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In Woo Cheong - One of the best experts on this subject based on the ideXlab platform.
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synthesis of core shell polyurethane urea nanoparticles containing 4 4 methylenedi p phenyl Diisocyanate and Isophorone Diisocyanate by self assembled neutralization emulsification
Chemical Communications, 2004Co-Authors: In Woo Cheong, Junghyun KimAbstract:Polyurethane–urea nanoparticles containing 4,4′-methylenedi-p-phenyl Diisocyanate and Isophorone Diisocyanate were synthesized by utilizing self-assembled neutralization emulsification and their particle morphology could be controlled.
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Synthesis of core–shell polyurethane–urea nanoparticles containing 4,4′-methylenedi-p-phenyl Diisocyanate and Isophorone Diisocyanate by self-assembled neutralization emulsification
Chemical Communications, 2004Co-Authors: In Woo CheongAbstract:Polyurethane–urea nanoparticles containing 4,4′-methylenedi-p-phenyl Diisocyanate and Isophorone Diisocyanate were synthesized by utilizing self-assembled neutralization emulsification and their particle morphology could be controlled.
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synthesis and characterization of polyurethane urea nanoparticles containing methylenedi p phenyl Diisocyanate and Isophorone Diisocyanate
Journal of Polymer Science Part A, 2004Co-Authors: In Woo Cheong, Hyun Chul Kong, Jeong Ho AnAbstract:Water-based polyurethane–urea (WPUU) nanoparticles containing 4,4′-methylenedi-p-phenyl Diisocyanate (MDI) and Isophorone Diisocyanate (IPDI) were synthesized by a stepwise prepolymer mixing process, that is, the consecutive formation of hydroxyl-terminated and isocyanate-terminated polyurethane prepolymers. The reaction behavior, chemical structure, and consequent morphology of the polyurethane prepolymers and WPUU were investigated with Fourier transform infrared (FTIR), gel permeation chromatography, and NMR techniques with MDI concentrations ranging from 0 (pure IPDI) to 50% with respect to the total moles of isocyanate. Wide-angle X-ray diffraction and differential scanning calorimetry patterns showed that the crystallinity of WPUU, which mostly originated from crystallizable poly(tetramethylene adipate) polyol, was significantly affected by the MDI content. Both the crystallinity and melting temperature of WPUU decreased as the MDI content increased. Deconvoluted relative peak areas of the carbonyl region in the FTIR spectrum revealed that the effect of hydrogen bonding among the hard segments became favorable as the MDI content increased, whereas the hydrogen bonding of the soft segments significantly decreased. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4353–4369, 2004
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Synthesis and characterization of polyurethane–urea nanoparticles containing methylenedi-p-phenyl Diisocyanate and Isophorone Diisocyanate
Journal of Polymer Science Part A: Polymer Chemistry, 2004Co-Authors: In Woo Cheong, Hyun Chul Kong, Junghyun KimAbstract:Water-based polyurethane–urea (WPUU) nanoparticles containing 4,4′-methylenedi-p-phenyl Diisocyanate (MDI) and Isophorone Diisocyanate (IPDI) were synthesized by a stepwise prepolymer mixing process, that is, the consecutive formation of hydroxyl-terminated and isocyanate-terminated polyurethane prepolymers. The reaction behavior, chemical structure, and consequent morphology of the polyurethane prepolymers and WPUU were investigated with Fourier transform infrared (FTIR), gel permeation chromatography, and NMR techniques with MDI concentrations ranging from 0 (pure IPDI) to 50% with respect to the total moles of isocyanate. Wide-angle X-ray diffraction and differential scanning calorimetry patterns showed that the crystallinity of WPUU, which mostly originated from crystallizable poly(tetramethylene adipate) polyol, was significantly affected by the MDI content. Both the crystallinity and melting temperature of WPUU decreased as the MDI content increased. Deconvoluted relative peak areas of the carbonyl region in the FTIR spectrum revealed that the effect of hydrogen bonding among the hard segments became favorable as the MDI content increased, whereas the hydrogen bonding of the soft segments significantly decreased. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4353–4369, 2004
Junghyun Kim - One of the best experts on this subject based on the ideXlab platform.
