In recent years conventional mass separation techniques such as distillation, crystallization sol... more In recent years conventional mass separation techniques such as distillation, crystallization solvent extraction, etc., have been supplemented by a class of processes that utilize semipermeable membranes as the essential element for the separation of molecular or particulate mixtures (1,2). Membrane processes can be very different in their application, in the structures used as the separating barrier, and in the driving forces used for the transport of different chemical components. Separations with synthetic membranes have become increasingly important processes in the chemical industry, in food and wastewater processing, and in medical treatment. Synthetic membranes made from a variety of polymers are used in processes such as microfiltration, ultrafiltration, reverse osmosis, electrodialysis, and gas separations. Membrane separation processes are very different in their mode of operations and their application, several common features make them particularly attractive (4,5) In many cases membrane processes are faster, more efficient and economical than conventional separation techniques (6). Current work proposes the preparation of CMC/ PEG blend hydrogel membrane crosslinked and modified by TiO2 for water separation process. Methods: CMC solution was taken, and PEG solution was added to it, cross linking agent citric acid (CA) were added as per the formulations and mixed well. The solutions were casted and allowed to dry in an oven to remove the water in the sequence. Different concentrations of PEG were prepared as in the above and CA added to each of the solutions and casted. Same formulations were made with TiO2, each of the solutions casted and dried in an oven. Membrane preparation: The preparation of membranes was carried out at various compositions. Membranes were obtained by casting prescribed amounts of solutions on to petridishes followed by drying at 70 o C for 6 hours. The films were peeled off. All films were white in color and free of air bubbles and the yield was determined. Results & Discussions: Tensile properties of CMC / PEG blend membrane prepared and the Tensile properties of membranes with Various ratios of TiO2 added when PEG is added the tensile properties decreased and on TiO2 addition, strength increase upto 4% loading and then decreases. This will be due to the dilution effect of the fillers in the matrices. The thermal transitions without TiO2 and with TiO2 respectively and it is clear that not much change it the transitions occur when TiO2 is added to the system. Therefore, can be worked in the similar manner with respect to temperature. Conclusions: In CMC/PEG (CA) with TIO2 membranes alkali resistance decreases with increasing concentration of both PEG and TIO2. In the case of CMC/PEG (CA) without TIO2 alkali resistance increases with increasing concentration of PEG. In both cases acid resistance decreases with increasing concentration of PEG. Heat resistance decreases with increasing concentration of PEG. CMC/PEG (CA) with TIO2 water absorption decreases with increasing concentration of both PEG and TIO2 because they are hydrophobic in nature. CMC/PEG (CA) without TIO2 water absorption increases with increasing concentration of PEG because they are hydrophilic in nature.
People have been searching for tougher and more durable structural material. Intelligent material... more People have been searching for tougher and more durable structural material. Intelligent material systems defined as self-healing composites have been developed. They are capable of automatic recovery and adaptation to environmental changes in a dynamic manner, unlike traditional tough and static composites. Through self-healing, it is expected that safety and reliability will improve, the cost of maintaining artificial composites will decrease and material life will be extended. Inspired by wound healing of biological systems, polymeric systems that utilise reversible and irreversible reactions resulting in regaining macroscopic properties with relatively small energy inputs are of particular focus. This system gives a general design strategy for the development of self-healable polymer systems. Various polymeric microcapsules were synthesised, characterised and incorporated into diverse matrices and examined. The current study involves preparation of microcapsules containing a liq...
Fullerenes can be functionalized with hydrophilic and hydrophobic groups to overcome the solubili... more Fullerenes can be functionalized with hydrophilic and hydrophobic groups to overcome the solubility behavior which enhances its physicochemical properties and promotes their dispersion and strong adherence in polymer matrices. Fullerene derivatives have better miscibility with host polymers without agglomeration; can have a wide range of applications. The membrane plays the most pivotal role in the pervaporation (PV) process and is of great importance in governing the overall efficiency. Nanodiamond are typically about 2–8 nm in diameter. They have unique characteristics of diamonds such as stiffness, hardness, chemical and stability strength and also have the advantages of nanomaterials such as small size, high adsorption capacity, and large surface area. Over conventional materials, it has superior chemical and physical properties of Fullerene-modified PV membranes have a great scope for extensive research. The current chapter deals with the latest developments in the applications...
