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William D. Coggio - One of the best experts on this subject based on the ideXlab platform.
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development of structure property relationships that allow independent control of glass transition temperature melting temperature and rheology in a library of bio based succinate Polyester Polyols
Polymer, 2017Co-Authors: Alan K. Schrock, Heather S. C. Hamilton, Cathlene Del Rosario, Kenneth Ulrich, Baylen D. Thompson, Carl Jacky Saintlouis, William D. CoggioAbstract:Abstract A library of 20 bio-based succinate (SA) diol, co-diol, and co-diacid Polyester Polyols (PESPs) was generated and characterized, giving detailed understanding for tuning of their thermal transitions and rheological parameters. SA and 1,3-propanediol, 1,4-butanediol (BDO), 1,6-hexanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, diethylene glycol (DEG), adipic acid, or sebacic acid, and the blended diols were oligomerized to 1000 and 2000 Da Mn. The SA PESP melting point and its ability to crystallize can be set by controlling the structures and ratios of co-diols or co-diacids. We also show that the PESPs follow the expected Arrhenius temperature–viscosity relationship, but with a clear break in activation energy between PESPs with and without pendent methyl substituents and with DEG. PESP glass transition temperature, melting points, and rheology can be controlled independently by use of co-monomers with and without pendent methyl groups and with DEG.
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Development of structure–property relationships that allow independent control of glass transition temperature, melting temperature, and rheology in a library of bio-based succinate Polyester Polyols
Polymer, 2017Co-Authors: Alan K. Schrock, Heather S. C. Hamilton, Cathlene Del Rosario, Kenneth Ulrich, Baylen D. Thompson, Carl Jacky Saint-louis, William D. CoggioAbstract:Abstract A library of 20 bio-based succinate (SA) diol, co-diol, and co-diacid Polyester Polyols (PESPs) was generated and characterized, giving detailed understanding for tuning of their thermal transitions and rheological parameters. SA and 1,3-propanediol, 1,4-butanediol (BDO), 1,6-hexanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, diethylene glycol (DEG), adipic acid, or sebacic acid, and the blended diols were oligomerized to 1000 and 2000 Da Mn. The SA PESP melting point and its ability to crystallize can be set by controlling the structures and ratios of co-diols or co-diacids. We also show that the PESPs follow the expected Arrhenius temperature–viscosity relationship, but with a clear break in activation energy between PESPs with and without pendent methyl substituents and with DEG. PESP glass transition temperature, melting points, and rheology can be controlled independently by use of co-monomers with and without pendent methyl groups and with DEG.
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Thermal characterization and crystallization kinetics of Polyester Polyols derived from adipic acid and bio-based succinic acid with 1,4-butanediol and 1,6-hexanediol
Polymer, 2016Co-Authors: Alan K. Schrock, Heather S. C. Hamilton, Natalie D. Johnson, Cathlene Del Rosario, B.d. Thompson, Kenneth Ulrich, William D. CoggioAbstract:Abstract Crystallization kinetics, thermodynamics, and powder XRD measurements were performed on Polyester Polyols (PESP) made from succinic acid, SA, or adipic acid, AA, with 1,4-butanediol, BDO, or 1,6-hexanediol, HDO, at 2000 Da Mn. The SA BDO PESP exhibited the greatest crystallization supercooling. The Avrami crystallization kinetics n values are 4 or higher, indicative of sporadic nucleation of spherulitic crystals. At similar crystallization t1/2, SA BDO Keq determined from ΔGc is ten times greater and SA HDO is five times greater than AA BDO Keq. AA BDO and AA HDO have equivalent Keq at similar t1/2. Increasing the diol chain length from four carbons to six carbons increases the ΔGc temperature dependence for SA PESP, but has little impact on the ΔGc temperature dependence of AA PESP. Powder XRD shows that these PESPs contain 35%–40% macrocrystals comprised of nanocrystals with average dimensions of 6–10 nm per side.
Zilin Dai - One of the best experts on this subject based on the ideXlab platform.
