Pub Date : 2021-01-01DOI: 10.1007/978-3-030-68472-3_7
U. Gedde, M. Hedenqvist, M. Hakkarainen, F. Nilsson, Oisik Das
{"title":"Transport Properties of Polymers","authors":"U. Gedde, M. Hedenqvist, M. Hakkarainen, F. Nilsson, Oisik Das","doi":"10.1007/978-3-030-68472-3_7","DOIUrl":"https://doi.org/10.1007/978-3-030-68472-3_7","url":null,"abstract":"","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75856123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.2174/2452271604999201123193149
Jones Wanda, Sapkota Bedanga, Simpson Brian, A. Hassan Tarig, Jeelani Shaik, R. Vijaya
Sandwich structures are progressively being used in various engineering applications due to the superior bending-stiffness-to-weight ratio of these structures. We adapted a novel technique to incorporate carbon nanotubes (CNTs) and polyhedral oligomeric silsesquioxanes (POSS) into a sandwich composite structure utilizing a sonochemical and high temperature vacuum assisted resin transfer molding technique. The objective of this work was to create a sandwich composite structure comprised of a nanophased foam core and reinforced nanophased face sheets, and to examine the thermal and mechanical properties of the structure. To prepare sandwich structure, POSS nanoparticles were sonochemically attached to CNTs and dispersed in a high temperature resin system to make the face sheet materials and also coated on expandable thermoplastic microspheres for the fabrication of foam core materials. The nanophased foam core was fabricated with POSS infused thermoplastic microspheres (Expancel) using a Tetrahedron MTP-14 programmable compression molder. The reinforced nanophased face sheet were fabricated by infusing POSS coated CNT in epoxy resin and then curing into a compression stainless steel mold. Thermal analysis of POSS-infused thermoplastic microspheres foam (TMF) showed an increase in thermal stability in both nitrogen and oxygen atmospheres, 19% increase in thermal residue were observed for 4 wt% GI-POSS TMF compared to neat TMF. Quasi-static compression results indicated significant increases (73%) in compressive modulus, and an increase (5%) in compressive strength for the 1 wt% EC-POSS/CNTs resin system. The nanophased sandwich structure constructed from the above resin system and the foam core system displayed an increase (9%) in modulus over the neat sandwich structure. The incorporation of POSS-nanofillier in the foam core and POSS-coated nanotubes in the face sheet significantly improved the thermal and mechanical properties of sandwich structure. Furthermore, the sandwich structure that was constructed from nanophased resin system showed an increase in modulus, with buckling in the foam core but no visible cracking.
{"title":"Fabrication and Mechanical Properties of POSS Coated CNTs Reinforced Expancel foam core Sandwich Structures","authors":"Jones Wanda, Sapkota Bedanga, Simpson Brian, A. Hassan Tarig, Jeelani Shaik, R. Vijaya","doi":"10.2174/2452271604999201123193149","DOIUrl":"https://doi.org/10.2174/2452271604999201123193149","url":null,"abstract":"\u0000\u0000Sandwich structures are progressively being used in various engineering applications due to the superior bending-stiffness-to-weight ratio of these structures. We adapted a novel technique to incorporate carbon nanotubes (CNTs) and polyhedral oligomeric silsesquioxanes (POSS) into a sandwich composite structure utilizing a sonochemical and high temperature vacuum assisted resin transfer molding technique.\u0000\u0000\u0000\u0000The objective of this work was to create a sandwich composite structure comprised of a nanophased foam core and reinforced nanophased face sheets, and to examine the thermal and mechanical properties of the structure. To prepare sandwich structure, POSS nanoparticles were sonochemically attached to CNTs and dispersed in a high temperature resin system to make the face sheet materials and also coated on expandable thermoplastic microspheres for the fabrication of foam core materials.