Dr. K E George
http://dyuthi.cusat.ac.in:8080/xmlui/handle/purl/910
2024-02-07T21:28:13ZShort Nylon Fibre Reinforced PP: Melt Rheology
http://dyuthi.cusat.ac.in:8080/xmlui/handle/purl/1999
Short Nylon Fibre Reinforced PP: Melt Rheology
Abraham, Thomas N; George,K E
Short fiber reinforced thermoplastics have generated much
interest these days since fibrous materials tend to increase both
mechanical and thermal properties, such as tensile strength, flexural
strength, flexural modulus, heat deflection temperature, creep
resistance, and some times impact strength of thermoplastics. If
the matrix and reinforcement are both based on polymers the composite
are recyclable. The rheological behavior of recyclable composites
based on nylon fiber reinforced polypropylene (PP) is reported
in this paper. The rheological behavior was evaluated both using a
capillary rheometer and a torque rheometer. The study showed that
the composite became pseudoplastic with fiber content and hence
fiber addition did not affect processing adversely at higher shear
rates. The torque rheometer data resembled that obtained from
the capillary rheometer. The energy of mixing and activation energy
of mixing also did not show much variation from that of PP alone.
2007-01-01T00:00:00ZDynamic mechanical analysis of binary and ternary polymer blends based on nylon copolymer/EPDM rubber and EPM grafted maleic anhydride compatibilizer
http://dyuthi.cusat.ac.in:8080/xmlui/handle/purl/1998
Dynamic mechanical analysis of binary and ternary polymer blends based on nylon copolymer/EPDM rubber and EPM grafted maleic anhydride compatibilizer
George,K E; Komalan, C; Kumar, P A S; Varughese, K T; Thomas, S
The dynamic mechanical properties such as storage modulus, loss modulus and damping properties of blends of
nylon copolymer (PA6,66) with ethylene propylene diene (EPDM) rubber was investigated with special reference to the
effect of blend ratio and compatibilisation over a temperature range –100°C to 150°C at different frequencies. The effect of
change in the composition of the polymer blends on tanδ was studied to understand the extent of polymer miscibility and
damping characteristics. The loss tangent curve of the blends exhibited two transition peaks, corresponding to the glass
transition temperature (Tg) of individual components indicating incompatibility of the blend systems. The morphology of
the blends has been examined by using scanning electron microscopy. The Arrhenius relationship was used to calculate the
activation energy for the glass transition of the blends. Finally, attempts have been made to compare the experimental data
with theoretical models.
2007-01-01T00:00:00ZSilane Grafting of Polyethylenes
http://dyuthi.cusat.ac.in:8080/xmlui/handle/purl/1997
Silane Grafting of Polyethylenes
George,K E; Isac, Sheela
Reactive extrusion is an attractive means of polymer processing since the shaping
and reaction take place in a single operation. In this paper we report the silane
grafting of polyethylenes in a single screw extruder. The optimum conditions for
silane grafting, viz. temperature, shear rate, silane and DCP concentrations, were
determined on a torque rheometer and then actual extrusion was performed
using these conditions. The study shows that an optimum low level of grafting/
crosslinking can be introduced into polyethylene during its extrusion for better
mechanical behavior and=or thermal stability without affecting the processability.
2005-01-01T00:00:00ZModification of Polypropylene/Glass Fiber Composites with Nanosilica
http://dyuthi.cusat.ac.in:8080/xmlui/handle/purl/1996
Modification of Polypropylene/Glass Fiber Composites with Nanosilica
George,K E; Jacob, Sinto; Suma, K K; Mendaz, Jude Martin; George, Abhilash
Poly(propylene) (PP) reinforced with short glass fiber was modified with
precipitated nanosilica (pnS) by melt mixing. The weight of the glass fiber was varied
by keeping the pnS at optimum level. The properties of the composites were studied
using universal testing machine, dynamic mechanic analyser (DMA), differential
Scanning calorimetry (DSC) and thermo gravimetric analyser (TGA). The amount of the
glass fiber required for a particular modulus could be reduced by the addition of
nanosilica.
2009-01-01T00:00:00Z