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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 extend existing knowledge of 4D printing, in line with Khoo et al. (2015) who defined the production of 4D printing using a single material, and 4D printing of multiple materials. It is proposed that 4D printing can be achieved through the use of functionally graded materials (FGMs) that involve gradational mixing of materials and are produced using an additive manufacturing (AM) technique to achieve a single component.

The latest state-of-the-art literature was extensively reviewed, covering aspects of materials, processes, computer-aided design (CAD), applications and made recommendations for future work.

This paper clarifies that functionally graded additive manufacturing (FGAM) is defined as a single AM process that includes the gradational mixing of materials to fabricate freeform geometries with variable properties within one component. The paper also covers aspects of materials, processes, CAD, applications and makes recommendations for future work.

This paper examines the relationship between FGAM and 4D printing and defines FGAM as a single AM process involving gradational mixing of materials to fabricate freeform geometries with variable properties within one component. FGAM requires better computational tools for modelling, simulation and fabrication because current CAD systems are incapable of supporting the FGAM workflow.

It is also identified that other factors, such as strength, type of materials, etc., must be taken into account when selecting an appropriate process for FGAM. More research needs to be conducted on improving the performance of FGAM processes through extensive characterisation of FGMs to generate a comprehensive database and to develop a predictive model for proper process control. It is expected that future work will focus on both material characterisation as well as seamless FGAM control processes.

This paper examines the relationship between FGAM and 4D printing and defines FGAM as a single AM process that includes gradational mixing of materials to fabricate freeform geometries with variable properties within one component.

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.

This paper aims to explore and demonstrate the ability to integrate entry-level additive manufacturing (AM) techniques with responsive polymers capable of mechanical to chemical energy transduction. This integration signifies the merger of AM and smart materials.

Custom filaments were synthesized comprising covalently incorporated spiropyran moieties. The mechanical activation and chemical response of the spiropyran-containing filaments were demonstrated in materials that were produced via fused filament fabrication techniques.

Custom filaments were successfully produced and printed with complete preservation of the mechanochemical reactivity of the spiropyran units. These smart materials were demonstrated in two key constructs: a center-cracked test specimen and a mechanochromic force sensor. The mechanochromic nature of the filament enables (semi)quantitative assessment of peak loads based on color change, without requiring any external analytical techniques.

This paper describes the first examples of three-dimensional-printed mechanophores, which may be of significant interest to the AM community. The ability to control the chemical response to external mechanical forces, in combination with AM to process the bulk materials, potentiates customizability at the molecular and macroscopic length scales.

Additive manufacturing has rapidly developed in terms of technology and its application in various types of industries. With this rapid development, there has been significant research in the area of materials. This has led to the invention of Smart Materials (SMs). The 4D printing is basically 3D printing of these SMs. This paper aims to focus on novel materials and their useful application in various industries using the technology of 4D printing.

Research studies in 4D printing have increased since the time when this idea was first introduced in the year 2013. The present research study will deeply focus on the introduction to 4D printing, types of SMs and its application based on the various types of stimulus. The application of each type of SM has been explained along with its functioning with respect to the stimulus.

SMs have multiple functional applications pertaining to appropriate industries. The 4D printed parts have a distinctive capability to change its shape and self-assembly to carry out a specific function according to the requirement. Afterward, the fabricated part can recover to its 3D printed “memorized” shape once it is triggered by the stimulus.

The present study highlights the various capabilities of SMs, which is used as a raw material in 4D printing.

The purpose of this article is to reviews state-of-the-art developments in four-dimensional (4D) printing, discuss what it is, investigate new applications that have been discovered and suggest its future impact.

The article clarifies the definition of 4D printing and describes notable examples covering material science, equipment and applications.

This article highlights an emerging technology cycle where 4D printing research has gained traction within additive manufacturing. The use of stimuli-responsive materials can be programmed and printed to enable pre-determined reactions when subject to external stimuli.

This article reviews state-of-the-art developments in 4D printing, discusses what it is, investigates new applications that have been discovered and suggests its future impact.

Shape memory polymers (SMPs) respond with a change in their shape against a specific stimulus by memorizing their original shape and are reformed after deformation most often by changing the temperature of the surrounding without additional mechanical efforts. In the coming years, these polymers indeed will be in limelight to manufacture textile materials which will retain their shape even after prolonged use under disturbed conditions. This study aims at defining shape memory materials and polymers as well as their technological characteristics and also highlights application in various fields of textiles.

The methodology used to explain these SMPs have been carried out starting with the discussion on their properties, their physical nature, types, viz., shape memory alloys (SMAs), shape memory ceramics, shape memory hybrid, magnetic shape memory alloy, shape memory composites, shape memory gels and SMP along with properties of each type. Other related details of these polymers, such as their advantages, structure and mechanism, shape memory functionality, thermally responsive SMPs and applications, have been detailed.

It has been observed that the SMPs are very important in the fields of wet and melt-spun fibers to offer novel and functional properties, cotton and wool fabric finishing, to produce SMP films, foams and laminated textiles, water vapor permeable and breathable SMP films, etc.

The field of SMPs is new, and very limited information is available to enable their smooth production and handling.

The paper aims to promote the development of intelligent materials and the 4D printing technology by introducing recent advances and applications of additive layered manufacturing (ALM) technology of intelligent materials and the development of the 4D printing technology. Also, an arm-type ALM technology of shape memory polymer (SMP) with thermosetting polyurethane is briefly introduced.

This paper begins with an overview of the development and applications of intelligent materials around the world and the 4D printing technology. Then, the authors provide a brief outline of their research on arm-type ALM technology of SMP with thermosetting polyurethane.

The paper provides the recent developments and applications of intelligent materials and 4D printing technology. Then, it is suggested that intelligent materials mixed with different functional materials will be developed, and these types of materials will be more suitable for 4D printing.

This paper overviews the current developments and applications of intelligent materials and its use in 4D printing technology, and briefly states the authors’ research on arm-type ALM technology of SMP with thermosetting polyurethane.

The purpose of this paper is to examine the dynamics of self-regulatory focus (SRF) in the context of advertising effectiveness pertaining to rational vs emotional appeals. Past research has dichotomized self-regulatory (SR) foci (i.e. prevention or promotion) on the basis of an individual’s so-called “chronic” orientation, i.e. high or low prevention focus; high or low promotion focus. However, psychological theorists purport that SRF is orthogonal and, thus, various combinations of both foci are evident in any given population.

A two (rational appeal vs emotional appeal)×two (utilitarian product vs hedonic product) experimental design was used. Data was collected via an online survey instrument which included the stimulus advertisements (experimental manipulations) and the relevant independent (SRF) and dependent measures (advertising effectiveness).

The findings of this study support application of regulatory focus theory (RFT) as an appropriate framework to study consumer behaviour and as a mechanism by which to segment consumers. However, past advertising research has predominantly examined consumer’s “chronic” foci (i.e. prevention and promotion). This study found that consumers can adopt various combinations of information processing styles and goal orientations and cannot be boxed into dichotomous categories based on either a prevention of promotion focus. As such, the findings reveal very different conclusions in contrast to previous advertising and marketing research in the SRF area.

This study is the first to approach SRF from a quadratic perspective (i.e. involving all SRF combinations). In calling to question the validity of previous findings, this study paves the way for numerous future research opportunities.