Bio-oils obtained from southern yellow pine biomass from two thermochemical conversion processes,... more Bio-oils obtained from southern yellow pine biomass from two thermochemical conversion processes, fast pyrolysis (FP) and hydrothermal liquefaction (HTL), were investigated. The effects of FP and HTL on the physical and chemical properties of the bio-oils were characterized. The HTL and FP bio-oil yields were 67 and 36 wt%, respectively. The results indicated that the physical properties of the HTL bio-oil and FP bio-oil were similar; however, there were variations in the composition of the bio-oils from the same biomass. The pH values of the FP and HTL bio-oils were 2.3 and 2.8, respectively. From the GC-MS (gas chromatography–mass spectrometry) analysis, esterified chemical compounds were prevalent in the HTL bio-oil, while phenols and phenolic derivatives were found in both bio-oils. The P-NMR (phosphorous nuclear magnetic resonance) analysis of the bio-oils further revealed that both FP and HTL bio-oils are rich in phenolic OH and aliphatic OH functionalities, which could serve ...
Directed by Yehia El Mogahzy This study focused on determining ways to detect identity theft of c... more Directed by Yehia El Mogahzy This study focused on determining ways to detect identity theft of cotton fibers through developing identification tests from fibers to end products. Cotton types examined in this study include: Extra-Long Staple cotton fibers such as Giza cotton, Supima cotton, and Chinese cotton, and Medium-Staple cotton such as American Upland cotton. Tests used to identify different cotton fiber type in the raw form included (1) standard methods, and (2) non-standard methods. Standard methods were primarily common fiber testing methods using the High-Volume Instrument (HVI) and the Advanced Fiber Information System (AFIS). These two systems were developed by Uster ® Technologies and they are widely used all over the world. These systems provide values of common fiber properties such as fiber length, Micronaire, fiber strength, color, maturity, and trash content (HVI), and fiber length, fineness, neps, maturity, and trash (AFIS). Using the values of these properties, one can easily distinguish between major vi categories of fiber types. For example, Extra-Long Staple cotton fibers (ELS) will have longer, finer, stronger, and more mature fibers than regular (Upland-like) cotton fibers. Non-standard methods that have never been used for cotton fiber identification were also developed and used. These include: Dyeing Test, Viscosity Test, and Sonic Test. Among these tests, viscosity and sonic modulus seem to provide distinguished differences between different cotton types. The study also dealt with two basic textile end products, namely: bed sheets and knit shirts to examine whether it is possible to identify different cotton fibers through their performances in the end products. This type of analysis showed that different cotton types can indeed have different effects on end product performance through which the identity of fiber can be traced back to its type and sources.
Epoxy resins (ERs) are one of the most versatile thermoset polymers which are widely used in vari... more Epoxy resins (ERs) are one of the most versatile thermoset polymers which are widely used in variety of applications from electrical and electronics (insulation and circuit boards) to construction and civil engineering works (coating of concrete floors), automotive (structural glue), and aircraft (carbon fiber reinforced composites) industries due to their superior properties such as toughness, mechanical strength, flexibility, chemical and thermal resistance and adhesion. The global epoxy production is projected to be 3 million tons by 2017 with a market size of USD 21.5 billion. Today epoxy and other plastic production processes rely on petroleumbased chemicals. Current petroleum use is large and creates significant problems such as air pollution, promotion of the greenhouse effect, and depletion of petroleum reserves. Therefore, environmental concerns, as well as instability in the petrochemical market, have recently increased in using more sustainable and renewable chemical resources. Bio-oil is a liquefied biomass produced by decomposition of lignocellulosic biomass through thermomechanical liquefaction processes, and it could be used as a biopolyol to synthesize bio-based epoxy resin due to its high hydroxyl number (OHN). The main hypothesis was that the reaction behavior and the consequent physical, mechanical, and thermal properties of resulting epoxy resin depend on the interaction between OH group availability in bio-oil and epoxy group in epichlorohydrin Therefore, the objectives of this dissertation were to (i) produce a high quality bio-oil via thermomechanical liquefaction of lignocellulosic biomass, (ii) I would like to start expressing my sincere gratitude to my major advisor, Dr. Brian K. Via, for giving me the opportunity to pursue a doctorate degree. This work would not have been possible without his guidance and help. I would also thank to my dissertation committee, Dr. Sushil Adhikari, Dr. Maria Auad and Dr. Gisela Buschle-Diller, for their support, encouragement and help. Special thanks to Dr. Mario Eden for accepting to be the outside reader of my dissertation, and giving me the opportunity to be a member of NSF-IGERT team. I deeply appreciate the NSF-IGERT team for their financial support for my studies. I would like to thank Forest Product Development Center at Auburn University for providing me a welcoming environment. I must also recognize my friends in Auburn for their continues motivation. Finally, I would like to express my deepest gratitude to my dear family, my mother Nahide Celikbag, and sisters Semanur Ekinci and Esmanur Nazli, for their unconditional love and support. I would like to dedicate this dissertation to my beloved father, Huseyin Celikbag (1955-2001).
