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The synthesis of adsorbents that meet the need for large‐scale production at relatively low cost that are capable of removing anionic and cationic toxic dyes from aqueous solutions, with high sorption capacity and reusability, is urgently needed from an environmental and industrial viewpoint. In this context the identification of hydrogels that remove dyes efficiently under ambient conditions and at near‐neutral pH, without the necessity pre‐treatment is an imperative. In this study we report the preparation of two hydrogels using the redox polymerization of acrylamide, hydroxyethyl methacrylate (HEMA) and N‐isoporpylacrylamide, H1 and acrylamide, HEMA, N‐isoporpylacrylamide and perylene‐5‐ylpent‐3‐yne‐2‐methylprop‐2‐enoate‐co‐2‐methyl‐2‐(prop‐2‐enoylamino) propane‐1‐sulfonic acid (PePnUMA‐Co‐AMPS), H2. These hydrogels proved to be effective for the removal of methylene blue (MB), fuchsin acid (FA) and congo red (CR) from aqueous solution at near‐neutral pH where their adsorption behaviour was in keeping with the Langmuir model having qmax values of 769.2 mg g−1 (MB), 1666.7 mg g−1 (FA) and 2358.2 mg g−1 (CR) respectively. Adsorption of MB and FA by these hydrogels follows pseudo‐first‐order kinetic, whilst the adsorption of CR follows pseudo‐second‐order kinetics. Detailed hermodynamic analysis indicated that the dye–adsorbent interaction as primarily one of physisorption in nature. Finally, desorption studies carried out in 1.0 M NaClO4 indicated that these adsorbents could be recycled at least four times using a variety of dyes while maintaining their mechanical properties.

The new title two-dimensional hetero-tetra nuclear Cu3–Na coordination polymer {[NaCu3Cl(cpiap)2(H2O)3]n·6nH2O} (1) consists of crystallographically two-independent copper(II) centers, each bridged by a sodium cation through carboxylate-oxygen of the deprotonated H3cpiap ligand (H3cpiap = 2-(carboxyphenyl)iminoaceticpropanoic acid) to CuII (2) and CuII (2−) cations, and through water molecules to CuII (1) cation. CuII (2) and CuII (1) cations are bridged by carboxylate-oxygen atoms of the ligand in a syn-anti mode which, alternate regularly within the chain being bridged by a tetra coordinated sodium cation. Each CuII (2) and CuII (2−) cation in (1) is in an octahedral environment formed by four carboxylate-oxygens from two cpiap3− ligands, one nitrogen atom and a bridging chloride atom. CuII (1) cation is in a square pyramidal environment formed by three water molecules and two carboxylate-oxygens from two cpiap3− ligands. The ligand acts simultaneously as monodentate and tridentate toward CuII (1) and CuII (2) cations respectively. The lattice water molecules involved in O H···O hydrogen bonding are situated in the void spaces between layers. The zigzag chains, which run along the b-axes further construct three-dimensional metal-organic framework via hydrogen bonding and weak face-to-face π-π interactions. Weak C H···O interactions are also present.

In this study, the antibacterial activity of tannic acid/amphiphilic cationic polymer (poly{2-[(methacryloyloxy)ethyl]trimethyl-ammonium chloride}, PMADQUAT) and tannic acid mixtures was examined on the strains of Gram-positive (S. aureus) and Gram-negative (E. coli CI2, E. coli K12, Klebsiella pneumonia and P. aeruginosa) bacteria. Tannic acid exhibited the antibacterial activity against all the studied bacterial strains. The ester linkage between glucose and gallic acid is vital for the antimicrobial activity of tannic acid. Tannic acid inhibited the growth of S. aureus and E. coli K12 (1 wt%) and reduced the growth of P. aeruginosa to 23%. Mixing cationic polymers having different structures (statistical copolymer, homopolymer and diblock polymer) with tannic acid lead to an increase in antibacterial activity of tannic acid and the stability and clarity of mixtures was higher than that of a pure tannic acid solution. Tannic acid/diblock polymer and tannic acid/homopolymer mixtures (0.1 wt%) were excellent for inhibiting the growth of planktonic E. coli K12 bacteria, and a low concentration (0.0001 wt%) of tannic acid/diblock polymer reduced its growth to 19%. By contrast, the tannic acid/statistical polymer mixture (0.0001 wt%) was excellent for inhibiting the growth of Gram-positive S. aureus bacteria.

