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Editorial overview: Materials engineering: Coatings and interfaces
COCHE-294; NO. OF PAGES 2
Available online at www.sciencedirect.com
ScienceDirect Editorial overview: Materials engineering: Coatings and interfaces Thein Kyu and JA Sekhar Current Opinion in Chemical Engineering 2016, 11:xx–yy
http://dx.doi.org/10.1016/j.coche.2016.02.001 2211-3398/# 2016 Elsevier Ltd. All rights reserved.
Thein Kyu Department of Polymer Engineering, University of Akron, USA e-mail: [email protected] Thein Kyu is currently a Distinguished Professor at the Department of Polymer Engineering, University of Akron. His research interest encompasses thermodynamic phase equilibria and kinetics of phase separation in polymer blends, polymerization-induced phase separation and phase transitions in crystalline and liquid crystalline polymers, non-linear dynamics of pattern formation, electro-optics of dispersed liquid crystal and photonic crystals, selfpropelled crystal motion, ion-exchange membranes, proton fuel cells, and solid-state polymer lithium ion battery.
JA Sekhar Institute of Thermodynamics and Design, Cincinnati, OH 45215, USA e-mail: [email protected] JA Sekhar (Jai) is a Professor Emeritus of the University of Cincinnati, Department of Mechanical and Materials Engineering. His research interests span interfacial thermodynamics of solidification, high temperature process engineering, nanotechnology and the understanding of business patterns. He has considerable management experience in materials technology companies, with both technical innovation and business management. His hobbies include flying airplanes. Currently he is establishing the Institute of Thermodynamics and Design. He manages two engineering companies with global product offerings in transformative, energyefficient materials and systems, manufactured in USA.
Following the successful series [1–3] of materials engineering related articles in this journal, the current volume for 2016 entails emerging trends in coatings and interfaces of hard and soft materials. In the soft matter of polymers and biopolymers, there are several review articles encompassing materials synthesis for organic–inorganic hybrid coating via sol–gel reaction for protective coating for corrosion and fire retardant coating, surface functionalization of carbon nanotube and graphene sheets for carbonaceous anode applications in secondary rechargeable lithium ion batteries, molecular simulation and modeling on absorption behavior of biomacromolecules on various surfaces, all the way to biointerfaces including organic coating of hydrophobic nanoparticles in polymer composites using hydrophilic polymers for drug delivery, and strategies for silver incorporation in montmorillonite clay via cationic exchange reactions to afford prolonged antibacterial activity. Given the broadness of this emerging field, it is not possible to cover it fully. However, some of these topics are undoubtedly appealing and meaningful to general audience and some specialists. Articles on hard coatings and materials that are important in the automotive, consumer packaging, medical and aerospace sectors are included in this journal volume. The section contains an article by Zvonkina and Soucek, who demonstrate various synthesis strategies of designing a so-called ‘ceramer’ (meaning ceramicpolymer) via sol–gel reaction based on photopolymerization approach for protective and fire retardant coatings. The authors elaborate on possible strategies of coating by taking advantage of a phenomenon called surface enrichment during reaction-induced phase separation in mixtures of reactive inorganic and organic molecules driven by thermodynamics/kinetics and photopolymerization kinetics. This article provides a future perspective on stratification phenomenon to render the formation of bi-layers such as siloxane and fluoro-polymer containing acrylate derivatives, the interface of which can be stabilized by their inorganic– organic copolymers. Although such processing techiques are common to hard cascade coatings they are relatively new in this soft matter context. Medical applications for regenerative structures, and interfaces with and between engineering coatings and substrates is extremely topical. The spatial and temporal control of cell-adhesion as a function of the stimulus and/or surface conditions is reviewed by Ross Andrews et al. The topographic connection with bioprinting cell clusters at low-resolution as reservoirs, with 2D or 3D polymer micro patterns is discussed in this brief review. The article by Tsukahara and Adachi is aimed at surface modification of carbonaceous materials as a means of improving solid-state lithium ion