A practical and convenient approach for making paraffin wax microspheres with a melt dispersion t... more A practical and convenient approach for making paraffin wax microspheres with a melt dispersion technique was reported in this study. Surfactants were melted in water by water bath and then added to a flask after the wax was completely melted with stirring. Paraffin wax microspheres were generated by cooling. The obtained microspheres exhibited uniform diameters in the range of 10-60 μm observed with a scanning electrical microscope and were mainly dependent on the surfactant ratio. Encapsulated microcrystalline cellulose particles with the previously mentioned conditions were also generated and demonstrated the possibility of encapsulating microcrystalline cellulose with some acceptable agglomeration, although some encapsulated individually. Encapsulation of cellulose could be beneficial if agglomeration could be minimized and the encapsulated microcapsules could be dispersed during blending for wood composites manufacture.
A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrotherm... more A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrothermal liquefaction of loblolly pine and utilized as a biopolyol in the synthesis of bio-oil-based epoxy resin (BOBER) for the first time. Hydroxyl groups in bio-oil were analyzed by quantitative 31P NMR. It was found that not only does the total hydroxyl number of bio-oil influence the yield and epoxy equivalent weight of BOBER, but also the distribution of hydroxyl groups within bio-oil (aliphatic, phenolic, and acidic OH) played an important role in the determination of the optimum amount of catalyst in the synthesis of BOBER. Differential scanning calorimetry analysis proved the self-curing phenomena of BOBER, and Fourier transform infrared spectroscopy suggested that etherification reaction was the dominate reaction during the self-curing. Glass transition temperature, cross-linking density, and the storage modulus of self-cured BOBER were calculated using a dynamic mechanical analyzer.
Loblolly pine was liquefied with ethylene glycol at 100, 150, 200 and 250 °C in order to analyze ... more Loblolly pine was liquefied with ethylene glycol at 100, 150, 200 and 250 °C in order to analyze the effect of liquefaction temperature on hydroxyl groups of bio-oil, and to determine the source and variation of hydroxyl groups. The optimum temperature was found to be 150-200 °C. Hydroxyl number (OHN) of the bio-oil was ranged from 632 to 1430 mg KOH/g. GC-MS analysis showed that 70-90% of OHN was generated from unreacted EG. (31)P NMR analysis showed that the majority of hydroxyl groups were aliphatic, and none of the bio-oil exhibited any detectable hydroxyl groups from phenolic sources. Finally, it was found that all bio-oils were stable in terms of OHN for 2 months when stored at -10 °C.
The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and... more The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and carbonyl groups in biopolyol produced from hydrothermal liquefaction of loblolly pine (Pinus spp.) carried out at 250, 300, 350 and 390°C for 30min. Water and water/ethanol mixture (1/1, wt/wt) were used as liquefying solvent in the HTL experiments. HTL in water and water/ethanol is donated as W-HTL and W/E-HTL, respectively. It was found that 300°C and water/ethanol solvent was the optimum liquefaction temperature and solvent, yielding up to 68.1wt.% bio-oil and 2.4wt.% solid residue. (31)P-NMR analysis showed that biopolyol produced by W-HTL was rich in phenolic OH while W/E-HTL produced more aliphatic OH rich biopolyols. Moreover, biopolyols with higher hydroxyl concentration were produced by W/E-HTL. Carbonyl groups were analyzed by (19)F-NMR, which showed that ethanol reduced the concentration of carbonyl groups.
