@article { ISI:000336353000001, title = {Synthesis and characterization of triad based rigid mesogenic diols derived from hydroquinone and 4-hydroxybenzoic acid}, journal = {Indian Journal of Chemistry Section B-Organic Chemistry Including Medicinal Chemistry}, volume = {53}, number = {5}, year = {2014}, month = {MAY}, pages = {591-596}, publisher = {COUNCIL SCIENTIFIC \& INDUSTRIAL RES}, address = {ANUSANDHAN BHAWAN, 2 RAFI MARG, NEW DELHI, 110001, INDIA}, abstract = {

Triad based rigid mesogenic diols have been synthesized by four step synthesis method using protection-deprotection method. Hydroquinone and 4-hydroxy benzoic acid have been used as starting materials. Synthesized diols have been characterized by IR, H-1 and C-13 NMR, and mass spectroscopic methods. Thermal properties have been determined by thermo gravimetric analysis method and degree of crystallinity have been measured by wide angle X-ray technique. Substituted hydroquinones (methyl and chloro) have been used to study the effect of substitution on physical and thermal properties. Synthesis of rigid mesogenic diol monomer using p-hydroxy benzoic acid and hydroquinone is reported, which is a facile route. Hydrolysis of diacetate derivatives of rigid mesogenic diols is performed in good yields, even though two types of ester groups present in the same moiety, aromatic and aliphatic. The experimental results reveal that hydroquinone based rigid triad mesogenic diol have high thermal stability and degree of crystallinity as compared to methyl-and chloro-substituted rigid triad mesogenic diols.

}, keywords = {degree of crystallinity, ester hydrolysis, Mesogenic diols, spectral properties, Thermal properties}, issn = {0376-4699}, author = {Mulani, Khudbudin Baban and Ganjave, Nitin V. and Chavan, Nayaku} } @article { ISI:000350698600007, title = {Synthesis of novel silica-polyimide nanocomposite films using aromatic-amino modified silica nanoparticles: mechanical, thermal and morphological investigations}, journal = {Express Polymer Letters}, volume = {9}, number = {5}, year = {2015}, month = {MAY}, pages = {469-479}, publisher = {BUDAPEST UNIV TECHNOL \& ECON}, address = {DEPT POLYMER ENG, MUEGYETEM RKP 3, BUDAPEST, H-1111, HUNGARY}, abstract = {

Silica nanoparticles were modified with aromatic amino groups and modified-silica/polyimide composite films were prepared using them. 3,3!, 4,4!-Benzophenone tetracarboxylic dianhydride (BTDA) and 4,4!-oxydianiline (ODA) were used as precursors for polyimide matrix. The structures of the modified nanoparticles and hybrid nanocomposites were identified using Fourier Transform Infrared (FTIR) spectrometry. The hybrid composite films were evaluated for mechanical, thermal and morphological characteristics. Morphological results describe a uniform dispersion of silica particles in the polymer matrix. The thermal stability and mechanical properties of polyimide composite were improved, and the decomposition temperature was increased when the amount of silica nanoparticles was increased.

}, keywords = {hybrid polyimide composites, mechanical properties, Nanocomposites, nanoparticle modification, Thermal properties}, issn = {1788-618X}, doi = {10.3144/expresspolymlett.2015.44}, author = {Ghorpade, Ravindra V. and Rajan, C. R. and Chavan, Nayaku and Ponrathnam, S.} } @article { ISI:000370489600002, title = {Role of aliphatic hydrocarbon content in non-solvating porogens toward porosity of cross-linked microbeads}, journal = {Polymer}, volume = {86}, year = {2016}, month = {MAR}, pages = {8-14}, publisher = {ELSEVIER SCI LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND}, abstract = {

Megaporous spherical acrylate copolymer beads were synthesized by suspension polymerization using non-solvating porogens. Non-solvating porogens with higher aliphatic hydrocarbon content generated megaporous morphology with lower surface area. Surface area increased and inversely megaporosity was decreased with decrease in the aliphatic hydrocarbon content of porogen. Megaporosity (5.47 mu m) and pore volume of 5.52 cm(3)/g was obtained with n-decanol. Thermal property of copolymer is a function of type (rigidity/flexibility/elemental composition) and concentration (cross-link density) of monomer and cross-linker. Copolymer containing rigid cross-linker (divinylbenzene) had better thermal stability over copolymer with flexible cross-linker (ethylene dimethacrylate). Further, higher concentration of rigid cross-linker or lower concentration of flexible cross-linker enhanced the thermal stability. Porous polymers are potentially recognized as a solid support for solid-phase synthesis. (C) 2016 Elsevier Ltd. All rights reserved.

}, keywords = {Cross-linked microbeads, Interfacial tension, Megaporosity, Non-solvating porogens, Thermal properties}, issn = {0032-3861}, doi = {10.1016/j.polymer.2016.01.022}, author = {Mane, Sachin and Badiger, Manohar V. and Rajan, C. R. and Ponrathnam, Surendra and Chavan, Nayaku} } @article { ISI:000379253100009, title = {Synthesis of 2-phenoxy-2-phenylethyl acrylate and copolymerization with 2-phenylethyl acrylate: estimation of monomer reactivity ratios, thermal and optical properties}, journal = {Journal of Macromolecular Science Part A-Pure and Applied Chemistry}, volume = {53}, number = {7}, year = {2016}, month = {MAY}, pages = {457-464}, publisher = {TAYLOR \& FRANCIS INC}, address = {530 WALNUT STREET, STE 850, PHILADELPHIA, PA 19106 USA}, abstract = {

A new aromatic based monomer 2-phenoxy-2-phenylethyl acrylate (PPEA) was synthesized. Copolymers of PPEA with 2-phenylethyl acrylate (PEA) were prepared by free radical polymerization. The reactivity ratios were estimated using various graphical methods. Structural parameters of the copolymers were obtained by calculating the dyad monomer sequence fractions and the mean sequence length. Optical properties of polymers such as refractive indices and UV-Visible absorption were investigated. The glass transition temperature and thermal degradation behavior of the copolymers were studied. Combined with the RI, transparency and thermal properties, prepared copolymers hold great promise as materials for intraocular lens applications.

}, keywords = {2-Phenoxy-2-phenylethyl acrylate, 2-phenylethyl acrylate, copolymerization, Optical properties, reactivity ratios, Thermal properties}, issn = {1060-1325}, doi = {10.1080/10601325.2016.1176447}, author = {Ghorpade, Ravindra V. and Ponrathnam, Surendra and Chavan, Nayaku} }