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In this study, fabrication of polymer and cotton fabric exhibiting stimuli-responsive wetting and water vapor permeability features together with antibacterial activity was aimed.

Temperature and pH-responsive poly(N-isopropyl acrylamide-graft-chitosan) (PNIPAM-g-CS) copolymer were produced via the free radical addition polymerization method and fixed to the cotton fabric using butane tetracarboxylic acid (BTCA) cross-linker by double-bath impregnation method. The chemical structure of the graft copolymer was characterized by Fourier-transform infrared spectroscopy (FT-IR) spectroscopy and H-Nuclear magnetic resonance (1H NMR) analyses. Thermo-responsive behavior of the fabric was investigated by wetting time and water uptake tests, contact angle measurement and surface energy calculation. Additionally, antibacterial activity of the fabric treated with copolymer was studied against S. aureus bacterium.

PNIPAM-g-CS graft copolymer was synthesized successfully, which had lower critical solution temperature (LCST) value of 32 °C and exhibited thermo-responsive property. The treated fabrics exhibited hydrophilic character at temperatures below the LCST and hydrophobic character at temperatures above the LCST. It was found that polymer-coated fabric could have regulated the water vapor permeability by the change in its pore size and hydrophilicity depending on the temperature. Additionally, treated fabric displayed a pH-responsive water absorption behavior and strong antibacterial activity against S.aureus bacterium.

In the study, it has been shown that the cotton fabrics can be fabricated which have antibacterial activity and capable of pH and temperature responsive smart moisture/water management by application of copolymer. It is thought that the fabric structures developed in the study will be promising in the production of medical textile structures where antibacterial activity and thermophysiological comfort are important.

The purpose of this paper is to prepare a dual-encapsulated halloysite nano-container to release the capsuled inhibitor as an additive for corrosion protection of epoxy coating.

Halloysite nano-containers (HNT) were prepared by simultaneously implanting inhibitor benzotriazole (BTA) into the inside and outside of the halloysite using reduced pressure and layer-by-layer (LBL) assembly, respectively. The microstructure and morphology of treated HNT were investigated using Fourier transform infrared spectroscopy and transmission electron microscopy. In addition, the anti-corrosion behaviors of the composite polyepoxy coating with inhibitor-loaded nano-containers BTA@HNT-2 were investigated using the electrochemical impedance spectroscopy and neutral salt spray test.

Test results showed that the LBL assembly structure of the halloysite nano-container makes the BTA@HNT-2 nano-container be controlled and sustained to release BTA, relying on the pH. Very importantly, the obtained nano-container is also responsive to temperature, owing to the thermosensitivity polyelectrolyte out-shell of the HNT. The result showed R_ct of the composite polyepoxy coating can be sufficient to maintain higher than 8.510E+7 Ω·cm² over 72 h of immersion test. Moreover, the artificial induced defects on the coating surface were sufficiently inhibited in the presence of BTA@HNT-2 nano-container in the polyepoxy coating.

Use of the BTA@HNT-2 as corrosion inhibitor nano-container, with good anti-corrosion property and dual-responsive to pH and temperature, offers a significant rout to prepare smart anti-corrosion coating for protecting metal substrate.

The fabrication and characterization of a hydrogel-based conductometric sensor have been carried out. The purpose of this research is to fabricate a small robust hydrogel-based conductometric sensor for real-time monitoring of pH in the physiological range.

A pH-responsive Chitosan/Gelatin composite hydrogel has been used for this purpose. This study reports and analyzes the sensing response obtained from four hydrogel compositions with varying Chitosan/Gelatin ratios. The pH-responsive nature of the hydrogel has been mapped out through volumetric and conductometric tests. An attempt has been made to correlate these characteristics with the physico-chemical nature of the hydrogel through scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction techniques.

The four hydrogel compositions differed on the basis of gel composition ratios; the conductometric analysis results prove that the sensor with the hydrogel composition (Chitosan 2 per cent, Gelatin 7 per cent, ratio 1:2) produces the best pH resolution in the pH range of 4 to 9. The sensing mechanisms and the differences obtained between individual sensor outputs have been discussed in detail. On the basis of this extensive in vitro assessment, it has been concluded that while key pendant functional groups contribute to pH-responsive characteristics of the hydrogel, the overall sensitivity of the sensors gel component to surrounding pH is also determined by the crystalline to amorphous ratio of the hydrogel composite, its interpenetrating cross-linked structure and the relative ratio of the hydrophilic to the pH-sensitive components.

