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A convenient UV-curable coatings assisted surface functionalization strategy is presented to convert commodity Poly(propylene) (PP) films into diverse functional materials. To ensure a covalent integration between PP surface and functional UV-curable coatings, 3-(trimethoxysilyl) propyl acrylate (TMSPA) was functionalized on the surface of oxidized PP film. Two distinct UV-curable coatings differing primarily in the chemical nature of monomers were separately tethered on the surface of TMSPA functionalized PP films. The monomers applied in this study include 1H, 1H,2H,2H-heptadecafluorodecyl acrylate (HFDA) and 2-isocyanatoethyl methacrylate (ICEMA). The use of HFDA as monomer resulted in PP film with fluorinated surface chemical nature, which would be attractive for applications desiring low surface energy, low dielectric constant, low flammability, low refractive index, and superior chemical resistance. Employing ICEMA monomer as part of UV-curable mixture resulted in PP film offering a high density of surface isocyanate groups (-NCO) that could be conveniently conjugated to a variety of amines to give a range of functional surfaces. For proof of concept, the -NCO groups on the surface of PP film were conjugated with amine terminated polyethylene glycol to give PP film that exhibited antifouling nature. In a separate experiment, the surface -NCO groups were conjugated to 2-aminoethanesufonic acid (AESA) to fabricate an anionic PP surface capable of effectively interacting with cationic species. The conjugation of surface -NCO groups with L-lysine imparted pH responsive wettability switching behaviour to the surface of PP film. Finally, poly(ethylene imine) (PEI) was conjugated to surface -NCO groups and the resulting surface PEI moieties were used as reducing and stabilizing agent to synthesize catalytically active gold nanoparticles (AuNPs) confined to the surface of PP film. All the surface functionalization's were fully corroborated by attenuated total reflecta, HFSP grant [RGY0074/2016]; HEC grant [20-1740/RD/10/3368, 20-1799/RD/10-5302, 5922, TDF-033]; LUMS; Max-Planck-Gesellschaft (MPG)Max Planck Society, B.Y. acknowledges support from HFSP (RGY0074/2016), HEC for NRPU (Project No. 20-1740/R;D/10/3368, 20-1799/R;D/10-5302 and 5922), TDF-033) grants, and LUMS for start-up fund and FIF grant. H.D. gratefully acknowledges Max-Planck-Gesellschaft (MPG) for the financial support of the MPIP-TOBB ETU Partner Group Program (Soft Matter in Nanoconfinement). Murtaza Saleem and Syed Zajif Hussain are acknowledging for their support with SEM imaging.

A convenient UV-curable coatings assisted surface functionalization strategy is presented to convert commodity Poly(propylene) (PP) films into diverse functional materials. To ensure a covalent integration between PP surface and functional UV-curable coatings, 3-(trimethoxysilyl) propyl acrylate (TMSPA) was functionalized on the surface of oxidized PP film. Two distinct UV-curable coatings differing primarily in the chemical nature of monomers were separately tethered on the surface of TMSPA functionalized PP films. The monomers applied in this study include 1H, 1H,2H,2H-heptadecafluorodecyl acrylate (HFDA) and 2-isocyanatoethyl methacrylate (ICEMA). The use of HFDA as monomer resulted in PP film with fluorinated surface chemical nature, which would be attractive for applications desiring low surface energy, low dielectric constant, low flammability, low refractive index, and superior chemical resistance. Employing ICEMA monomer as part of UV-curable mixture resulted in PP film offering a high density of surface isocyanate groups (-NCO) that could be conveniently conjugated to a variety of amines to give a range of functional surfaces. For proof of concept, the -NCO groups on the surface of PP film were conjugated with amine terminated polyethylene glycol to give PP film that exhibited antifouling nature. In a separate experiment, the surface -NCO groups were conjugated to 2-aminoethanesufonic acid (AESA) to fabricate an anionic PP surface capable of effectively interacting with cationic species. The conjugation of surface -NCO groups with L-lysine imparted pH responsive wettability switching behaviour to the surface of PP film. Finally, poly(ethylene imine) (PEI) was conjugated to surface -NCO groups and the resulting surface PEI moieties were used as reducing and stabilizing agent to synthesize catalytically active gold nanoparticles (AuNPs) confined to the surface of PP film. All the surface functionalization's were fully corroborated by attenuated total reflecta, HFSP grant [RGY0074/2016]; HEC grant [20-1740/RD/10/3368, 20-1799/RD/10-5302, 5922, TDF-033]; LUMS; Max-Planck-Gesellschaft (MPG)Max Planck Society, B.Y. acknowledges support from HFSP (RGY0074/2016), HEC for NRPU (Project No. 20-1740/R;D/10/3368, 20-1799/R;D/10-5302 and 5922), TDF-033) grants, and LUMS for start-up fund and FIF grant. H.D. gratefully acknowledges Max-Planck-Gesellschaft (MPG) for the financial support of the MPIP-TOBB ETU Partner Group Program (Soft Matter in Nanoconfinement). Murtaza Saleem and Syed Zajif Hussain are acknowledging for their support with SEM imaging.

