Innovative Fabrication Research Articles

Solvothermal-assisted graphene encapsulation of SiC nanoparticles: A new horizon toward toughening aluminium matrix nanocomposites

Agglomeration of ceramic nanoparticles is a key challenge during manufacturing aluminium matrix composites in both solid and liquid methods. This study presents an innovative fabrication route to diminish the agglomeration of SiC nanoparticles using graphene encapsulating method stimulated by a solvothermal process. The produced SiC nanoparticles were then incorporated into A357 molten alloy using a liquid processing route. HRTEM investigations have shown the uniform distribution of SiC nanoparticles wrapped by onion-liked graphene shells within the matrix of composite, conferring 273% and 400% enhancement in yield strength and tensile ductility, respectively, compared to the unreinforced one. This is attributed to the manipulation of solidification mechanism of SiC nanoparticles from pushing to engulfment, ensued from imparting higher thermal conductivity to these particles by onion-liked graphene sheets. Fractographic observations have revealed the transgranular facture mode activated due to nano-void coalescence fracture mechanism in composites reinforced with graphene sheets associated with prolonged ductility. A devised analytical strengthening model has also demonstrated the profound efficacy of thermal activated dislocation mechanism in fortifying the matrix, brought about by the exceptional negative thermal expansion coefficient of graphene sheets.

Development of a Weaving Method for Spatial Two-Layer Innovative Structure Linen Fabric

*Joint-stock „A grupė“ Ruklos 14, LT-55198 Jonava, Lithuania Abstract During the global technological progress, including in the textile field, it has become necessary to look for innovative solutions to make fabric designs that can be characterised by special texture and relief, as well as opportunities to create them with modern weaving looms. Most commonly, such innovative fabric structures can be woven by using several different methods, and sometimes by several weaving looms of different designs and uses. Thus this article provides an introduction and thorough analysis of two weaving methods used to weave such linen fabrics of innovative structure by modern computerised looms of different types and designs: the terry gripper weaving loom Smit GS940F and smooth fabric gripper jacquard weaving loom Dornier PTS 6/J C. In both cases the structure effects of those fabrics were rather similar. Most fabric properties are better for the fabrics woven by the second technique. For that kind of fabric structure it is therefore advisable to use the second weaving method, i. e. the smooth fabric gripper weaving loom Dornier PTS 6/J C. Smooth fabric looms are more versatile, and they do not require a set of specific complex mechanisms that are usually used on a terry gripper weaving loom.

Application of biomimicry in textiles

Nature has created excellent technologies around us, and as such, it is the chief mentor to humans on creativity and technology development. Nature uses fibre as a building block - natural structures like wood, bamboo, bone, muscle, etc. all have fibrous structure. Fibre spinning and weaving technologies are available in nature since time immemorial. Nature has also demonstrated sophisticated technologies useful in the development of technical textiles like functional surfaces, camouflage, structural colour, thermal insulation, dry-adhesion, etc. Thus, biomimicry can be an inspiration to develop innovative textiles. This article reviews some of the important technologies of nature relating to textiles.

Encapsulated Silicene: A Robust Large-Gap Topological Insulator.

The quantum spin Hall (QSH) effect predicted in silicene has raised exciting prospects of new device applications compatible with current microelectronic technology. Efforts to explore this novel phenomenon, however, have been impeded by fundamental challenges imposed by silicene's small topologically nontrivial band gap and fragile electronic properties susceptible to environmental degradation effects. Here we propose a strategy to circumvent these challenges by encapsulating silicene between transition-metal dichalcogenides (TMDCs) layers. First-principles calculations show that such encapsulated silicene exhibit a two-orders-of-magnitude enhancement in its nontrivial band gap, which is driven by the strong spin-orbit coupling effect in TMDCs via the proximity effect. Moreover, the cladding TMDCs layers also shield silicene from environmental gases that are detrimental to the QSH state in free-standing silicene. The encapsulated silicene represents a novel two-dimensional topological insulator with a robust nontrivial band gap suitable for room-temperature applications, which has significant implications for innovative QSH device design and fabrication.