The objective of this study was to make a comparative analysis of the effect of formic and acetic... more The objective of this study was to make a comparative analysis of the effect of formic and acetic acids as oxygen carriers on the epoxidation of soybean oil used with hydrogen peroxide as the oxygen donor. Comparative analysis between the use of formic acid (FA) and acetic acid (AA) was studied to obtain the most effective oxygen carrier that yielded high oxirane oxygen contents (OOC). The epoxidation reaction was carried out using a stoichiometric ratio of 1:0.5:1, 1:0.5:0.5, and 1:0.5:2 of soybean oil: formic/acetic acid: hydrogen peroxide. The synthesis was performed at three reaction times (2, 4 and 6 h) at a constant temperature of 50°C. Samples prepared using FA and AA were characterized using ASTM D1652-11 and confirmed by Fourier transform infrared (FTIR) spectroscopy. The result of this study proved FA to be an effective oxygen carrier compared to that of AA based on the high OOC and percent yield achieved. The optimum epoxidized soybean oil (ESO) sample using FA was obtain...
Bio-based phenol-formaldehyde polymer (BioNovolac) was developed by reacting molar excess of bio-... more Bio-based phenol-formaldehyde polymer (BioNovolac) was developed by reacting molar excess of bio-oil/phenol with formaldehyde in acidic medium. Glycidyl 3,5-diglycidoxybenzoate (GDGB), was prepared by direct glycidylation of α-resorcylic acid (RA), a naturally occurring phenolic monomer. GDGB was crosslinked in the presence of BioNovolac by anionic polymerization. Fourier transform infrared spectroscopy (FTIR) confirmed the formation of semi-interpenetrating polymer networks. The glass transition temperature and moduli of biobased crosslinked systems were observed to increase with increasing GDGB content. Active chain density and mass retention measured by dynamic mechanical analysis (DMA) and Soxhlet extraction, respectively, indicated a high crosslink density of the cured networks. Scanning electron microscopy (SEM) images depicted the homogeneity of the bulk phase. The preparation of bio-based epoxy-novolac thermoset network resulted in reduced consumption of petroleum-based chemicals.
Surfactants and paraffin wax were used to coat microcrystalline cellulose to prevent cellulose ag... more Surfactants and paraffin wax were used to coat microcrystalline cellulose to prevent cellulose agglomeration during dispersion in this study. The coated particles exhibited similar lengths, but the area of coverage varied from little to complete coverage of the cellulose particles depending on the amount of surfactant and paraffin wax. The results demonstrate the possibility of coating micro-crystalline cellulose with a desired amount of surfactants and paraffin wax.
A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrotherm... more A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrothermal liquefaction of loblolly pine and utilized as a biopolyol in the synthesis of bio-oil-based epoxy resin (BOBER) for the first time. Hydroxyl groups in bio-oil were analyzed by quantitative 31 P NMR. It was found that not only does the total hydroxyl number of bio-oil influence the yield and epoxy equivalent weight of BOBER, but also the distribution of hydroxyl groups within bio-oil (aliphatic, phenolic, and acidic OH) played an important role in the determination of the optimum amount of catalyst in the synthesis of BOBER. Differential scanning calorimetry analysis proved the self-curing phenomena of BOBER, and Fourier transform infrared spectroscopy suggested that etherification reaction was the dominate reaction during the self-curing. Glass transition temperature, cross-linking density, and the storage modulus of self-cured BOBER were calculated using a dynamic mechanical analyzer.