The development of antimicrobial surfaces has become a high priority in recent times. There are two ongoing worldwide health crises: the COVID-19 pandemic provoked by the SARS-CoV-2 virus and the antibiotic-resistant diseases provoked by bacteria resistant to antibiotic-based treatments. The need for antimicrobial surfaces against bacteria and virus is a common factor to both crises. Most extended strategies to prevent bacterial associated infections rely on chemical based-approaches based on surface coatings or biocide encapsulated agents that release chemical agents. A critical limitation of these chemistry-based strategies is their limited effectiveness in time while grows the concerns about the long-term toxicity on human beings and environment pollution. An alternative strategy to prevent bacterial attachment consists in the introduction of physical modification to the surface. Pursuing this chemistry-independent strategy, we present a fabrication process of surface topographies [one-level (micro, nano) and hierarchical (micro+nano) structures] in polypropylene (PP) substrates and discuss how wettability, topography and patterns size influence on its antibacterial properties. Using nanoimprint lithography as patterning technique, we report as best results 82 and 86% reduction in the bacterial attachment of E. coli and S. aureus for hierarchically patterned samples compared to unpatterned reference surfaces. Furthermore, we benchmark the mechanical properties of the patterned PP surfaces against commercially available antimicrobial films and provide evidence for the patterned PP films to be suitable candidates for use as antibacterial functional surfaces in a hospital environment.

In this paper, a state-of-the-art review on cutting tool technology in machining of Ni-based superalloys is presented to better understand the current status and to identify future directions of research and development of cutting tool technologies. First, past review articles related to the machining of Ni-based superalloys are summarized. Then machinability of superalloys is introduced, together with the reported methods used in cutting tool design. The current researches on cutting tools in the machining of superalloys are presented in different categories in terms of tool materials, i.e., carbide, ceramics, and Polycrystalline cubic boron nitride (PCBN). Moreover, a set of research issues are identified and highlighted to improve the machining of superalloys. Finally, discussions on the future development are presented, in the areas of new materials/geometries, functional surfaces on the cutting tool, and data-driven comprehensive optimization., QC 20201229

Bacterial biofilm formation on medical devices is a threat to healthcare systems worldwide as bacteria within a biofilm are more resistant to standard antimicrobial therapies. Herein, we introduce a nitroxide-based antibiofilm coating strategy, which is specifically designed to prevent biofilm formation of Gram-negative pathogens such as Pseudomonas aeruginosa. Nitroxide-decorated hydroxyapatite surfaces were readily prepared in an aqueous dip-coating procedure using a nitroxide-functionalized catecholamine as a polymerizable coating agent. Additional spatial control over the polymer surface deposition on titanium was gained by applying a photolithographic coating setup. All nitroxide-coated surfaces exhibited excellent antibiofilm properties toward PA14 surface colonization as biofilm formation was completely suppressed. Importantly, the surrounding adhesive polymer matrix did not interfere with the nitroxide-characteristic antibiofilm properties. The herein introduced platform technology represents a bioinspired and versatile coating approach, offering a safe and prophylactic avenue to combat biofilm contamination on a variety of surfaces.

This work presents an Additive Manufacturing (AM) based method for production of components with micro-structured surfaces. Vat photopolymerization was used for the experiments by an AM custom-build machine at the Technical University of Denmark (DTU). Components with micro holes were printed in different sizes and the uniformity of them analyzed. Subsequently, in order to assess the functionality of the surface, the water droplet contact angle was measured to evaluate the wettability of the different components with micro holes. It was found that it was possible to fabricate the components with micro holes using precision AM process. The printed substrate exhibited hydrophobicity as a hydrophilic material (intrinsic contact angle of 65°). A hydrophobic surface was achieved with the printed features exhibiting a maximum contact angle of 113°. Additionally, the volume of fluid (VOF) method was employed to predict the surface contact angle. The predicted results were validated by comparison against the experiments. The average value from experiments was predicted by the model. However, it was noted that the cross-sectional height profile of the structures and the surface roughness of the printed samples, were not precisely replicated as designed, which slightly affects the prediction results, though, similar prediction trend was observed.

We show that an azopolymer can be used to create a supramolecular architecture in a parallel process with patterned surface properties. By illuminating with an interference pattern, we created adhesion and charge patterns that reflect the molecular ordering. We studied the recording process in two limit situations. When birefringence dominates over mass transport, an adhesion pattern was recorded even in absence of a surface relief grating (SRG). When mass transport dominates, we measured a higher frequency adhesion and relief patterns on top of the SRG. We measured an increased negative charge in the regions where molecules are expected to be parallel aligned in trans conformational state.

