The Experts below are selected from a list of 318 Experts worldwide ranked by ideXlab platform
Vijay Kumar Sinha - One of the best experts on this subject based on the ideXlab platform.
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Bio-acrylic Polyols for two pack polyurethane coating
Journal of Scientific & Industrial Research, 2004Co-Authors: J. V. Patel, Sandip D. Desai, Vijay Kumar SinhaAbstract:The feasibility of starch and non-edible oil in liquid polyester Polyol synthesis and their modification by using acrylic and vinyl monomers is studied. Polyurethane coatings are formulated by reacting synthesized Polyolswith aromatic isocyanate adduct. Performance properties of oil and bio-acrylic Polyol based polyurethane coatings are compared. It is found that acrylation of Polyol improves the overall performance of the coating. Synthesized Polyols and polyurethane are characterized by Fourier transform infrared spectroscopy (FTIR), Gel permeation chromatography (GPC), and Differential scanning calorimetry (DSC).
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Biomaterial Based Polyurethane Adhesive for Bonding Rubber and Wood Joints
Journal of Polymer Research, 2003Co-Authors: Sandip D. Desai, Anurag L. Emanuel, Vijay Kumar SinhaAbstract:An intermediate compound for synthesizing polyester Polyol was prepared from glycosylation of potato starch by reacting it with ethylene glycol in presence of sulphuric acid. Glycol glycoside thus prepared was characterized by HPLC and FTIR. This polyhydroxy compound was replaced in varying amounts with trimethylolpropane for polyester Polyol synthesis. Sebacic acid was used as dicarboxylic acid along with castor oil for polyester Polyol formulation. Polyols were reacted with toluene 2,4-diisocyanate adduct for polyurethane formation. Polyester Polyol and polyurethane were characterized by FTIR. Polyurethane was utilized for bonding wood as well as rubber joints. Bond strength was measured by means of lap shear strength and peel strength for wood and rubber joints, respectively. Chemical resistance of polyurethane adhesive was also evaluated.
Moyeenuddin Ahmad Sawpan - One of the best experts on this subject based on the ideXlab platform.
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Polyurethanes from vegetable oils and applications: a review
Journal of Polymer Research, 2018Co-Authors: Moyeenuddin Ahmad SawpanAbstract:Among the various polymers, polyurethanes are likely the most versatile specialty polymers. These polymers are widely used in many applications such as foams, coatings, insulations, adhesives, paints and upholstery. Similar to many polymers, polyurethanes relies on petrochemicals as raw materials for its major components. Indeed, nowadays many researches have focused to replace petroleum-based resources with renewable ones to improve polyurethanes sustainability. Polyurethanes are synthesized by polymerization reactions between isocyanates and Polyols. Only a few isocyanates are commonly used in polyurethane industries, while a variety of Polyols are available. Renewable materials such as vegetable oils are promising raw materials for the manufacture of polyurethane components such as Polyols. Vegetable oils are triglycerides which are the esterification product of glycerol with three fatty acids. Several highly reactive sites including carbon-carbon double bond, allylic position and ester group in triglycerides and fatty acids open the opportunities for various chemical modifications for new Polyol with different structures and functionalities. Different methods such as are epoxidation, ozonolysis, hydroformylation and metathesis have been widely studied to synthesise bio-Polyol from vegetable oil for new polyurethanes, which depend on triglyceride and isocyanate reagents used. The incorporation of a vegetable oil moiety can enhance thermal stability and mechanical strength of polyurethanes. Similar to bio-Polyol, the development of renewable resource based bio-isocyanates is also gained attention to produce entirely bio-polyurethanes. This article comprehensively reviews recent developments in the preparation of renewable resource based Polyols and isocyanates for producing polyurethanes and applications.
S K Nayak - One of the best experts on this subject based on the ideXlab platform.