\u0000\u0000\u0000\u0000The nanophased foam core was fabricated with POSS infused thermoplastic microspheres (Expancel) using a Tetrahedron MTP-14 programmable compression molder. The reinforced nanophased face sheet were fabricated by infusing POSS coated CNT in epoxy resin and then curing into a compression stainless steel mold.\u0000\u0000\u0000\u0000Thermal analysis of POSS-infused thermoplastic microspheres foam (TMF) showed an increase in thermal stability in both nitrogen and oxygen atmospheres, 19% increase in thermal residue were observed for 4 wt% GI-POSS TMF compared to neat TMF. Quasi-static compression results indicated significant increases (73%) in compressive modulus, and an increase (5%) in compressive strength for the 1 wt% EC-POSS/CNTs resin system. The nanophased sandwich structure constructed from the above resin system and the foam core system displayed an increase (9%) in modulus over the neat sandwich structure.\u0000\u0000\u0000\u0000The incorporation of POSS-nanofillier in the foam core and POSS-coated nanotubes in the face sheet significantly improved the thermal and mechanical properties of sandwich structure. Furthermore, the sandwich structure that was constructed from nanophased resin system showed an increase in modulus, with buckling in the foam core but no visible cracking.\u0000","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81834593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-31DOI: 10.2174/2452271603666190614164629
R. Mankar, W. Gurnule
Rubber or nano aluminum oxide composites may be considered as potential materials in mechanical applications because of the adaptability of polymer properties of nanometric substances. Rubber nano-composite is prepared by using the emulsion polymerization method. Mechanical properties and environmental resistance properties are evaluated for a better rubber-filler interaction. In this examination, the Raman spectroscopy and the mechanical properties of nanocomposites are based on Styrene-Butadiene rubber (SBR) and were explored within the sight of nano aluminum oxide additive. The nano-composites were prepared by mechanically mixing and utilizing two-roll mills. Nano aluminum oxide particle suspensions were added to SBR and the abrasion and spectral properties were overviewed. Nano aluminum oxide, 2, 2’- dithiobis, tetramethyl thiuram disulfide, N, N’- Diphenyl P- phenylenediamine and SBR latex were used for analysis. SBR nano-composite was obtained by using the emulsion polymerization method. Mechanical test outcomes demonstrated the improvement in tensile strength, elongation, and tear resistance. Abrasion test results demonstrated that nano aluminum oxide particles could improve the abrasion resistance of SBR matrix because of the good properties of nano aluminum oxide particles. The strengthening capacity of the fillers resulted in noteworthy upgrades in the properties of polymer framework at extremely low filler loadings when contrasted with conventional fillers. In this work, we concentrate on Raman spectroscopy and mechanical properties by including filler content within a low loading amount. The collection idea of the combined rubber nano-composite was built up by using scanning electron microscopy (SEM). The impact of nanoparticles in the polymer network has been assessed for the SBR-nano aluminum oxide from the TEM investigation. Thermogravimetric analysis (TGA and DTA) was also examined. Ozone resistance was studied to elucidate periodic observations of the surface of samples, which were made for crack initiation. The samples were exposed for a longer time. Flame resistance was studied to measure the ease of extinction of a flame and four ratings were possible, depending upon the burning time and the presence of flaming drips. The present study highlights the emulsion polymerization method, where the environmental resistance performance of rubber nano-composites is found to be improved and the thermal and mechanical properties are also enhanced.