The functional properties of micro-structured surfaces have gained increasing interest thanks to many applications such as wetting, adhesion, thermal and/or electrical conductivity. In this study, directional optical properties, i.e. contrast between two regions of a surface, were achieved with an anisotropic microstructure composed of a close array of ridges. The anisotropic surface, designed as a combination of ridges, has been milled on a steel bar and replicated through hot embossing of Acrylonitrile butadiene styrene (ABS) and through replica technology using silicone rubber. The directional reflectance of the surface for a range of design-specific view-illumination configurations was determined using a method that involves a Hirox RH-2000 digital microscope, used as a gonioreflectometer. This method allows the empirical determination of the optimum surface microstructure for maximizing contrast between two horizontally orthogonal views. The results show that even if the uncertainty related to the instrumentation is up to 20% in some cases, this procedure is suitable for the characterization of the surface of both metal and plastic counterpart.

Functional surfaces have proven their potential to solve many engineering problems, attracting great interest among the scientific community. Bio-inspired multi-hierarchical micro-structures grant the surfaces with new properties, such as hydrophobicity, adhesion, unique optical properties and so on. The geometry and fabrication of these surfaces are still under research. In this study, the feasibility of using direct fabrication of microscale features by Additive Manufacturing (AM) processes was investigated. The investigation was carried out using a specifically designed vat photopolymerization AM machine-tool suitable for precision manufacturing at the micro dimensional scale which has previously been developed, built and validated at the Technical University of Denmark. It was shown that it was possible to replicate a simplified surface inspired by the Tokay gecko, the geometry was previously designed and replicated by a complex multi-step micromanufacturing method extracted from the literature and used as benchmark. Ultimately, the smallest printed features were analyzed by conducting a sensitivity analysis to obtain the righteous parameters in terms of layer thickness and exposure time. Moreover, two more intricate designs were fabricated with the same parameters to assess the surfaces functionality by its wettability. The surface with increased density and decreased feature size showed a water contact angle (CA) of 124°±0.10°, agreeing with the Cassie-Baxter model. These results indicate the possibility of using precision AM for a rapid, easy and reliable fabrication method for functional surfaces.

This paper discusses a new micro milling strategy for manufacturing optical functionality on steel. The micro-structures, a combination of arrays of micro-ridges, has been developed to achieve the function. The function is to maximize the contrast of the reflected light from orthogonally patterned features. The burr formation and insufficient material removal, influenced by the tool wear and the machine accuracy, were the main challenges in this process. The cutting strategy was investigated in order to reduce the burr formation during the process. By the new strategy, the ridge machining order was reversed. The evaluation of the feature geometries proved that new strategy could improve the feature quality. The ultimate goal was to improve the surface functionality.

Within the scope of the Collaborative Research Centre (CRC) 1153 novel process chains for the production of hybrid solid components by Tailored Forming are developed at the Leibniz Universität Hannover. The combination of e. g. aluminium with steel allows to produce hybrid compounds with wear-resistant functional surfaces and reduced weight. In these process chains, joining takes place as the first step to produce hybrid semi-finished products by friction welding, cladding, ultrasonic assisted laser welding or co-extrusion, which are subsequently subjected to various forming processes such as forging or impact extrusion. The coaxially joined hybrid semifinished components investigated in this work were produced by means of the lateral angular co-extrusion (LACE) process using the aluminium alloy EN AW-6082 and the case-hardening steel 20MnCr5. These semi-finished products shall be suited to produce hybrid bearing bushings by die forging in a subsequent process step. Initial investigations for the determination of the process parameters and the appropriate tool geometry were made using a steel rod. In future investigations, a steel tube will replace the steel rod in order to produce hybrid semi-finished products, which can be fully integrated into the process chain. The mechanical properties of the profile were determined at different positions along its length. For this purpose, the quality of the joining zone between aluminium and steel as a function of the profile position was examined by means of push-out tests. Moreover, the mechanical properties of the aluminium component's longitudinal weld seam were determined by micro-tensile-tests. © 2017 Trans Tech Publications, Switzerland.

In this work we demonstrate that Reverse Nanoimprint Lithography is a feasible and flexible lithography technique applicable to the transfer of micro and nano polymer structures with no residual layer over areas of cm2 areas on silicon, metal and non-planar substrates. We used a flexible polydimethylsiloxane stamp with hydrophobic features. We present residual layer-free patterns imprinted using a commercial poly(methylmethacrylate) thermoplastic polymer over silicon, nickel and pre-patterned substrates. Our versatile patterning technology is adaptable to free form nano structuring and has coupling to adhesion technologies.

Article shows the calculation of the stress in a rotating disc and the possibility of using proprietary forms of instruments for speed grinding. It presents the results of speed and efficient cutting tools in machining these materials alloyed with chromium. In addition, it notes the results of the influence of technological conditions on the quality of surfaces, the residual stress in the workpiece, resulting from the machining speed and the influence of technological conditions on the wear of grinding wheels. Finally, some options for the use of finishing techniques in practice are mentioned.

Article shows the calculation of the stress in a rotating disc and the possibility of using proprietary forms of instruments for speed grinding. It presents the results of speed and efficient cutting tools in machining these materials alloyed with chromium. In addition, it notes the results of the influence of technological conditions on the quality of surfaces, the residual stress in the workpiece, resulting from the machining speed and the influence of technological conditions on the wear of grinding wheels. Finally, some options for the use of finishing techniques in practice are mentioned.

