Polymer Patterns Research Articles

Continuous and Patterned Conducting Polymer Coatings on Diverse Substrates: Rapid Fabrication by Oxidant-Intermediated Surface Polymerization and Application in Flexible Devices

Conducting polymer coatings and patterns are the most important forms of these materials for many practical applications, but a simple and efficient approach to these forms remains challenging. Herein, we report a universal oxidant-intermediated surface polymerization (OISP) for the fabrication of conducting polymer coatings and patterns on various substrates. A coating or pattern composed of densely packed colloidal V2O5·nH2O nanowires is deposited on the substrate via spin coating, dip coating, or printing, which is converted into a conducting polymer one after in situ oxidation polymerization. The polymerization occurs selectively on the V2O5·nH2O coatings, and high-quality polypyrrole, polyaniline, and poly(3,4-ethylenedioxythiophene) coatings and patterns on planar and curved polymeric, metallic, and ceramic substrates are obtained in a fast reaction rate similar to the electrochemical polymerization. The mechanistic study reveals that the method relies on the excellent processability and formability of V2O5·nH2O nanowires, which is further explained by their large aspect ratio and surface activity. A flexible gas sensor array comprising three individual sensors made of different conducting polymers is fabricated using oxidant-intermediated surface polymerization, and it is successfully used to distinguish various analyte vapors. The method developed here will provide a powerful tool for the fabrication of conducting polymer-based devices.

Electrochemically switchable polymerization from surface-anchored molecular catalysts.

Redox-switchable polymerizations of lactide and epoxides were extended to the solid state by anchoring an iron-based polymerization catalyst to TiO2 nanoparticles. The reactivity of the molecular complexes and their redox-switching characteristics were maintained in the solid-state. These properties resulted in surface-initiated polymerization reactions that produced polymer brushes whose chemical composition is dictated by the oxidation state of the iron-based complex. Depositing the catalyst-functionalized TiO2 nanoparticles on fluorine-doped tin oxide resulted in an electrically addressable surface that could be used to demonstrate spatial control in redox-switchable polymerization reactions. By using a substrate that contained two electrically isolated domains wherein one domain was exposed to an oxidizing potential, patterns of surface-bound polyesters and polyethers were accessible through sequential application of lactide and cyclohexene oxide. The differentially functionalized surfaces demonstrated distinct physical properties that illustrated the promise for using the method to pattern surfaces with multiple, chemically distinct polymer brushes.

Impact of the process conditions on polymer pattern morphology during spin coating over topological surfaces.

Micro and nanofabrication techniques depend on the technology of polymer film casting. Spin coating is a relatively robust method to develop uniform polymer films over the substrate surface. However, polymer casting over a topographically prepatterned surface using the spin coating technique is challenging because of the complex transport phenomena involved in the process. Apart from the substrate wettability and the polymer composition, the geometry of the substrate prepatterns affects the polymer phase separation characteristics and thus the morphology of the polymer pattern. In this work the phase separation dynamics during the spinodal decomposition of a polymer-solvent system in a spin coating process is mathematically investigated. The effect of the prepattern topography, substrate wettability, spin-coating rotational speed, and polymer composition on the phase separation dynamics is investigated. The results reveal that the periodicity and phase difference of the polymer peaks with the topography are dependent on the geometric parameters and substrate wettability. The impact of the rotational motion, on the polymer film, is restricted by the surface roughness (due to the topological prepatterns). On reducing the polymer fraction in the solution, the transition from a uniform coating to film defects to isolated patches (wetting to dewetting) occurs. The surface wettability plays a crucial role in topology directed dewetting, which is not observed in flat substrates.

POSTBIOTIC AND OTHER PROTECTIVE MOLECULES RECOGNIZING AND BINDING GLYCOCONJUGATES IN MUCOSAL ORGANS

New aspects of human mucosal cavity protection systems are under consideration. On the basis of own data it was suggested that mucosal cavities function as mucosal organs. New players of mucosal organ were proposed. They included system probiotic lectins and probiotic microorganisms, and system synthetic polymeric multivalence pattern glycoconjugates. Lectins and glycoconjugates (mucin-like or imitating, antigens, polysaccharides and other high molecular mass metabolites and postbiotics) were suggested to communicate to other glycoconjugates-recognizing molecules and receptors of the human higher hierarchic protection systems.
 Concept of functioning mucosal organs is supported by own proposals, strategies, approaches, methods and algorithms. The data are useful for constructing biotope ordered pro/synbiotic microbiocenoses for application in medical biotechnology.

