Composite face sheets were prepared in order to attach with the Nomex® core honeycomb structure f... more Composite face sheets were prepared in order to attach with the Nomex® core honeycomb structure for the manufacturing of composite sandwich panels for aero space applications. Nano reinforcements including carbon nano tubes (CNTs) and nano diamonds (NDs) were reinforced in the epoxy matrix along with carbon fibers to fabricate composite face sheets. The micro-nano composites were characterized mechanically and micro structurally by tensile testing and scanning electron microscopy (SEM). Uniform dispersion of both the nano-fillers was ensured by microscopic techniques. It was found that a uniform dispersion and distribution of nano reinforcement led to an increase in the mechanical performance of the composites.
Covers various topics in Advanced Materials such as: polymer composites, nanocomposites, ceramics... more Covers various topics in Advanced Materials such as: polymer composites, nanocomposites, ceramics, thin-film coatings and shape-memory alloys.
Biological parameters of Papilio demoleus Linnaeus, the Citrus Butterfly, in Tando Muhammad Khan,... more Biological parameters of Papilio demoleus Linnaeus, the Citrus Butterfly, in Tando Muhammad Khan, lower Sindh, Pakistan are presented. This major agricultural pest was reared on Murraya koenigii (L.) Spreng. (Curry Leaf) and ten different varieties of Citrus sp. (Citrus) plants. The length of the adult mating period ranged 5 to 8 hours. Following mating, females laid 27.7 ± 3.3 eggs. Eggs hatched in 1.5 to 7 days. Mean durations of larval instars were 1.8 ± 0.1 (minimum) and 2.9 ± 0.1 (maximum) days respectively. Pupal duration was 5.5 to 20 days. Biotic factors including predators [praying mantis, ants, Common Garden Lizard (Calotes versicolor)] and parasitoids [Trichogramma chilonis, Pteromalus puparum] played a significant role in mortality in all stages of the butterfly. Survival in most life stages had a negative correlation with temperature. Thirteen generations of P. demoleus per year were recorded. The feeding effect of Curry Leaf and ten different Citrus varieties on butter...
This paper reports a study based on a novel concept of ‘self-healing’ coatings applied onto the b... more This paper reports a study based on a novel concept of ‘self-healing’ coatings applied onto the brittle fibre surface to reduce the stress concentrations and thus to improve the reinforcing efficiency in a composite. The individual E-glass fibres as well as rovings were coated with a carbon nanotube (CNT) reinforced epoxy composite. The tensile strengths were measured for the individual and bundle fibres, which were treated statistically to determine the Weibull parameters and thus to evaluate the notch sensitivity of the fibres with and without coating. The results indicate that the tensile strength of the individual fibre increased by 10% after coating with neat epoxy. Coating with epoxy nanocomposite containing 0.3wt% MWNT further improved the tensile strength. However, increasing the nanotube content was not necessarily beneficial due to the formation of nanotube agglomerates within the matrix. The tensile tests on fibre roving also showed a clear trend of beneficial effect of n...
The influence of nanoclay on the impact damage resistance of carbon fiber-epoxy (CFRP) composites... more The influence of nanoclay on the impact damage resistance of carbon fiber-epoxy (CFRP) composites has been investigated using the low-velocity impact and compression after impact tests. The load-energy vs time relations were analyzed to gain insight into the damage behaviors of the materials. Compression-after-impact (CAI) test was performed to measure the residual compressive strength. The CFRPs containing organoclay brought about a significant improvement in impact damage resistance and damage tolerance. The composites containing organoclay exhibited an enhanced energy absorption capability with less damage areas and higher CAI strengths compared to those made from neat epoxy. A 3wt% phr was shown to be an optimal content with the highest damage resistance.
ABSTRACT Homopolymers of chlorotrifluoroethylene (CTFE), vinylidene fluoride (VDF) and methyl met... more ABSTRACT Homopolymers of chlorotrifluoroethylene (CTFE), vinylidene fluoride (VDF) and methyl methacrylate (MMA) and their copolymers were studied by PGC/IR with regard to the separation and identification of the degraded products and clarification of the degradation mechanism. Besides monomers, HCl CO2, C2H2, HF, C5H10O2, C3F5Cl and dimers are the observed pyrolysis products. Mechanisms for different degradation reactions have also been studied.