Engineering plastics are expanding their applications in the immerging world replacing metal comp... more Engineering plastics are expanding their applications in the immerging world replacing metal components and reducing weight and amongst most two of them are selected to study their blending behavior. Nylon-66(N-66) and Acrylonitrile butadiene styrene (ABS) copolymer were blended in basic conventional manner i.e. simple physical melt blending in various proportions. The reason for blending both the polymers is to study their morphology, miscibility and compatibility of blends at various ratios. Blends were studied for mechanical properties i.e. tensile strength, flexural strength, izod impact strength, etc. Blend with optimized level of mechanical property was studied for thermal properties by differential scanning calorimeter (DSC) and thermo gravimetric analysis (TGA). The morphology was studied by scanning electron icroscopy (SEM). m
2013 7th International Conference on Intelligent Systems and Control (ISCO), 2013
Dc power supplies are extensively used inside most of electrical and electronic appliances such a... more Dc power supplies are extensively used inside most of electrical and electronic appliances such as in computers, televisions, audio sets and others. In this paper a bridgeless power factor correction boost converter is proposed which results in improved power factor and reduced harmonics content in input line currents as compared to conventional boost converter topology. Bridgeless power factor correction boost converter eliminates the line-voltage bridge rectifier in conventional boost power factor correction converter, so that the conduction loss is reduced. A good tradeoff between efficiency, dc bus capacitor voltage stress, and harmonic content can be achieved by properly tuning the converter parameters.
Rubber solutions were prepared and used for bonding wood pieces. The effect of the variation of c... more Rubber solutions were prepared and used for bonding wood pieces. The effect of the variation of chlorinated natural rubber (CNR) and phenolformaldehyde (PF) resin in the adhesive solutions on lap shear strength was determined. Natural rubber and neoprene-based adhesive solutions were compared for their lap shear strength. The storage stability of the adhesive prepared was determined. The change in lap shear strength before and after being placed in cold water, hot water, acid, and alkali was tested. The bonding character of these adhesives was compared with different commercially available solution adhesives. The room-temperature aging resistance of wood joints was also determined. In all the studies, the adhesive prepared in the laboratory was found to be superior compared to the commercial adhesives.
Abstract-Natural rubber latex-based adhesives were prepared for wood-to-wood bonding. The effects... more Abstract-Natural rubber latex-based adhesives were prepared for wood-to-wood bonding. The effects of prevulcanization, and varying amounts of ammonium caseinate, carboxymethyl cellulose, cooked starch, and phenol formaldehyde resin on adhesion were studied. The ...
International Journal of Polymeric Materials, 1996
... Use of amine terminated liquid natural rubber as a plasticiser in filled NR and NBR compounds... more ... Use of amine terminated liquid natural rubber as a plasticiser in filled NR and NBR compounds. Auteur(s) / Author(s). SRILATHAKUTTY R. (1) ; JOHN N. (1) ; JOSEPH R. (1) ; GEORGE KE (1) ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). (1) Dept. ...
Melt blending of thermoplastic polyurethane (TPU) with polyolefins (PO’s) can lower the cost and ... more Melt blending of thermoplastic polyurethane (TPU) with polyolefins (PO’s) can lower the cost and improve mechanical and chemical properties. Since TPU and PO’s are completely immiscible polymers, property enhancement cannot be attained. Effect of incorporation of polypropylene copolymer (PPCP), TPU-g-MA, TPU-g- AA as compatibiliser on the miscibility of the blends and effect of clay filler on the mechanical properties were studied. Blends were produced by melt mixing using a single screw extruder. Mechanical and morphological properties were studied. The results show that the blend of thermoplastic polyurethane (TPU)/PO’s with suitable compatibiliser and clay gives excellent performance in all aspects.
