@article { ISI:000254004400057,
	title = {New poly(phenylene oxide)/polystyrene blend nanocomposites with clay: intercalation, thermal and mechanical properties},
	journal = {Journal of Applied Polymer Science},
	volume = {108},
	number = {3},
	year = {2008},
	month = {MAY},
	pages = {1818-1828},
	publisher = {JOHN WILEY \& SONS INC},
	address = {111 RIVER ST, HOBOKEN, NJ 07030 USA},
	abstract = {<p>We present the first study and results on the preparation and characterization of montmorillonite clay filter based polymer blend nanocomposites of the miscible poly(phenylene oxide)/polystyrene blend. Intercalated nanocomposites, prepared by a melt-processing method with 2-6 wt \% commercially available organically modified sodium montmorillonite, have been characterized with wide-angle X-ray diffraction, transmission electron microscopy analysis, thermal analysis (thermogravimetric analysis and differential scanning calorimetry), and mechanical tensile tests. We show that nanocomposites can be successfully prepared in a batch mixer at temperatures much below the conditions conventionally used for this blend without organic degradation. Thermal stability is enhanced by nanoscale hybrid formation. The level of intercalation (change in the d-spacing) does not change with the clay loading. Better dispersion of clay in the blend matrix has been observed at a low level of clay content. The nanocomposites show improved tensile modulus (by 31\%) in comparison to the blend, whereas the tensile strength (stress at break) and elongation decrease in the presence of the filler with an increase in the clay loading. The Halpin-Tsai model is able to predict the modulus of the nanocomposites in very good agreement with the experimental data. (c) 2008 Wiley Periodicals, Inc.</p>},
	keywords = {mechanical properties, Nanocomposites, organoclay, poly(phenylene oxide), Polystyrene, Thermal properties},
	issn = {0021-8995},
	doi = {10.1002/app.27743},
	author = {Tiwari, Rajkiran R. and Khilar, Kartic C. and Natarajan, Upendra}
}
@article { ISI:000289575500018,
	title = {Effect of composition on chain dimensions of styrene-methylmethacrylate random copolymers under theta condition},
	journal = {Journal of Macromolecular Science Part B-Physics},
	volume = {50},
	number = {5},
	year = {2011},
	month = {APR},
	pages = {996-1005},
	publisher = {TAYLOR \& FRANCIS INC},
	address = {325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA},
	abstract = {<p>Rotational-isomeric-state (RIS)-Metropolis Monte Carlo simulations are performed on poly(styrene-ran-methylmethacrylate) random copolymers to study the intrinsic unperturbed (theta-condition) dimensions. Mean-squared end-to-end distance (\&lt; r(2)\&gt;(o)), mean-squared radius of gyration (\&lt; s(2)\&gt;(o)), and characteristic ratio (C(n)) have been calculated for these copolymers constituted by different overall chemical compositions (styrene fractions 0.29, 0.56, and 0.70). Calculations were carried out with chains of 500 repeating units. With an increase in the styrene content there is an increase in (\&lt; r(2)\&gt;(o)), {\textquoteleft}, and C(n), in agreement with experimental observations. An increase in the fraction of trans conformational states in the backbone torsion angles is found to be responsible for the exhibited chain expansion behavior. The dimensions calculated by the Monte Carlo simulations agree well with experimental values reported in the literature.</p>},
	keywords = {chain dimensions, Monte Carlo, poly(methyl methacrylate), Polystyrene, random copolymer, theta conditions},
	issn = {0022-2348},
	doi = {10.1080/00222348.2010.497414},
	author = {Karyappa, Rahul B. and Natarajan, Upendra}
}