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synthesis and characterizations of sustainable polyester Polyols from non edible vegetable oils thermal and structural evaluation
Journal of Cleaner Production, 2017Co-Authors: S Jayavani, S Sunanda, T O Varghese, S K NayakAbstract:Abstract Vegetable oils are extensively used as a renewable raw material for the synthesis of polymers. These oils are transformed into Polyol by different techniques. Among these, glycerolysis is an eco-friendly and widely used method for the production of Polyol. In this process, solvent free glycerolysis of two non-edible vegetable oils, such as Chaulmoogra oil (C-Oil) and Alexandrian Laurel seed oil (A-Oil) was performed. An environment-friendly heterogeneous base catalyst, CaO was used for the transesterification reaction. The physico-chemical properties of the oils and bio-Polyols (C-Polyol and A-Polyol), such as hydroxyl number, acid number, and density were determined. The hydroxyl value was found to be 189 and 200 mg KOH/g for C-Polyol and A-Polyol, respectively. The acid number of the oils was reduced after the glycerolysis. The formation of Polyols was confirmed by Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance spectroscopy ( 1 H and 13 CNMR), and Gel Permeation Chromatography (GPC). Thermal characteristics of vegetable oils and the synthesized bio-Polyol were assessed by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). It was found that the synthesized Polyols can be used for the production of biobased polymers, explicitly polyurethanes, polyesters, and epoxy.
Zoran S Petrovic - One of the best experts on this subject based on the ideXlab platform.
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Polyols and Polyurethanes from Crude Algal Oil
Journal of the American Oil Chemists' Society, 2013Co-Authors: Zoran S Petrovic, Olivera Bilić, Ivan Javni, Alisa Zlatanic, Jelena Milić, Mihail Ionescu, Jian Hong, Darin DegrusonAbstract:The composition of crude algal oil was analyzed and determined by several methods. Oil was converted to Polyols by ozonolysis, epoxidation, and hydroformylation. Ozonolysis gave a Polyol with lighter color but a low OH number and was unsuitable for polyurethane applications. Epoxidation also improved the color and gave a Polyol with an OH number around 150 mg KOH/g, which with diphenylmethane diisocyanate gave a homogeneous, rubbery, transparent sheet. Desirable rigid foams were prepared with the addition of water to the formulation. Hydroformylation was carried out successfully giving an OH number of about 150 mg KOH/g, but the Polyol was black. Casting the polyurethane sheet was difficult due to the very high reactivity of the Polyol. Polyurethane foam of lower quality than from epoxidation Polyol was obtained. More work on optimization of the foaming system would improve the foam. Crude algal oil is a viable starting material for the production of Polyols. Better results would be obtained from refined algal oils.
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Structure and properties of polyurethanes prepared from triglyceride Polyols by ozonolysis.
Biomacromolecules, 2005Co-Authors: Zoran S Petrovic, Wei Zhang, Ivan JavniAbstract:Ozonolysis was used to obtain Polyols with terminal primary hydroxyl groups and different functionalities from trilinolein (or triolein), low-saturation canola oil, and soybean oil. The functionality of the model Polyol from triolein (trilinolein) was 3.0 and that of soy Polyol was 2.5, due to the presence of unreactive saturated fatty acids, while canola gave a Polyol with a functionality of 2.8. All Polyols exhibited a high tendency to crystallize at room temperature. The resulting waxes had melting points comparable to that of paraffin and very low viscosities in the liquid state. The Polyols were cross-linked using 4,4‘-methylenebis(phenyl isocyanate) to give polyurethanes. Glass transitions (Tg) for the model-, canola-, and soy-based polyurethanes were 53, 36, and 22 °C, respectively. The about 30 °C lower Tg of the soy-based polyurethane than that of the model polyurethane was the result not only of lower functionality but also of the presence of saturated fatty acids in the former. Polyurethane fro...