www.sciencedirect.com
Current Opinion in Chemical Engineering 2016, 11:1–2
Please cite this article in press as: Kyu T, Sekhar JA: Editorial overview: Materials engineering: Coatings and interfaces, Curr Opin Chem Eng (2016), http://dx.doi.org/10.1016/j.coche.2016.02.001
COCHE-294; NO. OF PAGES 2
2 Materials Engineering
battery and/or supercapacitor. The materials of choice for anode were graphene sheet and carbon nanotube (CNT). The surface functionalization of CNTs by anionic approach afford controlled molecular weight, functionality, and architecture. Anionic approach enabled variety of covalent modification with less damage. Anionic approach allowed direct polyethylene glycol (PEG) grafting on CNT surface, which can improve interface compatibility with solid polymer electrolyte membranes containing PEG. Another material of choice is the graphene sheet as anode material in energy conversion and storage devices. Potential applications include solar cells, fuel cells, supercapacitors, and secondary ion batteries. By virtue of large surface area, high mechanical strength, excellent electrical and thermal conductivity, graphene is anticipated to afford a wide range of potential energy conversion applications. The article by Dai and co-workers gives an overview on large scale production of edge-selectively functionalized graphene nanoplatelets by mechanochemical ball-milling. This approach is capable of producing high-quality edge-selectively functionalized graphene nanoplatelets in large scale and at a low-cost and ecofriendly manner. This section was further enriched by the modeling and molecular simulation of protein absorption behavior on various surfaces and interfaces. The contribution by Heinz elegantly described a complex interfacial phenomenon from the molecular modeling perspective, covering nanostructured forms of silicates, glasses, and oxide surfaces for therapeutics, catalysts, and composites. It was emphasized that modeling of the inorganic–organic interfaces based on force fields and molecular models at the 1– 100 nm scale has recently become more viable that includes oxide surface chemistry and pH dependent ionization. This article concludes with the capabilities of chemically realistic bonded potentials to predict surface properties and specific binding of biomolecules. From an experimental point of view, design of therapeutic nanoparticle system via surface modification was introduce by Lopez et al. to enhance colloidal stability of hydrophobic biopolymer such as poly(lactic acid) (PLA) nanoparticles with the aid of hydrophilic polyethylene glycol (PEG). Their focus was on the delivery of
Current Opinion in Chemical Engineering 2016, 11:1–2
mucosal drugs based on PEG modified PLA nanoparticulates through the gastrointestinal track. Possible mechanisms of mucoadhesion and mucin/polymer interactions were discussed. The section contains an article by Giraldo and co-workers which covers surface modification of montmorillonite (MMT) clays by silver incorporation to render antibacterial activity. The authors introduced synthesis strategies via cationic exchange reactions at the bio-clay interface of nano-platelets. The authors suggest the use of surfactants and ionic liquids that promote MMT exfoliation to allow a higher specific area for silver ions adsorption. The article concludes with possible strategies to prolong the antibacterial activity of silver species in the MMT nano-clays. In keeping with very current concerns regarding the safety of drinking water, Changseok Han et al., from the USEPA and a US high-school, present an excellent update on nano-particle surface coatings that contain TiO2 photocatalysts. An article that describes the critically important properties of oxide, hard nitride and oxy-nitride coatings for the automotive sector is the focus of Sundararajan et al. This article extends predictions made about Plasma and Plasma like processes that were predicted as being significant to materials engineering for the next century [3]. Authors, Igor Filiminov and Alex Poletaev review a few combustion microkinetic models for obtaining various scales of microstructure. Last but not least, we would like to thank all authors and reviewers who graciously contributed their precious time and efforts to ensure high quality of the articles. The professional help from the editorial team of Elsevier, especially Ms. Patricia Hudson (Patries) and Justyna Kasprzycka, is gratefully acknowledged; without their help, the timely completion of this section would not have been possible.
References 1.
Kyu T: Curr Opin Chem Eng2013, 2:60 http://dx.doi.org/10.1016/ j.coche.2012.11.003.
2.
Kyu T, Sekhar JA: Curr Opin Chem Eng2014, 3:99 http:// dx.doi.org/10.1016/j.coche.2013.12.005.
3.