Development of an Innovative Bituminized Jute Paving Fabric (BJPF) Along with its Commercial Field Trials for Potential Application in the Field of Geotechnical Construction with an Eye Towards Global Concern

In the last quarter of the twentieth century, a new class of materials, Geosynthetics, emerged prospectively leading significant innovation in the design of geotechnical and geoenvironmental systems. Geotextiles have proven to be among the most versatile and techno-economically viable ground modification materials playing a significant role in modern pavement design and maintenance techniques. With the growing environmental concern across the globe, technologists, researchers have inclined towards the natural geotextile where Jute Geotextile (JGT) is one of the potential candidates. But, JGT has been restricted mainly as underlay in road construction. Hence, there is an urgent need to design and develop a precise innovative fabric as overlay on existing pavements and other emerging civil works to stay technically and economically competitive in the global market. Such a fabric will not only prove techno-economically viable but will also reduce the carbon foot-print generation to a large extent. This paper delineates the development of Grey Jute Paving Fabric (GJPF) followed by its bituminization with suitable type and grade of bitumen to develop Bituminized Jute Paving Fabric (BJPF). The BJPF will enhance the life of the overlay thereby reducing the cost of maintenance as well as serving as a partial substitute of bitumen mastic.

Crack-Photolithography for Membrane-Free Diffusion-Based Micro/Nanofluidic Devices.

Recent advances in controlling the cracking phenomena established a novel unconventional fabrication technique to generate mixed-scale patterns/structures with resolution and accuracy comparable to conventional nanofabrication techniques. Here, we adapt our previous cracking-assisted nanofabrication technique (called "crack-photolithography") relying on only the standard photolithography to develop micro/nanofluidic devices with greatly reduced time and cost. The crack-photolithography makes it possible not only to simultaneously produce micropatterns and nanopatterns with various dimensions but also to replicate both of the mixed-scale patterns in a high-throughput manner. Therefore, a microfluidic channel network can easily be fabricated with a nanochannel array that can function as a nanoporous membrane wherever necessary, which basically plays a key role in diffusion-allowed but convection-suppressed microfluidic devices. In addition, the nanochannel array can manipulate the transport of small molecules by adjusting its dimension and/or number at will, so that nanochannel-array-integrated micro/nanofluidic devices prove even more robust and accurate in diffusion control than conventional membrane-integrated microfluidic devices. As an application of such micro/nanofluidic devices, we employed synthetic bacterial cells and found that their genetic induction and expression are dominated by extracellular diffusive microenvironments that were completely engineered using the nanochannel array. Hence, the crack-photolithography could provide innovative fabrication techniques for unprecedented micro/nanofluidic devices that show substantial potential for a wide range of biological and chemical applications.

Innovative Fabrication of Wafer-Level InGaN-Based Thin-Film Flip-Chip Light-Emitting Diodes

In this letter, an innovative fabrication method for InGaN-based light-emitting diode (LED) was proposed, and the produced optical device was called the wafer-level InGaN-based thin-film flip-chip LEDs (wTFFC-LEDs). Packaging technologies, such as wafer-to-wafer bonding, laser lift-off, textured surface, and interconnection techniques, were applied to complete the device. Through this architecture, the absorption caused by electrodes in traditional vertical injection LEDs (V-LEDs) can be minimized, as well as the light extraction efficiency can be improved. Light-output power of wTFFC-LEDs (350 mA) was increased by 36.5% and 17.2% compared with the V-LEDs and flip-chip LEDs. Furthermore, the external quantum efficiency was also relatively enhanced by 36.3% and 15.5% higher than those of reference devices.

The sustainable future of the Scottish textiles sector: challenges and opportunities of introducing a circular economy model

Zero Waste Scotland introduced the concept of the circular economy to the Scottish textiles sector at events throughout 2013 to 2014. In April 2014, it commissioned research by independent consultants to examine the academic and industrial textile landscapes in Scotland, including developments in technical textiles and research into innovation in textile design and examples of circular economy models. The research identified a number of initiatives, including projects producing an alternative to denim and one developing cavity wall insulation from processed natural fibres. It made recommendations to Zero Waste Scotland about shaping the future landscape of textile innovation in Scotland and also offered examples of the circular economy from Scandinavia that might be applicable. The implementation of the circular economy into Scotland’s textile sector, underpinned by the aforementioned initiatives, can learn too from its textile and fibre heritage. Zero Waste Scotland is implementing an action plan which will offer support to the textile industry exploring ‘closed loop’ manufacturing, as well as funds for fashion designers to explore concepts such as zero-waste pattern design, luxury apparel from alternative textiles such as recycled polyethylene terephthalate and natural fibres such as nettle. A master class skills programme, delivered by leading UK and international experts, will bring together industry, academia, and higher education professionals to engage in learning and information exchanges about the circular economy. This paper presents Zero Waste Scotland’s role and the research findings.