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synthesis of core shell polyurethane urea nanoparticles containing 4 4 methylenedi p phenyl Diisocyanate and Isophorone Diisocyanate by self assembled neutralization emulsification
Chemical Communications, 2004Co-Authors: In Woo Cheong, Junghyun KimAbstract:Polyurethane–urea nanoparticles containing 4,4′-methylenedi-p-phenyl Diisocyanate and Isophorone Diisocyanate were synthesized by utilizing self-assembled neutralization emulsification and their particle morphology could be controlled.
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Synthesis and characterization of polyurethane–urea nanoparticles containing methylenedi-p-phenyl Diisocyanate and Isophorone Diisocyanate
Journal of Polymer Science Part A: Polymer Chemistry, 2004Co-Authors: In Woo Cheong, Hyun Chul Kong, Junghyun KimAbstract:Water-based polyurethane–urea (WPUU) nanoparticles containing 4,4′-methylenedi-p-phenyl Diisocyanate (MDI) and Isophorone Diisocyanate (IPDI) were synthesized by a stepwise prepolymer mixing process, that is, the consecutive formation of hydroxyl-terminated and isocyanate-terminated polyurethane prepolymers. The reaction behavior, chemical structure, and consequent morphology of the polyurethane prepolymers and WPUU were investigated with Fourier transform infrared (FTIR), gel permeation chromatography, and NMR techniques with MDI concentrations ranging from 0 (pure IPDI) to 50% with respect to the total moles of isocyanate. Wide-angle X-ray diffraction and differential scanning calorimetry patterns showed that the crystallinity of WPUU, which mostly originated from crystallizable poly(tetramethylene adipate) polyol, was significantly affected by the MDI content. Both the crystallinity and melting temperature of WPUU decreased as the MDI content increased. Deconvoluted relative peak areas of the carbonyl region in the FTIR spectrum revealed that the effect of hydrogen bonding among the hard segments became favorable as the MDI content increased, whereas the hydrogen bonding of the soft segments significantly decreased. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4353–4369, 2004
Peter M Fredericks - One of the best experts on this subject based on the ideXlab platform.
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infrared microspectroscopic study of the thermo oxidative degradation of hydroxy terminated polybutadiene Isophorone Diisocyanate polyurethane rubber
Polymer Degradation and Stability, 2007Co-Authors: Dylan J Nagle, Mathew Celina, Llewellyn Rintoul, Peter M FredericksAbstract:Hydroxy-terminated polybutadiene/Isophorone Diisocyanate (HTPB/IPDI) polyurethane rubber which was aged in air at elevated temperatures has been studied by infrared microspectroscopy. Spectra were collected in transmission mode on microtomed samples. Analysis of sets of spectra taken across the sectioned material showed that most of the degradation occurred in the polybutadiene part of the polymer and that the urethane linkage was essentially unchanged. The trans isomer of the polybutadiene appears to be preferentially degraded compared with the vinyl isomer. The IR technique does not provide significant information about the cis isomer. The IR spectra indicated that likely degradation products included acids, esters, alcohols, and small amounts of other products containing a carbonyl functional group. Band area ratios, supported by a principal components analysis, were used to derive degradation profiles for the material. These profiles were steep-sided indicating an oxygen diffusion limited process.