{"title":"Synthesis, Characterization, Environmental Properties and Mechanical Studies of SBR-Nano Aluminum Oxide Composites","authors":"R. Mankar, W. Gurnule","doi":"10.2174/2452271603666190614164629","DOIUrl":"https://doi.org/10.2174/2452271603666190614164629","url":null,"abstract":"\u0000\u0000Rubber or nano aluminum oxide composites may be considered as potential\u0000materials in mechanical applications because of the adaptability of polymer properties of nanometric\u0000substances. Rubber nano-composite is prepared by using the emulsion polymerization method. Mechanical\u0000properties and environmental resistance properties are evaluated for a better rubber-filler interaction.\u0000\u0000\u0000\u0000In this examination, the Raman spectroscopy and the mechanical properties of nanocomposites\u0000are based on Styrene-Butadiene rubber (SBR) and were explored within the sight of nano\u0000aluminum oxide additive. The nano-composites were prepared by mechanically mixing and utilizing\u0000two-roll mills. Nano aluminum oxide particle suspensions were added to SBR and the abrasion and\u0000spectral properties were overviewed.\u0000\u0000\u0000\u0000Nano aluminum oxide, 2, 2’- dithiobis, tetramethyl thiuram disulfide, N,\u0000N’- Diphenyl P- phenylenediamine and SBR latex were used for analysis. SBR nano-composite was\u0000obtained by using the emulsion polymerization method.\u0000\u0000\u0000\u0000Mechanical test outcomes demonstrated the improvement in tensile strength, elongation,\u0000and tear resistance. Abrasion test results demonstrated that nano aluminum oxide particles could improve\u0000the abrasion resistance of SBR matrix because of the good properties of nano aluminum oxide\u0000particles. The strengthening capacity of the fillers resulted in noteworthy upgrades in the properties\u0000of polymer framework at extremely low filler loadings when contrasted with conventional fillers. In\u0000this work, we concentrate on Raman spectroscopy and mechanical properties by including filler content\u0000within a low loading amount. The collection idea of the combined rubber nano-composite was\u0000built up by using scanning electron microscopy (SEM). The impact of nanoparticles in the polymer\u0000network has been assessed for the SBR-nano aluminum oxide from the TEM investigation. Thermogravimetric\u0000analysis (TGA and DTA) was also examined. Ozone resistance was studied to elucidate\u0000periodic observations of the surface of samples, which were made for crack initiation. The samples\u0000were exposed for a longer time. Flame resistance was studied to measure the ease of extinction of a\u0000flame and four ratings were possible, depending upon the burning time and the presence of flaming\u0000drips.\u0000\u0000\u0000\u0000The present study highlights the emulsion polymerization method, where the environmental\u0000resistance performance of rubber nano-composites is found to be improved and the thermal\u0000and mechanical properties are also enhanced.\u0000","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78845424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-31DOI: 10.2174/2452271603666181228120700
V. G. Shevchenko, P. M. Nedorezova, A. Ozerin
The paper describes the types and electrical properties of polymer nanocomposites containing carbon allotropes.Direct current conductivity, conduction in percolation systems, conduction mechanisms and factors controlling conductivity and percolation parameters are considered.The dielectric properties of polymer nanocomposites are presented, and experimental methods and methods for analyzing the results have also been described. An analysis of the data on ac electrical conductivity, including the contribution of nanofiller - interfacial polarization is presented. Special consideration is given to the role of nanocarbons as dielectric probes.The microwave properties of polymer nanocomposites, their use to estimate the distribution of nanofiller in the matrix, as well as practical applications for shielding and absorption of electromagnetic radiation have been analyzed.The use of carbon allotropes nanoparticles as fillers with high electrical conductivity provides polymer composites with useful electrical properties, including the ability to absorb highfrequency electromagnetic radiation.
{"title":"Dielectric Properties of Polymer Composites with Nanocarbon Allotropes","authors":"V. G. Shevchenko, P. M. Nedorezova, A. Ozerin","doi":"10.2174/2452271603666181228120700","DOIUrl":"https://doi.org/10.2174/2452271603666181228120700","url":null,"abstract":"The paper describes the types and electrical properties of polymer nanocomposites containing carbon allotropes.Direct current conductivity, conduction in percolation systems, conduction mechanisms and factors controlling conductivity and percolation parameters are considered.The dielectric properties of polymer nanocomposites are presented, and experimental methods and methods for analyzing the results have also been described. An analysis of the data on ac electrical conductivity, including the contribution of nanofiller - interfacial polarization is presented. Special consideration is given to the role of nanocarbons as dielectric probes.The microwave properties of polymer nanocomposites, their use to estimate the distribution of nanofiller in the matrix, as well as practical applications for shielding and absorption of electromagnetic radiation have been analyzed.The use of carbon allotropes nanoparticles as fillers with high electrical conductivity provides polymer composites with useful electrical properties, including the ability to absorb highfrequency electromagnetic radiation.","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86555063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-31DOI: 10.2174/2452271603666190822091208
Anand Mahalwar
Surface modification is the modification of the surface (either of carrier, drug or targeting moiety) by which solubility, opsonization, adhesion, longer circulation, and bioconjugation of an object can be achieved. Techniques which modify surface properties of carriers, drugs, ligands, excipients, coating materials, etc. by introducing random, non-specific groups or selected, specific groups can be used to alter the surface properties of the object. Through this review, a small attempt is made to understand the surface modification techniques. In this review, several methods (surface modification by solid dispersion technique, surfactants, polaxamer and polaxamine coating, PEG (polyethylene glycol), Vitamin E, Dextran derivatives, Chitosan coating, chemicals, gas and through layer by layer techniques) are discussed for surface modification. A concise review was done to explore the availability of techniques and agents available to introduce a specific group into the object.