Asphaltene deposition in petroleum refineries is known to be problematic as it reduces efficiencyand may lead to structural failure or production downtime. Though several successful approacheshave been utilized to limit deposition through the addition of dispersants and inhibitors topetroleum, these methods require constant intervention and are often expensive. In this study, wedemonstrate an innovative technique to engineer the surface chemistry of pipeline alloy steels toinhibit asphaltene deposition. Pack aluminization, a standard industrial-scale chemical vapordeposition process, is employed at a low temperature of 600 oC to aluminize API 5L X65 highstrength pipe steel substrates. The results showed deposit free steel surfaces after high-pressureand high-temperature fouling experiments. The improvement is attributed to the formation of analuminide intermetallic phase of Fe2Al5, which changes the native oxide chemistry to favoralumina over hematite. The continuous passivating oxide scale, acting as a protective barrier, mitigates asphaltene deposition and sulfidic corrosion. Since this process is based on alloying thesurface of the steel and is not a coating, it is not prone to delamination, and it can be reformedwhen damaged within the aluminized region. The combination of low-cost processing andimproved anti-fouling characteristics makes surface chemistry modification of steel a promisingpreventative approach against asphaltene deposition.

Current methods for the decontamination of radioactively contaminated surfaces in nuclear facilities typically rely on the use of liquid agents to remove radionuclides. This generates large volumes of highly hazardous liquid waste which must then be treated in costly processes which often require purpose built plant. For the first time we report a nitric acid loaded polymer hydrogel based approach which gives a high decontamination factor for the removal of 137Cs and 90Sr on 304 L grade stainless steel surfaces. The generation of minimal liquid waste and no lateral spread or increased penetration of radionuclides helps mitigate many of the intrinsic hazards of liquid based decontamination methods. Once dried these gels are able to retain the contaminants for treatment as solid waste resulting in a concentrated, less mobile waste form presenting significantly reduced hazards and treatment constraints.

In this work we demonstrate, for the first time, the use of polylactic acid (PLA) as a biodegradable host matrix for the construction of the active emissive layer of organic light‐emitting diode (OLED) devices for potential use in bioelectronics. In this preliminary study, we report a robust synthesis of two fluorescent PLA derivatives, pyrene‐PLA (AH10 ) and perylene‐PLA (AH11 ). These materials were prepared by the ring opening polymerisation of l ‐lactide with hydroxyalkyl‐pyrene and hydroxyalkyl‐perylene derivatives using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene as catalyst. OLEDs were fabricated from these materials using a simple device architecture involving a solution‐processed single‐emitting layer in the configuration ITO/PEDOT:PSS/PVK:OXD‐7 (35%):AH10 or AH11 (20%)/TPBi/LiF/Al (ITO, indium tin oxide; PEDOT:PSS, poly(3,4‐ethylenedioxythiophene) doped with poly(styrenesulfonic acid); PVK, poly(vinylcarbazole); OXD‐7, (1,3‐phenylene)‐bis‐[5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole]; TPBi, 2,2′,2″‐(1,3,5‐benzenetriyl)tris(1‐phenyl‐1H‐benzimidazole)). The turn‐on voltage for the perylene OLED at 10 cd m–2 was around 6 V with a maximum brightness of 1200 cd m–2 at 13 V. The corresponding external quantum efficiency and device current efficiency were 1.5% and 2.8 cd A–1 respectively. In summary, this study provides proof of principle that OLEDs can be constructed from PLA, a readily available and renewable bio‐source.

