The Experts below are selected from a list of 69 Experts worldwide ranked by ideXlab platform

Xiuzhi Susan Sun - One of the best experts on this subject based on the ideXlab platform.

  • solvent free acid catalyzed ring opening of Epoxidized oleochemicals using stearates stearic acid and its applications
    Journal of Agricultural and Food Chemistry, 2012
    Co-Authors: Byungjun Kollbe Ahn, Stefan Kraft, Xiuzhi Susan Sun
    Abstract:

    Toxic solvent and strong acid catalysts causing environmental issues have been mainly used for ring-opening of Epoxidized oleochemicals. Here, we demonstrated that magnesium stearate (Mg-stearate) was a high efficient catalyst for solvent-free ring-opening of Epoxidized Methyl Oleate, a model compound of midchain epoxide. Mg-stearate resulted in the highest yield (95%) and conversion rate (99%) toward midchain alkoxyesters under the same conditions (160 °C, 12 h) superior to other fatty acid derivatives such as a Lewis acid (lithium and sodium stearate) and Bronsted acid (stearic acid). Based on this chemical study, we synthesized biogrease and thermoplastic using Epoxidized soybean oil (ESO) and Mg-stearate via one-pot, solvent-free, and purification-free process. Mg-stearate played a significant role as a reactant for epoxide ring-opening and as a thickener when excess loading rate was used; viscosity increased from 1800 to 4500 Pa·s at 25 °C when ESO:Mg-stearate increased from 1:1 equiv to 1:2, then behaved like thermoplastics (T(g) = -27 °C, T(m) = 90 °C) with 1:4.

  • ring opening of Epoxidized Methyl Oleate using a novel acid functionalized iron nanoparticle catalyst
    Green Chemistry, 2012
    Co-Authors: Kollbe B Ahn, Hongwang Wang, Shona Robinson, Tej B Shrestha, Deryl L Troyer, Stefan H Bossmann, Xiuzhi Susan Sun
    Abstract:

    Hydroxyl soybean oils, also called soy polyols, are biobased chemicals designed to replace petroleum-based polyols mainly for polyurethane (PU) applications. Soy polyols are obtained by acid-catalyzed ring opening of expoxidized soybean oils or other Epoxidized plant oils by nucleophilic SN2 attack of methanol. Recyclable heterogeneous catalysts are preferred for the ring-opening reactions over non-recyclable homogeneous catalysts because they minimize environmental impact. The drawbacks of current solid catalysts such as SAC 13 and Amberlite 15 are low production yield and high energy consumption. Here, we demonstrate a greener synthetic pathway of soy polyols with low energy consumption and excellent atom economy and environment (E) factor by using novel sulfamic acid-functionalized iron (iron/iron oxide core shell) nanoparticles (NPs) as a heterogeneous catalyst. The excellent selectivity of the reaction with the recyclable NPs was confirmed by 1H NMR, 1H-1H COSY NMR, and ESI-MS comparable to non-recyclable H2SO4. The synthetic route with the NPs resulted in higher product yield (almost 100%) as H2SO4 at room temperature for 30 min over the SAC 13 (83% yield at 60 °C for 60 min) and Amberlite 15 (87% yield at 60 °C for 100 min). Life cycle assessment (LCA) revealed that the NP synthetic technology for soy polyol production is superior or equal to the competing routes (H2SO4, SAC 13, and Amberlite 15 methods) with respect to 9 environmental impacts (acidification potential, ozone depletion potential, smog formation potential, global warming potential, human toxicity by ingestion, human toxicity by inhalation, persistence, bioaccumulation, and abiotic resource depletion potential).

  • Solvent-Free Acid-Catalyzed Ring-Opening of Epoxidized Oleochemicals Using Stearates/Stearic Acid, and Its Applications
    2012
    Co-Authors: Byung-jun Kollbe Ahn, Stefan Kraft, Xiuzhi Susan Sun
    Abstract:

    Toxic solvent and strong acid catalysts causing environmental issues have been mainly used for ring-opening of Epoxidized oleochemicals. Here, we demonstrated that magnesium stearate (Mg-stearate) was a high efficient catalyst for solvent-free ring-opening of Epoxidized Methyl Oleate, a model compound of midchain epoxide. Mg-stearate resulted in the highest yield (95%) and conversion rate (99%) toward midchain alkoxyesters under the same conditions (160 °C, 12 h) superior to other fatty acid derivatives such as a Lewis acid (lithium and sodium stearate) and Brønsted acid (stearic acid). Based on this chemical study, we synthesized biogrease and thermoplastic using Epoxidized soybean oil (ESO) and Mg-stearate via one-pot, solvent-free, and purification-free process. Mg-stearate played a significant role as a reactant for epoxide ring-opening and as a thickener when excess loading rate was used; viscosity increased from 1800 to 4500 Pa·s at 25 °C when ESO:Mg-stearate increased from 1:1 equiv to 1:2, then behaved like thermoplastics (Tg = −27 °C, Tm = 90 °C) with 1:4

Stefan Kraft - One of the best experts on this subject based on the ideXlab platform.