Impact of Chlorination Patterns of Naphthalenediimide-Based Polymers on Aggregated Structure, Crystallinity, and Device Performance of All-Polymer Solar Cells and Organic Transistors.

The aggregation properties of conjugated polymers can play a crucial role in their thin film structures and performance of electronic devices. Control of these aggregated structures is particularly important in producing efficient all-polymer solar cells (all-PSCs), considering that strong demixing of the polymer donor and polymer acceptor typically occurs during film formation because of the low entropic contribution to the thermodynamics of the system. Here, three naphthalenediimide (NDI)-based polymer acceptors with different backbone chlorination patterns are developed to investigate the effect of the chlorination patterns on the aggregation tendencies of the polymer acceptors, which greatly influence their crystalline structures, electrical properties, and device performances of the resultant all-PSCs and organic field-effect transistors (OFETs). The counterparts of NDI units, dichlorinated bithiophene (Cl2T2), monochlorinated bithiophene (ClT2), and dichlorinated thienylene-vinylene-thienylene (Cl2TVT), are employed to synthesize a series of P(NDIOD-Cl2T2), P(NDIOD-ClT2), and P(NDIOD-Cl2TVT) polymers. The P(NDIOD-Cl2T2) polymer takes advantage of strong noncovalent bonding induced by its chlorine substituents, resulting in the formation of optimal face-on oriented crystalline structures which are suitable for efficient all-PSC devices. In comparison, the P(NDIOD-Cl2TVT) polymer forms bimodal crystalline structures in thin films to yield optimal performances in the resultant OFETs. When the three chlorinated polymers are applied to all-PSCs with the PBDTTTPD polymer donor, P(NDIOD-Cl2T2) achieves a maximum power conversion efficiency (PCE) of 7.22% with an appropriate blend morphology and high fill factor, outperforming P(NDIOD-ClT2) (PCE = 4.80%) and P(NDIOD-Cl2TVT) (PCE = 5.78%). Our observations highlight the effectiveness of the chlorination strategy for developing efficient polymer acceptors and demonstrate the important role of polymer aggregation in modulating the blend morphology and all-PSC performance.

A Novel Approach for Effective Alteration of Morphological Features of Polyaniline through Interfacial Polymerization for Versatile Applications.

Morphological characteristics of any nanomaterial are critical in defining its properties. In this context, a method to control morphological parameters of polyaniline (PANI) has been investigated by producing its composite with gold nanoparticles (AuNPs). Herein, we report for the first time the successful control on the physical/chemical properties of PANI composites synthesized via interfacial polymerization through functionalization of its AuNP composite component with citrate, ascorbate, glutathione (GSH), and cetyl trimethyl ammonium bromide (CTAB). A significant difference in the polymerization pattern, morphologies, and electrical properties was recognized in these composites according to the functionality of the modified AuNPs. The obtained composites of AuNPs/PANI exhibited highly diverse morphologies (e.g., nodule, hollow hemisphere, flake, and spider-web galaxy type) and electrical characteristics according to functionalization. Hence, this study is expected to offer better insight into control of the polymerization pattern of AuNP/PANI composites and their associated properties.

Patterned Piezoelectric Scaffolds for Osteogenic Differentiation.

The morphological clues of scaffolds can determine cell behavior and, therefore, the patterning of electroactive polymers can be a suitable strategy for bone tissue engineering. In this way, this work reports on the influence of poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) electroactive micropatterned scaffolds on the proliferation and differentiation of bone cells. For that, micropatterned P(VDF-TrFE) scaffolds were produced by lithography in the form of arrays of lines and hexagons and then tested for cell proliferation and differentiation of pre-osteoblast cell line. Results show that more anisotropic surface microstructures promote bone differentiation without the need of further biochemical stimulation. Thus, the combination of specific patterns with the inherent electroactivity of materials provides a promising platform for bone regeneration.