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effect of structure on properties of Polyols and polyurethanes based on different vegetable oils
Journal of Polymer Science Part B, 2004Co-Authors: Alisa Zlatanic, Charlene C Lava, Zoran S PetrovicAbstract:We synthesized six polyurethane networks from 4,4-diphenylmethane di- isocyanate and Polyols based on midoleic sunflower, canola, soybean, sunflower, corn, and linseed oils. The differences in network structures reflected differences in the composition of fatty acids and number of functional groups in vegetable oils and resulting Polyols. The number average molecular weights of Polyols were between 1120 and 1300 and the functionality varied from 3.0 for the midoleic sunflower Polyol to 5.2 for the linseed Polyol. The functionality of the other four Polyols was around 3.5. Canola, corn, soybean, and sunflower oils gave polyurethane resins of similar crosslink- ing density and similar glass transitions and mechanical properties despite somewhat different distribution of fatty acids. Linseed oil- based polyurethane had higher crosslinking density and higher mechanical properties, whereas midoleic sunflower oil gave softer polyurethanes characterized by lower Tg and lower strength but higher elongation at break. It appears that the differences in properties of polyurethane networks resulted primarily from different crosslinking densities and less from the position of reactive sites in the fatty acids. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 809 - 819, 2004
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structure and properties of polyurethanes based on halogenated and nonhalogenated soy Polyols
Journal of Polymer Science Part A, 2000Co-Authors: Zoran S Petrovic, Wei ZhangAbstract:Four Polyols were prepared by a ring opening of epoxidized soybean oil with HCl, HBr, methanol, and by hydrogenation. Two series of polyurethanes were prepared by reacting the Polyols with two commercial isocyanates: PAPI and Isonate 2143L. Generally, the properties of the two series were similar. The crosslinking density of the polyurethane networks was analyzed by swelling in toluene. Brominated Polyols and their corresponding polyurethanes had the highest densities, followed by the chlorinated, methoxylated, and hydrogenated samples. The polyurethanes with brominated and chlorinated Polyols had comparable glass transition and strength, somewhat higher than the polyurethane from methoxy containing Polyol, while the polyurethane from the hydrogenated Polyol had lower glass-transition and mechanical properties. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4062–4069, 2000
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structure and properties of halogenated and nonhalogenated soy based Polyols
Journal of Polymer Science Part A, 2000Co-Authors: Zoran S PetrovicAbstract:Four Polyols intended for application in polyurethanes were synthesized by oxirane ring opening in epoxidized soybean oil with hydrochloric acid, hydrobromic acid, methanol, and hydrogen. The structures of the Polyols were characterized by spectroscopic, chemical, and physical methods. The brominated Polyol had 4.1 hydroxy groups, whereas the other three Polyols had slightly lower functionality. The densities, viscosities, viscous-flow activation energies, and molecular weights of the Polyols decreased in the following order: brominated > chlorinated > methoxylated > hydrogenated. All the Polyols were crystalline solids below their melting temperature, displaying multiple melting peaks. The methoxylated Polyol was liquid at room temperature, whereas the other three were waxes. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3900–3910, 2000
Sandip D. Desai - One of the best experts on this subject based on the ideXlab platform.
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Bio-acrylic Polyols for two pack polyurethane coating
Journal of Scientific & Industrial Research, 2004Co-Authors: J. V. Patel, Sandip D. Desai, Vijay Kumar SinhaAbstract:The feasibility of starch and non-edible oil in liquid polyester Polyol synthesis and their modification by using acrylic and vinyl monomers is studied. Polyurethane coatings are formulated by reacting synthesized Polyolswith aromatic isocyanate adduct. Performance properties of oil and bio-acrylic Polyol based polyurethane coatings are compared. It is found that acrylation of Polyol improves the overall performance of the coating. Synthesized Polyols and polyurethane are characterized by Fourier transform infrared spectroscopy (FTIR), Gel permeation chromatography (GPC), and Differential scanning calorimetry (DSC).
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Biomaterial Based Polyurethane Adhesive for Bonding Rubber and Wood Joints
Journal of Polymer Research, 2003Co-Authors: Sandip D. Desai, Anurag L. Emanuel, Vijay Kumar SinhaAbstract:An intermediate compound for synthesizing polyester Polyol was prepared from glycosylation of potato starch by reacting it with ethylene glycol in presence of sulphuric acid. Glycol glycoside thus prepared was characterized by HPLC and FTIR. This polyhydroxy compound was replaced in varying amounts with trimethylolpropane for polyester Polyol synthesis. Sebacic acid was used as dicarboxylic acid along with castor oil for polyester Polyol formulation. Polyols were reacted with toluene 2,4-diisocyanate adduct for polyurethane formation. Polyester Polyol and polyurethane were characterized by FTIR. Polyurethane was utilized for bonding wood as well as rubber joints. Bond strength was measured by means of lap shear strength and peel strength for wood and rubber joints, respectively. Chemical resistance of polyurethane adhesive was also evaluated.