The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and... more The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and carbonyl groups in biopolyol produced from hydrothermal liquefaction of loblolly pine (Pinus spp.) carried out at 250, 300, 350 and 390 °C for 30 min. Water and water/ethanol mixture (1/1, wt/wt) were used as liquefying solvent in the HTL experiments. HTL in water and water/ethanol is donated as W-HTL and W/E-HTL, respectively. It was found that 300 °C and water/ethanol solvent was the optimum liquefaction temperature and solvent, yielding up to 68.1 wt.% bio-oil and 2.4 wt.% solid residue. 31 P-NMR analysis showed that biopolyol produced by W-HTL was rich in phenolic OH while W/E-HTL produced more aliphatic OH rich biopolyols. Moreover, biopolyols with higher hydroxyl concentration were produced by W/E-HTL. Carbonyl groups were analyzed by 19 F-NMR, which showed that ethanol reduced the concentration of carbonyl groups.
Wood and fiber science: journal of the Society of Wood Science and Technology
A practical and convenient approach for making paraffin wax microspheres with a meltdispersion te... more A practical and convenient approach for making paraffin wax microspheres with a meltdispersion technique was reported in this study. Surfactants were melted in water by water bath and thenadded to a flask after the wax was completely melted with stirring. Paraffin wax microspheres weregenerated by cooling. The obtained microspheres exhibited uniform diameters in the range of 10-60 m mobserved with a scanning electrical microscope and were mainly dependent on the surfactant ratio.Encapsulated microcrystalline cellulose particles with the previously mentioned conditions were alsogenerated and demonstrated the possibility of encapsulating microcrystalline cellulose with some acceptableagglomeration, although some encapsulated individually. Encapsulation of cellulose could be beneficial if agglomeration could be minimized and the encapsulated microcapsules could be dispersed during blend-ing for wood composites manufacture
Surfactants and paraffin wax were used to coat microcrystalline cellulose to prevent cellulose ag... more Surfactants and paraffin wax were used to coat microcrystalline cellulose to prevent cellulose agglomeration during dispersion in this study. The coated particles exhibited similar lengths, but the area of coverage varied from little to complete coverage of the cellulose particles depending on the amount of surfactant and paraffin wax. The results demonstrate the possibility of coating micro-crystalline cellulose with a desired amount of surfactants and paraffin wax.
Bio-oils obtained from southern yellow pine biomass from two thermochemical conversion processes,... more Bio-oils obtained from southern yellow pine biomass from two thermochemical conversion processes, fast pyrolysis (FP) and hydrothermal liquefaction (HTL), were investigated. The effects of FP and HTL on the physical and chemical properties of the bio-oils were characterized. The HTL and FP bio-oil yields were 67 and 36 wt%, respectively. The results indicated that the physical properties of the HTL bio-oil and FP bio-oil were similar; however, there were variations in the composition of the bio-oils from the same biomass. The pH values of the FP and HTL bio-oils were 2.3 and 2.8, respectively. From the GC-MS (gas chromatography–mass spectrometry) analysis, esterified chemical compounds were prevalent in the HTL bio-oil, while phenols and phenolic derivatives were found in both bio-oils. The P-NMR (phosphorous nuclear magnetic resonance) analysis of the bio-oils further revealed that both FP and HTL bio-oils are rich in phenolic OH and aliphatic OH functionalities, which could serve ...
Directed by Yehia El Mogahzy This study focused on determining ways to detect identity theft of c... more Directed by Yehia El Mogahzy This study focused on determining ways to detect identity theft of cotton fibers through developing identification tests from fibers to end products. Cotton types examined in this study include: Extra-Long Staple cotton fibers such as Giza cotton, Supima cotton, and Chinese cotton, and Medium-Staple cotton such as American Upland cotton. Tests used to identify different cotton fiber type in the raw form included (1) standard methods, and (2) non-standard methods. Standard methods were primarily common fiber testing methods using the High-Volume Instrument (HVI) and the Advanced Fiber Information System (AFIS). These two systems were developed by Uster ® Technologies and they are widely used all over the world. These systems provide values of common fiber properties such as fiber length, Micronaire, fiber strength, color, maturity, and trash content (HVI), and fiber length, fineness, neps, maturity, and trash (AFIS). Using the values of these properties, one can easily distinguish between major vi categories of fiber types. For example, Extra-Long Staple cotton fibers (ELS) will have longer, finer, stronger, and more mature fibers than regular (Upland-like) cotton fibers. Non-standard methods that have never been used for cotton fiber identification were also developed and used. These include: Dyeing Test, Viscosity Test, and Sonic Test. Among these tests, viscosity and sonic modulus seem to provide distinguished differences between different cotton types. The study also dealt with two basic textile end products, namely: bed sheets and knit shirts to examine whether it is possible to identify different cotton fibers through their performances in the end products. This type of analysis showed that different cotton types can indeed have different effects on end product performance through which the identity of fiber can be traced back to its type and sources.