{"title":"Surface Modification: Approaches and Utilities","authors":"Anand Mahalwar","doi":"10.2174/2452271603666190822091208","DOIUrl":"https://doi.org/10.2174/2452271603666190822091208","url":null,"abstract":"\u0000\u0000Surface modification is the modification of the surface (either of carrier, drug or targeting\u0000moiety) by which solubility, opsonization, adhesion, longer circulation, and bioconjugation of an object\u0000can be achieved.\u0000\u0000\u0000\u0000Techniques which modify surface properties of carriers, drugs, ligands, excipients, coating materials,\u0000etc. by introducing random, non-specific groups or selected, specific groups can be used to alter the\u0000surface properties of the object. Through this review, a small attempt is made to understand the surface\u0000modification techniques. In this review, several methods (surface modification by solid dispersion\u0000technique, surfactants, polaxamer and polaxamine coating, PEG (polyethylene glycol), Vitamin\u0000E, Dextran derivatives, Chitosan coating, chemicals, gas and through layer by layer techniques) are\u0000discussed for surface modification. A concise review was done to explore the availability of techniques\u0000and agents available to introduce a specific group into the object.\u0000","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82346196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-31DOI: 10.2174/2452271603666190307161921
Lu Ping
The addition of inorganic nano dioxide (TiO2) and alumina (Al2O3) particles into the organic polymer material Polyvinylidene Fluoride (PVDF) can enhance the composite membranes’ hydrophilicity and anti-pollution capacity in the water treatment process. The study aimed to investigate thermodynamic and kinetic effects of the inorganic nanoparticles on composite membrane in the membrane forming process. The turbid point titration method was adopted to determine casting solution phase separation point of the system and draw ternary phase diagrams. Ternary system phase diagrams were used to investigate the thermodynamic effects of nanoparticles on the membrane forming process. UV spectrophotometer transmittance decline curves of the casting solution system added different amounts of nanoparticles were measured in order to investigate the kinetic effects of nanoparticles in the membrane forming process. The results show that nanoparticles have a very high specific surface area, which can make strong adsorption of PVDF polymer chain and reduce the cohesive energy of the polymer in the casting solution. The membrane forming system is more prone to phase separation, thereby reducing the sedimentation values of the phase separation point. The casting solution system becomes unstable thermodynamically. The decreasing trend casting solution system and precipitation values is obvious in the range of 1% to 3% nanoparticles content and this trend weakens when nanoparticles content is 4%. Nanoparticles can decrease the ability of non-solvent to accommodate in the casting solution and make membrane form in smaller non-solvent concentration. The hydrophilic nanoparticles in the casting solution can affect mass transfer resistance of the solvent and non-solvent and augment mass transfer driving force for mutual diffusion of the solvent and non-solvent thus shortening the membrane forming time from the casting solution being immersed in the gelation bath for membrane formation. In the system with PVP as pore-forming agent, the process takes about 800s without nanoparticles addition and about 600s to complete the process after adding the nanoparticles. The addition of nanoparticles reduces the cohesive energy of the polymer in the casting solution, the casting solution becomes unstable in thermodynamics; The addition of nanoparticles increases the mass transfer force by bidirectional diffusion of solvent and non-solvent in the casting solution.