Research Progress in Preparation of Porous Ceramics

Porous ceramics have been extensively studied during the last two decades because of their potential application in the fields of thermal insulators, gas filters, catalytic supports, separation membranes, kiln furniture, and biomedical substitutes for bone and teeth. The properties of porous ceramics are highly dependent on their method of preparation. This mini-review summarizes recent developments in innovative fabrication of porous ceramics such as three-dimensional printing, molten salt synthesis, and the sacrificial template and replica methods. Finally, we conclude with our personal perspectives and recommendations for future research in porous ceramics.

One-step fabrication of SERS-active substrates based on plasmon-induced activated water, with improved activity and excellent reproducibility

Generally, aggregation of Ag or Au nanoparticles (NPs) has emerged as a promising strategy to produce large enhancement of surface-enhanced Raman scattering (SERS). However, reproducibility of the SERS signal may be poor due to the unavoidable random field distribution. Maintaining both a high SERS effect and satisfactory reproducibility in the fabrication of ordered arrays of SERS-active substrates is most commonly adopted, but the corresponding procedures are quite complicated. In this work, we report on an innovative and facile one-step fabrication of SERS-active Au and Ag substrates with improved SERS activity and excellent signal reproducibility using simple oxidation–reduction cycles (ORCs) in 0.1N KCl. With this new strategy, hot electron transfer-induced activated (HETIA) water is utilized instead of conventional deionized (DI) water. Experimental results indicated that the corresponding SERS effect of the Au or Ag substrate prepared in HETIA-based solutions was higher than that prepared in DI water-based solutions. The SERS-active Au and Ag substrates prepared in AuNT water-based solutions demonstrated large respective enhancement factors (EFs) of 8.5×107 and 6.2×108. More importantly, the excellent reproducibility of the signal intensity of rhodamine 6G (R6G) was observed on both SERS-active Au and Ag substrates prepared in HETIA water-based solutions. When measuring solid samples, the corresponding relative standard deviations (RSDs) were 6% and 17% for the Au and Ag substrates, respectively. When measuring liquid samples, the corresponding RSDs were significantly reduced to ca. 1.6% and 8.1% for the two batches of experiments. These low RSDs, which are comparable to and even better than those shown in the literature, reported for this simple but innovative strategy ensure its reliable application in SERS-related studies.

Improved self-assembled thiol stationary phases in microfluidic gas separation columns

Semipacked columns (SPCs) with integrated micropillars have been characterized for high chromatographic efficiencies and fast separations. In this article, high-yield and stable alkane thiol based stationary phase coating methods are presented for SPCs. Briefly, a new three step (anisotropic, O2 plasma, and isotropic) etching method is first developed in order to improve metal lift-off by producing a 3-dimensional undercutting profile inside deep etched SPCs. This innovative fabrication scheme is used for 1m-long, 220μm-deep, 190μm-wide SPCs with circular micropillars of 20μm-diameters and 42μm-post spacing. Two different thin gold film deposition techniques are utilized for microcolumns (1) a wafer-level physical vapor deposition, and (2) a device level layer-by-layer (LbL) self-assembly of gold nanoparticles (3.2nm diameter). After gold film deposition and metal lift-off, the surface of the patterned gold layer is functionalized with a 2mM octadecanethiol (C18H37SH) solution for chromatographic separations. Both kinetic (Golay plots) and thermodynamic (Van’t Hoff plot) properties of thiol-functionalized gold phases are studied. The significance of SPCs, for faster analysis, is also validated by achieving baseline separation of a straight chain alkane mixture, containing high boilers (174°C to 287°C), within 45s.