Epoxy resins (ERs) are one of the most versatile thermoset polymers which are widely used in vari... more Epoxy resins (ERs) are one of the most versatile thermoset polymers which are widely used in variety of applications from electrical and electronics (insulation and circuit boards) to construction and civil engineering works (coating of concrete floors), automotive (structural glue), and aircraft (carbon fiber reinforced composites) industries due to their superior properties such as toughness, mechanical strength, flexibility, chemical and thermal resistance and adhesion. The global epoxy production is projected to be 3 million tons by 2017 with a market size of USD 21.5 billion. Today epoxy and other plastic production processes rely on petroleumbased chemicals. Current petroleum use is large and creates significant problems such as air pollution, promotion of the greenhouse effect, and depletion of petroleum reserves. Therefore, environmental concerns, as well as instability in the petrochemical market, have recently increased in using more sustainable and renewable chemical resources. Bio-oil is a liquefied biomass produced by decomposition of lignocellulosic biomass through thermomechanical liquefaction processes, and it could be used as a biopolyol to synthesize bio-based epoxy resin due to its high hydroxyl number (OHN). The main hypothesis was that the reaction behavior and the consequent physical, mechanical, and thermal properties of resulting epoxy resin depend on the interaction between OH group availability in bio-oil and epoxy group in epichlorohydrin Therefore, the objectives of this dissertation were to (i) produce a high quality bio-oil via thermomechanical liquefaction of lignocellulosic biomass, (ii) I would like to start expressing my sincere gratitude to my major advisor, Dr. Brian K. Via, for giving me the opportunity to pursue a doctorate degree. This work would not have been possible without his guidance and help. I would also thank to my dissertation committee, Dr. Sushil Adhikari, Dr. Maria Auad and Dr. Gisela Buschle-Diller, for their support, encouragement and help. Special thanks to Dr. Mario Eden for accepting to be the outside reader of my dissertation, and giving me the opportunity to be a member of NSF-IGERT team. I deeply appreciate the NSF-IGERT team for their financial support for my studies. I would like to thank Forest Product Development Center at Auburn University for providing me a welcoming environment. I must also recognize my friends in Auburn for their continues motivation. Finally, I would like to express my deepest gratitude to my dear family, my mother Nahide Celikbag, and sisters Semanur Ekinci and Esmanur Nazli, for their unconditional love and support. I would like to dedicate this dissertation to my beloved father, Huseyin Celikbag (1955-2001).
A practical and convenient approach for making paraffin wax microspheres with a melt dispersion t... more A practical and convenient approach for making paraffin wax microspheres with a melt dispersion technique was reported in this study. Surfactants were melted in water by water bath and then added to a flask after the wax was completely melted with stirring. Paraffin wax microspheres were generated by cooling. The obtained microspheres exhibited uniform diameters in the range of 10-60 μm observed with a scanning electrical microscope and were mainly dependent on the surfactant ratio. Encapsulated microcrystalline cellulose particles with the previously mentioned conditions were also generated and demonstrated the possibility of encapsulating microcrystalline cellulose with some acceptable agglomeration, although some encapsulated individually. Encapsulation of cellulose could be beneficial if agglomeration could be minimized and the encapsulated microcapsules could be dispersed during blending for wood composites manufacture.