The effect of anisole/decane binary solvent mixture and the subsequent addition of low wt% aPS on 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene) thin film morphology is investigated by optical microscopy, AFM and UV–Vis measurements. We show that, over the composition range anisole/decane of 96/4 to 85/15 wt%, the solution maintains an azeotropic composition with the boiling point of the binary mixture remaining constant at 152 °C, and the solvent composition remaining constant during evaporation and drying. It was found that addition of up to 20 wt% decane has little impact on micro-scale crystal morphology but has a significant influence on the growth mode and terrace roughness. The formation of large crystals is explained in terms of the change in solvent, increase in decane content, weakening the solute–solvent interactions and promoting efficient nucleation of the favoured H-aggregates of TIPS-pentacene. The effect of the TIPS-pentacene—aPS ratio up to 20 wt% for drop-cast thin film was similarly investigated. It is found that addition of aPS has a significant effect on both macroscopic crystal properties such as surface coverage, unity of orientation and long range order. It also changes the surface morphology and layer ordering on the nano-scale.

The use of copolymeric micelles of copoly(oxyalkylene)s for dissolution of poorly soluble bioactive compounds has been studied due to their efficiency in the blood dilution process and biocompatibility. In this study we investigated the use of micellar system of copolymers F127, EO65SO9EO65 (EO = ethylene oxide/SO = styrene oxide) and the binary mixtures of these copolymers for the solubilization of lapachol. Solubility was estimated by UV–Vis. The samples, with and without drug, were characterized by X-ray, DSC, particle size and zeta potential. The antioxidant activity, the cytotoxicity and the release assay for the system SO970(blend of EO65SO9EO65/F127 in the proportions 70/30) were also investigated. The SO970LA system presented the best solubilization capacity (Scp) value. It showed antioxidant activity, a prolonged release time, non-toxic with LC50 > 1000 and a cytotoxic effect on cancer cells. Results showed IC50 values starting at 5.8 μg mL−1 for the free lapachol and 12.3 μg mL−1 for the lapachol-loaded. Therefore, the system presents a potential for anticancer application.

We show that by design we can create a new resist materials for electron beam lithography, based on a supramolecular assembly. The initial studies show that via this supramolecular approach high resolution structures can be written which showunprecedented selectivity when exposed to etch conditions involving plasmas.

A Radio Frequency Identification (RFID) Tag is designed for threshold detection of certain chemical vapors. The vapor presence is signaled to the reader by a digital alert and communication between the tag and reader is not interrupted. The detection mechanism comprises an inkjet printed conducting track on an elastomer that swells in response to vapor exposure. The expanded track breaks and triggers a tamper detection circuit integrated into the RFID tag transponder chip

Field-emission devices are promising candidates to replace silicon fin field-effect transistors as next-generation nanoelectronic components. For these devices to be adopted, nanoscale field emitters with nanoscale gaps between them need to be fabricated, requiring the transfer of, for example, sub-10 nm patterns with a sub-20 nm pitch to substrates like silicon and tungsten. New resist materials must therefore be developed that exhibit the properties of sub-10 nm resolution and high dry etch resistance. A negative tone, metal–organic resist is presented here. It can be patterned to produce sub-10 nm features when exposed to helium ion beam lithography at line doses on the order of tens of picocoulombs per centimeter. The resist was used to create 5 nm wide, continuous, discrete lines spaced on a 16 nm pitch in silicon and 6 nm wide lines on an 18 nm pitch in tungsten, with line edge roughness of 3 nm. After the lithographic exposure, the resist demonstrates high resistance to silicon and tungsten dry etch conditions (SF_6 and C_4F_8 plasma), allowing the pattern to be transferred to the underlying substrates. The resist’s etch selectivity for silicon and tungsten was measured to be 6.2:1 and 5.6:1, respectively; this allowed 3 to 4 nm thick resist films to yield structures that were 21 and 19 nm tall, respectively, while both maintained a sub-10 nm width on a sub-20 nm pitch.

