Sreenivasan, P V; Dr. Philip, Kurian(Cochin University of Science & Technology, October , 2007)
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Abstract:
The present study aims at the preparation of an ABS
(acrylonitrile-butadiene-styrene) type toughened thermoplastic by melt blending polystyrene (PS) and powdered nitrile rubber (NBR). The product is an interesting
class of toughened thermoplastic, which would combine the superior mechanical
and processing characteristics of PS and the excellent oil-resistant properties of
NBR. In this thesis an attempt has been made to investigate systematically the
effect of compatibilisation and dynamic vulcanisation on the morphology and
properties of powdered nitrile rubber toughened polystyrene.
Description:
Department of Polymer Science and Rubber Technology, Cochin University of
Science and Technology
George,K E; Rajan, M; Agarwal, U S; Bally, C; Lemstra, P J(Wiley InterScience, 2005)
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Abstract:
We describe the synthesis of diblock and triblock copolymers by sequential
atom transfer radical polymerization of styrene and acetoxymethylstyrene. Contrary to
the usual block copolymerization involving isolation of the macroinitiator, a convenient
one-pot procedure is developed. This is possible because of the preferential polymerization
of acetoxymethylstyrene, even in the presence of residual styrene, as inferred
from characterization of the intermediate polystyrenes and the block copolymers by size
exclusion chromatography, 1H NMR, Fourier transform infrared spectroscopy, differential
scanning calorimetry, and GPEC techniques. The latent acetoxy functionalities
in these block copolymers are shown to be easily unmasked to OOH and OBr functionalities,
with the potential for block ionomers and dense graft architectures.
Chandrasekaran, M; Rajeev Kumar, S; Keerthi, T R; Sabu, A(Elsevier, September 27, 1999)
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Abstract:
Extracellular L-glutaminase production by Beau6eria sp., isolated from marine sediment, was observed during solid state
fermentation using polystyrene as an inert support. Maximal enzyme production (49.89 U:ml) occurred at pH 9.0, 27°C, in a
seawater based medium supplemented with L-glutamine (0.25% w:v) as substrate and D-glucose (0.5% w:v) as additional carbon
source, after 96 h of incubation. Enzyme production was growth associated. Results indicate scope for production of salt tolerant
L-glutaminase using this marine fungus
Girish Kumar,K; Saji John,Konnully; Remalakshmy,Poduval(Department of Applied Chemistry, April 2, 2005)
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Abstract:
A set of six new polystyrene anchored metal
complexes have been synthesized by the reaction of the
metal salt with the polystyrene anchored Schiff base of
vanillin. These complexes were characterized by elemental
analyses, Fourier transform infrared spectroscopy, diffuse
reflectance studies, thermal studies, and magnetic susceptibility
measurements. The elemental analyses suggest a
metal : ligand ratio of 1 : 2. The ligand is unidentate and
coordinates through the azomethine nitrogen. The Mn(II),
Fe(III), Co(II), Ni(II), and Cu(II) complexes are all paramagnetic
while Zn(II) is diamagnetic. The Cu(II) complex is
assigned a square planar structure, while Zn(II) is assigned
a tetrahedral structure and Mn(II), Fe(III), Co(II), and Ni(II)
are all assigned octahedral geometry. The thermal analyses
were done on the ligand and its complexes to reveal their
stability. Further, the application of the Schiff base as a
chelating resin in ion removal studies was investigated. The
polystyrene anchored Schiff base gave 96% efficiency in the
removal of Ni(II) from a 20-ppm solution in 15 min, without
any interference from ions such as Mn(II), Co(II), Fe(III),
Cu(II), Zn(II), U(VI), Na , K , NH4
, Ca2 , Cl , Br , NO3
,
NO2
,and CH3CO2
. The major advantage is that the removal
is achieved without altering the pH.