Thermoplastic Polyurethane (TPU) is a highly versatile material with superior physical properties... more Thermoplastic Polyurethane (TPU) is a highly versatile material with superior physical properties but high cost. Melt blending of TPU with Polyolefins (PO) can lower the cost and improve mechanical and chemical properties. Since TPU and PO are completely immiscible polymers, property enhancement cannot be attained. Effect of incorporation of Polypropylene Copolymer (PPCP) as compatibilizer on the miscibility of the blends and effect of calcium carbonate as filler to enhance the mechanical properties were studied. Blends were produced by melt mixing using a single screw extruder. Miscibility studies were done using Scanning Electron Microscope (SEM) and thermal characteristics were determined using Differential Scanning Calorimeter (DSC). Mechanical properties like tensile strength, impact strength, flexural strength and hardness were also studied using Universal Testing Machine (UTM). The results show that the blend having 20% loading of polyurethane (PU) with suitable compatibilizers and calcium carbonate gives excellent performance in all aspects.
Blends of Nylon-66/ABS were prepared in various proportions. ABS was chemically modified using et... more Blends of Nylon-66/ABS were prepared in various proportions. ABS was chemically modified using ethylene glycol, ethylene diamine and acrylamide. Butadiene region of ABS acted as site for modification reactions, irradiated by UV using UV initiator in UV reactor. m-ABS were characterized using FTIR confirming chemical functionalization. m-ABS blended with Nylon-66 and results compared with original ABS/N-66 blends. Physical, mechanical, chemical,
International Journal of Polymeric Materials, 2011
Acrylonitrile butadiene styrene (ABS) was grafted using long chain molecules like oleic acid and ... more Acrylonitrile butadiene styrene (ABS) was grafted using long chain molecules like oleic acid and dodecylamine. Grafting took place at the butadiene region of ABS. Grafted ABS (g-ABS) polymers were characterized using FTIR and blended with nylon-66 in various proportions. Physical, chemical, mechanical and thermal properties of the blends were analyzed. A physical blending technique was followed between nylon-66 and ABS
International Journal of Polymeric Materials, 2011
Acrylonitrile butadiene styrene (ABS) was grafted using long chain molecules like oleic acid and ... more Acrylonitrile butadiene styrene (ABS) was grafted using long chain molecules like oleic acid and dodecylamine. Grafting took place at the butadiene region of ABS. Grafted ABS (g-ABS) polymers were characterized using FTIR and blended with nylon-66 in various proportions. Physical, chemical, mechanical and thermal properties of the blends were analyzed. A physical blending technique was followed between nylon-66 and ABS
In recent years conventional mass separation techniques such as distillation, crystallization sol... more In recent years conventional mass separation techniques such as distillation, crystallization solvent extraction, etc., have been supplemented by a class of processes that utilize semipermeable membranes as the essential element for the separation of molecular or particulate mixtures (1,2). Membrane processes can be very different in their application, in the structures used as the separating barrier, and in the driving forces used for the transport of different chemical components. Separations with synthetic membranes have become increasingly important processes in the chemical industry, in food and wastewater processing, and in medical treatment. Synthetic membranes made from a variety of polymers are used in processes such as microfiltration, ultrafiltration, reverse osmosis, electrodialysis, and gas separations. Membrane separation processes are very different in their mode of operations and their application, several common features make them particularly attractive (4,5) In many cases membrane processes are faster, more efficient and economical than conventional separation techniques (6). Current work proposes the preparation of CMC/ PEG blend hydrogel membrane crosslinked and modified by TiO2 for water separation process. Methods: CMC solution was taken, and PEG solution was added to it, cross linking agent citric acid (CA) were added as per the formulations and mixed well. The solutions were casted and allowed to dry in an oven to remove the water in the sequence. Different concentrations of PEG were prepared as in the above and CA added to each of the solutions and casted. Same formulations were made with TiO2, each of the solutions casted and dried in an oven. Membrane preparation: The preparation of membranes was carried out at various compositions. Membranes were obtained by casting prescribed amounts of solutions on to petridishes followed by drying at 70 o C for 6 hours. The films were peeled off. All films were white in color and free of air bubbles and the yield was determined. Results & Discussions: Tensile properties of CMC / PEG blend membrane prepared and the Tensile properties of membranes with Various ratios of TiO2 added when PEG is added the tensile properties decreased and on TiO2 addition, strength increase upto 4% loading and then decreases. This will be due to the dilution effect of the fillers in the matrices. The thermal transitions without TiO2 and with TiO2 respectively and it is clear that not much change it the transitions occur when TiO2 is added to the system. Therefore, can be worked in the similar manner with respect to temperature. Conclusions: In CMC/PEG (CA) with TIO2 membranes alkali resistance decreases with increasing concentration of both PEG and TIO2. In the case of CMC/PEG (CA) without TIO2 alkali resistance increases with increasing concentration of PEG. In both cases acid resistance decreases with increasing concentration of PEG. Heat resistance decreases with increasing concentration of PEG. CMC/PEG (CA) with TIO2 water absorption decreases with increasing concentration of both PEG and TIO2 because they are hydrophobic in nature. CMC/PEG (CA) without TIO2 water absorption increases with increasing concentration of PEG because they are hydrophilic in nature.
