Smart Textile‐Based Personal Thermal Comfort Systems: Current Status and Potential Solutions

Nanocomposites with polymer matrix offer excellent opportunities to explore new functionalities beyond those of conventional materials. TiO2, as a reinforcement agent in polymeric nanocomposites, is a viable strategy that significantly enhanced their mechanical properties. The size of the filler plays an essential role in determining the mechanical properties of the nanocomposite. A defining feature of polymer nanocomposites is that the small size of the fillers leads to an increase in the interfacial area compared to traditional composites. The interfacial area generates a significant volume fraction of interfacial polymer, with properties different from the bulk polymer even at low loadings of the nanofiller. This review aims to provide specific guidelines on the correlations between the structures of TiO2 nanocomposites with polymeric matrix and their mechanical properties. The correlations will be established and explained based on interfaces realized between the polymer matrix and inorganic filler. The paper focuses on the influence of the composition parameters (type of polymeric matrix, TiO2 filler with surface modified/unmodified, additives) and technological parameters (processing methods, temperature, time, pressure) on the mechanical strength of TiO2 nanocomposites with the polymeric matrix.

Synergic Effect of TiO2 Filler on the Mechanical Properties of Polymer Nanocomposites.

Compression therapy with stockings or bandages is the most common treatment for venous or lymphatic disorders. The objective of this study was to investigate the influence of bandage mechanical properties, application technique and subject morphology on the interface pressure, which is the key of this treatment. Bandage stretch and interface pressure measurements (between the bandage and the leg) were performed on 30 healthy subjects (15 men and 15 women) at two different heights on the lower leg and in two positions (supine and standing). Two bandages were applied with two application techniques by a single operator. The statistical analysis of the results revealed: no significant difference in pressure between men and women, except for the pressure variation between supine and standing positions; a very strong correlation between pressure and bandage mechanical properties (p < 0.00001) and between pressure and bandage overlapping (p < 0.00001); a significant pressure increase from supine to standing positions (p < 0.0001). Also, it showed that pressure tended to decrease when leg circumference increased. Overall, pressure applied by elastic compression bandages varies with subject morphology, bandage mechanical properties and application technique. A better knowledge of the impact of these parameters on the applied pressure may lead to a more effective treatment.

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Experimental Investigation of Pressure Applied on the Lower Leg by Elastic Compression Bandage

In this work, a novel type of biodegradable hybrids consisting of titanium dioxide (TiO2) and chitosan has been fabricated. At first, the TiO2 nanoparticles were modified with N-trimellitylimido-S-valine diacid to express biomateral moieties through available amino acid groups. The microscopy results demonstrated that the modified TiO2 nanoparticles were dispersed homogeneously in the chitosan matrix at the nanometric scale, which could be assigned to covalent bonds as well as hydrogen bonding formed between chitosan and TiO2-diacid. Among all of the prepared films, a nanocomposite film containing 15 wt.% TiO2 exhibited the highest thermal and mechanical performance.

Effect of Functionalized TiO2 on Mechanical, Thermal and Swelling Properties of Chitosan-Based Nanocomposite Films

This review explores research and development in wool metrology to date. In doing so, it highlights the research work undertaken by three organisations, in particular, to the development of wool and textile metrology research covering all of the important physical properties of wool. Three key wool research centres at the beginning of the twenty-first century were CSIRO's Division of Textile and Fibre Technology at Belmont near Geelong, Victoria, the School of Fibre Science and Technology, University of NSW at Kensington, NSW in Australia, and the Wool Research Organisation of New Zealand Inc. at Lincoln near Christchurch, New Zealand. Due to funding pressures between 1997 and 2007, these centres either ceased to operate or were absorbed into larger, non-wool-focused organisations. The substantial contribution to the world's wool metrology literature made by their staff and graduates, over the period when the three organisations had around 300–500 staff involved in wool-related research activities, is rec...