Sekhar JA: Curr Opin Chem Eng2015, 7:vii http://dx.doi.org/ 10.1016/j.coche.2014.12.002.
www.sciencedirect.com
Please cite this article in press as: Kyu T, Sekhar JA: Editorial overview: Materials engineering: Coatings and interfaces, Curr Opin Chem Eng (2016), http://dx.doi.org/10.1016/j.coche.2016.02.001
Available online at www.sciencedirect.com
ScienceDirect Editorial overview: Materials engineering: Coatings and interfaces Thein Kyu and JA Sekhar Current Opinion in Chemical Engineering 2016, 11:xx–yy
http://dx.doi.org/10.1016/j.coche.2016.02.001 2211-3398/# 2016 Elsevier Ltd. All rights reserved.
Thein Kyu Department of Polymer Engineering, University of Akron, USA e-mail: [email protected] Thein Kyu is currently a Distinguished Professor at the Department of Polymer Engineering, University of Akron. His research interest encompasses thermodynamic phase equilibria and kinetics of phase separation in polymer blends, polymerization-induced phase separation and phase transitions in crystalline and liquid crystalline polymers, non-linear dynamics of pattern formation, electro-optics of dispersed liquid crystal and photonic crystals, selfpropelled crystal motion, ion-exchange membranes, proton fuel cells, and solid-state polymer lithium ion battery.
JA Sekhar Institute of Thermodynamics and Design, Cincinnati, OH 45215, USA e-mail: [email protected] JA Sekhar (Jai) is a Professor Emeritus of the University of Cincinnati, Department of Mechanical and Materials Engineering. His research interests span interfacial thermodynamics of solidification, high temperature process engineering, nanotechnology and the understanding of business patterns. He has considerable management experience in materials technology companies, with both technical innovation and business management. His hobbies include flying airplanes. Currently he is establishing the Institute of Thermodynamics and Design. He manages two engineering companies with global product offerings in transformative, energyefficient materials and systems, manufactured in USA.
Following the successful series [1–3] of materials engineering related articles in this journal, the current volume for 2016 entails emerging trends in coatings and interfaces of hard and soft materials. In the soft matter of polymers and biopolymers, there are several review articles encompassing materials synthesis for organic–inorganic hybrid coating via sol–gel reaction for protective coating for corrosion and fire retardant coating, surface functionalization of carbon nanotube and graphene sheets for carbonaceous anode applications in secondary rechargeable lithium ion batteries, molecular simulation and modeling on absorption behavior of biomacromolecules on various surfaces, all the way to biointerfaces including organic coating of hydrophobic nanoparticles in polymer composites using hydrophilic polymers for drug delivery, and strategies for silver incorporation in montmorillonite clay via cationic exchange reactions to afford prolonged antibacterial activity. Given the broadness of this emerging field, it is not possible to cover it fully. However, some of these topics are undoubtedly appealing and meaningful to general audience and some specialists. Articles on hard coatings and materials that are important in the automotive, consumer packaging, medical and aerospace sectors are included in this journal volume. The section contains an article by Zvonkina and Soucek, who demonstrate various synthesis strategies of designing a so-called ‘ceramer’ (meaning ceramicpolymer) via sol–gel reaction based on photopolymerization approach for protective and fire retardant coatings. The authors elaborate on possible strategies of coating by taking advantage of a phenomenon called surface enrichment during reaction-induced phase separation in mixtures of reactive inorganic and organic molecules driven by thermodynamics/kinetics and photopolymerization kinetics. This article provides a future perspective on stratification phenomenon to render the formation of bi-layers such as siloxane and fluoro-polymer containing acrylate derivatives, the interface of which can be stabilized by their inorganic– organic copolymers. Although such processing techiques are common to hard cascade coatings they are relatively new in this soft matter context. Medical applications for regenerative structures, and interfaces with and between engineering coatings and substrates is extremely topical. The spatial and temporal control of cell-adhesion as a function of the stimulus and/or surface conditions is reviewed by Ross Andrews et al. The topographic connection with bioprinting cell clusters at low-resolution as reservoirs, with 2D or 3D polymer micro patterns is discussed in this brief review. The article by Tsukahara and Adachi is aimed at surface modification of carbonaceous materials as a means of improving solid-state lithium ion
www.sciencedirect.com
Current Opinion in Chemical Engineering 2016, 11:1–2