Proposed in this work is a method for real-time 3D human pose tracking using depth video with the ability to learn and utilize functional environmental features from the scene. Learning environmental features is done by pose classifications of the tracked trajectory for recovering pose-to-surface interaction points, resulting in surfaces represented by floating planes, either bounded or unbounded. In the tracking method surfaces can be utilized for inferring likely poses for interaction with the surfaces, as well as be utilized as hard physical constraints for reducing freedom of interpretation in the tracker.The method employed for tracking is a top-down approach, with the only significant learning criterion being a library of prefabricated body poses in this implementation inhabited by 15 variants distributed into three categories.The method used for inferring likely poses of interaction with the environment is created explicitly for use in this work, and includes a nearness measure along with a 1NN classification using the tracked state and the defined pose library.The method used for pose classifications for learning surfaces is a 1NN approach using the tracked state and the defined pose library to gather interaction points, to which an orthogonal least squares plane fitting method is applied.For evaluation of the method a dataset consisting of two sequences was created, with synchronized depth- and motion capture data, containing challenging poses. Additionally two other data sources were included, also having synchronized depth- and motion capture data.The results suggest an achievable benefit in tracking robustness from knowing the environment, as well as an achievable method for learning specific parts of this environment during tracking. However, not every type of environmental features could be feasibly detected and used.

Proposed in this work is a method for real-time 3D human pose tracking using depth video with the ability to learn and utilize functional environmental features from the scene. Learning environmental features is done by pose classifications of the tracked trajectory for recovering pose-to-surface interaction points, resulting in surfaces represented by floating planes, either bounded or unbounded. In the tracking method surfaces can be utilized for inferring likely poses for interaction with the surfaces, as well as be utilized as hard physical constraints for reducing freedom of interpretation in the tracker.The method employed for tracking is a top-down approach, with the only significant learning criterion being a library of prefabricated body poses in this implementation inhabited by 15 variants distributed into three categories.The method used for inferring likely poses of interaction with the environment is created explicitly for use in this work, and includes a nearness measure along with a 1NN classification using the tracked state and the defined pose library.The method used for pose classifications for learning surfaces is a 1NN approach using the tracked state and the defined pose library to gather interaction points, to which an orthogonal least squares plane fitting method is applied.For evaluation of the method a dataset consisting of two sequences was created, with synchronized depth- and motion capture data, containing challenging poses. Additionally two other data sources were included, also having synchronized depth- and motion capture data.The results suggest an achievable benefit in tracking robustness from knowing the environment, as well as an achievable method for learning specific parts of this environment during tracking. However, not every type of environmental features could be feasibly detected and used.

The employment of surface texturing for improved tribological contacts has spread over the years. The possibilities of designing and manufacturing textured surfaces with predetermined geometries have multiplied as well as the need of performing experimental laboratory tests before applying the surfaces in an industrial context. In this paper, a number of experimental tests were performed using a novel test rig, called axial sliding test, simulating the contact of surfaces under pure sliding conditions. The aim of the experiments is to evaluate the frictional behavior of a new typology of textured surfaces, the so-called multifunctional surfaces, characterized by a plateau area able to bear loads and a deterministic pattern of lubricant pockets. Six surface typologies, namely three multifunctional and three machined using classical processes, were chosen to slide against a mirror-polished counterpart. A number of experiments were carried out at different normal pressures employing for all specimens the same reciprocating movement and the same lubrication. The measured friction forces were plotted against the incremental normal pressure, and the friction coefficients were calculated. The results comparison showed clearly how employing multifunctional surfaces can reduce friction forces up to 50 % at high normal loads compared to regularly ground or turned surfaces. Friction coefficients approximately equal to 0.12 were found for classically machined surfaces, whereas the values were 0.06 for multifunctional ones. All the specimens were characterized before and after testing. Wear occurrence was not detected on the tested surfaces except for the mirror-polished one which underwent all the experiments.

Hydrophobic isoporous membranes were fabricated using the "breath figure" method from polystyrene stars synthesized via ATRP. The living polymer chain ends at the surface of the films were then used, without further modification, in a "grafting-from" approach to grow surface-linked polyglycidyl methacrylate chains under conditions that maintained the regular honeycomb structure. This versatile functional surface was then used as a platform to build a small library of surfaces using a variety of simple chemistries: (i) the acid hydrolysis of the epoxide to form bis-alcohol groups and (ii) utilizing the "click-like" epoxide-amine reaction to functionalize the surface with a model biomolecule-(biotinamido)pentylamine. The successful modifications were confirmed by a combination of spectroscopic and biological means. Changes in the growth characteristics of nonmotile Psychrobacter sp. strain, SW5, on the honeycomb films, provided further evidence confirming changes in the hydrophobicity of the surface upon grafting., QC 20101022

In this study we investigate the potential of femtosecond laser generated micrometer sized spike structures as functional surfaces for selective cell controlling. The spike dimensions as well as the average spike to spike distance can be easily tuned by varying the process parameters. Moreover, negative replications in soft materials such as silicone elastomer can be produced. This allows tailoring of wetting properties of the spike structures and their negative replicas representing a reduced surface contact area. Furthermore, we investigated material effects on cellular behavior. By comparing human fibroblasts and SH-SY5Y neuroblastoma cells we found that the influence of the material was cell specific. The cells not only changed their morphology, but also the cell growth was affected. Whereas, neuroblastoma cells proliferated at the same rate on the spike structures as on the control surfaces, the proliferation of fibroblasts was reduced by the spike structures. These effects can result from the cell specific adhesion patterns as shown in this work. These findings show a possibility to design defined surface microstructures, which could control cellular behavior in a cell specific manner.