Self-assembly for electronics

Abstract

Photopatternable and Rewritable Epoxy‐Anhydride Vitrimers

The present work highlights a new approach to write, erase, and rewrite micropatterns into the same region of covalent adaptable polymer networks. Thermal curing of an epoxy-terminated o-nitrobenzyl ester (o-NBE) derivative with hexahydrophthalic anhydride in the presence of 1,5,7-triazabicyclo[4.4.0]dec-5-ene yields a dynamic covalent network, whose solubility is locally controlled by irradiation with ultraviolet (UV) light. The photolysis of the o-NBE chromophores enables a well-defined cleavage of the epoxy-anhydride network, and the formation of soluble photolysis products is confirmed by sol-gel analysis. The photo-induced change in solubility is exploited to inscribe micropatterns by photolithographic techniques and after development in an organic solvent positive tone structures with a feature size of 20µm are obtained. Due to the thermo-activated exchange reactions of the hydroxyl ester links and the related macroscopic reflow, the polymer patterns are fully erased at temperatures well above the topological freezing transition of the vitrimer network. The regenerated film has a smooth surface topology and can be reused to inscribe new micropatterns via mask lithography.

Multi-Stage Organic Logic Circuits Using Via-Hole-Less Metal Interconnects

Multi-metal interconnection is a crucial technology for the development of large-scale integrated circuits (ICs). However, organic semiconductors are not robust enough to be compatible with conventional lithography-and-etching-based via-forming methods. Thus, an alternative metal interconnect method is required for successful organic IC implementation. In-situ patterning of a dielectric polymer through a shadow mask while depositing in vapor phase possibly addresses the issues in both solvent susceptibility and process complexity. Here we report multi-stage organic logic circuits with a multi-level metal interconnection scheme based on patterned interlayer dielectrics via vapor phase deposition. We implement an exclusive OR circuit composed of four 2-input NAND gates and three-level metal interconnections to demonstrate the potential of the proposed solvent-free metal interconnection scheme.

SERS-active linear barcodes by microfluidic-assisted patterning

Simple, low-cost, robust, and scalable fabrication of microscopic linear barcodes with high levels of complexity and multiple authentication layers is critical for emerging applications in information security and anti-counterfeiting. This manuscript presents a novel approach for fabrication of microscopic linear barcodes that can be visualized under Raman microscopy. Microfluidic channels are used as molds to generate linear patterns of end-grafted polymers on a substrate. These patterns serve as templates for area-selective binding of colloidal gold nanoparticles resulting in plasmonic arrays. The deposition of multiple taggant molecules on the plasmonic arrays via a second microfluidic mold results in a linear barcode with unique Raman fingerprints that are enhanced by the underlying plasmonic nanoparticles. The width of the bars is as small as 10 μm, with a total barcode length on the order of 100 μm. The simultaneous use of geometric and chemical security layers provides a high level of complexity challenging the counterfeiting of the barcodes. The additive, scalable, and inexpensive nature of the presented approach can be easily adapted to different colloidal nanomaterials and applications.

The influence of arm composition on the self-assembly of low-functionality telechelic star polymers in dilute solutions

We combine synthesis, physical experiments, and computer simulations to investigate self-assembly patterns of low-functionality telechelic star polymers (TSPs) in dilute solutions. In particular, in this work, we focus on the effect of the arm composition and length on the static and dynamic properties of TSPs, whose terminal blocks are subject to worsening solvent quality upon reducing the temperature. We find two populations, single stars and clusters, that emerge upon worsening the solvent quality of the outer block. For both types of populations, their spatial extent decreases with temperature, with the specific details (such as temperature at which the minimal size is reached) depending on the coupling between inter- and intra-molecular associations as well as their strength. The experimental results are in very good qualitative agreement with coarse-grained simulations, which offer insights into the mechanism of thermoresponsive behavior of this class of materials.