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Transparent Polyester polyol-based polyurethane coatings: The effect of alcohols
2013Co-Authors: Junrui Zhang, Weiping Tu, Zilin DaiAbstract:A series of Polyester Polyols were synthesized using 1,6-hexanediol (HDO), 1,4-cyclohexanedimethanol (1,4-CHDM) and trimethylol propane (TMP), alone or in combination with 1,4-cyclohexanedicarboxylic acid and adipic acid. The Polyester Polyols were reacted with isocyanate trimers to form polyurethane (PU) coatings. Physical properties of the Polyesters such as hydroxyl value, acid value, molecular weight, viscosity, and glass transition temperature (T (g)) had been determined, and the IR spectroscopic analyses of Polyesters/PU were reported. The properties (impact resistance, film flexibility, hardness, optical transmittance, chemical resistance, water absorption, thermostability, and phase separation) of the PU coatings so prepared were characterized. The viscosities of Polyester Polyols were dependent on the structure of the alcohols. Polyester polyol containing only linear aliphatic diol (HDO) was a transparent liquid at room temperature. The viscosity was increased by raising the molar ratio of 1,4-CHDM and/or TMP. All PU coatings had excellent flexibility, impact resistance, and hardness. The coatings derived from diol CHDM had the highest hardness, and the PU derived from diol HDO had the lowest hardness. The chemical resistance and water absorption improved with greater molar ratios of 1,4-CHDM or TMP. Results of differential scanning calorimetry and wide-angle X-ray diffraction indicated that there was no obvious crystallinity in the PU networks. Dynamic mechanical analysis (DMA) results revealed that both CHDM and TMP can increase the T (g) of PU, and the crosslinking density improved with increased molar ratio of TMP. Atomic force microscope (AFM) and DMA analysis revealed that the PU coatings had no obvious microphase separation, which enabled them to have excellent properties, and the different composition in Polyols did not have significant influence on transmittance in the visible region. Results of thermogravimetric measurements indicated that all the PU coatings had good thermal stability.
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synthesis and characterization of transparent and high impact resistance polyurethane coatings based on Polyester Polyols and isocyanate trimers
Progress in Organic Coatings, 2012Co-Authors: Junrui Zhang, Zilin DaiAbstract:Abstract A series of Polyester Polyols were synthesized by polycondensation reaction using adipic acid (AA), 1,4-cyclohexanedicarboxylic acid (1,4-CHDA), and 1,6-hexanediol (HDO), 1,4-cyclohexanedimethanol (1,4-CHDM) and trimethylol propane (TMP), in which the molar ratio of the reactants AA/1,4-CHDA was varied. These series of Polyols were reacted with isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI), alone or in combination, to form polyurethane (PU) coatings. The physicochemical properties (chemical structure, hydroxyl value, acid value, and molecular weight) of the Polyols so synthesized and the mechanical and optical properties (impact resistance, film flexibility, optical transmittance and phase separation) of the PU coatings so prepared were characterized with FTIR spectroscopy, wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and atomic force microscopy (AFM). The results of this study show that the AA/1,4-CHDA molar ratio, the isocyanate used, and the NCO/OH ratio all have a significant impact on the properties of the PU coatings. While AA/1,4-CHDA molar ratio does not seem to affect the film flexibility and optical transmittance of the PU coatings, it has a significant effect on the impact resistance of the coatings. Impact resistance of the PU coatings increases as the AA/1,4-CHDA molar ratio decreases (i.e. more 1,4-CHDA used). PU coatings based on IPDI and combination of IPDI and HDI exhibit higher impact resistance and optical transmittance than HDI-based coatings. While changing NCO/OH ratio has only a slight impact on the optical transmittance and little effect on film flexibility, impact resistance of the PU coatings first increase, then decline with an increase in NCO/OH ratio.
Alan K. Schrock - One of the best experts on this subject based on the ideXlab platform.
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development of structure property relationships that allow independent control of glass transition temperature melting temperature and rheology in a library of bio based succinate Polyester Polyols
Polymer, 2017Co-Authors: Alan K. Schrock, Heather S. C. Hamilton, Cathlene Del Rosario, Kenneth Ulrich, Baylen D. Thompson, Carl Jacky Saintlouis, William D. CoggioAbstract:Abstract A library of 20 bio-based succinate (SA) diol, co-diol, and co-diacid Polyester Polyols (PESPs) was generated and characterized, giving detailed understanding for tuning of their thermal transitions and rheological parameters. SA and 1,3-propanediol, 1,4-butanediol (BDO), 1,6-hexanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, diethylene glycol (DEG), adipic acid, or sebacic acid, and the blended diols were oligomerized to 1000 and 2000 Da Mn. The SA PESP melting point and its ability to crystallize can be set by controlling the structures and ratios of co-diols or co-diacids. We also show that the PESPs follow the expected Arrhenius temperature–viscosity relationship, but with a clear break in activation energy between PESPs with and without pendent methyl substituents and with DEG. PESP glass transition temperature, melting points, and rheology can be controlled independently by use of co-monomers with and without pendent methyl groups and with DEG.