In this study, surface modification of both organic and inorganic substrates (in terms of cellulose and silica nanoparticles, respectively) has been explored using surface-initiated atom transfer radical polymerisation (ATRP). The desire to modify bio-based materials to fit into new application areas and the need for bio-based materials with improved material properties is steadily increasing due to environmental concern. Superhydrophobic and self-cleaning cellulose surfaces were fabricated by combining ATRP with post-functionalisation. Glycidyl methacrylate was grafted from filter paper, and the epoxide groups were used as reactive handles to create a branched “graft-on-graft” architecture. Post-functionalisation of this architecture with perfluorinated chains or alkyl chains resulted in the formation of superhydrophobic surfaces. Grafting of N-isopropylacrylamide (NIPAAm) from filter paper yielded cellulose surfaces capable of switching the wettability, from hydrophilic to hydrophobic, in response to changes in temperature. The wettability of cellulose surfaces grafted with poly(4-vinylpyridine) (P4VP) could be adjusted from hydrophilic to hydrophobic by changing pH. Furthermore, cellulose surfaces responding to changes in both pH and temperature were obtained via grafting of block copolymers of PNIPAAm and P4VP. The use of inorganic nano-particles in composites has attracted considerable academic and industrial interest due to their excellent mechanical and thermal properties. Styrene was grafted from the surface of silica nanoparticles using ATRP. The resulting organic-inorganic hybrid materials did not aggregate to the same extent as the un-modified silica particles. The polystyrene-modified silica particles were used for the fabrication of honeycomb membranes. It was evident that the pore sizes and the number of porous layers could be tuned by varying the conditions used for film casting. To broaden the range of polymers available for film casting into honeyco, QC 20100901

In this study, surface modification of both organic and inorganic substrates (in terms of cellulose and silica nanoparticles, respectively) has been explored using surface-initiated atom transfer radical polymerisation (ATRP). The desire to modify bio-based materials to fit into new application areas and the need for bio-based materials with improved material properties is steadily increasing due to environmental concern. Superhydrophobic and self-cleaning cellulose surfaces were fabricated by combining ATRP with post-functionalisation. Glycidyl methacrylate was grafted from filter paper, and the epoxide groups were used as reactive handles to create a branched “graft-on-graft” architecture. Post-functionalisation of this architecture with perfluorinated chains or alkyl chains resulted in the formation of superhydrophobic surfaces. Grafting of N-isopropylacrylamide (NIPAAm) from filter paper yielded cellulose surfaces capable of switching the wettability, from hydrophilic to hydrophobic, in response to changes in temperature. The wettability of cellulose surfaces grafted with poly(4-vinylpyridine) (P4VP) could be adjusted from hydrophilic to hydrophobic by changing pH. Furthermore, cellulose surfaces responding to changes in both pH and temperature were obtained via grafting of block copolymers of PNIPAAm and P4VP. The use of inorganic nano-particles in composites has attracted considerable academic and industrial interest due to their excellent mechanical and thermal properties. Styrene was grafted from the surface of silica nanoparticles using ATRP. The resulting organic-inorganic hybrid materials did not aggregate to the same extent as the un-modified silica particles. The polystyrene-modified silica particles were used for the fabrication of honeycomb membranes. It was evident that the pore sizes and the number of porous layers could be tuned by varying the conditions used for film casting. To broaden the range of polymers available for film casting into honeyco, QC 20100901

In this study, surface modification of both organic and inorganic substrates (in terms of cellulose and silica nanoparticles, respectively) has been explored using surface-initiated atom transfer radical polymerisation (ATRP). The desire to modify bio-based materials to fit into new application areas and the need for bio-based materials with improved material properties is steadily increasing due to environmental concern. Superhydrophobic and self-cleaning cellulose surfaces were fabricated by combining ATRP with post-functionalisation. Glycidyl methacrylate was grafted from filter paper, and the epoxide groups were used as reactive handles to create a branched “graft-on-graft” architecture. Post-functionalisation of this architecture with perfluorinated chains or alkyl chains resulted in the formation of superhydrophobic surfaces. Grafting of N-isopropylacrylamide (NIPAAm) from filter paper yielded cellulose surfaces capable of switching the wettability, from hydrophilic to hydrophobic, in response to changes in temperature. The wettability of cellulose surfaces grafted with poly(4-vinylpyridine) (P4VP) could be adjusted from hydrophilic to hydrophobic by changing pH. Furthermore, cellulose surfaces responding to changes in both pH and temperature were obtained via grafting of block copolymers of PNIPAAm and P4VP. The use of inorganic nano-particles in composites has attracted considerable academic and industrial interest due to their excellent mechanical and thermal properties. Styrene was grafted from the surface of silica nanoparticles using ATRP. The resulting organic-inorganic hybrid materials did not aggregate to the same extent as the un-modified silica particles. The polystyrene-modified silica particles were used for the fabrication of honeycomb membranes. It was evident that the pore sizes and the number of porous layers could be tuned by varying the conditions used for film casting. To broaden the range of polymers available for film casting into honeyco, QC 20100901