Please cite this article in press as: Kyu T, Sekhar JA: Editorial overview: Materials engineering: Coatings and interfaces, Curr Opin Chem Eng (2016), http://dx.doi.org/10.1016/j.coche.2016.02.001
COCHE-294; NO. OF PAGES 2
2 Materials Engineering
battery and/or supercapacitor. The materials of choice for anode were graphene sheet and carbon nanotube (CNT). The surface functionalization of CNTs by anionic approach afford controlled molecular weight, functionality, and architecture. Anionic approach enabled variety of covalent modification with less damage. Anionic approach allowed direct polyethylene glycol (PEG) grafting on CNT surface, which can improve interface compatibility with solid polymer electrolyte membranes containing PEG. Another material of choice is the graphene sheet as anode material in energy conversion and storage devices. Potential applications include solar cells, fuel cells, supercapacitors, and secondary ion batteries. By virtue of large surface area, high mechanical strength, excellent electrical and thermal conductivity, graphene is anticipated to afford a wide range of potential energy conversion applications. The article by Dai and co-workers gives an overview on large scale production of edge-selectively functionalized graphene nanoplatelets by mechanochemical ball-milling. This approach is capable of producing high-quality edge-selectively functionalized graphene nanoplatelets in large scale and at a low-cost and ecofriendly manner. This section was further enriched by the modeling and molecular simulation of protein absorption behavior on various surfaces and interfaces. The contribution by Heinz elegantly described a complex interfacial phenomenon from the molecular modeling perspective, covering nanostructured forms of silicates, glasses, and oxide surfaces for therapeutics, catalysts, and composites. It was emphasized that modeling of the inorganic–organic interfaces based on force fields and molecular models at the 1– 100 nm scale has recently become more viable that includes oxide surface chemistry and pH dependent ionization. This article concludes with the capabilities of chemically realistic bonded potentials to predict surface properties and specific binding of biomolecules. From an experimental point of view, design of therapeutic nanoparticle system via surface modification was introduce by Lopez et al. to enhance colloidal stability of hydrophobic biopolymer such as poly(lactic acid) (PLA) nanoparticles with the aid of hydrophilic polyethylene glycol (PEG). Their focus was on the delivery of
Current Opinion in Chemical Engineering 2016, 11:1–2
mucosal drugs based on PEG modified PLA nanoparticulates through the gastrointestinal track. Possible mechanisms of mucoadhesion and mucin/polymer interactions were discussed. The section contains an article by Giraldo and co-workers which covers surface modification of montmorillonite (MMT) clays by silver incorporation to render antibacterial activity. The authors introduced synthesis strategies via cationic exchange reactions at the bio-clay interface of nano-platelets. The authors suggest the use of surfactants and ionic liquids that promote MMT exfoliation to allow a higher specific area for silver ions adsorption. The article concludes with possible strategies to prolong the antibacterial activity of silver species in the MMT nano-clays. In keeping with very current concerns regarding the safety of drinking water, Changseok Han et al., from the USEPA and a US high-school, present an excellent update on nano-particle surface coatings that contain TiO2 photocatalysts. An article that describes the critically important properties of oxide, hard nitride and oxy-nitride coatings for the automotive sector is the focus of Sundararajan et al. This article extends predictions made about Plasma and Plasma like processes that were predicted as being significant to materials engineering for the next century [3]. Authors, Igor Filiminov and Alex Poletaev review a few combustion microkinetic models for obtaining various scales of microstructure. Last but not least, we would like to thank all authors and reviewers who graciously contributed their precious time and efforts to ensure high quality of the articles. The professional help from the editorial team of Elsevier, especially Ms. Patricia Hudson (Patries) and Justyna Kasprzycka, is gratefully acknowledged; without their help, the timely completion of this section would not have been possible.
References 1.
Kyu T: Curr Opin Chem Eng2013, 2:60 http://dx.doi.org/10.1016/ j.coche.2012.11.003.
2.
Kyu T, Sekhar JA: Curr Opin Chem Eng2014, 3:99 http:// dx.doi.org/10.1016/j.coche.2013.12.005.
3.
Sekhar JA: Curr Opin Chem Eng2015, 7:vii http://dx.doi.org/ 10.1016/j.coche.2014.12.002.
www.sciencedirect.com
Please cite this article in press as: Kyu T, Sekhar JA: Editorial overview: Materials engineering: Coatings and interfaces, Curr Opin Chem Eng (2016), http://dx.doi.org/10.1016/j.coche.2016.02.001