A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrotherm... more A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrothermal liquefaction of loblolly pine and utilized as a biopolyol in the synthesis of bio-oil-based epoxy resin (BOBER) for the first time. Hydroxyl groups in bio-oil were analyzed by quantitative 31P NMR. It was found that not only does the total hydroxyl number of bio-oil influence the yield and epoxy equivalent weight of BOBER, but also the distribution of hydroxyl groups within bio-oil (aliphatic, phenolic, and acidic OH) played an important role in the determination of the optimum amount of catalyst in the synthesis of BOBER. Differential scanning calorimetry analysis proved the self-curing phenomena of BOBER, and Fourier transform infrared spectroscopy suggested that etherification reaction was the dominate reaction during the self-curing. Glass transition temperature, cross-linking density, and the storage modulus of self-cured BOBER were calculated using a dynamic mechanical analyzer.
Loblolly pine was liquefied with ethylene glycol at 100, 150, 200 and 250 °C in order to analyze ... more Loblolly pine was liquefied with ethylene glycol at 100, 150, 200 and 250 °C in order to analyze the effect of liquefaction temperature on hydroxyl groups of bio-oil, and to determine the source and variation of hydroxyl groups. The optimum temperature was found to be 150-200 °C. Hydroxyl number (OHN) of the bio-oil was ranged from 632 to 1430 mg KOH/g. GC-MS analysis showed that 70-90% of OHN was generated from unreacted EG. (31)P NMR analysis showed that the majority of hydroxyl groups were aliphatic, and none of the bio-oil exhibited any detectable hydroxyl groups from phenolic sources. Finally, it was found that all bio-oils were stable in terms of OHN for 2 months when stored at -10 °C.
The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and... more The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and carbonyl groups in biopolyol produced from hydrothermal liquefaction of loblolly pine (Pinus spp.) carried out at 250, 300, 350 and 390°C for 30min. Water and water/ethanol mixture (1/1, wt/wt) were used as liquefying solvent in the HTL experiments. HTL in water and water/ethanol is donated as W-HTL and W/E-HTL, respectively. It was found that 300°C and water/ethanol solvent was the optimum liquefaction temperature and solvent, yielding up to 68.1wt.% bio-oil and 2.4wt.% solid residue. (31)P-NMR analysis showed that biopolyol produced by W-HTL was rich in phenolic OH while W/E-HTL produced more aliphatic OH rich biopolyols. Moreover, biopolyols with higher hydroxyl concentration were produced by W/E-HTL. Carbonyl groups were analyzed by (19)F-NMR, which showed that ethanol reduced the concentration of carbonyl groups.
The objective of this study was to make a comparative analysis of the effect of formic and acetic... more The objective of this study was to make a comparative analysis of the effect of formic and acetic acids as oxygen carriers on the epoxidation of soybean oil used with hydrogen peroxide as the oxygen donor. Comparative analysis between the use of formic acid (FA) and acetic acid (AA) was studied to obtain the most effective oxygen carrier that yielded high oxirane oxygen contents (OOC). The epoxidation reaction was carried out using a stoichiometric ratio of 1:0.5:1, 1:0.5:0.5, and 1:0.5:2 of soybean oil: formic/acetic acid: hydrogen peroxide. The synthesis was performed at three reaction times (2, 4 and 6 h) at a constant temperature of 50°C. Samples prepared using FA and AA were characterized using ASTM D1652-11 and confirmed by Fourier transform infrared (FTIR) spectroscopy. The result of this study proved FA to be an effective oxygen carrier compared to that of AA based on the high OOC and percent yield achieved. The optimum epoxidized soybean oil (ESO) sample using FA was obtain...
Bio-based phenol-formaldehyde polymer (BioNovolac) was developed by reacting molar excess of bio-... more Bio-based phenol-formaldehyde polymer (BioNovolac) was developed by reacting molar excess of bio-oil/phenol with formaldehyde in acidic medium. Glycidyl 3,5-diglycidoxybenzoate (GDGB), was prepared by direct glycidylation of α-resorcylic acid (RA), a naturally occurring phenolic monomer. GDGB was crosslinked in the presence of BioNovolac by anionic polymerization. Fourier transform infrared spectroscopy (FTIR) confirmed the formation of semi-interpenetrating polymer networks. The glass transition temperature and moduli of biobased crosslinked systems were observed to increase with increasing GDGB content. Active chain density and mass retention measured by dynamic mechanical analysis (DMA) and Soxhlet extraction, respectively, indicated a high crosslink density of the cured networks. Scanning electron microscopy (SEM) images depicted the homogeneity of the bulk phase. The preparation of bio-based epoxy-novolac thermoset network resulted in reduced consumption of petroleum-based chemicals.