Fouling of processing units because of asphaltene deposition is a common phenomenon that interrupts the operation of oil refineries. In this study, the deposition behavior of a model archipelago asphaltene was investigated in the temperature range of 150 oC to 350 oC. For a fixed surface chemistry, the differences in deposit chemistry with fouling temperature is a function of the thermochemical properties of the model asphaltene. Under static high pressure and high temperature fouling conditions, both surface roughness and chemistry play an important role in asphaltene deposition. Rough surfaces are shown to develop larger deposits because of less restrictive physical barriers to inhibit deposit growth. Passivating the surface with an alumina chemistry significantly reduces the impact of surface roughness, as well as the total amount of deposition. This beneficial effect of using a protective alumina chemistry is attributed to its high thermal stability and low diffusivity that inhibit the uncontrolled formation of thiolate and sulfide deposits that are found on unpassivated steels. Instead, alumina modifies the surface reaction to a self-limiting chemisorption and oxidation process that produces thin sulfate deposits at the surface. With further consideration to the reactive species present in solution, the findings of this study may be extended to determine suitable surface conditions that mitigate asphaltene fouling.

Fouling of oil-exposed surfaces remains a crucial issue as a result of the continued importance of oil as the world’s primary energy source. The key perpetrators in crude oil fouling have been identified as asphaltenes, a poorly described mixture of diverse polyfunctional molecules that form part of the heaviest fractions of oil. Asphaltenes are responsible for a decrease in oil production and energy efficiency and an increase in the risk of environmental hazards. Hence, understanding and managing systems that are prone to fouling is of great value but constitutes a challenge as a result of their complexity. In an effort to reduce that complexity, a study of a synthesized foulant of archipelago structure is presented. A critical perspective on previously described solubility and aggregation mechanisms (e.g., critical nanoaggrerate concentration and critical clustering concentration) is offered because the characterized system favors a continuous distribution of n-mers instead. A battery of experimental and modeling techniques have been employed to link the bulk and interfacial behavior of a representative foulant monomer to effective fouling mitigation strategies. This systematic approach defines a new multiscale methodology in the investigation of fouling systems.

In this paper we demonstrate the potential of high molecular weight hyperbranched methacrylate polymers for inkjet printing. Using the Strathclyde method, a series of hyperbranched poly (methylmethacrylate) polymers of increasing branch density were prepared. All hyperbranched polymers show both a significantly greater maximum printable concentration compared to equivalent linear polymers with implications for faster print speed. Increasing chain branching above a critical value across the molecular weight distribution was found to result in suppression of molecular weight degradation. This resistance to molecular degradation is because the longest chain segment being much smaller, such that upon jetting the polymer rapidly retains its thermodynamically stable Gaussian coil conformation and the full force of the constrictional flow in the print head is not passed on to the polymer and degradation is supressed. We further go on to show using Electron Paramagnetic Resonance that degradation occurs via a free radical chain scission mechanism.

Wearable sensors placed behind-the-ear are emerging as being very promising for unobtrusive long term monitoring. Factors such as gait, electroencephalography (EEG), and ballistocardiography (BCG) can all be measured from behind-the-ear in a socially acceptable hearing aid basedform factor. Previous works have investigated the recording of electrocardiography (ECG) from the ear, but generally with one electrode placed some distance away from the ear itself. This paper uses recently introduced tattoo electrodes to investigate whether ECG components can indeed be measured from behind a single ear. Compared to a reference photophelsmography (PPG) device we show that the fundamental heart beat frequency is present in behind-the-ear ECG only in half of the cases considered. In contrast the second harmonic is present in all records and could allow the extraction of heart rate to within a few beats-per-minute accuracy. Further signal processing work is required to allow the automated extraction of this, particularly when working with short time windows of data, but our results characterize the signal and demonstrate the principle of behind-the-ear ECG collected from a single ear.

