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Changes in gas - transport properties with the phase structure of blends containing styrene − butadiene − styrene triblock copolymer and poly (2,6 - dimethyl - 1,4 - phenylene oxide) / K. W. Song in Industrial & engineering chemistry research, Vol. 49 N° 14 (Juillet 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 14 (Juillet 2010) . - pp. 6587–6592 Titre : Changes in gas - transport properties with the phase structure of blends containing styrene − butadiene − styrene triblock copolymer and poly (2,6 - dimethyl - 1,4 - phenylene oxide) Type de document : texte imprimé Auteurs : K. W. Song, Auteur ; K. R. Ka, Auteur ; C. K. Kim, Auteur Année de publication : 2010 Article en page(s) : pp. 6587–6592 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Gas  transport  properties Résumé : Blend films prepared from styrene−butadiene−styrene triblock copolymer (SBS) and poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) in various compositions were examined to explore their application as gas separation membranes. PPO formed a single-phase mixture with hard styrene segments in SBS regardless of the blend composition. Therefore, an increase in the hard-phase volume with PPO blending resulted in phase structure changes: As the PPO content in the blend increased, the hard phase that was dispersed in the matrix formed by butadiene soft segments was converted into a continuous lamellar structure and finally formed a matrix of the blend by phase inversion. A decrease in the gas permeability and an increase in the gas selectivity were observed with increasing PPO content. The continuous soft phase was changed to the discrete phase in blends containing between 40 and 50 wt % PPO. As a result, an abrupt decrease in the gas permeability was observed at around these blend compositions. Permeability coefficients showed a small decrease as the upstream gas pressure increased when the hard phase formed a matrix, whereas they were not changed regardless of the upstream gas pressure when the soft segments formed the continuous phase. Plasticization caused by a polar penetrant was not observed in the SBS/PPO blend membranes. Our results show that blend films exhibiting desired gas permselectivity can be fabricated by controlling the phase-separated structure of SBS/PPO blends. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100565q [article] Changes in gas - transport properties with the phase structure of blends containing styrene − butadiene − styrene triblock copolymer and poly (2,6 - dimethyl - 1,4 - phenylene oxide) [texte imprimé] / K. W. Song, Auteur ; K. R. Ka, Auteur ; C. K. Kim, Auteur . - 2010 . - pp. 6587–6592. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 14 (Juillet 2010) . - pp. 6587–6592 Mots-clés : Gas  transport  properties Résumé : Blend films prepared from styrene−butadiene−styrene triblock copolymer (SBS) and poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) in various compositions were examined to explore their application as gas separation membranes. PPO formed a single-phase mixture with hard styrene segments in SBS regardless of the blend composition. Therefore, an increase in the hard-phase volume with PPO blending resulted in phase structure changes: As the PPO content in the blend increased, the hard phase that was dispersed in the matrix formed by butadiene soft segments was converted into a continuous lamellar structure and finally formed a matrix of the blend by phase inversion. A decrease in the gas permeability and an increase in the gas selectivity were observed with increasing PPO content. The continuous soft phase was changed to the discrete phase in blends containing between 40 and 50 wt % PPO. As a result, an abrupt decrease in the gas permeability was observed at around these blend compositions. Permeability coefficients showed a small decrease as the upstream gas pressure increased when the hard phase formed a matrix, whereas they were not changed regardless of the upstream gas pressure when the soft segments formed the continuous phase. Plasticization caused by a polar penetrant was not observed in the SBS/PPO blend membranes. Our results show that blend films exhibiting desired gas permselectivity can be fabricated by controlling the phase-separated structure of SBS/PPO blends. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100565q

