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Improvement of the compatibilization of high - impact polystyrene / magnesium hydroxide composites with partially sulfonated polystyrene as macromolecular compatibilizers / Zhen Yang in Industrial & engineering chemistry research, Vol. 51 N° 27 (Juillet 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 27 (Juillet 2012) . - pp. 9204-9212 Titre : Improvement of the compatibilization of high - impact polystyrene / magnesium hydroxide composites with partially sulfonated polystyrene as macromolecular compatibilizers Type de document : texte imprimé Auteurs : Zhen Yang, Auteur ; Chengang Zhou, Auteur ; Hu Yang, Auteur Année de publication : 2012 Article en page(s) : pp. 9204-9212 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Composite  material Résumé : The partially sulfonated polystyrene (SPS) is a very simple and easily prepared material. In this work, SPS was used for the first time as a macromolecular compatibilizer to improve the compatibilization of high-impact polystyrene (HIPS)/ magnesium hydroxide (MH) composites by self-compatibilization technology. The compatibilization effects of SPS were systematically studied by mechanical performance tests, limiting oxygen index (LOI) measurements, thermal stability analyses, and scanning electron microscopy (SEM) observation. On the basis of these experimental results, SPS was proven efficient to enhance the compatibilization of the HIPS/MH composites due to the coupling effects. The sulfonic groups of SPS could anchor onto the surface of MH particles through interaction with hydroxyl groups of MH. Meanwhile, the long alkyl chains of SPS readily entwisted with HIPS matrix. Besides, the effects of both the sulfonation degree and the content of SPS on the performance of HIPS/MH composites were investigated also. In order to obtain the best overall final performance, both of the aforementioned parameters should be controlled in a suitable range. The optimal condition in this study was 3―4.5 wt % of SPS with sulfonation degree of 24.8―35.5% in the composites. Furthermore, compared with styrene-butadiene-styrene block copolymer (SBS), a commercial compatibilizer widely used in HIPS materials, SPS exhibited better compatibilization effects but lower cost. Therefore, it could be concluded that SPS was applicable as a cost-effective compatibilizer in HIPS/MH composites. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26132255 [article] Improvement of the compatibilization of high - impact polystyrene / magnesium hydroxide composites with partially sulfonated polystyrene as macromolecular compatibilizers [texte imprimé] / Zhen Yang, Auteur ; Chengang Zhou, Auteur ; Hu Yang, Auteur . - 2012 . - pp. 9204-9212. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 27 (Juillet 2012) . - pp. 9204-9212 Mots-clés : Composite  material Résumé : The partially sulfonated polystyrene (SPS) is a very simple and easily prepared material. In this work, SPS was used for the first time as a macromolecular compatibilizer to improve the compatibilization of high-impact polystyrene (HIPS)/ magnesium hydroxide (MH) composites by self-compatibilization technology. The compatibilization effects of SPS were systematically studied by mechanical performance tests, limiting oxygen index (LOI) measurements, thermal stability analyses, and scanning electron microscopy (SEM) observation. On the basis of these experimental results, SPS was proven efficient to enhance the compatibilization of the HIPS/MH composites due to the coupling effects. The sulfonic groups of SPS could anchor onto the surface of MH particles through interaction with hydroxyl groups of MH. Meanwhile, the long alkyl chains of SPS readily entwisted with HIPS matrix. Besides, the effects of both the sulfonation degree and the content of SPS on the performance of HIPS/MH composites were investigated also. In order to obtain the best overall final performance, both of the aforementioned parameters should be controlled in a suitable range. The optimal condition in this study was 3―4.5 wt % of SPS with sulfonation degree of 24.8―35.5% in the composites. Furthermore, compared with styrene-butadiene-styrene block copolymer (SBS), a commercial compatibilizer widely used in HIPS materials, SPS exhibited better compatibilization effects but lower cost. Therefore, it could be concluded that SPS was applicable as a cost-effective compatibilizer in HIPS/MH composites. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26132255

Preparation and characterization of high - performance perfluorosulfonic acid / SiO2 nanofibers with catalytic property via electrospinning / Pei-Pei Lu in Industrial & engineering chemistry research, Vol. 51 N° 35 (Septembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 35 (Septembre 2012) . - pp. 11348-11354 Titre : Preparation and characterization of high - performance perfluorosulfonic acid / SiO2 nanofibers with catalytic property via electrospinning Type de document : texte imprimé Auteurs : Pei-Pei Lu, Auteur ; Zhen-Liang Xu, Auteur ; Hu Yang, Auteur Année de publication : 2012 Article en page(s) : pp. 11348-11354 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Catalytic  reaction  Preparation Résumé : Polymer nanofiber-supported perfluorosulfonic acid (PFSA)/SiO2 catalysts are successfully fabricated by electrospinning method from polymer/nanoparticle suspensions. This kind of catalyst has a large number of active acid sites and high specific surface area up to 85.6 m2/g. Scanning electron microscope images reveal that the catalysts present high porosity and inner-connected porous structure which varies much with SiO2 loading. Nitrogen adsorption-desorption measurements demonstrate a wide distribution of pore sizes inside the composites. Catalysts of different compositions are evaluated in esterification in a batch reactor under various conditions, and the results indicate that those of 20 wt % PFSA loading have the best activity of unit PFSA. Supporting PFSA by a nanofibrous matrix enhances liquid holdups inside the catalysts and offers accessibility of the acid sites, and therefore improves the activity of the catalysts. Moreover, these catalysts allow recovery at high percentages and regeneration with high activity. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26324783 [article] Preparation and characterization of high - performance perfluorosulfonic acid / SiO2 nanofibers with catalytic property via electrospinning [texte imprimé] / Pei-Pei Lu, Auteur ; Zhen-Liang Xu, Auteur ; Hu Yang, Auteur . - 2012 . - pp. 11348-11354. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 35 (Septembre 2012) . - pp. 11348-11354 Mots-clés : Catalytic  reaction  Preparation Résumé : Polymer nanofiber-supported perfluorosulfonic acid (PFSA)/SiO2 catalysts are successfully fabricated by electrospinning method from polymer/nanoparticle suspensions. This kind of catalyst has a large number of active acid sites and high specific surface area up to 85.6 m2/g. Scanning electron microscope images reveal that the catalysts present high porosity and inner-connected porous structure which varies much with SiO2 loading. Nitrogen adsorption-desorption measurements demonstrate a wide distribution of pore sizes inside the composites. Catalysts of different compositions are evaluated in esterification in a batch reactor under various conditions, and the results indicate that those of 20 wt % PFSA loading have the best activity of unit PFSA. Supporting PFSA by a nanofibrous matrix enhances liquid holdups inside the catalysts and offers accessibility of the acid sites, and therefore improves the activity of the catalysts. Moreover, these catalysts allow recovery at high percentages and regeneration with high activity. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26324783

Preparation of polyvinylidene fluoride (PVDF) membranes via nonsolvent induced phase Separation Process using a Tween 80 and H2O Mixture As an Additive / Ping-Yun Zhang in Industrial & engineering chemistry research, Vol. 51 N° 11 (Mars 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 11 (Mars 2012) . - pp. 4388–4396 Titre : Preparation of polyvinylidene fluoride (PVDF) membranes via nonsolvent induced phase Separation Process using a Tween 80 and H2O Mixture As an Additive Type de document : texte imprimé Auteurs : Ping-Yun Zhang, Auteur ; Hu Yang, Auteur ; Zhen-Liang Xu, Auteur Année de publication : 2012 Article en page(s) : pp. 4388–4396 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Separation  process Résumé : Polyvinylidene fluoride (PVDF) membranes were fabricated by the nonsolvent induced phase separation (NIPS) process using Tween 80 and H2O as a mixture additive from both 60 °C and room-temperature (RT) casting solution. Resultant PVDF membranes revealed improved pure water flux (PWF), enlarged mechanical properties, and well Bovine serum albumin (BSA) and Dextran rejection as a result of addition of water into the PVDF–DMAc–Tween 80 system. The improved performance was attributed to the existence of nonsolvent, which was solubilized by polar head groups of Tween 80 reverse micelle to form the water pool. Further, the interaction between polar head of surfactant and water provided a balance resistance to the interconnection between PVDF and hydrophobic chains of surfactant, which enhanced the thermodynamics stability of casting solution. During demixing process, water diffusion from the interior of casting solution, increased the precipitation rate and led to the insufficient crystallization process of polymer. Finally, the Tween 80 reverse micelle confined the movement of water in solution, making the fingerlike structure slim and confined, with the wall structure between macrovoids. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201806v [article] Preparation of polyvinylidene fluoride (PVDF) membranes via nonsolvent induced phase Separation Process using a Tween 80 and H2O Mixture As an Additive [texte imprimé] / Ping-Yun Zhang, Auteur ; Hu Yang, Auteur ; Zhen-Liang Xu, Auteur . - 2012 . - pp. 4388–4396. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 11 (Mars 2012) . - pp. 4388–4396 Mots-clés : Separation  process Résumé : Polyvinylidene fluoride (PVDF) membranes were fabricated by the nonsolvent induced phase separation (NIPS) process using Tween 80 and H2O as a mixture additive from both 60 °C and room-temperature (RT) casting solution. Resultant PVDF membranes revealed improved pure water flux (PWF), enlarged mechanical properties, and well Bovine serum albumin (BSA) and Dextran rejection as a result of addition of water into the PVDF–DMAc–Tween 80 system. The improved performance was attributed to the existence of nonsolvent, which was solubilized by polar head groups of Tween 80 reverse micelle to form the water pool. Further, the interaction between polar head of surfactant and water provided a balance resistance to the interconnection between PVDF and hydrophobic chains of surfactant, which enhanced the thermodynamics stability of casting solution. During demixing process, water diffusion from the interior of casting solution, increased the precipitation rate and led to the insufficient crystallization process of polymer. Finally, the Tween 80 reverse micelle confined the movement of water in solution, making the fingerlike structure slim and confined, with the wall structure between macrovoids. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201806v