People have been searching for tougher and more durable structural material. Intelligent material... more People have been searching for tougher and more durable structural material. Intelligent material systems defined as self-healing composites have been developed. They are capable of automatic recovery and adaptation to environmental changes in a dynamic manner, unlike traditional tough and static composites. Through self-healing, it is expected that safety and reliability will improve, the cost of maintaining artificial composites will decrease and material life will be extended. Inspired by wound healing of biological systems, polymeric systems that utilise reversible and irreversible reactions resulting in regaining macroscopic properties with relatively small energy inputs are of particular focus. This system gives a general design strategy for the development of self-healable polymer systems. Various polymeric microcapsules were synthesised, characterised and incorporated into diverse matrices and examined. The current study involves preparation of microcapsules containing a liq...
Fullerenes can be functionalized with hydrophilic and hydrophobic groups to overcome the solubili... more Fullerenes can be functionalized with hydrophilic and hydrophobic groups to overcome the solubility behavior which enhances its physicochemical properties and promotes their dispersion and strong adherence in polymer matrices. Fullerene derivatives have better miscibility with host polymers without agglomeration; can have a wide range of applications. The membrane plays the most pivotal role in the pervaporation (PV) process and is of great importance in governing the overall efficiency. Nanodiamond are typically about 2–8 nm in diameter. They have unique characteristics of diamonds such as stiffness, hardness, chemical and stability strength and also have the advantages of nanomaterials such as small size, high adsorption capacity, and large surface area. Over conventional materials, it has superior chemical and physical properties of Fullerene-modified PV membranes have a great scope for extensive research. The current chapter deals with the latest developments in the applications...
Engineering plastics are expanding their applications in the immerging world replacing metal comp... more Engineering plastics are expanding their applications in the immerging world replacing metal components and reducing weight and amongst most two of them are selected to study their blending behavior. Nylon-66(N-66) and Acrylonitrile butadiene styrene (ABS) copolymer were blended in basic conventional manner i.e. simple physical melt blending in various proportions. The reason for blending both the polymers is to study their morphology, miscibility and compatibility of blends at various ratios. Blends were studied for mechanical properties i.e. tensile strength, flexural strength, izod impact strength, etc. Blend with optimized level of mechanical property was studied for thermal properties by differential scanning calorimeter (DSC) and thermo gravimetric analysis (TGA). The morphology was studied by scanning electron icroscopy (SEM). m
2013 7th International Conference on Intelligent Systems and Control (ISCO), 2013
Dc power supplies are extensively used inside most of electrical and electronic appliances such a... more Dc power supplies are extensively used inside most of electrical and electronic appliances such as in computers, televisions, audio sets and others. In this paper a bridgeless power factor correction boost converter is proposed which results in improved power factor and reduced harmonics content in input line currents as compared to conventional boost converter topology. Bridgeless power factor correction boost converter eliminates the line-voltage bridge rectifier in conventional boost power factor correction converter, so that the conduction loss is reduced. A good tradeoff between efficiency, dc bus capacitor voltage stress, and harmonic content can be achieved by properly tuning the converter parameters.
Rubber solutions were prepared and used for bonding wood pieces. The effect of the variation of c... more Rubber solutions were prepared and used for bonding wood pieces. The effect of the variation of chlorinated natural rubber (CNR) and phenolformaldehyde (PF) resin in the adhesive solutions on lap shear strength was determined. Natural rubber and neoprene-based adhesive solutions were compared for their lap shear strength. The storage stability of the adhesive prepared was determined. The change in lap shear strength before and after being placed in cold water, hot water, acid, and alkali was tested. The bonding character of these adhesives was compared with different commercially available solution adhesives. The room-temperature aging resistance of wood joints was also determined. In all the studies, the adhesive prepared in the laboratory was found to be superior compared to the commercial adhesives.