  • solvent free acid catalyzed ring opening of Epoxidized oleochemicals using stearates stearic acid and its applications
    Journal of Agricultural and Food Chemistry, 2012
    Co-Authors: Byungjun Kollbe Ahn, Stefan Kraft, Xiuzhi Susan Sun
    Abstract:

    Toxic solvent and strong acid catalysts causing environmental issues have been mainly used for ring-opening of Epoxidized oleochemicals. Here, we demonstrated that magnesium stearate (Mg-stearate) was a high efficient catalyst for solvent-free ring-opening of Epoxidized Methyl Oleate, a model compound of midchain epoxide. Mg-stearate resulted in the highest yield (95%) and conversion rate (99%) toward midchain alkoxyesters under the same conditions (160 °C, 12 h) superior to other fatty acid derivatives such as a Lewis acid (lithium and sodium stearate) and Bronsted acid (stearic acid). Based on this chemical study, we synthesized biogrease and thermoplastic using Epoxidized soybean oil (ESO) and Mg-stearate via one-pot, solvent-free, and purification-free process. Mg-stearate played a significant role as a reactant for epoxide ring-opening and as a thickener when excess loading rate was used; viscosity increased from 1800 to 4500 Pa·s at 25 °C when ESO:Mg-stearate increased from 1:1 equiv to 1:2, then behaved like thermoplastics (T(g) = -27 °C, T(m) = 90 °C) with 1:4.

  • Synthesis and characterization of amphiphilic reduced graphene oxide with Epoxidized Methyl Oleate
    Advanced Materials, 2012
    Co-Authors: B. Kollbe Ahn, Jonggeun Sung, Myles Ikenberry, Keith Hohn, T. S. Sreeprasad, Namhoon Kim, Phong Nguyen, Nihar Mohanty, Yonghui Li, Stefan Kraft
    Abstract:

    Amphiphilic reduced graphene oxide is obtained by oleo-functionalization with Epoxidized Methyl Oleate (renewable feedstock) using a green process. The excellent diverse solvent-dispersivity of the oleo-reduced amphiphilic graphene and its reduction chemistry are confirmed in this study. Oleo-reduction of amphiphilic graphene is amenable to industrially viable processes to produce future graphene-based polymer composites and systems.

  • Solvent-Free Acid-Catalyzed Ring-Opening of Epoxidized Oleochemicals Using Stearates/Stearic Acid, and Its Applications
    2012
    Co-Authors: Byung-jun Kollbe Ahn, Stefan Kraft, Xiuzhi Susan Sun
    Abstract:

    Toxic solvent and strong acid catalysts causing environmental issues have been mainly used for ring-opening of Epoxidized oleochemicals. Here, we demonstrated that magnesium stearate (Mg-stearate) was a high efficient catalyst for solvent-free ring-opening of Epoxidized Methyl Oleate, a model compound of midchain epoxide. Mg-stearate resulted in the highest yield (95%) and conversion rate (99%) toward midchain alkoxyesters under the same conditions (160 °C, 12 h) superior to other fatty acid derivatives such as a Lewis acid (lithium and sodium stearate) and Brønsted acid (stearic acid). Based on this chemical study, we synthesized biogrease and thermoplastic using Epoxidized soybean oil (ESO) and Mg-stearate via one-pot, solvent-free, and purification-free process. Mg-stearate played a significant role as a reactant for epoxide ring-opening and as a thickener when excess loading rate was used; viscosity increased from 1800 to 4500 Pa·s at 25 °C when ESO:Mg-stearate increased from 1:1 equiv to 1:2, then behaved like thermoplastics (Tg = −27 °C, Tm = 90 °C) with 1:4

Byungjun Kollbe Ahn - One of the best experts on this subject based on the ideXlab platform.

