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John C. Mackie - One of the best experts on this subject based on the ideXlab platform.
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Low temperature oxidation of Linseed Oil: a review
2012Co-Authors: Juita Bogdan Z Dlugogorski, Eric M. Kennedy, John C. MackieAbstract:This review analyses and summarises the previous investigations on the oxidation of Linseed Oil and the self-heating of cotton and other materials impregnated with the Oil. It discusses the composition and chemical structure of Linseed Oil, including its drying properties. The review describes several experimental methods used to test the propensity of the Oil to induce spontaneous heating and ignition of lignocellulosic materials soaked with the Oil. It covers the thermal ignition of the lignocellulosic substrates impregnated with the Oil and it critically evaluates the analytical methods applied to investigate the oxidation reactions of Linseed Oil. Initiation of radical chains by singlet oxygen (1?g), and their propagation underpin the mechanism of oxidation of Linseed Oil, leading to the self-heating and formation of volatile organic species and higher molecular weight compounds. The review also discusses the role of metal complexes of cobalt, iron and manganese in catalysing the oxidative drying of Linseed Oil, summarising some kinetic parameters such as the rate constants of the peroxidation reactions. With respect to fire safety, the classical theory of self-ignition does not account for radical and catalytic reactions and appears to offer limited insights into the autoignition of lignocellulosic materials soaked with Linseed Oil. New theoretical and numerical treatments of oxidation of such materials need to be developed. The self-ignition induced by Linseed Oil is predicated on the presence of both a metal catalyst and a lignocellulosic substrate, and the absence of any prior thermal treatment of the Oil, which destroys both peroxy radicals and singlet O2 sensitisers. An overview of peroxyl chemistry included in the article will be useful to those working in areas of fire science, paint drying, indoor air quality, biofuels and lipid oxidation.
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Linseed Oil and its Tendency to Self-Heat
Fire Safety Science, 2011Co-Authors: Juita, Bogdan Z. Dlugogorski, Eric M. Kennedy, John C. MackieAbstract:Several varieties of Linseed Oil are commercially available, and they have been used for many applications especially in decorative furniture finishing and as an Oil painting medium. The addition of metallic driers to the Linseed Oil is a common practice, as it improves the drying rate of the paint. Several cases of fires have been reported, often involving rags soaked with Linseed Oil which have not been disposed of properly, and it is generally agreed that metal salts in the Linseed Oil play an important role in the spontaneous ignition of the Oil. This paper investigates several types of Linseed Oil sold in the market and their tendency to cause self-heating of cotton which has been impregnated with Linseed Oil obtained from various sources. Experiments were performed in two reactors; a plug flow reactor for measurement of gaseous oxidation products and in a batch system for the determination of metal composition in the Oil. Both plug flow and batch systems employ fifty percent of oxygen and nitrogen mixtures for several hours in each experiment. Emission of gaseous products during the reaction was quantified by micro gas chromatography (µGC), and identified by Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS). Oil samples from batch system were digested using microwave and the metal composition was determined by inductively coupled plasma-optical emission spectrometer (ICP-OES). BOiled Linseed Oil is the most reactive Oil studied, followed by raw Linseed Oil and refined Linseed Oil which display similar reactivity, while the least reactive is stand Linseed Oil. ICP analysis confirmed the presence of cobalt in the bOiled Linseed Oil, which enhances the rate of oxidation reaction. For bOiled Linseed Oil, the cobalt in the Oil enhances the decomposition of peroxide resulting in the formation of various radicals which oxidize the Oil and the cotton wool, therefore the emission of gaseous products is higher during oxidation on the cotton wool support compared to glass wool and thus bOiled Linseed Oil has the highest tendency to self heat, especially if soaked on the cotton or rags. A kinetic model of peroxide formation and decomposition has been developed based on the experimental data. The reaction rate constant of the decomposition of peroxide has been found to be higher in the reaction using cobalt compared to that of without cobalt, confirming the role of cobalt in catalysing the peroxide decomposition reaction. Abstraction reactions by the radicals during oxidation lead to subsequent reactions which are generally very exothermic. Accumulation of sufficient heat, can ultimately lead to the temperature reaching the ignition point of the Oil and causing the self- heating and even ignition of the Oil.
