<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pujari, N. S.</style></author><author><style face="normal" font="default" size="100%">Kulkarni, M. R.</style></author><author><style face="normal" font="default" size="100%">Large, M. C. J.</style></author><author><style face="normal" font="default" size="100%">Bassett, I. M.</style></author><author><style face="normal" font="default" size="100%">Ponrathnam, S.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transparent chiral polymers for optical applications</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Applied Polymer Science</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">chiral</style></keyword><keyword><style  face="normal" font="default" size="100%">cholesteryl methacrylate</style></keyword><keyword><style  face="normal" font="default" size="100%">optically active</style></keyword><keyword><style  face="normal" font="default" size="100%">plastic optical fiber</style></keyword><keyword><style  face="normal" font="default" size="100%">poly(cholesteryl methacrylate)</style></keyword><keyword><style  face="normal" font="default" size="100%">poly(cholesteryl methacrylate-co-methyl methacrylate)</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2005</style></year><pub-dates><date><style  face="normal" font="default" size="100%">OCT</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">1</style></number><publisher><style face="normal" font="default" size="100%">WILEY-BLACKWELL</style></publisher><pub-location><style face="normal" font="default" size="100%">COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA</style></pub-location><volume><style face="normal" font="default" size="100%">98</style></volume><pages><style face="normal" font="default" size="100%">58-65</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Optically active chiral polymers and copolymers of cholesteryl methacrylate have been studied for use in optical applications including plastic optical fibers. Homopolymers of chiral cholesteryl methacrylate with differing molecular weights and copolymers with methyl methacrylate were synthesized by free-radical copolymerization in tetrahydrofuran using azobisisobutyronitrile at 67 degrees C for 26 h. All polymers were characterized for molecular weight, glass-transition temperature, optical rotation, transparency, and refractive index and solution blended to test for compatibility with poly(methyl methacrylate). Such chiral materials are of particular interest because they offer useful polarization properties without requiring bulk orientation of the molecules. This makes it possible to produce low cost optical elements such as circularly birefringent or circularly polarizing optical elements with potential applications in polarization manipulations and sensing. (c) 2005 Wiley Periodicals, Inc.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">1.866</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nikam, Shrikant B.</style></author><author><style face="normal" font="default" size="100%">Singh, Chandrodai Pratap</style></author><author><style face="normal" font="default" size="100%">Krishnamurty, Sailaja</style></author><author><style face="normal" font="default" size="100%">Asha, S. K.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Structure-property insights into chiral thiophene copolymers by direct heteroarylation polymerization</style></title><secondary-title><style face="normal" font="default" size="100%">European Polymer Journal</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">chiral</style></keyword><keyword><style  face="normal" font="default" size="100%">DFT</style></keyword><keyword><style  face="normal" font="default" size="100%">Direct heteroarylation polymerization</style></keyword><keyword><style  face="normal" font="default" size="100%">Gibb?s free energy</style></keyword><keyword><style  face="normal" font="default" size="100%">Steric Hindrance</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2022</style></year><pub-dates><date><style  face="normal" font="default" size="100%">DEC </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">181</style></volume><pages><style face="normal" font="default" size="100%">111676</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	Chiral thiophene copolymers with fluorene as co monomer are designed having N-Boc-L-glutamic acid-1-tert-butyl ester as a chiral substituent located either on the thiophene unit or the fluorene unit with varying spacer length. The atom-economic direct heteroarylation polymerization (DHAP) method is utilized for the polymerization. Gibb's free energy (delta G) for polymerization determined using DFT calculations indicate difficulty in achieving high molar mass when the bulky chiral substituents are attached through short spacer to the backbone. The experimental observations are in agreement with the theoretical calculations with no polymer-ization or very low molar mass sticky compounds obtained for reactions with predicted + &amp;amp; UDelta;G values. Structure -property relationship are compared for two chiral polymers -P4 and P5 having the chiral substitution on thiophene and fluorene units respectively. No CD signal is observed in THF-a good solvent where the polymers are molecularly dissolved. Intense bisignated CD signal is observed for both polymers upon addition of methanol - a poor solvent, to their THF solution. The bisignate CD signal with maxima at lower wavelength and inflection point associated with the pi-pi* absorption band is characteristic of exciton coupling between polymer chains in a left handed helical orientation. Small differences are observed in the intensity of the CD signal for the polymers P4 and P5 highlighting the impact of steric hindrance of bulky pendant groups on polymer conformation. DHAP is an atom economic polymerization procedure that can be gainfully utilized for developing chiral conjugated polymers.&lt;/p&gt;
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	Foreign&lt;/p&gt;
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	5.546&lt;/p&gt;
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