Characteristics of polyurethane elastomer blends with poly (acrylonitrile - co - butadiene) rubber as an encapsulant for underwater sonar devices / H. G. Im in Industrial & engineering chemistry research, Vol. 49 N° 16 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7336–7342 Titre : Characteristics of polyurethane elastomer blends with poly (acrylonitrile - co - butadiene) rubber as an encapsulant for underwater sonar devices Type de document : texte imprimé Auteurs : H. G. Im, Auteur ; K. R. Ka, Auteur ; C. K. Kim, Auteur Année de publication : 2010 Article en page(s) : pp. 7336–7342 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Thermoplastic  Elastomer Résumé : Thermoplastic polyurethane elastomer (TPU) is widely used as an encapsulant in undersea sonar devices. Since sonar encapsulants are filled with a paraffin oil to prevent the ingress of seawater into the transducer, encapsulant materials possessing a lower swelling ratio for seawater and paraffin oil, along with better mechanical strength than TPU after impregnation, are desirable. To fabricate polymeric materials for application in sonar encapsulants, TPUs prepared with poly(tetramethylene glycol) (PTMG) and methyldiphenyldiisocyanate (MDI) were blended with poly(acrylonitrile-co-butadiene) rubber (NBR) containing various amounts of acrylonitrile (AN). The swelling ratios of the TPU/NBR blends in seawater were all lower than that of TPU, regardless of the AN content of the NBR, and the swelling ratio gradually decreased with increasing AN content of the NBR. The TPU blend with NBR containing 43 wt % AN exhibited a lower swelling ratio than TPU in paraffin oil. In addition, the TPU/NBR43 blend exhibited enhanced mechanical strength, as compared to TPU after being impregnated with seawater and paraffin oil. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100975n [article] Characteristics of polyurethane elastomer blends with poly (acrylonitrile - co - butadiene) rubber as an encapsulant for underwater sonar devices [texte imprimé] / H. G. Im, Auteur ; K. R. Ka, Auteur ; C. K. Kim, Auteur . - 2010 . - pp. 7336–7342. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7336–7342 Mots-clés : Thermoplastic  Elastomer Résumé : Thermoplastic polyurethane elastomer (TPU) is widely used as an encapsulant in undersea sonar devices. Since sonar encapsulants are filled with a paraffin oil to prevent the ingress of seawater into the transducer, encapsulant materials possessing a lower swelling ratio for seawater and paraffin oil, along with better mechanical strength than TPU after impregnation, are desirable. To fabricate polymeric materials for application in sonar encapsulants, TPUs prepared with poly(tetramethylene glycol) (PTMG) and methyldiphenyldiisocyanate (MDI) were blended with poly(acrylonitrile-co-butadiene) rubber (NBR) containing various amounts of acrylonitrile (AN). The swelling ratios of the TPU/NBR blends in seawater were all lower than that of TPU, regardless of the AN content of the NBR, and the swelling ratio gradually decreased with increasing AN content of the NBR. The TPU blend with NBR containing 43 wt % AN exhibited a lower swelling ratio than TPU in paraffin oil. In addition, the TPU/NBR43 blend exhibited enhanced mechanical strength, as compared to TPU after being impregnated with seawater and paraffin oil. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100975n

Effects of nonsolvent molecular structure and its content on the formation of the macroporous polyarylate layer coated onto the polyethylene separator / Sang Chul Roh in Industrial & engineering chemistry research, Vol. 50 N° 22 (Novembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 22 (Novembre 2011) . - pp. 12596–12605 Titre : Effects of nonsolvent molecular structure and its content on the formation of the macroporous polyarylate layer coated onto the polyethylene separator Type de document : texte imprimé Auteurs : Sang Chul Roh, Auteur ; Kwon Won Song, Auteur ; C. K. Kim, Auteur Année de publication : 2012 Article en page(s) : pp. 12596–12605 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Macroporous  Polyethylene Résumé : A macroporous polyarylate (PAR) layer was formed on a polyethylene (PE) separator from coating solutions containing PAR, tetrahydrofuran (THF) as the solvent, and various alcohols (or diols) as nonsolvents via a nonsolvent-induced phase separation (NIPS) process. The effects of the nonsolvent molecular structure and its content on the morphology of the coating layer were explored. Droplets grew by a coarsening process after the onset of phase separation by solvent evaporation, and then leveled off at a fixed droplet size. The final pore size increased with the molecular weight of the alcohol (or diol) when the composition of the coating solution was fixed. It increased as the nonsolvent content in the coating solution increased, while it decreased as the PAR content in the coating solution increased. The meltdown temperature of the separator increased with the macroporous PAR coating, while air permeability of the separator was reduced with the coating. Changes in the meltdown temperature and air permeability depended on the morphology of the coating layer. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201716m [article] Effects of nonsolvent molecular structure and its content on the formation of the macroporous polyarylate layer coated onto the polyethylene separator [texte imprimé] / Sang Chul Roh, Auteur ; Kwon Won Song, Auteur ; C. K. Kim, Auteur . - 2012 . - pp. 12596–12605. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 22 (Novembre 2011) . - pp. 12596–12605 Mots-clés : Macroporous  Polyethylene Résumé : A macroporous polyarylate (PAR) layer was formed on a polyethylene (PE) separator from coating solutions containing PAR, tetrahydrofuran (THF) as the solvent, and various alcohols (or diols) as nonsolvents via a nonsolvent-induced phase separation (NIPS) process. The effects of the nonsolvent molecular structure and its content on the morphology of the coating layer were explored. Droplets grew by a coarsening process after the onset of phase separation by solvent evaporation, and then leveled off at a fixed droplet size. The final pore size increased with the molecular weight of the alcohol (or diol) when the composition of the coating solution was fixed. It increased as the nonsolvent content in the coating solution increased, while it decreased as the PAR content in the coating solution increased. The meltdown temperature of the separator increased with the macroporous PAR coating, while air permeability of the separator was reduced with the coating. Changes in the meltdown temperature and air permeability depended on the morphology of the coating layer. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201716m

Enhancement of meltdown temperature of the polyethylene lithium-ion battery separator via surface coating with polymers having high thermal resistance / Y. S. Chung in Industrial & engineering chemistry research, Vol. 48 N° 9 (Mai 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 9 (Mai 2009) . - pp. 4346–4351 Titre : Enhancement of meltdown temperature of the polyethylene lithium-ion battery separator via surface coating with polymers having high thermal resistance Type de document : texte imprimé Auteurs : Y. S. Chung, Auteur ; S. H. Yoo, Auteur ; C. K. Kim, Auteur Année de publication : 2009 Article en page(s) : pp. 4346–4351 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Lithium-ion  battery  Polyethylene  separators  Thermal  runaway  reactions Résumé : When a lithium-ion battery is overcharged, it starts to self-heat because of exothermic reactions occurring within the components of the cell. Separator shutdown is a useful safety feature for preventing thermal runaway reactions in lithium-ion batteries. The polyethylene (PE) separators used here had shutdown temperatures of around 135 °C. Because the cell temperature continues to increase before actually beginning to cool even after shutdown, the separator should have a higher meltdown temperature than the shutdown temperature to work as an insulator even above the shutdown temperature. To enhance the meltdown temperature of the separator, in this study, a PE separator was coated with polymers synthesized from various ethylene glycol dimethacrylate monomers. When the separator was coated with polymer synthesized from diethylene glycol dimethacrylate (DEGDMA), its shutdown temperature and meltdown temperature were increased to 142 and 155 °C, respectively. Furthermore, a slight increase in the air permeability of the separator was observed when the separator was coated with polymer synthesized from an ethanol solution containing the proper amount of DEGDMA. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900096z [article] Enhancement of meltdown temperature of the polyethylene lithium-ion battery separator via surface coating with polymers having high thermal resistance [texte imprimé] / Y. S. Chung, Auteur ; S. H. Yoo, Auteur ; C. K. Kim, Auteur . - 2009 . - pp. 4346–4351. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 9 (Mai 2009) . - pp. 4346–4351 Mots-clés : Lithium-ion  battery  Polyethylene  separators  Thermal  runaway  reactions Résumé : When a lithium-ion battery is overcharged, it starts to self-heat because of exothermic reactions occurring within the components of the cell. Separator shutdown is a useful safety feature for preventing thermal runaway reactions in lithium-ion batteries. The polyethylene (PE) separators used here had shutdown temperatures of around 135 °C. Because the cell temperature continues to increase before actually beginning to cool even after shutdown, the separator should have a higher meltdown temperature than the shutdown temperature to work as an insulator even above the shutdown temperature. To enhance the meltdown temperature of the separator, in this study, a PE separator was coated with polymers synthesized from various ethylene glycol dimethacrylate monomers. When the separator was coated with polymer synthesized from diethylene glycol dimethacrylate (DEGDMA), its shutdown temperature and meltdown temperature were increased to 142 and 155 °C, respectively. Furthermore, a slight increase in the air permeability of the separator was observed when the separator was coated with polymer synthesized from an ethanol solution containing the proper amount of DEGDMA. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900096z

Enhancement of the meltdown temperature of a lithium ion battery separator via a nanocomposite coating / S. H. Yoo in Industrial & engineering chemistry research, Vol. 48 N° 22 (Novembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 22 (Novembre 2009) . - pp. 9936–9941 Titre : Enhancement of the meltdown temperature of a lithium ion battery separator via a nanocomposite coating Type de document : texte imprimé Auteurs : S. H. Yoo, Auteur ; C. K. Kim, Auteur Année de publication : 2010 Article en page(s) : pp. 9936–9941 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Lithium  ion  battery  separator  Meltdown  temperature Résumé : In a previous study, a lithium ion battery separator was coated with polymers synthesized from various ethylene glycol dimethacrylates to enhance its meltdown temperature. The meltdown temperature of the separator was increased to 155 °C when it was coated with polymer synthesized from diethylene glycol dimethacrylate (DEGDMA). In this study, a PE separator was coated with nanocomposites composed of DEGDMA polymer and silica nanoparticles for further enhancement of the meltdown temperature. Coatings with nanocomposites were prepared via two different methods: coating the separator by reacting a methanol solution containing DEGDMA and silica nanoparticles or coating the separator by reacting with a methanol solution containing water, DEGDMA, and tetraethylorthosilicate. The formation of nanocomposite on the separator was confirmed by FT-IR, EDS, and electron microscopy. Regardless of the coating method, an increase in the meltdown temperature with a decrease in the air permeability was observed with the nanocomposite coating. The meltdown temperature of the separator was increased to 170 °C with an acceptable reduction in the air permeability when the separator was coated with composite using the latter method. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901141u [article] Enhancement of the meltdown temperature of a lithium ion battery separator via a nanocomposite coating [texte imprimé] / S. H. Yoo, Auteur ; C. K. Kim, Auteur . - 2010 . - pp. 9936–9941. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 22 (Novembre 2009) . - pp. 9936–9941 Mots-clés : Lithium  ion  battery  separator  Meltdown  temperature Résumé : In a previous study, a lithium ion battery separator was coated with polymers synthesized from various ethylene glycol dimethacrylates to enhance its meltdown temperature. The meltdown temperature of the separator was increased to 155 °C when it was coated with polymer synthesized from diethylene glycol dimethacrylate (DEGDMA). In this study, a PE separator was coated with nanocomposites composed of DEGDMA polymer and silica nanoparticles for further enhancement of the meltdown temperature. Coatings with nanocomposites were prepared via two different methods: coating the separator by reacting a methanol solution containing DEGDMA and silica nanoparticles or coating the separator by reacting with a methanol solution containing water, DEGDMA, and tetraethylorthosilicate. The formation of nanocomposite on the separator was confirmed by FT-IR, EDS, and electron microscopy. Regardless of the coating method, an increase in the meltdown temperature with a decrease in the air permeability was observed with the nanocomposite coating. The meltdown temperature of the separator was increased to 170 °C with an acceptable reduction in the air permeability when the separator was coated with composite using the latter method. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901141u

Morphology and mechanical properties of nanocomposites fabricated from organoclays and a novolac phenolic resin via melt mixing / S. G. Kang in Industrial & engineering chemistry research, Vol. 49 N° 23 (Décembre 2010) 

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