02094nas a2200241 4500008004100000022001400041245009900055210006900154260008400223300001200307490000800319520120900327653001301536653001801549653002701567653001901594653002001613653002101633100001701654700003101671700002001702856013001722 2006 eng d a1549-329600aPreparation and characterization of novel hybrid of chitosan-g-lactic acid and montmorillonite0 aPreparation and characterization of novel hybrid of chitosanglac aDIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USAbWILEY-LISScAUG a372-3820 v78A3 a

The utilization of biopolymers and the development of organic-inorganic hybrids are ever increasing interest of material science researchers around the globe for various applications. The present attempt is intended to prepare nanocomposites of lactic acid grafted chitosan and layered silicates. Nanocomposites were prepared by dissolving chitosan and dispersing sodium montmorillonite in aqueous solution of L-lactic acid with subsequent heating and film casting. They were characterized by conventional techniques such as Fourier transform infrared spectroscopy, X-ray diffractometry, thermogravimetric analysis, energy dispersive X-ray spectroscopy, and elemental analysis. The results from polar optical and transmission electron microscopic measurements are also discussed. Sorption behavior of samples has been followed by measuring swelling degree and contact angle. The films have shown enhanced hydrophilicity when compared with polylactic acid (PLA). Issues on the interactions of polycationic chitosan with clay are also discussed. It is observed that nanocomposites are exhibiting better thermal and physical properties than neat chitosang-LA and PLA. (c) 2006 Wiley Periodicals, Inc.

10aChitosan10acontact angle10agraft copolymerization10aNanocomposites10apolylactic acid10awater absorption1 aDepan, Dilip1 aKumar, Annamalai, Pratheep1 aSingh, Raj, Pal uhttps://library.ncl.res.in/content/preparation-and-characterization-novel-hybrid-chitosan-g-lactic-acid-and-montmorillonite-001975nas a2200229 4500008004100000022001400041245009900055210006900154260008400223300001200307490000700319520114300326653001301469653002701482653001901509653000901528653002101537100001701558700002001575700002001595856013001615 2008 eng d a1552-497300aPreparation and characterization of novel hybrid of chitosan-g-PDMS and sodium montmorrilonite0 aPreparation and characterization of novel hybrid of chitosangPDM aDIV JOHN WILEY & SONS INC, 111 RIVER ST, HOBOKEN, NJ 07030 USAbWILEY-LISScJAN a184-1900 v843 a

Preparation and properties of Chitosan (CS)-clay nanocomposites grafted with polydimethyl siloxane (PDMS) with different clay ratios are herein discussed. CS is intercalated into sodium montmorrilonite and PDMS is grafted onto CS under UV irradiation. Sample films of CS intercalated into clay and grafted with PDMS were prepared by solvent casting method with varying amount of nanoclay and PDMS. They were characterized by conventional techniques such as X-ray diffractometry, fourier transform infrared spectroscopy, C-13 NMR, thermo gravimetric analysis, and differential thermal analysis. Sorption behavior of samples has been followed by measuring swelling degree and issues on the interactions of biopolymers with clay are also discussed. The water absorption of composites films reduces with an increase in the amount of incorporated clay. This is due to the barrier formation in the form of cross-linking points, which prevents water permeation into CS. The amount of adsorbed water is more, when the amount of CS exceeds the amount of PDMS. This shows high water retention capacity of CS. (c) 2007 Wiley Periodicals, Inc.

10aChitosan10agraft copolymerization10aNanocomposites10aPDMS10awater absorption1 aDepan, Dilip1 aKumar, Bijandra1 aSingh, Raj, Pal uhttps://library.ncl.res.in/content/preparation-and-characterization-novel-hybrid-chitosan-g-pdms-and-sodium-montmorrilonite-002154nas a2200229 4500008004100000022001400041245012600055210006900181260009900250300001100349490000600360520126800366653001301634653000901647653002301656653002601679653001901705100001701724700003101741700002001772856013201792 2009 eng d a1742-706100aCell proliferation and controlled drug release studies of nanohybrids based on chitosan-g-lactic acid and montmorillonite0 aCell proliferation and controlled drug release studies of nanohy aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcJAN a93-1000 v53 a

The present paper reveals the potential uses of novel hybrids of chitosan-g-lactic acid and sodium montmorillonite (MMT) in controlled drug delivery and tissue engineering applications. The drug-loaded novel nanohybrid films and porous scaffolds have been prepared by solvent casting and freeze-drying of the grafted polymer solution, respectively. Sodium Ibuprofen was loaded into nanohybrids of chitosan-g-lactic acid/sodium montmorillonite (CS-g-LA/MMT). Grafting of lactic acid and the drug loading were characterized by Fourier transform infrared spectroscopy. Formation of intercalated nanocomposites was confirmed by X-ray diffraction. Mechanical properties measurements have shown improvement in modulus and strength with expense of elongation by MMT reinforcement. The nanohybrids were found to be stable regardless of pH of the medium. The cell proliferation profile also shows that prepared nanohybrids are biocompatible. MMT reinforcement was found to control the drug (Ibuprofen) release rate in phosphate buffer saline solution (pH 7.4). MMT clay is therefore a viable additive for formulating sustained drug delivery systems based on lactic acid grafted chitosan. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

10aChitosan10aclay10aControlled release10adrug delivery systems10aNanocomposites1 aDepan, Dilip1 aKumar, Annamalai, Pratheep1 aSingh, Raj, Pal uhttps://library.ncl.res.in/content/cell-proliferation-and-controlled-drug-release-studies-nanohybrids-based-chitosan-g-lactic-002260nas a2200253 4500008004100000022001400041245009700055210006900152260010600221300001200327490000700339520132300346653002101669653000901690653003401699653001901733653001801752653001201770100003101782700001701813700002601830700002001856856013001876 2009 eng d a0079-670000aNanoscale particles for polymer degradation and stabilization-trends and future perspectives0 aNanoscale particles for polymer degradation and stabilizationtre aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJUN a479-5150 v343 a

The field of nanoscience and nanotechnology is extending the applications of physics, chemistry, biology, engineering and technology into previously unapproached infinitesimal length scales. The polymer-nanoparticles/nanocomposites have been the exponentially growing field of research for developing the materials in last few decades and have been mainly focusing on the structure-property relationships and their development. Since the polymer-nanocomposites have been the staple of modern polymer industry, their durability under various environmental conditions and degradability after their service life are also essential fields of research. Thus, this article is intended to review the status of worldwide research in this aspect. Among various nanoparticulates, clay minerals and carbon nanotubes are more often used in enhancing physical, mechanical and thermal properties of polymers. In very few systems, the nano particulates have been incorporated into polymer as `nano-additives' for both purposes: degradation and stabilization of polymers. The degradation and durability of polymers is reviewed in the presence of nanoparticles/nanocomposites under different environmental conditions. Nanoparticle-induced biodegradation of polymers is also discussed. (c) 2009 Elsevier Ltd. All rights reserved.

10aCarbon nanotubes10aclay10aDegradation and stabilization10aNanocomposites10aNanoparticles10aPolymer1 aKumar, Annamalai, Pratheep1 aDepan, Dilip1 aTomer, Namrata, Singh1 aSingh, Raj, Pal uhttps://library.ncl.res.in/content/nanoscale-particles-polymer-degradation-and-stabilization-trends-and-future-perspectives-0