In this study, surface modification of both organic and inorganic substrates (in terms of cellulose and silica nanoparticles, respectively) has been explored using surface-initiated atom transfer radical polymerisation (ATRP). The desire to modify bio-based materials to fit into new application areas and the need for bio-based materials with improved material properties is steadily increasing due to environmental concern. Superhydrophobic and self-cleaning cellulose surfaces were fabricated by combining ATRP with post-functionalisation. Glycidyl methacrylate was grafted from filter paper, and the epoxide groups were used as reactive handles to create a branched “graft-on-graft” architecture. Post-functionalisation of this architecture with perfluorinated chains or alkyl chains resulted in the formation of superhydrophobic surfaces. Grafting of N-isopropylacrylamide (NIPAAm) from filter paper yielded cellulose surfaces capable of switching the wettability, from hydrophilic to hydrophobic, in response to changes in temperature. The wettability of cellulose surfaces grafted with poly(4-vinylpyridine) (P4VP) could be adjusted from hydrophilic to hydrophobic by changing pH. Furthermore, cellulose surfaces responding to changes in both pH and temperature were obtained via grafting of block copolymers of PNIPAAm and P4VP. The use of inorganic nano-particles in composites has attracted considerable academic and industrial interest due to their excellent mechanical and thermal properties. Styrene was grafted from the surface of silica nanoparticles using ATRP. The resulting organic-inorganic hybrid materials did not aggregate to the same extent as the un-modified silica particles. The polystyrene-modified silica particles were used for the fabrication of honeycomb membranes. It was evident that the pore sizes and the number of porous layers could be tuned by varying the conditions used for film casting. To broaden the range of polymers available for film casting into honeyco, QC 20100901

The potential use of renewable, bio-based polymers in high-technological applications has attracted great interest due to increased environmental concern. Cellulose is the most abundant biopolymer resource in the world, and it has great potential to be modified to suit new application areas. The development of controlled polymerization techniques, such as atom transfer radical polymerization (ATRP), has made it possible to graft well-defined polymers from cellulose surfaces. In this study, graft-modification of cellulose substrates by ATRP was explored as a tool for tailoring surface properties and for the fabrication of functional cellulose surfaces. Various native and regenerated cellulose substrates were successfully graft-modified to investigate the effect of surface morphology on the grafting reactions. It was found that significantly denser polymer brushes were grafted from the native than from the regenerated cellulose substrates, most likely due to differences in surface area. A method for detaching the grafted polymer from the substrate was developed, based on the selective cleavage of silyl ether bonds with tetrabutylammonium fluoride. The results from the performed kinetic study suggest that the surface-initiated polymerization of methyl methacrylate from cellulose proceeds faster than the concurrent solution polymerization at low monomer conversions, but slows down to match the kinetics of the solution polymerization at higher conversions. Superhydrophobic and self-cleaning bio-fiber surfaces were obtained by grafting of glycidyl methacrylate using a branched graft-on-graft architecture, followed by post-functionalization to obtain fluorinated polymer brushes. AFM analysis showed that the surface had a micro-nano-binary structure. It was also found that superhydrophobic surfaces could be achieved by post-functionalization with an alkyl chain, with no use of fluorine. Thermo-responsive cellulose surfaces have been prepared by graft-modification with the s, QC 20100804

The potential use of renewable, bio-based polymers in high-technological applications has attracted great interest due to increased environmental concern. Cellulose is the most abundant biopolymer resource in the world, and it has great potential to be modified to suit new application areas. The development of controlled polymerization techniques, such as atom transfer radical polymerization (ATRP), has made it possible to graft well-defined polymers from cellulose surfaces. In this study, graft-modification of cellulose substrates by ATRP was explored as a tool for tailoring surface properties and for the fabrication of functional cellulose surfaces. Various native and regenerated cellulose substrates were successfully graft-modified to investigate the effect of surface morphology on the grafting reactions. It was found that significantly denser polymer brushes were grafted from the native than from the regenerated cellulose substrates, most likely due to differences in surface area. A method for detaching the grafted polymer from the substrate was developed, based on the selective cleavage of silyl ether bonds with tetrabutylammonium fluoride. The results from the performed kinetic study suggest that the surface-initiated polymerization of methyl methacrylate from cellulose proceeds faster than the concurrent solution polymerization at low monomer conversions, but slows down to match the kinetics of the solution polymerization at higher conversions. Superhydrophobic and self-cleaning bio-fiber surfaces were obtained by grafting of glycidyl methacrylate using a branched graft-on-graft architecture, followed by post-functionalization to obtain fluorinated polymer brushes. AFM analysis showed that the surface had a micro-nano-binary structure. It was also found that superhydrophobic surfaces could be achieved by post-functionalization with an alkyl chain, with no use of fluorine. Thermo-responsive cellulose surfaces have been prepared by graft-modification with the s, QC 20100804