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Infrared microspectroscopic study of the thermo-oxidative degradation of hydroxy-terminated polybutadiene/Isophorone Diisocyanate polyurethane rubber
Polymer Degradation and Stability, 2007Co-Authors: Dylan J Nagle, Mathew Celina, Llewellyn Rintoul, Peter M FredericksAbstract:Hydroxy-terminated polybutadiene/Isophorone Diisocyanate (HTPB/IPDI) polyurethane rubber which was aged in air at elevated temperatures has been studied by infrared microspectroscopy. Spectra were collected in transmission mode on microtomed samples. Analysis of sets of spectra taken across the sectioned material showed that most of the degradation occurred in the polybutadiene part of the polymer and that the urethane linkage was essentially unchanged. The trans isomer of the polybutadiene appears to be preferentially degraded compared with the vinyl isomer. The IR technique does not provide significant information about the cis isomer. The IR spectra indicated that likely degradation products included acids, esters, alcohols, and small amounts of other products containing a carbonyl functional group. Band area ratios, supported by a principal components analysis, were used to derive degradation profiles for the material. These profiles were steep-sided indicating an oxygen diffusion limited process.
Andrea Hartwig - One of the best experts on this subject based on the ideXlab platform.
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The MAK‐Collection for Occupational Health and Safety - Hexamethylene Diisocyanate, 2,4‐toluene Diisocyanate, 2,6‐toluene Diisocyanate, Isophorone Diisocyanate and 4,4′‐methylene diphenyl Diisocyanate – Determination of hexamethylenediamine, 2,4‐tolu
The MAK Collection for Occupational Health and Safety, 2017Co-Authors: John Cocker, Lygia Therese Budnik, Th. Göen, Gabriele Leng, Wolfgang Gries, Johannes Müller, Andrea HartwigAbstract:The working group “Analyses in Biological Materials” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area verified the present biomonitoring method. The described method allows the simultaneous determination of the metabolites of hexamethylene Diisocyanate (HDI), 2,4-toluene Diisocyanate and 2,6-toluene Diisocyanate (TDI), Isophorone Diisocyanate (IPDI) and methylene diphenyl Diisocyanate (MDI) in human urine. After acid hydrolysis the released amines, hexamethylenediamine (HDA), 2,4-toluenediamine, and 2,6-toluenediamine (TDA), Isophorone diamine (IPDA) and 4,4′-methylenedianiline (4,4′-MDA) are extracted from urine, derivatised using heptafluorobutyric anhydride and quantified by NCI-GC-MS. The method was extensively validated and the reliability data were confirmed by independent laboratories, which have established and cross-checked the whole procedure. Keywords: hexamethylene Diisocyanate; HDI; 2,4-toluene Diisocyanate; 2,4-TDI; 2,6-toluene Diisocyanate; 2,6-TDI; Isophorone Diisocyanate; IPDI; methylene diphenyl Diisocyanate; MDI; hexamethylenediamine; HDA; 2,4-toluenediamine; 2,4-TDA; 2,6-toluenediamine; 2,6-TDA; Isophorone diamine; IPDA; 4,4′-methylene dianiline; MDA; urine; biomonitoring; analyses in biological materials; gas chromatography
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hexamethylene Diisocyanate 2 4 toluene Diisocyanate 2 6 toluene Diisocyanate Isophorone Diisocyanate and 4 4 methylene diphenyl Diisocyanate determination of hexamethylenediamine 2 4 toluenediamine 2 6 toluenediamine Isophoronediamine and 4 4 methyle
The MAK Collection for Occupational Health and Safety, 2017Co-Authors: John Cocker, Lygia Therese Budnik, Th. Göen, Gabriele Leng, Wolfgang Gries, Johannes Müller, K Jones, Andrea HartwigAbstract:The working group “Analyses in Biological Materials” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area verified the present biomonitoring method. The described method allows the simultaneous determination of the metabolites of hexamethylene Diisocyanate (HDI), 2,4-toluene Diisocyanate and 2,6-toluene Diisocyanate (TDI), Isophorone Diisocyanate (IPDI) and methylene diphenyl Diisocyanate (MDI) in human urine. After acid hydrolysis the released amines, hexamethylenediamine (HDA), 2,4-toluenediamine, and 2,6-toluenediamine (TDA), Isophorone diamine (IPDA) and 4,4′-methylenedianiline (4,4′-MDA) are extracted from urine, derivatised using heptafluorobutyric anhydride and quantified by NCI-GC-MS. The method was extensively validated and the reliability data were confirmed by independent laboratories, which have established and cross-checked the whole procedure. Keywords: hexamethylene Diisocyanate; HDI; 2,4-toluene Diisocyanate; 2,4-TDI; 2,6-toluene Diisocyanate; 2,6-TDI; Isophorone Diisocyanate; IPDI; methylene diphenyl Diisocyanate; MDI; hexamethylenediamine; HDA; 2,4-toluenediamine; 2,4-TDA; 2,6-toluenediamine; 2,6-TDA; Isophorone diamine; IPDA; 4,4′-methylene dianiline; MDA; urine; biomonitoring; analyses in biological materials; gas chromatography
M J Fernandezberridi - One of the best experts on this subject based on the ideXlab platform.