The conductometric sensor results prove that the fabricated sensor with the shortlisted hydrogel composition shows good sensitivity in the physiological pH range (4 to 9) and it has the potential for use in point of care medical devices for diagnostic purposes.

This is the first reported version of the fabrication and testing and analysis/comparison of a hydrogel-based conductometric sensor based on this composition. The work is original and has not been replicated anywhere.

Real-time monitoring of wound or injured tissues is critical for speedy recovery, and the onset of a cascade of biochemical reactions provides potential biomarkers that facilitate the process of wound monitoring, e.g. pH, temperature, moisture level, bacterial load, cytokines, interleukins, etc. Among all the biomarkers, pH has been known to have a profound impact on the wound healing process, and is used to determine the incidence of bacterial infection of the wound (persistently elevated alkaline pH), proteolytic activity at the site of injury, take rate in skin grafting, wound healing stage and preparation for wound debridement.

This review highlights the significance of pH in determination of clinical parameters and for selection of an appropriate treatment regime, and it presents an in-depth analysis of the designs and fabrication methods that use integrated pH sensors, which have been reported to date for the real-time monitoring of wound healing.

For an expedited wound healing process, the significance of pH mandated the need of an integrated sensor system that would facilitate real-time monitoring of healing wounds and obviate the requirement of redressing or complicated testing procedures, which are both labor-intensive and painful for the patient. The review also discussed different types of sensor systems which were developed using hydrogel as a pH-responsive system coupled with voltammetry, potentiometry, impedimetric and flex-circuit inductive transducer systems. All of the mentioned devices have considerable potential for clinical applications, and there is need of in vivo testing to validate their efficiency and sensitivity under practical scenarios.

This manuscript is an original review of literature, and permission has been granted to use the figures from previously published papers.

The purpose of this paper is to examine the underlying mechanism and physico‐chemical requirements of chemo‐responsive shape change/memory polymers and to explore the future trend of development and potential applications.

Working mechanism in chemo‐responsive shape change/memory polymers is firstly identified. And then the physico‐chemical requirements for the representative polymers are characterized.

The different working mechanisms, fundamentals, physico‐chemical requirements and theoretical origins have been discussed. Current research and development on the fabrication strategies of chemo‐responsive shape change/memory polymers have been summarised. The future trend and potential applications have been explored and estimated.

This review examines physico‐chemical requirements and theoretical origins necessary to achieve chemo‐responsiveness, and then discusses recent developments and future trends.

Shape change/memory polymers can be used in the broad field of bio‐ and/or medicine.

Breakthroughs and rapid development of chemo‐responsive shape change/memory polymers will significantly improve the research and development of smart materials, structures and systems.

Polymeric fibres that have a unique capability to change their structure in response to small environmental changes such as pH, electrolyte and electric field are an attractive alternative for artificial muscles. Stimuli sensitive fibres were prepared by the modification of commercial polyacrylonitrile (PAN) fibres. The modification was carried out in two steps: thermo-oxidation and hydrolysis. During the thermo-oxidation step, the crosslinks imparted through the pendant nitrile groups provided a stable structure. While in the subsequent saponification step, the uncrosslinked nitrile groups were converted to responsive carboxylic acid groups. The effect of stabilization parameters and saponification conditions on the structure, properties and swelling behaviour of these fibres was investigated. The fibres showed muscle like expanding and contracting behaviour stimulated by changes in pH of the environment.

The purpose of this paper is to use the bio-based resource as the starting material for the synthesis of azo dye. Cardanol is one of the most used bio-based resources for carrying out the synthesis of various compounds having numerous end applications. The study presents an attempt to develop an azo dye from Cardanol having end applications in pH-responsive dyes.

The cardanol was sulfonated to block the para position by which ortho positioned hydroxyl group after diazotization and coupling will provide necessary pH-sensitivity. The diazotization of two naphthalene derivatives, i.e. 1-naphthol-8-amino-3,6-disulfonic acid (H-acid) and 7-amino-4-hydroxy-2-naphthalene sulfonic acid (J-acid) was carried out using the standard practice, and the diazotized compounds were coupled with the sulfonated cardanol. The obtained dyes were characterized by Fourier transform infrared, nuclear magnetic resonance, carbon-hydrogen-nitrogen-sulfur analysis and hydroxyl value. The colour properties were checked using UV-vis spectrophotometry and density functional theory, while thermogravimetric analysis was used for the thermal degradation studies of both the dyes.