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Development of structure–property relationships that allow independent control of glass transition temperature, melting temperature, and rheology in a library of bio-based succinate Polyester Polyols
Polymer, 2017Co-Authors: Alan K. Schrock, Heather S. C. Hamilton, Cathlene Del Rosario, Kenneth Ulrich, Baylen D. Thompson, Carl Jacky Saint-louis, William D. CoggioAbstract:Abstract A library of 20 bio-based succinate (SA) diol, co-diol, and co-diacid Polyester Polyols (PESPs) was generated and characterized, giving detailed understanding for tuning of their thermal transitions and rheological parameters. SA and 1,3-propanediol, 1,4-butanediol (BDO), 1,6-hexanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, diethylene glycol (DEG), adipic acid, or sebacic acid, and the blended diols were oligomerized to 1000 and 2000 Da Mn. The SA PESP melting point and its ability to crystallize can be set by controlling the structures and ratios of co-diols or co-diacids. We also show that the PESPs follow the expected Arrhenius temperature–viscosity relationship, but with a clear break in activation energy between PESPs with and without pendent methyl substituents and with DEG. PESP glass transition temperature, melting points, and rheology can be controlled independently by use of co-monomers with and without pendent methyl groups and with DEG.
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Thermal characterization and crystallization kinetics of Polyester Polyols derived from adipic acid and bio-based succinic acid with 1,4-butanediol and 1,6-hexanediol
Polymer, 2016Co-Authors: Alan K. Schrock, Heather S. C. Hamilton, Natalie D. Johnson, Cathlene Del Rosario, B.d. Thompson, Kenneth Ulrich, William D. CoggioAbstract:Abstract Crystallization kinetics, thermodynamics, and powder XRD measurements were performed on Polyester Polyols (PESP) made from succinic acid, SA, or adipic acid, AA, with 1,4-butanediol, BDO, or 1,6-hexanediol, HDO, at 2000 Da Mn. The SA BDO PESP exhibited the greatest crystallization supercooling. The Avrami crystallization kinetics n values are 4 or higher, indicative of sporadic nucleation of spherulitic crystals. At similar crystallization t1/2, SA BDO Keq determined from ΔGc is ten times greater and SA HDO is five times greater than AA BDO Keq. AA BDO and AA HDO have equivalent Keq at similar t1/2. Increasing the diol chain length from four carbons to six carbons increases the ΔGc temperature dependence for SA PESP, but has little impact on the ΔGc temperature dependence of AA PESP. Powder XRD shows that these PESPs contain 35%–40% macrocrystals comprised of nanocrystals with average dimensions of 6–10 nm per side.
Françoise Mechin - One of the best experts on this subject based on the ideXlab platform.
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New bio-based thermoplastic polyurethane elastomers from isosorbide and rapeseed oil derivatives
Industrial Crops and Products, 2018Co-Authors: Héloïse Blache, Etienne Fleury, Françoise Mechin, Alain Rousseau, Jean-pierre Pascault, Pierre Alcouffe, Nicolas Jacquel, René Saint-loupAbstract:Thermoplastic polyurethanes (TPUs) from fatty acids dimer-based Polyester Polyols, 4,4′-methylene bis(phenyl isocyanate) (MDI) and isosorbide (ISO) as chain extender were successfully synthesized by a two-stage synthesis. TPUs obtained from isosorbide were compared to the model 1,4-butanediol (BDO) −based materials. Differential scanning calorimetry revealed the phase-separated structure of these materials that displayed a typical thermoplastic elastomer behavior by dynamic mechanical analysis. Samples were further analyzed by transmission electronic microscopy, atomic force microscopy and compression set; hardness and water uptake were also monitored. Isosorbide was found to slightly increase the glass transition and melting temperatures of MDI-based hard segments, and to slightly decrease the stability and quality of phase segregation. This resulted in an increase in rubber modulus and hardness, shape retention, in a slight increase in the temperature of the α relaxation of the soft segment domains and in a characteristic microphase morphology. Moreover the use of the rather hydrophobic fatty acid-based soft segment allowed to keep the water uptake at a rather low level, in spite of the presence of isosorbide in the formulation.