The potential use of renewable, bio-based polymers in high-technological applications has attracted great interest due to increased environmental concern. Cellulose is the most abundant biopolymer resource in the world, and it has great potential to be modified to suit new application areas. The development of controlled polymerization techniques, such as atom transfer radical polymerization (ATRP), has made it possible to graft well-defined polymers from cellulose surfaces. In this study, graft-modification of cellulose substrates by ATRP was explored as a tool for tailoring surface properties and for the fabrication of functional cellulose surfaces. Various native and regenerated cellulose substrates were successfully graft-modified to investigate the effect of surface morphology on the grafting reactions. It was found that significantly denser polymer brushes were grafted from the native than from the regenerated cellulose substrates, most likely due to differences in surface area. A method for detaching the grafted polymer from the substrate was developed, based on the selective cleavage of silyl ether bonds with tetrabutylammonium fluoride. The results from the performed kinetic study suggest that the surface-initiated polymerization of methyl methacrylate from cellulose proceeds faster than the concurrent solution polymerization at low monomer conversions, but slows down to match the kinetics of the solution polymerization at higher conversions. Superhydrophobic and self-cleaning bio-fiber surfaces were obtained by grafting of glycidyl methacrylate using a branched graft-on-graft architecture, followed by post-functionalization to obtain fluorinated polymer brushes. AFM analysis showed that the surface had a micro-nano-binary structure. It was also found that superhydrophobic surfaces could be achieved by post-functionalization with an alkyl chain, with no use of fluorine. Thermo-responsive cellulose surfaces have been prepared by graft-modification with the s, QC 20100804

The potential use of renewable, bio-based polymers in high-technological applications has attracted great interest due to increased environmental concern. Cellulose is the most abundant biopolymer resource in the world, and it has great potential to be modified to suit new application areas. The development of controlled polymerization techniques, such as atom transfer radical polymerization (ATRP), has made it possible to graft well-defined polymers from cellulose surfaces. In this study, graft-modification of cellulose substrates by ATRP was explored as a tool for tailoring surface properties and for the fabrication of functional cellulose surfaces. Various native and regenerated cellulose substrates were successfully graft-modified to investigate the effect of surface morphology on the grafting reactions. It was found that significantly denser polymer brushes were grafted from the native than from the regenerated cellulose substrates, most likely due to differences in surface area. A method for detaching the grafted polymer from the substrate was developed, based on the selective cleavage of silyl ether bonds with tetrabutylammonium fluoride. The results from the performed kinetic study suggest that the surface-initiated polymerization of methyl methacrylate from cellulose proceeds faster than the concurrent solution polymerization at low monomer conversions, but slows down to match the kinetics of the solution polymerization at higher conversions. Superhydrophobic and self-cleaning bio-fiber surfaces were obtained by grafting of glycidyl methacrylate using a branched graft-on-graft architecture, followed by post-functionalization to obtain fluorinated polymer brushes. AFM analysis showed that the surface had a micro-nano-binary structure. It was also found that superhydrophobic surfaces could be achieved by post-functionalization with an alkyl chain, with no use of fluorine. Thermo-responsive cellulose surfaces have been prepared by graft-modification with the s, QC 20100804

Tato bakalářská práce se zabývá bezkontaktním hodnocením textury povrchu. Cílem práce je rešeršní popis problematiky parametrů textury povrchu a bezkontaktních metod jejich měření. Pozornost je převážně věnována předpisům vhodných parametrů pro funkční plochy dle jejich aplikace. V závěru této práce jsou zpracována obecná doporučení pro výběr vhodných parametrů textury povrchu k funkčním plochám, která jsou následně aplikována na konkrétní příklady. Bylo zjištěno, že k důkladnému popisu funkčních ploch je zapotřebí značného množství parametrů a nákladných experimentálních výzkumů, a proto dosavadní hodnocení drsnosti povrchu pomocí parametru Ra případně Sa je příhodné., This bachelor’s thesis focuses on non-contact methods for surface texture evaluation. The aim of the thesis is to describe a set of surface texture parameters and non-contact methods of their measurement. It‘s main focus is the prescription of suitable parameters for functional surfaces according to their application. The conclusion of the thesis consists of general recommendations for selection of suitable surface texture parameters for functional surfaces, which are applied to specific surfaces occurring in practice. It has been found that a considerable number of parameters and costly experimental research is required for a thorough description of the functional surfaces, and therefore the current evaluation of the surface roughness by means of the Ra and Sa parameters is convenient.