Water-soluble cardanol-based azo dyes were prepared successfully having good thermal stability, and the obtained results are being presented in this paper.

The originality lies between the use of cardanol as a bio-based resource for the synthesis of azo-dye and the obtained azo-dye has the pH-sensitivity.

The paper aims to provide an overview of the area of smart textiles.

The paper describes and discusses new and developing materials and technologies used in the textile industries.

Significant progress has been achieved in the area of technical textiles. Fibres, yarns, fabrics and other structures with added‐value functionality have been successfully developed for technical and/or high performance end‐uses. The basic building blocks are already in place in the field of smart textiles and clothing.

As progress in science and engineering research advances, and as the gap between designers and scientists narrows, the area of smart clothing is likely to keep on expanding for the foreseeable future. Growth is predicted to occur in two distinct directions: performance‐driven smart clothing and fashion‐driven smart clothing. There are challenges that have to be addressed.

The paper provides information of value to those interested in the future directions of the textile industry.

A novel grafted temperature-responsive ReO₄⁻ Imprinted composite membranes (Re-ICMs) was successfully prepared by using polyvinylidene fluoride (PVDF) resin membranes as substrates, this study aimed to separate and purify ReO effectively.

Re-ICMs were synthesized by PVDF resin membranes as the substrate, acrylic acid (AA), acrylamide (AM), ethylene glycol dimethacrylate (EGDMA) were functional monomers. The morphology and structure of Re-ICMs were characterized by scanning electron microscope and Fourier transform infrared spectroscopy.

The maximum adsorption capacity toward ReO₄⁻ was 0.1,163 mmol/g and the separation decree had relation to MnO₄⁻ was 19.3. The optimal operation conditions were studied detailedly and the results as follows: the molar ratios of AA, AM, EGDMA, ascorbic acid, NH4ReO₄, were 0.8, 0.96, 0.02, 0.003 and 0.006. The optimal time and temperature were 20 h and 40°C, respectively. The Langmuir and pseudo-second-order models were fit these adsorption characteristics well.

Rhenium (Re) is mainly used to chemical petroleum and make superalloys for jet engine parts. This study was representing a technology in separate and purify of Re, which provided a method for the development of the petroleum and aviation industry.

This contribution provided a novel method to separate ReO₄⁻ from MnO₄⁻. The maximum adsorption capacity was 0.1163 mmol/g at 35°C and the adsorption equilibrium time was within 2 h. Meanwhile, the adsorption selectivity rate ReO₄⁻/MnO₄⁻ was 19.3 and the desorption rate was 78.3%. Controlling the adsorption experiment at 35°C and desorption experiment at 25°C in aqueous solution, it could remain 61.3% of the initial adsorption capacity with the adsorption selectivity rate of 13.3 by 10 adsorption/desorption cycles, a slight decrease, varied from 78.3% to 65.3%, in desorption rate was observed.

This paper describes the development, implementation, and preliminary outcomes of Enhancing Departments and Graduate Education (EDGE) in Geography, a multiyear project begun in 2005 to study the process of professional development in graduate geography in the U.S and sponsored by the National Science Foundation. As a research and action project responding to the needs of graduate geography programs, EDGE seeks to provide academic geographers with an empirical perspective of disciplinary as well as interdisciplinary and generic skills that M.A./M.S. and Ph.D. students develop as a result of graduate education. Related objectives are to understand how disciplinary skills are applied by geography graduates once they enter the professional workforce in both academic and nonacademic professional settings, and to gauge the extent graduate programs are sufficiently preparing geography graduates for those careers. We begin by summarizing the research goals and design of EDGE, highlighting the roles and contributions of geographers and educational researchers, and noting the interplay and synergy between disciplinary and interdisciplinary methodologies and practices. To date, research has focused on: (1) assessing contemporary workforce competencies in professional geography and (2) examining the role of department climate and culture on student experience and faculty development within masters and doctoral programs. Although the EDGE research efforts are still underway, we present some preliminary research findings and discuss the implications of those outcomes for professional development in geography and related social and environmental sciences. Also discussed is the complementary nature of disciplinebased and interdisciplinary professional development efforts.