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thermal and fire behavior of Isophorone Diisocyanate based polyurethane foams containing conventional flame retardants
Journal of Applied Polymer Science, 2018Co-Authors: I. Eceiza, M J Fernandezberridi, A. Barrio, Loli Martin, M A Veganzones, Lourdes IrustaAbstract:This work reports on the fire behavior of Isophorone Diisocyanate-based polyurethane foams containing different conventional flame retardants (FRs) such as melamine, ammonium polyphosphate, aluminum hydroxide, expandable graphite, and their combinations. The foams were obtained in a laboratory scale and characterized in terms of their morphology, density, thermal stability, and fire behavior. According to atomic force microscopy, the incorporation of FRs decreased the phase separated domain size. The cellular structure of the foams was examined qualitatively by scanning electron microscopy while the quantitative analysis of the surrounding skin was performed by optical microscopy and Image J. The FR containing foams showed more and smaller cells. The thermogravimetric analysis showed that the FRs had no influence in the initial degradation temperature of the foams. However, the obtained residue values were higher than the theoretical ones, indicating that there was some type of interaction between the FRs and the foams. The fire behavior of polyurethane foams was studied by the cone calorimeter and the data showed that the introduction of expandable graphite and combinations of ammonium polyphosphate/melamine to the reference foam gave rise to a significant reduction in the total heat release. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 135, 45944.
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polyurethanes based on Isophorone Diisocyanate trimer and polypropylene glycol crosslinked by thermal reversible diels alder reactions
Journal of Applied Polymer Science, 2017Co-Authors: Lourdes Irusta, M J Fernandezberridi, June AizpuruaAbstract:Crosslinked self-healing polyurethanes based on Diels–Alder (DA) reaction were synthesized from a trifunctionalized Isophorone Diisocyanate (IPDI) and polypropyleneglycol prepolymer with furfuryl alcohol and a commercial bismaleimide. The DA reaction was followed by FTIR spectroscopy at different temperatures. From the infrared results the kinetic rate constants as well as the DA reaction reversibility were established. The retro DA reaction (rDA) and its reversibility was monitored by DSC according to the enthalpy involved in the process. The obtained polymers exhibited thermosetting properties at room temperature, although they showed thermoplastic behavior at high temperatures. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44543.
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synthesis of Isophorone Diisocyanate ipdi based waterborne polyurethanes comparison between zirconium and tin catalysts in the polymerization process
Progress in Organic Coatings, 2009Co-Authors: Haritz Sardon, Lourdes Irusta, M J FernandezberridiAbstract:In this work, a comparative study of the catalytic activity of tin and zirconium compounds in the polymerization of Isophorone Diisocyanate (IPDI) based waterborne polyurethanes is presented. Zirconium acetyl acetonate is much less toxic than the commonly used dibutyltin diacetate but it is deactivated in the presence of acid groups. Nevertheless, acid groups are commonly used in the synthesis of waterborne polyurethanes and therefore these groups have to be neutralized in advance for carrying out the synthesis using the zirconium catalyst. Moreover, FTIR and 13C NMR results have shown that in the presence of triethyl amine and tin catalyst, the secondary isocyanate group is more reactive than the primary group, while using the zirconium catalyst, the two isocyanate groups show the same reactivity.