Wool metrology research and development to date

Nano materials are manufactured through different techniques. The small length scales present in nanoscale systems directly influence the energy band structure and can lead indirectly to changes in the associated atomic structure termed as quantum confinement. Conventional polymer composites usually reinforced by micrometerscale fillers into polymer matrices involve compromises in properties. Nanoscale filled polymer composites or polymer nanocomposites gave a new way to overcome the limitations of traditional counterparts. Polymer nanocomposites are synthesised through different techniques depend on their nature. Stereoregular polypropylene is produced due to its industrial use. The properties of polypropylene-TiO2 nanocomposite material improved compared to polypropylene in terms of antibacterial, mechanical, UV protection, thermal and hydrophilicity properties.

A Review on Polymer Tio2 Nanocomposites

Flat polyester yarn is bulked by the mechanical crimp texturizing process. The magnitude of the false-twist, introduced together with the torsional rigidity of the supply yarn, has a significant effect on the transformation process. The torsional rigidity of the supply yarn is in turn influenced by its fineness and bending characteristics. It is therefore deemed necessary to establish a mathematical relationship between the optimum false-twist level and the yarn fineness for materials with known bending characteristics. Such a relationship may help in producing a yarn with optimum bulk properties, while minimizing resource utilization and waste generation. This paper reports research work done in this direction. Polyester yarn is chosen for this investigation as it has a wide range of applications. Fully drawn multifilament polyester yarns, with different linear densities, are textured on a single-head mechanical crimp texturing machine. The results are analysed with the help of polynomial curve fitting (Polyfit) using MATLAB. This mathematical tool facilitated the deri- vation of the desired formula (polynomial equation) for the calculation of optimum false-twist level for fully drawn multifilament polyester yarns undergoing mechanical crimp texturizing.

Deriving an empirical formula to determine the optimum level of false-twist in mechanically-crimped textured polyester yarn

Development of prototype bandage lapper for constant tension bandaging required for effective medical-clinical treatments.

There are technological limitations in the processing of smooth, slippery and rather flat multifilament viscose rayon yarn. The present work describes a shorter route for viscose rayon modification through mechanical crimp texturizing. Texturizing was performed with different pre-twists and optimized texturizing twist. This work describes a shorter and cost effective route for viscose rayon modification through mechanical crimp texturizing. The prepared texturized viscose rayon yarn has achieved the desirable structural characteristics of spun yarn as depicted in SEM micrographs. The textured yarn has retained an almost identical fineness with the parent yarn. Unlike air jet texturizing, mechanical crimp texturizing has benefits in terms of retro-processing of costlier viscose rayon yarn. Although it was textured, it has not shown any significant drop in tenacity and, apart from that, shows enhanced the elongation property compared to the parent yarn.

Mechanical crimp texturizing of non-thermoplastic viscose rayon yarn:

The present paper represents a brief review of life saving system in roll- over accidents, while driving on the road by a four wheeler. An Airbag is an automotive safety restraint system for an occupant as well as passengers. The system consists of a flexible fabric envelope or cushion, designed to inflate rapidly during an automobile collision. Its purpose is to cushion occupants during a crash and provide protection to their bodies when they strike interior objects such as the steering wheel or a window etc. Thus it lowers the number of injuries by reducing the force exerted by steering wheel, windows and the dashboard at any point on the body. Continuing research and developments are going on in its module design, combustible material, air bag fabric design and material, coating etc. in making this life saving safety device further efficient. However, success of any safety restraint device depends on its correct implementation and certain safety rules to be followed.

Tasnim N. Shaikh

Papers

A Review on Polymer Tio2 Nanocomposites

Deriving an empirical formula to determine the optimum level of false-twist in mechanically-crimped textured polyester yarn

Development of prototype bandage lapper for constant tension bandaging required for effective medical-clinical treatments.

Mechanical crimp texturizing of non-thermoplastic viscose rayon yarn:

Air Bag: A Safety Restraint System of an Automobile.