A new class of resist materials has been developed that is based on a family of heterometallic rings. The work is founded on a Monte Carlo simulation that utilizes a secondary and Auger electron generation model to design resist materials for high resolution electron beam lithography. The resist reduces the scattering of incident electrons to obtain line structures that have a width of 15 nm on a 40 nm pitch. This comes at the expense of lowering the sensitivity of the resist, which results in the need for large exposure doses. Low sensitivity can be dramatically improved by incorporating appropriate functional alkene groups around the metal-organic core, for example by replacing the pivalate component with a methacrylate molecule. This increases the resist sensitivity by a factor of 22.6 and demonstrates strong agreement between the Monte Carlo simulation and the experimental results. After the exposure and development processes, what remains of the resist material is a metal-oxide that is extremely resistant to silicon dry etch conditions; the etch selectivity has been measured to be 61:1.

Monoterpenoids offer potential as biocatalytically derived monomer feedstocks for high-performance renewable polymers. We describe a biocatalytic route to lactone monomers menthide and dihydrocarvide employing Baeyer-Villiger monooxygenases (BVMOs) from Pseudomonas sp. HI-70 (CPDMO) and Rhodococcus sp. Phi1 (CHMOPhi1) as an alternative to organic synthesis. The regioselectivity of dihydrocarvide isomer formation was controlled by site-directed mutagenesis of three key active site residues in CHMOPhi1. A combination of crystal structure determination, molecular dynamics simulations, and mechanistic modeling using density functional theory on a range of models provides insight into the origins of the discrimination of the wild type and a variant CHMOPhi1 for producing different regioisomers of the lactone product. Ring-opening polymerizations of the resultant lactones using mild metal-organic catalysts demonstrate their utility in polymer production. This semisynthetic approach utilizing a biocatalytic step, non-petroleum feedstocks, and mild polymerization catalysts allows access to known and also to previously unreported and potentially novel lactone monomers and polymers.

In dilute aqueous solution unimers of Pluronic F127 associate to form micelles. In more concentrated solution, micelles pack to form high-modulus gels. Our interest is the effect of addition of 10–30 wt % low molecular weight PPG400 on the micellization and gelation of solutions of F127. DLS was used to determine the apparent size of the micelles (rh,app). The critical micelle concentration (cmc) using the dye solubilization method of F127 in PPG400 solutions was studied. Visual observation was carried out to detect gel formation in concentrated solutions and the onset of clouding and turbidity, as the temperature was raised. Oscillatory rheometry was used to confirm the formation of high-modulus gels and provide values of elastic moduli (G′max) over a wide temperature range. SAXS was used to determine gel structure. Our results for the hydrophobic adduct PPG400 were compared with literature values for the hydrophilic adduct PEG6000.

Pluronics® molecules self-assemble in aqueous solution providing a core/shell architecture that improves the solubility of hydrophobic drugs. Binary mixtures of Pluronics® have been studied as drug nanocarriers in order to combine their advantages, like high colloidal stability, small particle size and good solubilisation capacity (Scp). In this work we studied Pluronics® binary mixture, P123 and F127, as nanocarriers of the hydrophobic drug griseofulvin. P123 (E21P67E21) shows a relative good Scp, whereas F127 (E98P67E98) shows a good colloidal stability. According to data, these binary mixtures form stables nano-sized comicelles in aqueous solution. The Scp of the P123/F127 systems at 25 and 37 °C was monitored by UV/Visible spectroscopy, showing good results at both temperatures, as would be expected, since P123/F127 have similar length hydrophobic block. Hydrophobic-dependence and temperature-responsive of the systems were evaluated by CMC, particle size and colloidal stability. Hence, stables P123/F127 comicelles may have potencial as hydrophobic drug delivery.

This chapter introduces the fundamental concepts necessary to understand polymers in inkjet formulation: molecular weight, their solution properties and their behaviour under flow. The formulation challenges of printing high molecular weight polymers arising from these flow behaviours are introduced along with the degradation reactions occurring in both drop on demand (DOD) and continuous inkjet (CIJ) systems for synthetic polymers and naturally occurring polymers showing tertiary structure.

