N. Sultana, S. Pawar and U. Sundararaj, "Effect of Processing Techniques on EMI SE of Immiscible PS/PMMA Blends Containing MWCNT: Enhanced Intertube and Interphase Scattering", Industrial & Engineering Chemistry Research, https://doi.org/10.1021/acs.iecr.8b05957 (2019).
In this research, we achieve increased electromagnetic interference shielding effectiveness (EMI SE) in polymer blend nanocomposites through multiple scattering (selective localization-assisted interphase and better dispersion-aided intertube scattering), unlike traditional metal shields, which mostly depend on reflection. We also study the effect of processing techniques on EMI SE of immiscible Polystyrene (PS)/poly(methyl methacrylate) (PMMA)/multiwalled carbon nanotube (MWCNT) systems. The PS/PMMA(80:20) blend nanocomposite with 2.7 vol % MWCNT shows 30 dB EMI SE.
Ehsan Aliabadian, Soheil Sadeghi, Milad Kamkar, Zhangxin Chen, Uttandaraman Sundararaj, "Rheology of fumed silica nanoparticles/partially hydrolyzed polyacrylamide aqueous solutions under small and large amplitude oscillatory shear deformations", Journal of Rheology, https://doi.org/10.1122/1.5024384 (2018)
Partially hydrolyzed polyacrylamide (HPAM) is one of the most widely used polymers for enhanced oil recovery operations. However, high temperature and high salinity in oil reservoirs restrict its functionality and performance. To alleviate this, incorporating fumed silica nanoparticles (NPs) in HPAM solutions was found to be very effective in harsh oil reservoir conditions to improve the efficiency of polymer flooding. Studying the flow behavior of hybrid polymer and fumed silica NP solutions under real reservoir conditions can be very challenging and hard to achieve due to continuously converging and diverging flow through porous structures. In this regard, rheological analysis of such systems under well-controlled flow histories within the capability of rotational rheometers can be of great importance to fully understand the mechanical response of these hybrid solution systems.
Ehsan Aliabadian, Milad Kamkar, Zhangxin Chen, Uttandaraman Sundararaj, "Prevention of network destruction of partially hydrolyzed polyacrylamide (HPAM): Effects of salt, temperature, and fumed silica nanoparticles" Physics of Fluids, https://doi.org/10.1063/1.5080100
Polymer flooding is one of the most effective enhanced oil recovery (EOR) methods. High temperature and a high salt content in oil reservoirs significantly decrease the performance of polymer flooding. In this work, the viscoelastic properties of a partially hydrolyzed polyacrylamide (HPAM) solution with and without salt (NaCl) and at two different temperatures (35 °C and 70 °C) were evaluated using rheological approaches. Two fumed silica nanoparticles (NPs) featuring different surface chemistries were used, and their ability to prevent destruction of the polymer network structure against salt addition and temperature increase was investigated. Linear rheological tests (frequency sweep, creep, and creep recovery) and nonlinear rheological tests (large amplitude oscillatory shear) were employed to evaluate the network structure of these systems.
1. S Sadeghi, M Arjmand, I Otero Navas, A Zehtab Yazdi, U Sundararaj,
Effect of nanofiller geometry on network formation in polymeric nanocomposites: comparison of rheological and electrical properties of multiwalled carbon nanotube and graphene …, 2017, Macromolecules 50 (10), 3954-3967.
2. M Arjmand, M Mahmoodi, S Park, U Sundararaj, Impact of foaming on the broadband dielectric properties of multi-walled carbon nanotube/polystyrene composites, Journal of Cellular Plastics, 2014, 50 (6), 551-562.
3. M Mahmoodi, M Arjmand, U Sundararaj, S Park, The electrical conductivity and electromagnetic interference shielding of injection molded multi-walled carbon nanotube/polystyrene composites, 2012, Carbon, 50, (4), 1455-1464.
4. GA Gelves, MH Al-Saleh, U Sundararaj, Highly electrically conductive and high performance EMI shielding nanowire/polymer nanocomposites by miscible mixing and precipitation, 2011, GA Gelves, MH Al-Saleh, U Sundararaj, Journal of Materials Chemistry 21 (3), 829-836.
5. MH Al-Saleh, U Sundararaj, Electromagnetic interference shielding mechanisms of CNT/polymer composites, 2009, Carbon 47 (7), 1738-1746.
6. GA Gelves, B Lin, U Sundararaj, JA Haber, Low electrical percolation threshold of silver and copper nanowires in polystyrene composites, 2006, Advanced Functional Materials 16 (18), 2423-2430.
7. R Sharmin, U Sundararaj, S Shah, LV Griend, YJ Sun, Inferential sensors for estimation of polymer quality parameters: Industrial application of a PLS-based soft sensor for a LDPE plant, 2006, Chemical Engineering Science 61 (19), 6372-6384.