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Oxidation reactions and spontaneous ignition of Linseed Oil
Proceedings of the Combustion Institute, 2011Co-Authors: Juita, Bogdan Z. Dlugogorski, Eric M. Kennedy, John C. MackieAbstract:The drying properties of Linseed Oil have been known since the 15th century, and exploited in artistic and industrial paints. Unfortunately, in the presence of metal salts, Linseed Oil applied to cotton fabric may induce self-heating and spontaneous ignition. The present study elucidates the chemical mechanisms which trigger both phenomena. Low-temperature oxidation of Linseed Oil and its active components, linoleic, linolenic and oleic acids in equimolar O2/N2 mixture has been investigated in a plug flow reactor housed inside an oven at an initial temperature between 60 and 100 °C, with the liquids impregnated onto the glass wool support. In particular, we have studied the effect of transition metal salts on the oxidation of Linseed Oil. We identified the gaseous species produced in the oxidation by means of Fourier transform infrared (FTIR) spectroscopy and gas chromatography-mass spectrometry (GC-MS), and quantified them by micro gas chromatography (μGC). FTIR spectroscopy indicated the presence of aldehydes and carboxylic acids, with identification of these species confirmed by GC-MS. We propose that in the presence of a metal catalyst, the oxidation process involves the formation of metal-dioxygen (superoxide) adducts. The catalytic effect of a metal cation depends on its ability to form superoxide. Cobalt(II) is the most effective catalyst among other transition metal salts, followed by manganese(II) and iron(II). In the absence of a catalyst, we found the Oil samples to undergo a slower autoxidation process, probably associated with cross-linking or polymerisation together with partial fragmentation to form the observed low molecular weight products.
Patit Paban Kundu - One of the best experts on this subject based on the ideXlab platform.
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Swelling Kinetics of Linseed Oil-Based Polymers
Journal of Applied Polymer Science, 2009Co-Authors: Vinay Sharma, J. S. Banait, Patit Paban KunduAbstract:Kinetics of swelling and sorption behavior of copolymers (based on Linseed Oil, styrene, divinylben- zene, and acrylic acid via cationic and thermal polymer- ization) is studied in tetrahydrofuran (THF) at different temperatures. The values of n in the transport equation are found to be below 0.4, showing non-Fickian or pseudo-Fickian transport in the polymers. The depend- ence of diffusion coefficient on the composition and temperature has also been studied for the Linseed Oil- based polymers. The diffusion coefficient in cationic samples decreases with an increase in the Oil contents in the samples. In case of thermal samples, the diffusion coefficient first increases up to 30% Oil contents and then decreases. The diffusion coefficient decreases with an increase in temperature for all of the Linseed Oil poly- mer samples. The sorption coefficient increases with an increase in the Oil contents for all samples. The crosslink density (calculated from the THF swelling) ranges
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Spectroscopic characterization of Linseed Oil based polymer nano-composites
Polymer Testing, 2008Co-Authors: Vinay Sharma, J. S. Banait, Patit Paban KunduAbstract:1 H NMR abstract Conjugated Linseed Oil based nano-composites from thermal polymerization have been investigated quantitatively through 1 H NMR and FTIR spectroscopic techniques. The solubility of samples measured by soxhlet extraction ranges from 28 to 55% for varying Linseed Oil content (30-70%) and 28 to 43% for the samples with varying montmorillonite clay content (0-10%). The content of grafted Linseed Oil calculated from 1 H NMR results ranges from 2 to 19% with varying Oil content (30-70%) and 7 to 22% with varying clay content (0-10%). The FTIR results show variation in grafted Linseed Oil content from 2 to 19% with varying Oil content (30-70%) and 6 to 23% with varying clay content (0-10%). The clay embedded in the polymer matrix, calculated from FTIR results, ranges from 3 to 5% with varying Oil content (30-70%) and 0 to 8% with varying clay content (0-10%).
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Spectroscopic Characterization of Linseed Oil Based Polymers
Industrial & Engineering Chemistry Research, 2008Co-Authors: Vinay Sharma, J. S. Banait, Patit Paban KunduAbstract:Linseed Oil based polymers from cationic and thermal polymerizations have been investigated quantitatively through 1H NMR and FTIR spectroscopic analysis. The solubility of the samples ranges from 22 to 37% for cationic samples and from 4.23 to 53% for thermal samples. The content of the grafted Linseed Oil calculated from 1H NMR results ranges from 22.9 to 43.0% and from 0 to 10% for cationic and thermal samples. The grafted Linseed Oil contents from FTIR are 18.2−45.4% and 0−10.7% for cationic and thermal samples. The values obtained through quantitative 1H NMR and FTIR spectroscopic analysis methods are consistent and can be applied to other polymers also.
A Winiarska - One of the best experts on this subject based on the ideXlab platform.
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comparative studies of oxidative stability of Linseed Oil
Thermochimica Acta, 2001Co-Authors: E Rudnik, A Szczucinska, H Gwardiak, A Szulc, A WiniarskaAbstract:Abstract The oxidative stability of Linseed Oil was studied using classical method based on determination of peroxide value (PV), the Rancimat method based on conductometric measurements and thermoanalytical methods, i.e. the differential scanning calorimetry (DSC) and thermogravimetry (TG) in oxygen atmosphere. The onset temperatures Tonset,DSC and Tonset,TG were determined from dynamical DSC and TG curves, respectively. From isothermal DSC curves times tonset were determined. The effect of two antioxidants was also studied. An antioxidant blend containing α-tocopherol, ascorbyl palmitate, citric acid, ascorbic acid, and ethoxylated ethylene glycol proved more effective than butylated hydroxy anisole for protection of Linseed Oil against process, in good agreement with results obtained by the classical titration and the Rancimat methods.