Results are reported for the first time on the possibility and cause of polymer degradation in a full commercial inkjet printer. The behaviour of three linear poly(methyl methacrylate) (PMMA) samples, having M w 90, 310 and 468 kDa respectively, in a continuous inkjet (CIJ) Domino A-Series+ printer is investigated and compared with earlier reported results for two experimental drop on demand (DOD) printers, a Dimatix DMP-2800 and a Microfab single nozzle glass capillary. Despite all three printheads having equivalent strain rate at the nozzle tip ( e ) no degradation is observed within the CIJ head alone whereas single pass degradation is observed in both DOD printheads. This can be attributed to a consequence of a number of factors including the slightly greater nozzle diameter, and different nozzle geometry, which includes cone angle and nozzle cylinder length, for CIJ, the different mode of drop generation or the higher polymer concentration investigated. It should also be noted that the flow through the CIJ nozzle is continuous, where it is pulsed in the case of DOD. The calculated maximum strain rates are similar, but in DOD it is being periodically ramped up and switched off. The main source of polymer degradation in CIJ printing through a CIJ Domino A-Series+ printer is found to be the continuous recycling of ink through the pump resulting in mechano-chemical polymer degradation. Molecular weight degradation proceeds by random scission, and is obtained at the lower shear rates experience as a consequence of the longer residence time due to mechano-chemical damage in the pump. These results have significance in the total design of inkjet systems for the delivery of high molecular weight polymers and materials sensitive to mechano-chemical degradation and highlight the need for careful consideration when moving from laboratory based print tools to full scale application.

The solvent- and concentration-dependent photostability of TIPS-pentacene in solution is directly related to the efficiency of singlet-state deactivation by a combination of pairwise interactions and quenching at low concentration. At higher concentrations, further increases in stability suggest the onset of aggregation.

Colouration of poly (lactic acid) textile materials using pigments is particularly interesting because of the commercial importance of pigment prints and the sensitivity of poly (lactic acid) fibres to aqueous treatment; however the processing requires optimisation because of the fibre's heat sensitivity. In this study, poly (lactic acid) fabrics were screen pigment printed and thermally cured at different temperatures, ranging from 120 °C to 150 °C, and curing times, from 3 min to 5 min. Surface sensitive X-ray Photoelectron Spectroscopy (XPS) was used to probe the nature of the outer 1–10 nm of the untreated and heat treated poly (lactic acid) surfaces, in order to characterise the surface functionalities and elemental composition. In addition, the effect of curing temperature and time on the performance characteristics of pigment printed poly (lactic acid) fabrics in terms of colour fastness, burst strength, abrasion resistance, Kawabata Evaluation System for Fabrics (KES-F) parameters and surface morphology were evaluated and optimum curing conditions for the pigment printing of poly (lactic acid) fabrics were established.

An all-vacuum evaporated approach to the roll-to-roll (R2R) fabrication of organic electronic circuits is being developed for potential applications in, for example, display backplanes and integrated security tagging for packaging. As part of an on-going development process, we are now addressing the question of circuit design and simulation. Here we describe the first step in this process, namely the extraction of parameters from experimentally-obtained output and transfer characteristics of vacuum produced, thin film transistors based on the organic semiconductors pentacene and dinaphtho[2,3-b:2′3′-f] thieno[3,2-b]thiophene (DNTT). For this we use Silvaco's Universal Thin Film Transistor (UOTFT) Model (Level=37) so that the extracted parameters may be used directly with Silvaco's Gateway circuit simulation software. © 2013 IEEE.

The application of a new benzannulation reaction for the regiocontrolled synthesis of functionalized chrysenes is reported. The initial benzannulation and the subsequent halogen displacement reactions are both highly regiospecific, which thereby enables the regiocontrolled synthesis of a variety of 4,10-disubstituted chrysenes from commercially available 1,5-dihydroxynaphthalene.

