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The textile polymeric composites define a class of advanced materials, utilising fabrics as reinforcement. The geometry, as well as the structure of textile reinforced polymeric composites, are much more complex than that of composites reinforced with unidirectional fibres. The mechanical properties of textile reinforced composites are influenced by several parameters such as fibre material, the internal geometry of the fabric, number of counts, size of gap between adjacent yarns, height of woven layer, undulation and thickness of the composite lamina. Each of these factors can influence the structural behaviour and can be modelled based on its specific length scale. This paper is focused on the modelling procedures of the in-plane stiffness characteristics, specific to satin reinforced laminated composites. The method used is a compromise between the continuous and pure discrete approaches and it is associated with a mesoscopic analysis of the repetitive unit cell (RUC). The elastic properties of the textile reinforced polyester composite, using S glass fibre, arranged in satin reinforcement, are determined and analysed taking into account the variation of two characteristic geometric parameters, namely the width and the height of the reinforcing tow.

This paper reports the fabrication of spherical particles developed as bone tissue regenerative biomaterials. Inspired by the extracellular matrix of hard tissues, the particles were generated through the mineral loading of a macromolecular matrix consisting in a bicomponent hydrogel (interpenetrated polymer networks based on gelatin and alginate). The study describes the effects of the peptide-polysaccharide ratio on the morpho-structural features, water affinity, and interaction with MG-63 osteoblast-like cells.

The management of laryngeal trauma represents one of the most challenging problems for an ENT surgeon. The alternatives vary from a “wait and see” approach to extensive and immediate reconstructive interventions, but in all cases the risk of laryngeal stenosis remains high. This translates into a poor quality of life for the patients and increased costs for the health system. The use of a resorbable plate for the reconstruction of the affected cricoid has the advantages of requiring a single intervention and enabling the patient to return to his normal activities in a shorter period of time. It is why we present this method of approach, which can be a viable alternative in managing these difficult cases.

The aim of this study was to point out the effect of elaboration parameters on the structure and electrochemical stability of a bioinspired hybrid film chitosan with hydroxiapatite (HAp) on Ti50%Zr alloy. The new hybrid films based on chitosan and hydroxiapatite were elaborated electrochemically using various ratio between components and different temperature and time of electrodeposition. The electrodeposition electrolye was a mixture of (NH4)2HPO4 , Ca(NO3)2 and chitosan. The structure was identified by Fourier transform infrared (FTIR) spectroscopy, and the morphology associated with elemental analysis were evaluated by scanning electronic microscopy (SEM) and X ray diffraction. Surface characterization was completed with contact angle measurements. Electrochemical tests in physiological solution (NaCl 0.9%) potentiodinamic polarization curves (tafel plots procedures). Based on experimental data we can conclude that the hybrid coating with higher HAp concentration is the most stable.

Mixed mode four-point testing is performed on polyurethane foams. This paper presents only the results on the stress intensity factors (SIFs) obtained experimentally for a density of 325 kg/m3, although tests were done for three foam densities. An asymmetric four-point bending setup was used for determining the critical SIFs in Mode I and Mode II, and discussions on the influence of the initial crack length on the SIF values are done. As initial crack length is increased the theoretical predictions give a better comparison to experimentally obtained results.

Composite materials based on synthetic leathers from Polyvinyl Chloride and Polyurethane with knitted fabric support are increasingly used in many sectors of industry. Two synthetic leathers have been analysed both through experimental and analytical methods in order to evaluate their elastic properties. The analytical evaluation of material elasticity was conducted based on a micromechanical approach, taking into account the Krenchel’s coefficient for Polyester fibre orientation and based on the analytical models of Leaf and Glaskin and Chamis. Experimental data was gathered using microscopic analysis and the mechanical impulse excitation test method. Results showed a good correlation with that from the experimental study. Thus, it was confirmed that the Leaf and Glaskin model and the Chamis model have a good accuracy in prediction of fibres orientation and respectively elastic properties of synthetic leather based on plain jersey.

Various techniques have been proposed for the fabrication of surgical guide templates in orthodontics. The objective of this paper is to review the associated literature and recent advancements in this field, based on design concept , materials and technique.

The surface relief map changes induced by methyl methacrylate (MMA) chemical treatment to the flat ridge lap area of the acrylic teeth in order to improve the bond strength to the denture base resin acrylic tooth interface, was investigated with a scanning electron microscopy (SEM), a classical non-invasive investigation method. The ridge lap area of 20 artificial acrylic molars was milled to flat. The samples were randomly assigned in two experimental groups, ten samples pertaining to each one of the groups. The flat surfaces of the acrylic molars were submitted to a different treatment. Group 1: (control group), no chemical treatment; Group 2: Chemical treatment with methyl methacrylate. Each specimen was submitted to SEM investigation with SEM: HITACHI TM3000 Scanning Electron Microscope. The SEM imaging captured data depicted obvious changes of the surface relief aspect of the samples treated with methyl methacrylate compared to control group. Acrylic teeth chemical treatment with methyl metahcrylate generates surface topography changes, visible in SEM imaging, topography aspects responsible for the improved adhesion of acrylic teeth to denture base resin.

Recently the removal of trace element using biodegradable polymers is important. This paper involves preparation and evaluation of chitosan/ polyethylene glycol blend served as a heavy metal removal system. The author prepared various blending system with different composition ratios and different crosslinking density. Experimental results indicated that swelling degree and thermal property of the blend film were correlated with blend ratio and crosslink density. The blend film was then investigated its metal-binding performance. Copper sorption capacity was one of major potential applications in a field of wastewater treatment.

Rubber is increasingly used in the industry of railway rolling stock, as elastic and damping element for the suspension of the vehicle or buffer and draw-gear devices. The simplicity of design, the lack of some special maintenance operations for the rubber elements and the high degree of shock and longitudinal oscillations absorption led to its increasingly use to shock isolators in order to equip railway vehicles.