C.j. Abraham - One of the best experts on this subject based on the ideXlab platform.
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A solution to spontaneous combustion in Linseed Oil formulations
Polymer Degradation and Stability, 1996Co-Authors: C.j. AbrahamAbstract:Abstract Linseed Oil, a common ingredient in varnishes and Oil-based house paints, has an affinity for combining with oxygen. When the Oil oxidizes in air, sufficient heat is liberated to ignite whatever was used to apply the Linseed Oil formulation. Studies reproducing fires that have the capability of destroying homes and buildings and which have been captured on film demonstrate this phenomenon. Although Linseed Oil has excellent drying Oil qualities, unfortunately it causes fires to occur in materials (particularly fabrics) with which it comes in contact. This process of spontaneous combustion has been known to fire investigators for almost 200 years. The author has created a chemical solution which eliminates spontaneous combustion and causes the applicators used for Linseed Oil formulations to become flame retardant. Previous publications have espoused changes in the concentrations of the oleic Oil, linoleic and linolenic acids. Recommendations have also been made to create viable warnings and instructions placing the user on notice of the inherent dangers of spontaneous combustion. The author's patented solution to the problem eliminates any additional processing of the Linseed Oil and the use of warnings for either temporary or permanent storage of the applicators. This solution is applicable to all varnish and Oil-based house paint formulations containing Linseed Oil.
Vinay Sharma - One of the best experts on this subject based on the ideXlab platform.
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Swelling Kinetics of Linseed Oil-Based Polymers
Journal of Applied Polymer Science, 2009Co-Authors: Vinay Sharma, J. S. Banait, Patit Paban KunduAbstract:Kinetics of swelling and sorption behavior of copolymers (based on Linseed Oil, styrene, divinylben- zene, and acrylic acid via cationic and thermal polymer- ization) is studied in tetrahydrofuran (THF) at different temperatures. The values of n in the transport equation are found to be below 0.4, showing non-Fickian or pseudo-Fickian transport in the polymers. The depend- ence of diffusion coefficient on the composition and temperature has also been studied for the Linseed Oil- based polymers. The diffusion coefficient in cationic samples decreases with an increase in the Oil contents in the samples. In case of thermal samples, the diffusion coefficient first increases up to 30% Oil contents and then decreases. The diffusion coefficient decreases with an increase in temperature for all of the Linseed Oil poly- mer samples. The sorption coefficient increases with an increase in the Oil contents for all samples. The crosslink density (calculated from the THF swelling) ranges
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Spectroscopic characterization of Linseed Oil based polymer nano-composites
Polymer Testing, 2008Co-Authors: Vinay Sharma, J. S. Banait, Patit Paban KunduAbstract:1 H NMR abstract Conjugated Linseed Oil based nano-composites from thermal polymerization have been investigated quantitatively through 1 H NMR and FTIR spectroscopic techniques. The solubility of samples measured by soxhlet extraction ranges from 28 to 55% for varying Linseed Oil content (30-70%) and 28 to 43% for the samples with varying montmorillonite clay content (0-10%). The content of grafted Linseed Oil calculated from 1 H NMR results ranges from 2 to 19% with varying Oil content (30-70%) and 7 to 22% with varying clay content (0-10%). The FTIR results show variation in grafted Linseed Oil content from 2 to 19% with varying Oil content (30-70%) and 6 to 23% with varying clay content (0-10%). The clay embedded in the polymer matrix, calculated from FTIR results, ranges from 3 to 5% with varying Oil content (30-70%) and 0 to 8% with varying clay content (0-10%).
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Spectroscopic Characterization of Linseed Oil Based Polymers
Industrial & Engineering Chemistry Research, 2008Co-Authors: Vinay Sharma, J. S. Banait, Patit Paban KunduAbstract:Linseed Oil based polymers from cationic and thermal polymerizations have been investigated quantitatively through 1H NMR and FTIR spectroscopic analysis. The solubility of the samples ranges from 22 to 37% for cationic samples and from 4.23 to 53% for thermal samples. The content of the grafted Linseed Oil calculated from 1H NMR results ranges from 22.9 to 43.0% and from 0 to 10% for cationic and thermal samples. The grafted Linseed Oil contents from FTIR are 18.2−45.4% and 0−10.7% for cationic and thermal samples. The values obtained through quantitative 1H NMR and FTIR spectroscopic analysis methods are consistent and can be applied to other polymers also.