{"title":"The Investigation of Thermodynamic and Kinetic Effects in TiO2/Al2O3/ PVDF Composite Membrane Forming Process","authors":"Lu Ping","doi":"10.2174/2452271603666190307161921","DOIUrl":"https://doi.org/10.2174/2452271603666190307161921","url":null,"abstract":"\u0000\u0000The addition of inorganic nano dioxide (TiO2) and alumina (Al2O3) particles\u0000into the organic polymer material Polyvinylidene Fluoride (PVDF) can enhance the composite membranes’\u0000hydrophilicity and anti-pollution capacity in the water treatment process.\u0000\u0000\u0000\u0000The study aimed to investigate thermodynamic and kinetic effects of the inorganic nanoparticles\u0000on composite membrane in the membrane forming process.\u0000\u0000\u0000\u0000The turbid point titration method was adopted to determine casting solution phase separation\u0000point of the system and draw ternary phase diagrams. Ternary system phase diagrams were used\u0000to investigate the thermodynamic effects of nanoparticles on the membrane forming process. UV\u0000spectrophotometer transmittance decline curves of the casting solution system added different\u0000amounts of nanoparticles were measured in order to investigate the kinetic effects of nanoparticles in\u0000the membrane forming process.\u0000\u0000\u0000\u0000The results show that nanoparticles have a very high specific surface area, which can make\u0000strong adsorption of PVDF polymer chain and reduce the cohesive energy of the polymer in the casting\u0000solution. The membrane forming system is more prone to phase separation, thereby reducing the\u0000sedimentation values of the phase separation point. The casting solution system becomes unstable\u0000thermodynamically. The decreasing trend casting solution system and precipitation values is obvious\u0000in the range of 1% to 3% nanoparticles content and this trend weakens when nanoparticles content is\u00004%. Nanoparticles can decrease the ability of non-solvent to accommodate in the casting solution and\u0000make membrane form in smaller non-solvent concentration. The hydrophilic nanoparticles in the\u0000casting solution can affect mass transfer resistance of the solvent and non-solvent and augment mass\u0000transfer driving force for mutual diffusion of the solvent and non-solvent thus shortening the membrane\u0000forming time from the casting solution being immersed in the gelation bath for membrane formation.\u0000In the system with PVP as pore-forming agent, the process takes about 800s without nanoparticles\u0000addition and about 600s to complete the process after adding the nanoparticles.\u0000\u0000\u0000\u0000The addition of nanoparticles reduces the cohesive energy of the polymer in the casting\u0000solution, the casting solution becomes unstable in thermodynamics; The addition of nanoparticles increases\u0000the mass transfer force by bidirectional diffusion of solvent and non-solvent in the casting solution.\u0000","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82735374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-31DOI: 10.2174/245227160302191010142323
Jim Low
Prof. Low obtained his B. Eng (Hons) and Ph.D. degrees in Materials Engineering from Monash University prior to taking up lecturer positions first at Auckland University and then Curtin at University. He won the B.H.P, Nylex, and Alcoa prizes during his undergraduate years and was awarded with a Monash postgraduate research scholarship in 1983. He was awarded with a Visiting Professorship by the Japanese Ministry of Education to work with Prof. Niihara at Osaka University in 1995/1996. He is a Fellow of the Australian Ceramic Society and has served on the editorial board of the Journal of Australian Ceramic Society and the Journal of Ceramics. He is also the recipient of the prestigious 1996 Joint Australian Ceramic Society/Ceramic Society of Japan Ceramic Award for excellence in ceramics research. His research interests include polymer composites, nanotechnology, toughening and failure micromechanics. More recently, his research focuses on:
{"title":"Meet Our Regional Editor","authors":"Jim Low","doi":"10.2174/245227160302191010142323","DOIUrl":"https://doi.org/10.2174/245227160302191010142323","url":null,"abstract":"Prof. Low obtained his B. Eng (Hons) and Ph.D. degrees in Materials Engineering from Monash University prior to taking up lecturer positions first at Auckland University and then Curtin at University. He won the B.H.P, Nylex, and Alcoa prizes during his undergraduate years and was awarded with a Monash postgraduate research scholarship in 1983. He was awarded with a Visiting Professorship by the Japanese Ministry of Education to work with Prof. Niihara at Osaka University in 1995/1996. He is a Fellow of the Australian Ceramic Society and has served on the editorial board of the Journal of Australian Ceramic Society and the Journal of Ceramics. He is also the recipient of the prestigious 1996 Joint Australian Ceramic Society/Ceramic Society of Japan Ceramic Award for excellence in ceramics research. His research interests include polymer composites, nanotechnology, toughening and failure micromechanics. More recently, his research focuses on:","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90886409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-31DOI: 10.2174/2452271603666190307161415
Reza Haddad, M. D. Telgerd, H. Hadi, M. Sadeghinia
Polyacrylonitrile/Mo132 composite nanofibers mats was synthesized by an electrospinning technique using PAN and giant ball nano-polyoxomolybdateMo132. The nanocluster Mo132 was mixed with PAN solution and then electrospun to produce bead-free nanofibers. The aim of this study is to evaluate the adsorption ability of electrospun composite nanofibers against sulfur mustard stimulants and assess the possibility of using the electrospun nanofibers as protective membranes in chemical masks and warfare clothing. Adsorption of sulfur mustard stimulants was investigated on the surface of PAN nanofibers embedded with keplerate nano-polyoxomolybdate. In order to study the 2-CEES adsorption ability, the prepared PAN/Mo132 nanofibers composite was further prepared and exposed to 2-CEES solution. The surface morphology and other properties of the PAN/Mo132 nanofibers composite were characterized by various techniques, including SEM, TEM, FT-IR, UV-Vis. SEM images which showed that the average diameter of the fibers was found to be between 100-120 nm. The adsorption efficiency of PAN/Mo132 composite in adsorption of 2-CEES was obtained 89% after 7h at room temperature. The results showed that composite nanofibers PAN/Mo132 will have a good ability as protective clothing and chemical masks against chemical warfare agents. PAN/Mo132 nanofibers were prepared by electrospinning method. The leaching of Mo132 from the nanofibers was not observed, meaning that the catalyst had excellent stability and could be used as a heterogeneous structure against the adsorption of sulfur mustard stimulant at room temperature. This composite nanofibers membrane exhibited good performance to adsorb 2-CEES in comparison with pure PAN. The adsorption rate of 2-CEES increases with increasing the amount of Mo132 embedded in the PAN nanofibers.
{"title":"Fabrication of a Novel Electrospun Polyacrylonitrile/Giant Ball {Mo132} Composite Nanofibrous Mats in Adsorption of 2-CEES","authors":"Reza Haddad, M. D. Telgerd, H. Hadi, M. Sadeghinia","doi":"10.2174/2452271603666190307161415","DOIUrl":"https://doi.org/10.2174/2452271603666190307161415","url":null,"abstract":"\u0000\u0000Polyacrylonitrile/Mo132 composite nanofibers mats was synthesized by an\u0000electrospinning technique using PAN and giant ball nano-polyoxomolybdateMo132. The nanocluster\u0000Mo132 was mixed with PAN solution and then electrospun to produce bead-free nanofibers. The\u0000aim of this study is to evaluate the adsorption ability of electrospun composite nanofibers against sulfur\u0000mustard stimulants and assess the possibility of using the electrospun nanofibers as protective\u0000membranes in chemical masks and warfare clothing. Adsorption of sulfur mustard stimulants was investigated\u0000on the surface of PAN nanofibers embedded with keplerate nano-polyoxomolybdate.\u0000\u0000\u0000\u0000In order to study the 2-CEES adsorption ability, the prepared PAN/Mo132 nanofibers\u0000composite was further prepared and exposed to 2-CEES solution. The surface morphology and other\u0000properties of the PAN/Mo132 nanofibers composite were characterized by various techniques, including\u0000SEM, TEM, FT-IR, UV-Vis. SEM images which showed that the average diameter of the fibers\u0000was found to be between 100-120 nm.\u0000\u0000\u0000\u0000The adsorption efficiency of PAN/Mo132 composite in adsorption of 2-CEES was obtained\u000089% after 7h at room temperature. The results showed that composite nanofibers\u0000PAN/Mo132 will have a good ability as protective clothing and chemical masks against chemical\u0000warfare agents.\u0000\u0000\u0000\u0000PAN/Mo132 nanofibers were prepared by electrospinning method. The leaching of\u0000Mo132 from the nanofibers was not observed, meaning that the catalyst had excellent stability and\u0000could be used as a heterogeneous structure against the adsorption of sulfur mustard stimulant at room\u0000temperature. This composite nanofibers membrane exhibited good performance to adsorb 2-CEES in\u0000comparison with pure PAN. The adsorption rate of 2-CEES increases with increasing the amount of\u0000Mo132 embedded in the PAN nanofibers.\u0000","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78511847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-31DOI: 10.2174/2452271602666181114094536