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High elongation thermoplastic Polyester-urethanes based on widely available diacid intermediates
Journal of Applied Polymer Science, 2016Co-Authors: Marion Tharcis, Thierry Badel, Stéphane Jéol, Etienne Fleury, Françoise MechinAbstract:A series of new ,-dihydroxy terminated Polyester oligomers are synthesized from the condensation reaction of various aliphatic diols with a mixture of diacids rich in 2-methylglutaric acid, MGA, an abundant and well-defined industrial product. Their adipic acid (AA)-based counterparts are also prepared and the physico-chemical properties of both types of Polyols are thoroughly characterized. All these Polyester Polyols are then used to prepare segmented polyurethanes following a two-stage process, by reacting them successively with 4,4-diphenylmethane diisocyanate, and 1,4-butanediol. The resulting materials are then evaluated with respect to their thermal and dynamic or static mechanical properties. The observed characteristics and behaviors are quite similar between AA- or MGA-based polyurethanes, except for the tendency of AA-based samples to display partially crystallized soft domains. Such a phenomenon is prevented in MGA-based samples because of the methyl side group, resulting in remarkably higher ultimate elongations for the new thermoplastic polyurethanes derived from MGA.
Junrui Zhang - One of the best experts on this subject based on the ideXlab platform.
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Transparent Polyester polyol-based polyurethane coatings: The effect of alcohols
2013Co-Authors: Junrui Zhang, Weiping Tu, Zilin DaiAbstract:A series of Polyester Polyols were synthesized using 1,6-hexanediol (HDO), 1,4-cyclohexanedimethanol (1,4-CHDM) and trimethylol propane (TMP), alone or in combination with 1,4-cyclohexanedicarboxylic acid and adipic acid. The Polyester Polyols were reacted with isocyanate trimers to form polyurethane (PU) coatings. Physical properties of the Polyesters such as hydroxyl value, acid value, molecular weight, viscosity, and glass transition temperature (T (g)) had been determined, and the IR spectroscopic analyses of Polyesters/PU were reported. The properties (impact resistance, film flexibility, hardness, optical transmittance, chemical resistance, water absorption, thermostability, and phase separation) of the PU coatings so prepared were characterized. The viscosities of Polyester Polyols were dependent on the structure of the alcohols. Polyester polyol containing only linear aliphatic diol (HDO) was a transparent liquid at room temperature. The viscosity was increased by raising the molar ratio of 1,4-CHDM and/or TMP. All PU coatings had excellent flexibility, impact resistance, and hardness. The coatings derived from diol CHDM had the highest hardness, and the PU derived from diol HDO had the lowest hardness. The chemical resistance and water absorption improved with greater molar ratios of 1,4-CHDM or TMP. Results of differential scanning calorimetry and wide-angle X-ray diffraction indicated that there was no obvious crystallinity in the PU networks. Dynamic mechanical analysis (DMA) results revealed that both CHDM and TMP can increase the T (g) of PU, and the crosslinking density improved with increased molar ratio of TMP. Atomic force microscope (AFM) and DMA analysis revealed that the PU coatings had no obvious microphase separation, which enabled them to have excellent properties, and the different composition in Polyols did not have significant influence on transmittance in the visible region. Results of thermogravimetric measurements indicated that all the PU coatings had good thermal stability.
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synthesis and characterization of transparent and high impact resistance polyurethane coatings based on Polyester Polyols and isocyanate trimers
Progress in Organic Coatings, 2012Co-Authors: Junrui Zhang, Zilin DaiAbstract:Abstract A series of Polyester Polyols were synthesized by polycondensation reaction using adipic acid (AA), 1,4-cyclohexanedicarboxylic acid (1,4-CHDA), and 1,6-hexanediol (HDO), 1,4-cyclohexanedimethanol (1,4-CHDM) and trimethylol propane (TMP), in which the molar ratio of the reactants AA/1,4-CHDA was varied. These series of Polyols were reacted with isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI), alone or in combination, to form polyurethane (PU) coatings. The physicochemical properties (chemical structure, hydroxyl value, acid value, and molecular weight) of the Polyols so synthesized and the mechanical and optical properties (impact resistance, film flexibility, optical transmittance and phase separation) of the PU coatings so prepared were characterized with FTIR spectroscopy, wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and atomic force microscopy (AFM). The results of this study show that the AA/1,4-CHDA molar ratio, the isocyanate used, and the NCO/OH ratio all have a significant impact on the properties of the PU coatings. While AA/1,4-CHDA molar ratio does not seem to affect the film flexibility and optical transmittance of the PU coatings, it has a significant effect on the impact resistance of the coatings. Impact resistance of the PU coatings increases as the AA/1,4-CHDA molar ratio decreases (i.e. more 1,4-CHDA used). PU coatings based on IPDI and combination of IPDI and HDI exhibit higher impact resistance and optical transmittance than HDI-based coatings. While changing NCO/OH ratio has only a slight impact on the optical transmittance and little effect on film flexibility, impact resistance of the PU coatings first increase, then decline with an increase in NCO/OH ratio.