Surfactants and paraffin wax were used to coat microcrystalline cellulose to prevent cellulose ag... more Surfactants and paraffin wax were used to coat microcrystalline cellulose to prevent cellulose agglomeration during dispersion in this study. The coated particles exhibited similar lengths, but the area of coverage varied from little to complete coverage of the cellulose particles depending on the amount of surfactant and paraffin wax. The results demonstrate the possibility of coating micro-crystalline cellulose with a desired amount of surfactants and paraffin wax.
A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrotherm... more A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrothermal liquefaction of loblolly pine and utilized as a biopolyol in the synthesis of bio-oil-based epoxy resin (BOBER) for the first time. Hydroxyl groups in bio-oil were analyzed by quantitative 31 P NMR. It was found that not only does the total hydroxyl number of bio-oil influence the yield and epoxy equivalent weight of BOBER, but also the distribution of hydroxyl groups within bio-oil (aliphatic, phenolic, and acidic OH) played an important role in the determination of the optimum amount of catalyst in the synthesis of BOBER. Differential scanning calorimetry analysis proved the self-curing phenomena of BOBER, and Fourier transform infrared spectroscopy suggested that etherification reaction was the dominate reaction during the self-curing. Glass transition temperature, cross-linking density, and the storage modulus of self-cured BOBER were calculated using a dynamic mechanical analyzer.
The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and... more The goal of this study was to investigate the role of ethanol and temperature on the hydroxyl and carbonyl groups in biopolyol produced from hydrothermal liquefaction of loblolly pine (Pinus spp.) carried out at 250, 300, 350 and 390 °C for 30 min. Water and water/ethanol mixture (1/1, wt/wt) were used as liquefying solvent in the HTL experiments. HTL in water and water/ethanol is donated as W-HTL and W/E-HTL, respectively. It was found that 300 °C and water/ethanol solvent was the optimum liquefaction temperature and solvent, yielding up to 68.1 wt.% bio-oil and 2.4 wt.% solid residue. 31 P-NMR analysis showed that biopolyol produced by W-HTL was rich in phenolic OH while W/E-HTL produced more aliphatic OH rich biopolyols. Moreover, biopolyols with higher hydroxyl concentration were produced by W/E-HTL. Carbonyl groups were analyzed by 19 F-NMR, which showed that ethanol reduced the concentration of carbonyl groups.
Wood and fiber science: journal of the Society of Wood Science and Technology
A practical and convenient approach for making paraffin wax microspheres with a meltdispersion te... more A practical and convenient approach for making paraffin wax microspheres with a meltdispersion technique was reported in this study. Surfactants were melted in water by water bath and thenadded to a flask after the wax was completely melted with stirring. Paraffin wax microspheres weregenerated by cooling. The obtained microspheres exhibited uniform diameters in the range of 10-60 m mobserved with a scanning electrical microscope and were mainly dependent on the surfactant ratio.Encapsulated microcrystalline cellulose particles with the previously mentioned conditions were alsogenerated and demonstrated the possibility of encapsulating microcrystalline cellulose with some acceptableagglomeration, although some encapsulated individually. Encapsulation of cellulose could be beneficial if agglomeration could be minimized and the encapsulated microcapsules could be dispersed during blend-ing for wood composites manufacture
Surfactants and paraffin wax were used to coat microcrystalline cellulose to prevent cellulose ag... more Surfactants and paraffin wax were used to coat microcrystalline cellulose to prevent cellulose agglomeration during dispersion in this study. The coated particles exhibited similar lengths, but the area of coverage varied from little to complete coverage of the cellulose particles depending on the amount of surfactant and paraffin wax. The results demonstrate the possibility of coating micro-crystalline cellulose with a desired amount of surfactants and paraffin wax.
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