Influence of Scale Factor on Structuring of Epoxy Polymer Products under the Action of Thermal Energy

The structural features of epoxy polymer samples of different thicknesses under the influence of thermal energy are studied. The structure of fracture patterns of epoxy polymers, which are intensively structured in the thermal field, is investigated. The optimum temperature and duration of exposure are determined, which allows intensive production of products based on epoxy polymers with high physical and mechanical characteristics.

Replace wooden pattern to polymer pattern by 3D printing

Purpose of this paper is replacing wooden pattern to the polymer by 3D printing, Plastic is most common raw material for 3D printing for making any type of item from 3D printing the item made with this procedure incorporate work area. Utensils, container and action figure accessible in straightforward structure plastic fibre are sold on spool and has a matte and bright it is also available in transparent form and bright colour.Sand casting is an ancient process of manufacturing it is integrated through the 3D printing for making pattern, in conventional sand casting the component make by pouring molten metal into moulds structure is made by compacting is around (for example - set in a form of box) after the compaction pattern is pulled back from where liquid metal is poured Pattern is making by wood because it available easily and machining, it has high compressive strength to its grain that is suitable for compaction moulding there is less failure during the operation. But it not reduces the environment effect that why we are use polymer.Polymer recycle and reduce the environment effect which is occur from the polymeric waste 3D printers use that west of raw materials into useful product.

Arrays of Plasmonic Nanoparticles Assembled on Patterns of Polymer Brushes Fabricated by Soft Lithography

This work employed end-grafted poly ethylene glycol PEG and hydroxyl-terminated poly 2-vinylpyridine P2VP polymer chains for selective immobilization and patterning of plasmonic nanoparticles NPs . A soft lithographic method which called micromolding in capillaries MIMIC used in this study. The polymers are deposited the capillary flow by the channels which formed by an elastomeric mold and substrate. The localized coatings are referred as polymer brushes and show great promise in the assembly of NPs due to the tunable interaction between the polymer chains and particles. The results show that the width of patterns defined by the channels is smaller than 1.5 µm with a length of around 0.5 cm. Also, the heights of the patterns are ~3.5 nm for P2VP and ~10 nm for PEG. The fabricated structures exhibited high levels of plasmonic activity and surface enhanced Raman scattering due to the immobilized Au NPs. The patterning polymer brushes and plasmonic NPS over large areas by a low-cost process show great promise for a variety of applications that range from molecular sensors to biotechnology

2-Anilinoquinoline based arylamides as broad spectrum anticancer agents with B-RAFV600E/C-RAF kinase inhibitory effects: Design, synthesis, invitro cell-based and oncogenic kinase assessments.

Prompted by the urgent demand for identification of new anticancer agents with improved potency and efficacy, a new series of arylamides incorporating the privileged 2-anilinoquinoline scaffold has been designed, synthesized, and biologically assessed. Aiming at extensive evaluation of the target compounds' potency and spectrum, a panel of 60 clinically important cancer cell lines representing nine cancer types has been used. Compounds 9a and 9c, with piperazine substituted phenyl ring, emerged as the most active members surpassing the anticancer potencies of the FDA-approved drug imatinib. They elicited sub-micromolar or one-digit micromolar GI50 values over the majority of tested cancer cells including multidrug resistant (MDR) cells like colon HCT-15, renal TK-10 and UO-31, and ovarian NCI/ADR-RES. Invitro mechanistic study showed that compounds 9a and 9c could trigger morphological changes, apoptosis and cell cycle arrest in HCT-116 colon cancer cells. Besides, compound 9c altered microtubule polymerization pattern in a similar fashion to paclitaxel. Kinase screening of 9c disclosed its inhibitory activity over B-RAFV600E and C-RAF kinases with IC50 values of 0.888μM and 0.229μM, respectively. Taken together, the current report presents compounds 9a and 9c as promising broad-spectrum potent anticancer candidates, which could be considered for further development of new anticancer drugs.

Marangoni instability in the linear Jeffreys fluid with a deformable surface

Advantages of thermocapillary techniques over other approaches to polymer patterning have been recently recognized and will promote them to further expansion and development. In this perspective, a study of Marangoni instability in a layer of a viscoelastic liquid with a deformable interface is of great importance. Its linear stability analysis shows the presence of (and competition among) the long-wave stationary, short-wave stationary, and oscillatory modes, which leads to the emergence of codimension-two and codimension-three points in the parameter space.