Chitosan degradation in 0.1 M acetic acid solution by microwave radiation alone (without any additives and initiators) is reported. At the condition of reduced thermal effects of microwave heating degradation manifested most of typical features associated with mechanical (and or mechanochemical) degradations induced by shear forces, in this particular case oscillating molecules. At the absorbed energy dose of 9 MJ kg−1 chitosan in 1% w/v solution degrades within 20 min to the weight average molecular weight of 30 kDa. Comparative evaluation of degradation yield of chain scission (Gs) with other high energy radiations such as ultraviolet- and gamma radiation showed microwave to be the least efficient, but considering the environmental impact and low running costs it presents a viable alternative to obtain targeted molecular weights of charged polysaccharides.

High-throughput synthetic and screening methods have been used to prepare and evaluate caesium, cobalt and strontium selective sequestering agents derived from aza-crown ethers. Storage phosphor autoradiography was the screening method used to determine potential lead compounds. The most effective complexants for Cs+ have a very high selectivity over potassium ions and will bind picomolar quantities of Cs+ in the presence of mM K+. The binding and selectivity of these compounds with 60Co and 90Sr have also been investigated and selectivity was also determined with tap water and Ca2+, respectively. Experiments with tap water spiked with 137Cs and 60Co were carried out to confirm the decontamination capabilities of some of our compounds and a good correlation between autoradiography and these results were found. © 2008 The Royal Society of Chemistry.

Roll-to-roll (R2R) production of organic transistors and circuits require patterned deposition of organic layers at high deposition rate. Here we demonstrate a vapour-jet process for the rapid deposition of the organic semiconductor dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT). The deposition rate achieved, equivalent to ∼200 nm/s onto a stationary substrate, was several orders of magnitude faster than ordinary thermal evaporation. Nevertheless, transistor yield was 100% with an average mobility of 0.4 cm2/V in a single pass deposition onto a substrate moving at 0.15 m/min. We also demonstrate a vacuum, high rate R2R-compatible process for surface-functionalising a gate dielectric layer with lauryl acrylate which enabled an all-vacuum route to the fabrication of a five-stage ring oscillator.

Using an electrostatic-based super inkjet printer we report the high-resolution deposition of polyelectrolyte macroinitiators and subsequent polymer brush growth using SI-ARGET-ATRP. We go on to demonstrate for the first time a submicron patterning phenomenon through the addition of either a like charged polyelectrolyte homopolymer or through careful control of ionic strength. As a result patterning of polymer brushes down to ca. 300 nm is reported. We present a possible mechanistic model and consider how this may be applied to other polyelectrolyte-based systems as a general method for submicron patterning.

This Letter presents an investigation of radio frequency identification tags integrated with sticking plasters. Conductive ink is used in the fabrication to provide good compatibility with the plaster in terms of flexibility. The tag is proposed for use as a wireless platform for long-term patient monitoring in hospital environments. A motion capture system is used to test the directions in which the tag can be read to inform a diversity study establishing the number of tags required on-body to ensure reliable reading for applications such as medical monitoring. Tag diversity performance with various body movements is also studied. It is established that four tags give all round body coverage with only 4% loss in coverage for vertically polarised tags should one of them fail.

Additive fabrication of electromagnetic structures by inkjet printing technology is both cost effective and compatible with a wide range of environmentally friendly substrates, enabling the fabrication of frequency-selective surface (FSS) arrays with line dimensions less than 0.1 mm, which is difficult to achieve with conventional subtractive techniques. Several approaches, such as savings in ink by depositing it at the edges of dipole elements where the surface current tends to maximize, have been investigated in order to produce low-cost frequency-selective panels with acceptable level of isolation. The FSS transmission characteristics were improved by jetting multiple ink layers on the whole elements and at the edges. The electrical resistance of various arrays have been measured and analyzed and has been used to assess the performances of the FSS.