J. C. Ramírez, Dimas Medina, F. López-Carrasquero, R. Contreras
The synthesis of the aliphatic polyesters obtained by the ring opening polymerization has been achieved using as initiators a large amount of organometallic compounds derivative from: Alkali metals, alkaline earth metals, transition metals and lanthanide metals. Of all these compounds, the lanthanide derivatives have acquired great importance in the synthesis of aliphatic polyesters, since these show a greater catalytic activity and also can provide polymer with characteristics that will be very useful in the design of biomaterials. It was proposed the synthesis of poly(L-lactida) (PL-LA) through a ring opening polymerization process of L-lactide initiated with samarium(III) acetate (Sm(OAc)3) under solvent-free melt conditions. The influence of different parameters of reaction, such as temperature, time, molar ratio monomer to initiator, on typical variables of polymers, e.g., conversion, dispersity, and molar mass, were analyzed. All polymerizations were carried out under solvent-free melt conditions in ampoules-like flasks, equipped with a magnetic stirrer. The obtained polyesters were characterized by size exclusion chromatography (SEC) and 1H-NMR. The Sm(OAc)3 induces the polymerization of L-LA at high conversion, and produce polyesters with number-average molecular weights of 1.00 x 103 to 30.00 x 103 Dalton. The 1H-NMR analysis indicates a typical polymerization mechanism of coordination-insertion, with a breakdown of the acyl-oxygen bond of the L-LA. Sm(OAc)3 was an effective initiator for the ring-opening polymerization of L-LA. SEC chromatography showed that, at high temperatures and prolonged reaction times, the molar mass of the polyester decreases, which is associated with the transesterification collateral reactions that occur during the polymerization process.
{"title":"Ring-Opening Polymerization of L-lactide Initiated by Samarium(III) Acetate","authors":"J. C. Ramírez, Dimas Medina, F. López-Carrasquero, R. Contreras","doi":"10.2174/2452271602666181114094536","DOIUrl":"https://doi.org/10.2174/2452271602666181114094536","url":null,"abstract":"\u0000\u0000 The synthesis of the aliphatic polyesters obtained by the ring opening\u0000polymerization has been achieved using as initiators a large amount of organometallic compounds\u0000derivative from: Alkali metals, alkaline earth metals, transition metals and lanthanide metals. Of all\u0000these compounds, the lanthanide derivatives have acquired great importance in the synthesis of aliphatic\u0000polyesters, since these show a greater catalytic activity and also can provide polymer with\u0000characteristics that will be very useful in the design of biomaterials.\u0000\u0000\u0000\u0000It was proposed the synthesis of poly(L-lactida) (PL-LA) through a ring opening polymerization\u0000process of L-lactide initiated with samarium(III) acetate (Sm(OAc)3) under solvent-free melt\u0000conditions. The influence of different parameters of reaction, such as temperature, time, molar ratio\u0000monomer to initiator, on typical variables of polymers, e.g., conversion, dispersity, and molar mass,\u0000were analyzed.\u0000\u0000\u0000\u0000 All polymerizations were carried out under solvent-free melt conditions in ampoules-like\u0000flasks, equipped with a magnetic stirrer. The obtained polyesters were characterized by size exclusion\u0000chromatography (SEC) and 1H-NMR.\u0000\u0000\u0000\u0000 The Sm(OAc)3 induces the polymerization of L-LA at high conversion, and produce polyesters\u0000with number-average molecular weights of 1.00 x 103 to 30.00 x 103 Dalton. The 1H-NMR analysis\u0000indicates a typical polymerization mechanism of coordination-insertion, with a breakdown of the\u0000acyl-oxygen bond of the L-LA.\u0000\u0000\u0000\u0000Sm(OAc)3 was an effective initiator for the ring-opening polymerization of L-LA. SEC\u0000chromatography showed that, at high temperatures and prolonged reaction times, the molar mass of\u0000the polyester decreases, which is associated with the transesterification collateral reactions that occur\u0000during the polymerization process.\u0000","PeriodicalId":10768,"journal":{"name":"Current Applied Polymer Science","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80023552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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