  • solvent free acid catalyzed ring opening of Epoxidized oleochemicals using stearates stearic acid and its applications
    Journal of Agricultural and Food Chemistry, 2012
    Co-Authors: Byungjun Kollbe Ahn, Stefan Kraft, Xiuzhi Susan Sun
    Abstract:

    Toxic solvent and strong acid catalysts causing environmental issues have been mainly used for ring-opening of Epoxidized oleochemicals. Here, we demonstrated that magnesium stearate (Mg-stearate) was a high efficient catalyst for solvent-free ring-opening of Epoxidized Methyl Oleate, a model compound of midchain epoxide. Mg-stearate resulted in the highest yield (95%) and conversion rate (99%) toward midchain alkoxyesters under the same conditions (160 °C, 12 h) superior to other fatty acid derivatives such as a Lewis acid (lithium and sodium stearate) and Bronsted acid (stearic acid). Based on this chemical study, we synthesized biogrease and thermoplastic using Epoxidized soybean oil (ESO) and Mg-stearate via one-pot, solvent-free, and purification-free process. Mg-stearate played a significant role as a reactant for epoxide ring-opening and as a thickener when excess loading rate was used; viscosity increased from 1800 to 4500 Pa·s at 25 °C when ESO:Mg-stearate increased from 1:1 equiv to 1:2, then behaved like thermoplastics (T(g) = -27 °C, T(m) = 90 °C) with 1:4.

Gerard Lligadas - One of the best experts on this subject based on the ideXlab platform.

  • biobased polyurethanes from polyether polyols obtained by ionic coordinative polymerization of Epoxidized Methyl Oleate
    Journal of Polymer Science Part A, 2010
    Co-Authors: E. Del Rio, Massimo Galia, Gerard Lligadas, Joan Carles Ronda, Virginia Cádiz
    Abstract:

    A series of poly(ether urethane) networks were synthesized from polyether polyols obtained by ionic-coordinative polymerization of Epoxidized Methyl Oleate (EMO) using 4,4′-Methylenebis(phenyl isocyanate) or l-lysine diisocyanate as coupling agents. Moreover, a variety of segmented poly(ether urethane) networks with different hard segment contents were obtained using 1,3-propanediol as the chain extender. The materials were characterized by differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical thermal analysis, and tensile properties. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010

  • vegetable oil based thermosetting polymers
    European Journal of Lipid Science and Technology, 2010
    Co-Authors: Marina Galià, Gerard Lligadas, Joan Carles Ronda, Lucas Montero De Espinosa, Virginia Cádiz
    Abstract:

    Vegetable oils are excellent renewable raw materials for thermosetting polymers. By the direct polymerization of triglyceride C=C, we obtained organic-inorganic hybrid materials with promising properties for optical applications by the hydrosilylation of alkenyl-terminated fatty acid derivatives. The presence of double bonds in triglycerides makes it possible to attach some functional groups through chemical modification, and we describe various chemical pathways for functionalizing triglycerides and fatty acids. Epoxidation is one of the most interesting chemical modifications that leads to Epoxidized vegetable oils. We report the preparation of biobased polyhedral oligomeric silsesquioxanes-nanocomposites from Epoxidized linseed oil. Moreover, we describe the preparation of a new family of Epoxidized Methyl Oleate-based polyether polyols, which were used in the synthesis of polyurethanes with specific applications: silicon-containing polyurethanes with enhanced flame-retardant properties and polyurethane networks with potential applications in biomedicine. An enone-containing triglyceride derivative was obtained, by an environmentally friendly chemical procedure from high oleic sunflower oil that could be cross-linked with diamines. In a similar way, triglycerides containing secondary allylic alcohols can be obtained that can be further functionalized with acrylate or phosphorus-containing derivatives to obtain flame-retardant thermosets.

  • poly ether urethane networks from renewable resources as candidate biomaterials synthesis and characterization
    Biomacromolecules, 2007
    Co-Authors: Gerard Lligadas, Joan Carles Ronda, Marina Galià, Virginia Cádiz
    Abstract:

    A series of poly(ether urethane) networks were synthesized from Epoxidized Methyl-Oleate-based polyether polyol and 1,3-propandiol using l-lysine diisocyanate as a nontoxic coupling agent. Polyurethanes with different hard segment contents were prepared to tune the final properties of the materials. The polyurethanes were fully chemically and physically characterized, including water uptake and in vitro hydrolytic degradation measurements. The weight loss of the polyurethanes was traced, and the changes in the surface morphology with the degradation time were examined by scanning electron microscopy. The experimental results revealed that the hard segment content is the main factor that controls the physical, mechanical, and degradation properties of these polymers. The observed diversity in material properties suggests that these polyurethanes may be useful for a wide range of biomedical polymer applications.

