization and mechanical properties of polypropylene (PP)/nano-CaCO3 composites, three kinds of compatibilizers [PP grafted with maleic anhydride (PPg-MA), ethylene-octene

copolymer grafted Ipatasertib with MA (POE-g-MA), and ethylene-vinyl acetate copolymer grafted with MA (EVA-g-MA)] with the same polar groups (MA) but different backbones were used as compatibilizers selleck products to obtain various interfacial interactions among nano-CaCO3, compatibilizer, and PP. The results indicated that compatibilizers encapsulated nano-CaCO3 particles, forming a core-shell structure, and two interfaces were obtained in the cornpatibilized composites: interface between PP and compatibilizer and interface between compatibilizer and nano-CaCO3 particles. The crystallization and mechanical properties of PP/nano-CaCO3 composites were dependent on the interfacial interactions of these two interfaces, especially the interfacial interaction between PP and compatibilizer. The good compatibility between PP chain in PP-g-MA and PP matrix improved the dispersion of nano-CaCO3 particles, favored the nucleation effect of nano-CaCO3, increased the tensile strength and modulus, but reduced the ductility and impact strength of composites. The partial compatibility between POE in POE-g-MA and PP matrix had little effect on crystallization and mechanical properties of PP/nano-CaCO3 composites. The poor compatibility between EVA in EVA-g-MA and PP matrix retarded the nucleation effect of nano-CaCO3, and reduced the tensile strength, modulus, and impact strength. (C) 2009 Wiley Periodicals, Inc.