Aiswarya, N.; Dr. M.R. Prathapachandra Kurup(Cochin University of Science and Technology, April 10, 2016)
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Abstract:
The current scenario of coordination chemistry is witnessing the exploitation
of coordination bonds and noncovalent interactions to generate self-assemblies of
various dimensions having not only aesthetic values but also countless applications
and that paved way for supramolecular chemistry/crystal engineering. Most of
such fascinating work employs Schiff bases obtained by the condenzation of an
amine and a carbonyl compound. The use of diamines in the synthesis of highnuclearity
complexes utilizes the bridging capacity of phenoxo atoms. Whereas in
the case of N2O donor tridentate Schiff bases (N-substituted diamines with
salicylaldehyde or its derivatives), coligands are employed to generate structures of
variable composition apart from satisfying the coordination number. Among the
various coligands known, pseudohalides (azido, cyanato, thiocyanato, dicyanamido)
deserve special attention on account of its versatile modes of binding. In addition
to the structural variety, such Schiff base complexes have its signature in the field
of catalysis, luminescence, gas adsorption and magnetic materials which make the
arena conspicuous. The recognition of plasticity of copper(II) metal with respect to
its coordination number and its ubiquitous nature as active sites in many metalloenzymes
fuelled us to work with this metal. The results of our efforts to explore
the role of various interaction forces constitute the subject matter of the thesis
entitled “Crystalline architectures of copper(II) complexes derived from halogen
substituted carbonyl compounds: Interplay of covalent and non-covalent forces”.
The work embodied in this thesis was carried out by the author in the Department of
Applied Chemistry, CUSAT, Kochi, during the period 2011-2016 and is divided into
eight chapters.
Gisha Elizabeth, Luckachan; Dr. C K S Pillai(Regional Research Laboratory (CSIR), May , 2006)
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Abstract:
Biodegradable polymers have opened an emerging area of great interest
because they are the ultimate solution for the disposal problems of synthetic
polymers used for short time applications in the environmental and biomedical
field. The biodegradable polymers available until recently have a number of
limitations in terms of strength and dimensional stability. Most of them have
processing problems and are also very expensive. Recent developments in
biodegradable polymers show that monomers and polymers obtained from
renewable resources are important owing to their inherent biodegradability,
biocompatibility and easy availability. The present study is, therefore, mostly
concemed with the utilization of renewable resources by effecting chemical
modification/copolymerization on existing synthetic polymers/natural polymers
for introducing better biodegradability and material properties.The thesis describes multiple approaches in the design of new
biodegradable polymers: (1) Chemical modification of an existing nonbiodegradable
polymer, polyethylene, by anchoring monosaccharides after
functionalization to introduce biodegradability. (2) Copolymerization of an
existing biodegradable polymer, polylactide, with suitable monomers and/or
polymers to tailor their properties to suit the emerging requirements such as
(2a) graft copolymerization of lactide onto chitosan to get controlled solvation
and biodegradability and (2b) copolymerization of polylactide with cycloaliphatic amide segments to improve upon the thermal properties and
processability.