  • synthesis and characterization of polyurethanes from Epoxidized Methyl Oleate based polyether polyols as renewable resources
    Journal of Polymer Science Part A, 2006
    Co-Authors: Gerard Lligadas, Massimo Galia, Joan Carles Ronda, Ursula Biermann, Jürgen O. Metzger
    Abstract:

    Oligomeric polyether polyols were obtained through the acid-catalyzed ring-opening polymerization of Epoxidized Methyl Oleate and the subsequent partial reduction of ester groups to give primary alcohols. The oligomers were characterized with titration, spectroscopic techniques (Fourier transform infrared and nuclear magnetic resonance), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, size exclusion chromatography, and differential scanning calorimetry. Depending on the degree of reduction, polyols of different hydroxyl content values were obtained and were reacted with 4,4′-Methylenebis(phenyl isocyanate) to yield polyurethanes. These materials, which were characterized by differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical thermal analysis, could behave as hard rubbers or rigid plastics. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 634–645, 2006

Virginia Cádiz - One of the best experts on this subject based on the ideXlab platform.

  • biobased polyurethanes from polyether polyols obtained by ionic coordinative polymerization of Epoxidized Methyl Oleate
    Journal of Polymer Science Part A, 2010
    Co-Authors: E. Del Rio, Massimo Galia, Gerard Lligadas, Joan Carles Ronda, Virginia Cádiz
    Abstract:

    A series of poly(ether urethane) networks were synthesized from polyether polyols obtained by ionic-coordinative polymerization of Epoxidized Methyl Oleate (EMO) using 4,4′-Methylenebis(phenyl isocyanate) or l-lysine diisocyanate as coupling agents. Moreover, a variety of segmented poly(ether urethane) networks with different hard segment contents were obtained using 1,3-propanediol as the chain extender. The materials were characterized by differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical thermal analysis, and tensile properties. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010

  • vegetable oil based thermosetting polymers
    European Journal of Lipid Science and Technology, 2010
    Co-Authors: Marina Galià, Gerard Lligadas, Joan Carles Ronda, Lucas Montero De Espinosa, Virginia Cádiz
    Abstract:

    Vegetable oils are excellent renewable raw materials for thermosetting polymers. By the direct polymerization of triglyceride C=C, we obtained organic-inorganic hybrid materials with promising properties for optical applications by the hydrosilylation of alkenyl-terminated fatty acid derivatives. The presence of double bonds in triglycerides makes it possible to attach some functional groups through chemical modification, and we describe various chemical pathways for functionalizing triglycerides and fatty acids. Epoxidation is one of the most interesting chemical modifications that leads to Epoxidized vegetable oils. We report the preparation of biobased polyhedral oligomeric silsesquioxanes-nanocomposites from Epoxidized linseed oil. Moreover, we describe the preparation of a new family of Epoxidized Methyl Oleate-based polyether polyols, which were used in the synthesis of polyurethanes with specific applications: silicon-containing polyurethanes with enhanced flame-retardant properties and polyurethane networks with potential applications in biomedicine. An enone-containing triglyceride derivative was obtained, by an environmentally friendly chemical procedure from high oleic sunflower oil that could be cross-linked with diamines. In a similar way, triglycerides containing secondary allylic alcohols can be obtained that can be further functionalized with acrylate or phosphorus-containing derivatives to obtain flame-retardant thermosets.

  • poly ether urethane networks from renewable resources as candidate biomaterials synthesis and characterization
    Biomacromolecules, 2007
    Co-Authors: Gerard Lligadas, Joan Carles Ronda, Marina Galià, Virginia Cádiz
    Abstract:

    A series of poly(ether urethane) networks were synthesized from Epoxidized Methyl-Oleate-based polyether polyol and 1,3-propandiol using l-lysine diisocyanate as a nontoxic coupling agent. Polyurethanes with different hard segment contents were prepared to tune the final properties of the materials. The polyurethanes were fully chemically and physically characterized, including water uptake and in vitro hydrolytic degradation measurements. The weight loss of the polyurethanes was traced, and the changes in the surface morphology with the degradation time were examined by scanning electron microscopy. The experimental results revealed that the hard segment content is the main factor that controls the physical, mechanical, and degradation properties of these polymers. The observed diversity in material properties suggests that these polyurethanes may be useful for a wide range of biomedical polymer applications.