Beef muscle isolation has no detrimental effect on premium ground beef programs

This experiment evaluated whether isolating certain muscles from the chuck for retail sale and excluding them from ground beef mix changes the number of days that ground chuck is acceptable to consumers. Chucks were harvested from twenty-four beef steers, and were allocated to either traditional or innovative fabrication methods. Resulting ground beef patties were stored in retail simulation conditions for 7days to determine color and oxidative stability. Raw patties were analyzed for thiobarbituric acid reactive substances (TBARS), oxymyoglobin concentration, objective color by Minolta Chromameter, and by a trained sensory panel for odor, color and percent discoloration. No differences (P>0.05) were observed between traditional and innovative style patties for TBARS, sensory odor or color, or oxymyoglobin concentration. Minolta Chromameter readings revealed more substantial fading (P<0.05) in traditional patties compared with innovative style patties. This study demonstrated that removing certain muscles from the ground chuck mix does not cause detrimental consequences in resulting ground chuck patties.

Superstrong, Chemically Stable, Superamphiphobic Fabrics from Particle‐Free Polymer Coatings

Superamphiphobic fabrics with a robust, chemically stable, highly liquid‐repellent surface have been prepared by one‐step coating treatment of fabric substrate using a coating solution comprising poly(vinylidene fluoride‐co‐hexafluoropropylene), fluoroalkyl silane, and a volatile solvent (e.g., acetone). The coated fabric has a contact angle of 162°, 156°, and 150° to water, olive oil, and silicone oil, respectively. The highly volatile solvent in the coating solution plays an important role in forming highly liquid repellent surface on the fabric. The coating is highly stable, and can withstand 98% concentrated sulfuric acid and strong alkaline solution (e.g., 40% KOH). It is also durable enough against at least 800 cycles of machine wash, and 10 000 cycles of abrasion. Physical damages such as abrasion with a fabric, rubbing with sandpaper, or scratching with a sharp blade can even increase the liquid repellency to a certain extent. In addition, the coating has a self‐healing property against UV damages. Such a superstrong, superamphiphobic fabric coating may find applications in development of innovative textiles and functional clothing for various applications.

Processing and Modification of Ionic Polymers Metal Composites (IPMC) - A Review

This paper presents an overview of various innovative fabrication approaches and the potential applications of ionic polymer metal composites (IPMC), which is a composite material consisting of a polymer membrane sandwiched between two thin electrode layers. When given a voltage within a range of 1-5V, cations inside accompanying with water molecules of IPMC move across the width of the material causing a uniform water distribution and finally to achieve it’s bending motion. In addition to a classical processing method, three innovative modification approaches are recommended to fabricate IPMC, particularly to settle water electrolysis and leakage for multiple practical applications. Also, three applications are extensively highlighted in the later pages of the paper. This is a very new field and with the research done so far, it is believed that IPMC has a potential which is worth research elaborately. This paper presents an overview of the manufacturing components, techniques, related problems and applications of IPMC. Additionally, it recommends innovative modification fabrication approaches to subdue the associated problems in the existing conventional fabrication processing.

E-textiles in Clinical Rehabilitation: A Scoping Review

Electronic textiles have potential for many practical uses in clinical rehabilitation. This scoping review appraises recent and emerging developments of textile-based sensors with applications to rehabilitation. Contributions published from 2009 to 2013 are appraised with a specific focus on the measured physiological or biomechanical phenomenon, current measurement practices, textile innovations, and their merits and limitations. While fabric-based signal quality and sensor integration have advanced considerably, overall system integration (including circuitry and power) has not been fully realized. Validation against clinical gold standards is inconsistent at best, and feasibility with clinical populations remains to be demonstrated. The overwhelming focus of research and development has been on remote sensing but the opportunity for textile-mediated feedback to the wearer remains unexplored. Recommendations for future research are provided.

Development and functional evaluation of biomimetic silicone surfaces with hierarchical micro/nano-topographical features demonstrates favourable in vitro foreign body response of breast-derived fibroblasts

Reproducing extracellular matrix topographical cues, such as those present within acellular dermal matrix (ADM), in synthetic implant surfaces, may augment cellular responses, independent of surface chemistry. This could lead to enhanced implant integration and performance while reducing complications. In this work, the hierarchical micro and nanoscale features of ADM were accurately and reproducibly replicated in polydimethylsiloxane (PDMS), using an innovative maskless 3D grayscale fabrication process not previously reported. Human breast derived fibroblasts (n = 5) were cultured on PDMS surfaces and compared to commercially available smooth and textured silicone implant surfaces, for up to one week. Cell attachment, proliferation and cytotoxicity, in addition to immunofluorescence staining, SEM imaging, qRT-PCR and cytokine array were performed. ADM PDMS surfaces promoted cell adhesion, proliferation and survival (p=<0.05), in addition to increased focal contact formation and spread fibroblast morphology when compared to commercially available implant surfaces. PCNA, vinculin and collagen 1 were up-regulated in fibroblasts on biomimetic surfaces while IL8, TNFα, TGFβ1 and HSP60 were down-regulated (p=<0.05). A reduced inflammatory cytokine response was also observed (p=<0.05). This study represents a novel approach to the development of functionalised biomimetic prosthetic implant surfaces which were demonstrated to significantly attenuate the acute in vitro foreign body reaction to silicone.