Molecular Imprinted Based Quartz Crystal Microbalance Sensors for Bacteria and Spores

A molecular imprinting strategy was combined with mass-sensitive transducers to generate robust and reliable biomimetic sensor systems for the detection of bioparticles. The patterning of polymers with bioanalytes enabled us to detect Escherichia coli (E. coli) bacteria with quartz crystal microbalance (QCM). The QCM sensor results were compared with direct Atomic Force Microscopy (AFM) measurements—bacteria cells adhering to the sensor coatings were counted. The recognition sites generated by Bacillus subtilis (B. subtilis) spores could successfully and reversibly recognize the template analyte and ensured rapid sensing. Cross sensitive measurements clearly showed the advantage of the molecular imprinting strategy, by which spores of Bacillus species (subtilis and thuringiensis) could easily be differentiated and selectively detected. The growth of B. subtilis from its spores was observed at 42 °C in appropriate nutrient solution of glucose and ammonium sulfate over a period of 15 h. Moreover, the growth of B. subtilis bacteria from its respective spores was studied by increasing the glucose concentration until saturation effect of the sensor. The polymeric sensor coatings were patterned to fix the B. subtilis in order to investigate osmotic effects according to a frequency response of 400 Hz by altering the ionic strength of 0.1 M.

Graphene Templated DNA Arrays and Biotin-Streptavidin Sensitive Bio-Transistors Patterned by Dynamic Self-Assembly of Polymeric Films Confined within a Roll-on-Plate Geometry.

Patterning of surfaces with a simple strategy provides insights into the functional interfaces by suitable modification of the surface by novel techniques. Especially, highly ordered structural topographies and chemical features from the wide range of interfaces have been considered as important characteristics to understand the complex relationship between the surface chemistries and biological systems. Here, we report a simple fabrication method to create patterned surfaces over large areas using evaporative self-assembly that is designed to produce a sacrificial template and lithographic etch masks of polymeric stripe patterns, ranging from micrometer to nanoscale. By facilitating a roll-on-plate geometry, the periodically patterned surface structures formed by repetitive slip-stick motions were thoroughly examined to be used for the deposition of the Au nanoparticles decorated graphene oxide (i.e., AuNPs, ~21 nm) and the formation of conductive graphene channels. The fluorescently labeled thiol-modified DNA was applied on the patterned arrays of graphene oxide (GO)/AuNPs, and biotin-streptavidin sensitive devices built with graphene-based transistors (GFETs, effective mobility of ~320 cm2 V−1 s−1) were demonstrated as examples of the platform for the next-generation biosensors with the high sensing response up to ~1 nM of target analyte (i.e., streptavidin). Our strategy suggests that the stripe patterned arrays of polymer films as sacrificial templates can be a simple route to creating highly sensitive biointerfaces and highlighting the development of new chemically patterned surfaces composed of graphene-based nanomaterials.

Development of cellulose-based conductive fabrics with electrical conductivity and flexibility.

This study aimed to produce cellulose-based conductive fabrics with electrical conductivity and flexibility. Bacterial cellulose (BC) and three chemical cellulose (CC), namely methyl cellulose (MC), hydroxypropyl cellulose (HPMC) and carboxymethyl cellulose (CMC) were in situ polymerized with aniline and the four conductive cellulose fabrics were compared and evaluated. Matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy analysis confirmed that three CC-PANI composites displayed longer and more stable polymerization pattern than BC-PANI because of the different polymerization method: bulk polymerization for BC-PANI and emulsion polymerization for CC-PANI, respectively. The electrical conductivity of BC-PANI and CC-PANI were ranging from 0.962 × 10−2 S/cm to 2.840 × 10−2 S/cm. MC-PANI showed the highest electrical conductivity among the four conductive cellulose fabrics. The flexibility and crease recovery results showed that MC-PANI had the highest flexibility compared to BC-PANI, HPMC-PANI, and CMC-PANI. These results have confirmed that the electrical conductivity and flexibility were influenced by the type of cellulose, and MC-PANI was found to have the best performance in the electrical conductivity and flexibility.