Abstract-Natural rubber latex-based adhesives were prepared for wood-to-wood bonding. The effects... more Abstract-Natural rubber latex-based adhesives were prepared for wood-to-wood bonding. The effects of prevulcanization, and varying amounts of ammonium caseinate, carboxymethyl cellulose, cooked starch, and phenol formaldehyde resin on adhesion were studied. The ...
International Journal of Polymeric Materials, 1996
... Use of amine terminated liquid natural rubber as a plasticiser in filled NR and NBR compounds... more ... Use of amine terminated liquid natural rubber as a plasticiser in filled NR and NBR compounds. Auteur(s) / Author(s). SRILATHAKUTTY R. (1) ; JOHN N. (1) ; JOSEPH R. (1) ; GEORGE KE (1) ; Affiliation(s) du ou des auteurs / Author(s) Affiliation(s). (1) Dept. ...
Melt blending of thermoplastic polyurethane (TPU) with polyolefins (PO’s) can lower the cost and ... more Melt blending of thermoplastic polyurethane (TPU) with polyolefins (PO’s) can lower the cost and improve mechanical and chemical properties. Since TPU and PO’s are completely immiscible polymers, property enhancement cannot be attained. Effect of incorporation of polypropylene copolymer (PPCP), TPU-g-MA, TPU-g- AA as compatibiliser on the miscibility of the blends and effect of clay filler on the mechanical properties were studied. Blends were produced by melt mixing using a single screw extruder. Mechanical and morphological properties were studied. The results show that the blend of thermoplastic polyurethane (TPU)/PO’s with suitable compatibiliser and clay gives excellent performance in all aspects.
Thermoplastic Polyurethane (TPU) is a highly versatile material with superior physical properties... more Thermoplastic Polyurethane (TPU) is a highly versatile material with superior physical properties but high cost. Melt blending of TPU with Polyolefins (PO) can lower the cost and improve mechanical and chemical properties. Since TPU and PO are completely immiscible polymers, property enhancement cannot be attained. Effect of incorporation of Polypropylene Copolymer (PPCP) as compatibilizer on the miscibility of the blends and effect of calcium carbonate as filler to enhance the mechanical properties were studied. Blends were produced by melt mixing using a single screw extruder. Miscibility studies were done using Scanning Electron Microscope (SEM) and thermal characteristics were determined using Differential Scanning Calorimeter (DSC). Mechanical properties like tensile strength, impact strength, flexural strength and hardness were also studied using Universal Testing Machine (UTM). The results show that the blend having 20% loading of polyurethane (PU) with suitable compatibilizers and calcium carbonate gives excellent performance in all aspects.
Blends of Nylon-66/ABS were prepared in various proportions. ABS was chemically modified using et... more Blends of Nylon-66/ABS were prepared in various proportions. ABS was chemically modified using ethylene glycol, ethylene diamine and acrylamide. Butadiene region of ABS acted as site for modification reactions, irradiated by UV using UV initiator in UV reactor. m-ABS were characterized using FTIR confirming chemical functionalization. m-ABS blended with Nylon-66 and results compared with original ABS/N-66 blends. Physical, mechanical, chemical,
International Journal of Polymeric Materials, 2011
Acrylonitrile butadiene styrene (ABS) was grafted using long chain molecules like oleic acid and ... more Acrylonitrile butadiene styrene (ABS) was grafted using long chain molecules like oleic acid and dodecylamine. Grafting took place at the butadiene region of ABS. Grafted ABS (g-ABS) polymers were characterized using FTIR and blended with nylon-66 in various proportions. Physical, chemical, mechanical and thermal properties of the blends were analyzed. A physical blending technique was followed between nylon-66 and ABS
International Journal of Polymeric Materials, 2011
Acrylonitrile butadiene styrene (ABS) was grafted using long chain molecules like oleic acid and ... more Acrylonitrile butadiene styrene (ABS) was grafted using long chain molecules like oleic acid and dodecylamine. Grafting took place at the butadiene region of ABS. Grafted ABS (g-ABS) polymers were characterized using FTIR and blended with nylon-66 in various proportions. Physical, chemical, mechanical and thermal properties of the blends were analyzed. A physical blending technique was followed between nylon-66 and ABS
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