A multifaceted aggregation and toxicity assessment study of sol–gel-based TiO2 nanoparticles during textile wastewater treatment

Innovative textiles have been concern of emerging risk of nanoparticles (NPs) to human and environment. This study aimed to investigate the aggregation, removal and biological, and ecotoxicological effects of sol–gel-based TiO2 NPs while the treatment of textile wastewater. Fe(II) and alum coagulants were applied for the removal of spiked TiO2 NPs from textile wastewater. Particle size distribution, absorbance values (UV–vis range), and residual TiO2 NPs were followed to define aggregation mechanism, including pH variation during treatment of wastewater. The effect of TiO2 on activated sludge treatment was followed by monitoring of oxygen uptake rate (OUR). Ecotoxicity of sol–gel and coagulated samples was observed by Ceriodaphnia magna immobilization test. Adjustment of pH to 8 enlarged mean particle size distribution of sol–gel-based TiO2 NPs from 30 to 450 nm. After alum and Fe(II) coagulations, average particle size distributions were observed to be 650 and 960 nm, respectively. Coagulation with alum and Fe(II) resulted over >95% removal of TiO2 from biologically treated textile wastewater (BTTWW). The value for residual TiO2 concentration in BTTWW was reduced from 120 μg/L to around 8 μg/L TiO2 NPs exhibited slight/no toxicity on the OUR while toxicity to Ceriodaphnia dubia increased in some coagulated samples, most probably due to higher residual coagulant concentrations.

Novel self-assembly-induced 3D plotting for macro/nano-porous collagen scaffolds comprised of nanofibrous collagen filaments

This study proposes self-assembly-induced 3D plotting as an innovative solid freeform fabrication (SFF) technique for the production of macro/nano-porous collagen scaffolds, particularly comprised of nanofibrous collagen filaments. In this technique, collagen filaments deposited in a coagulation bath could be effectively gelled through the self-assembly of collagen molecules into fibrils, accordingly, enabling the 3-dimensional deposition of collagen filaments with a collagen nanofiber network. The unique macro/nano-structure could be structurally stabilized by dehydration process coupled with chemical cross-linking. The porous collagen scaffolds produced had 3-dimensionally interconnected macropores (~ 451×305μm in pore width) separated by nanoprous collagen filaments. In addition, the macro/nano-porous collagen scaffolds showed the tensile strength of~353kPa and compressive strength of~31kPa at a porosity of~95vol% and excellent in vitro biocompatibility, assessed using pre-osteoblast MC3T3-E1 cells.

Polyvinylamine modified polyester fibers – innovative textiles for the removal of chromate from contaminated groundwater

A new polyelectrolyte and textile based adsorbent material for the removal of chromate from contaminated groundwater.

Thermal and mechanical behavior of innovative melt-blown fabrics based on polyamide nanocomposites

A commercial organo-modified clay (OMC) was added to a polyamide 6 (PA6) matrix at various concentrations during the polymerization stage or by melt compounding in a twin-screw extruder, and the resulting pellets were used for the production of depth filters in the shape of cylindrical nonwoven webs through a melt-blown process. The processability of the investigated materials was significantly affected by nanofiller introduction. Differential scanning calorimetry revealed that OMCs play a nucleating effect on the crystallization of the polyamide matrix, with a remarkable increase in the crystallization temperature on cooling from the melt. Consequently, a parameter related to the filtering performances of the web, such as the pressure drop (Δ P) evaluated on cylindrical filters, decreased with the increase in die-to-collector distance in a more pronounced way for nanocomposite nonwovens. This behavior was related to the significant decrease of the connecting points in the networks due to the rapid cooling of the filaments on the collecting mandrel. Compressive mechanical tests evidenced how organoclay addition led to a remarkable increase of the rigidity of the web, when the data were compared at the same Δ P value, irrespectively from the preparation technique.