Tato bakalářská práce se zabývá bezkontaktním hodnocením textury povrchu. Cílem práce je rešeršní popis problematiky parametrů textury povrchu a bezkontaktních metod jejich měření. Pozornost je převážně věnována předpisům vhodných parametrů pro funkční plochy dle jejich aplikace. V závěru této práce jsou zpracována obecná doporučení pro výběr vhodných parametrů textury povrchu k funkčním plochám, která jsou následně aplikována na konkrétní příklady. Bylo zjištěno, že k důkladnému popisu funkčních ploch je zapotřebí značného množství parametrů a nákladných experimentálních výzkumů, a proto dosavadní hodnocení drsnosti povrchu pomocí parametru Ra případně Sa je příhodné., This bachelor’s thesis focuses on non-contact methods for surface texture evaluation. The aim of the thesis is to describe a set of surface texture parameters and non-contact methods of their measurement. It‘s main focus is the prescription of suitable parameters for functional surfaces according to their application. The conclusion of the thesis consists of general recommendations for selection of suitable surface texture parameters for functional surfaces, which are applied to specific surfaces occurring in practice. It has been found that a considerable number of parameters and costly experimental research is required for a thorough description of the functional surfaces, and therefore the current evaluation of the surface roughness by means of the Ra and Sa parameters is convenient.

Tato bakalářská práce se zabývá bezkontaktním hodnocením textury povrchu. Cílem práce je rešeršní popis problematiky parametrů textury povrchu a bezkontaktních metod jejich měření. Pozornost je převážně věnována předpisům vhodných parametrů pro funkční plochy dle jejich aplikace. V závěru této práce jsou zpracována obecná doporučení pro výběr vhodných parametrů textury povrchu k funkčním plochám, která jsou následně aplikována na konkrétní příklady. Bylo zjištěno, že k důkladnému popisu funkčních ploch je zapotřebí značného množství parametrů a nákladných experimentálních výzkumů, a proto dosavadní hodnocení drsnosti povrchu pomocí parametru Ra případně Sa je příhodné., This bachelor’s thesis focuses on non-contact methods for surface texture evaluation. The aim of the thesis is to describe a set of surface texture parameters and non-contact methods of their measurement. It‘s main focus is the prescription of suitable parameters for functional surfaces according to their application. The conclusion of the thesis consists of general recommendations for selection of suitable surface texture parameters for functional surfaces, which are applied to specific surfaces occurring in practice. It has been found that a considerable number of parameters and costly experimental research is required for a thorough description of the functional surfaces, and therefore the current evaluation of the surface roughness by means of the Ra and Sa parameters is convenient.

Tato bakalářská práce se zabývá bezkontaktním hodnocením textury povrchu. Cílem práce je rešeršní popis problematiky parametrů textury povrchu a bezkontaktních metod jejich měření. Pozornost je převážně věnována předpisům vhodných parametrů pro funkční plochy dle jejich aplikace. V závěru této práce jsou zpracována obecná doporučení pro výběr vhodných parametrů textury povrchu k funkčním plochám, která jsou následně aplikována na konkrétní příklady. Bylo zjištěno, že k důkladnému popisu funkčních ploch je zapotřebí značného množství parametrů a nákladných experimentálních výzkumů, a proto dosavadní hodnocení drsnosti povrchu pomocí parametru Ra případně Sa je příhodné., This bachelor’s thesis focuses on non-contact methods for surface texture evaluation. The aim of the thesis is to describe a set of surface texture parameters and non-contact methods of their measurement. It‘s main focus is the prescription of suitable parameters for functional surfaces according to their application. The conclusion of the thesis consists of general recommendations for selection of suitable surface texture parameters for functional surfaces, which are applied to specific surfaces occurring in practice. It has been found that a considerable number of parameters and costly experimental research is required for a thorough description of the functional surfaces, and therefore the current evaluation of the surface roughness by means of the Ra and Sa parameters is convenient.

Tato bakalářská práce se zabývá bezkontaktním hodnocením textury povrchu. Cílem práce je rešeršní popis problematiky parametrů textury povrchu a bezkontaktních metod jejich měření. Pozornost je převážně věnována předpisům vhodných parametrů pro funkční plochy dle jejich aplikace. V závěru této práce jsou zpracována obecná doporučení pro výběr vhodných parametrů textury povrchu k funkčním plochám, která jsou následně aplikována na konkrétní příklady. Bylo zjištěno, že k důkladnému popisu funkčních ploch je zapotřebí značného množství parametrů a nákladných experimentálních výzkumů, a proto dosavadní hodnocení drsnosti povrchu pomocí parametru Ra případně Sa je příhodné., This bachelor’s thesis focuses on non-contact methods for surface texture evaluation. The aim of the thesis is to describe a set of surface texture parameters and non-contact methods of their measurement. It‘s main focus is the prescription of suitable parameters for functional surfaces according to their application. The conclusion of the thesis consists of general recommendations for selection of suitable surface texture parameters for functional surfaces, which are applied to specific surfaces occurring in practice. It has been found that a considerable number of parameters and costly experimental research is required for a thorough description of the functional surfaces, and therefore the current evaluation of the surface roughness by means of the Ra and Sa parameters is convenient.