Composite face sheets were prepared in order to attach with the Nomex® core honeycomb structure f... more Composite face sheets were prepared in order to attach with the Nomex® core honeycomb structure for the manufacturing of composite sandwich panels for aero space applications. Nano reinforcements including carbon nano tubes (CNTs) and nano diamonds (NDs) were reinforced in the epoxy matrix along with carbon fibers to fabricate composite face sheets. The micro-nano composites were characterized mechanically and micro structurally by tensile testing and scanning electron microscopy (SEM). Uniform dispersion of both the nano-fillers was ensured by microscopic techniques. It was found that a uniform dispersion and distribution of nano reinforcement led to an increase in the mechanical performance of the composites.
Covers various topics in Advanced Materials such as: polymer composites, nanocomposites, ceramics... more Covers various topics in Advanced Materials such as: polymer composites, nanocomposites, ceramics, thin-film coatings and shape-memory alloys.
Biological parameters of Papilio demoleus Linnaeus, the Citrus Butterfly, in Tando Muhammad Khan,... more Biological parameters of Papilio demoleus Linnaeus, the Citrus Butterfly, in Tando Muhammad Khan, lower Sindh, Pakistan are presented. This major agricultural pest was reared on Murraya koenigii (L.) Spreng. (Curry Leaf) and ten different varieties of Citrus sp. (Citrus) plants. The length of the adult mating period ranged 5 to 8 hours. Following mating, females laid 27.7 ± 3.3 eggs. Eggs hatched in 1.5 to 7 days. Mean durations of larval instars were 1.8 ± 0.1 (minimum) and 2.9 ± 0.1 (maximum) days respectively. Pupal duration was 5.5 to 20 days. Biotic factors including predators [praying mantis, ants, Common Garden Lizard (Calotes versicolor)] and parasitoids [Trichogramma chilonis, Pteromalus puparum] played a significant role in mortality in all stages of the butterfly. Survival in most life stages had a negative correlation with temperature. Thirteen generations of P. demoleus per year were recorded. The feeding effect of Curry Leaf and ten different Citrus varieties on butter...
This paper reports a study based on a novel concept of ‘self-healing’ coatings applied onto the b... more This paper reports a study based on a novel concept of ‘self-healing’ coatings applied onto the brittle fibre surface to reduce the stress concentrations and thus to improve the reinforcing efficiency in a composite. The individual E-glass fibres as well as rovings were coated with a carbon nanotube (CNT) reinforced epoxy composite. The tensile strengths were measured for the individual and bundle fibres, which were treated statistically to determine the Weibull parameters and thus to evaluate the notch sensitivity of the fibres with and without coating. The results indicate that the tensile strength of the individual fibre increased by 10% after coating with neat epoxy. Coating with epoxy nanocomposite containing 0.3wt% MWNT further improved the tensile strength. However, increasing the nanotube content was not necessarily beneficial due to the formation of nanotube agglomerates within the matrix. The tensile tests on fibre roving also showed a clear trend of beneficial effect of n...
The influence of nanoclay on the impact damage resistance of carbon fiber-epoxy (CFRP) composites... more The influence of nanoclay on the impact damage resistance of carbon fiber-epoxy (CFRP) composites has been investigated using the low-velocity impact and compression after impact tests. The load-energy vs time relations were analyzed to gain insight into the damage behaviors of the materials. Compression-after-impact (CAI) test was performed to measure the residual compressive strength. The CFRPs containing organoclay brought about a significant improvement in impact damage resistance and damage tolerance. The composites containing organoclay exhibited an enhanced energy absorption capability with less damage areas and higher CAI strengths compared to those made from neat epoxy. A 3wt% phr was shown to be an optimal content with the highest damage resistance.
ABSTRACT Homopolymers of chlorotrifluoroethylene (CTFE), vinylidene fluoride (VDF) and methyl met... more ABSTRACT Homopolymers of chlorotrifluoroethylene (CTFE), vinylidene fluoride (VDF) and methyl methacrylate (MMA) and their copolymers were studied by PGC/IR with regard to the separation and identification of the degraded products and clarification of the degradation mechanism. Besides monomers, HCl CO2, C2H2, HF, C5H10O2, C3F5Cl and dimers are the observed pyrolysis products. Mechanisms for different degradation reactions have also been studied.
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Papers by Arshad Munir