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Main goals like technical innovation, costs and respect for the environment urge us to discover finer, lighter, biodegradable, and more «intelligent» materials in their functionality. The development of industrial design is motivated by criteria such as the environment, sustainability, the need for lightweight products, manufactured with fewer components and integrating various functions. As experts in new materials and technologies for the development of innovative products, we work closely with international research institutes as part of our projects. We want to create materials that combine such properties in the most efficient way, interacting with their close environment and the environment in general and, based on their features, to be transformed through various processes in completely different materials. The goal of our work is to compare different existing materials with a new bio-based material using quantifiable measurement indicators and sensory measurement indicators. The purpose of this article is to provide a few elements that can be used as a guide in establishing a quantitative impact assessment strategy based on the use of sensory evaluation techniques. In the framework of our presentation, we will focus mostly on comparing the materials via a metrological tool for quantifying tactile characteristics likely to be correlated to the `ground truth` that constitutes a sensory profile.

Can polymer-infiltrated florapatite glass ceramic produced from waste materials, such as clam shell and soda lime silicate glass, be used in prosthetic rehabilitation? The purpose of this study is to investigate the effect of Si/Ca ratio on the mechanical properties of Nb-Bi-Ce doped polymer-infiltrated fluorapatite ceramic networks (PICNs) produced from clam shell (CS) and soda lime silicate (SLS) glass by conventional melt-quench technique, used as a dental ceramic. PICNs comprising Si/Ca at four different weight percentage ratios: 1.27% (PICN-1), 2.15% (PICN-2), 4.12% (PICN-3) and 12.6% (PICN-4) were prepared (n=10). The powder mixtures in four different ratios were compressed in a rectangular prism shaped mold and subjected to equal pressure from all sides in a cold isostatic press, followed by heat treatment at 750C for 3 h. Then complete vacuum infiltration was done with a polymer mixture then low temperature firing was applied leading to the formation of the PICNs. Wear behavior and 3-point bending properties were evaluated and specimens were analyzed using scanning electron microscopy (SEM). The friction and wear properties were determined by means of a pin-on-disk tribotester. Since the flexural strength test did not show normal distribution, Kruskal Wallis test was performed in independent groups, p[0.05. There is a significant difference of flexural strength values between the groups (p=0.032), it was determined that the difference was between the PICN-1 and PICN-4 groups (p=0.037). In the analysis of wear scar, abrasion grooves were also observed. The results of this study showed that high Ca and Si content in CS and SLS glass, respectively, encourages the use of waste materials in the production of PICNs intended to be used in prosthetic rehabilitation. The composition of PICNs produced from waste materials affected flexural strength and wear behavior. Increasing the Si/Ca ratio was found to support the mechanical properties of experimental PICN and that experimental PICNs can be considered as high potential candidates for dental applications.

The study establishes a theoretical evaluation trough several models concerning the dielectric properties of some new eco-composites made of a cellulosic derivative matrix – hydroxypropyl methylcellulose (HPMC) – in which distinct sorts of fillers (ceramic, metallic and bio-derived) were introduced. The investigation describes the impact of the filler addition on the dielectric constant, the dielectric breakdown, and finally how these two factors are contributing to the electric energy density of purposed eco-composites. After incorporation of the reinforcement agents, the dielectric constant significantly increases comparatively with the matrix, as a function of the type of filler used. Moreover, by assessing of the dielectric breakdown, it is observed that with the increase of filler quantity, this parameter slightly decreases for all samples. The data concerning the electric energy density reveal that, by filler insertion in the HPMC matrix, an improvement occurs, especially for the barium titanate system owing to its large dielectric constant. These data are promising for design of new eco-composites having improved dielectric features as demanded for green energy storage devices. Since the materials have biodegradable and biocompatible character, they also have importance in bio-related applications.

The industrial grade hollow beads were divided into three particle sizes of 40 mesh, 60 mesh and 80 mesh and added into the epoxy resin material matrix to prepare porous foam composites. The quasi-static compression experiments were performed on porous foam composites at room temperature, and the stress-strain curves of quasi-static compression processes were analyzed separately for different particle sizes. According to the characteristics of the compression curve of porous foam materials, the representative characteristic parameters of each stage are extracted separately. The fracture characteristics of the microscopic samples of the compressed material specimens were observed by electron microscopy, and the deformation patterns of the composite materials were analyzed. And combined with SEM pictures to analyze the form of microbead crushing and matrix pore collapse mode, according to which the particle size suitable for this matrix is 60 mesh and the mass fraction of microbeads is 10%.

Polyethylene (PE) materials have been widely used in industrial and living fields such as natural gas pipelines, drainage pipes, sewage pipes. Punch test is an interesting tool for studying the mechanical properties of materials. However, the deformation behavior involved in punch test is complicated, it is, therefore, essential to investigate the influence of punch test conditions on the mechanical properties of PE materials. Punch tests have been carried out on PE specimens with different punching speed (0.01, 0.1, 1, 10 and 100mm/min) and different punch head diameters (4, 6, 8 and 10mm). The experimental results show that the maximum load from the load-displacement curve increases with the increase of the punch head diameter under the same punch speed. When the punch speed is slow, the force-displacement curve of PE specimens contains four typical stages, namely, elastic stage, yield stage, strain softening stage and strain hardening stage. However, the PE specimen breaks before reaching the strain hardening stage when the punch speed is fast. Similarly, the maximum load increases with the increase of punch speed when the same punch head diameters are used. Furthermore, a three-dimensional finite element (FE) model of PE specimens subjected to punch load has been established to further analyze the deformation and failure behavior. A good agreement between the simulation results and the punch test data is achieved.

To analyze the implant overdentures components as following: morphology and composition aspects of several small diameter systems, evaluating both the implant and the retention system (1); biomechanical characteristics of some of the polymers used for manufacturing the overdenture base (2). An experimental in vitro study was carried out through optic microscopy to analyze the metallic structure of dental implants components and anchor systems. The marketed products analyzed were mini1SKY (Bredent) and 3M ESPE MDI Mini dental implant (3M ESPE). A Zeiss microscope with Kohler illumination was used. Samples from polymeric materials commonly used for overdenture based (i.e. Duracryl and Superacryl) were analyzed by 3 point bending test by Tira device. In the case of the mini1SKY system (Bredent), the dental implant has the typical structure of marketed pure titanium that went through thermomechanical processing, resulting in a higher rate of granulation, and the matrix has a completely different structure, as it is a monophasic structure specific to materials that crystalize in the cubic system of the stainless steels. In the case of the 3M ESPE MDI system, the implant and the matrix have a similar microstructure, specific to a Ti-6Al-4V beta alloy annealed with an extremely fine rate of granulation. Duracryl and Superacryl samples fractured variable (frequently close to the midline) and were similar in regard to the value of breaking force. Knowledge of the materials of the components of implant overdenture guide their selection from the point of view of biocompatibility, resistance and ensuring denture retention.

In this present research work, Poly(azomethine), ZnO, TiO2, poly(azomethine)/TiO2 and poly(azomethine)/ZnOnanocomposites were synthesized. Prepared nanocompositewas characterized by FourierTransform-Infrared spectroscopy, UV-Visiblespectroscopy, PowderX-raydiffraction, band gap, EDAX and SEM. The Photocatalytic activity of the samples was evaluated for the degradation of MethylorangeandAlizarin red S under natural sunlight. The effects of dye concentration were studies for the decolorization of MethylorangeandAlizarin red S. The degradationefficiency,reactionkinetics and isotherm studies revealed that the Polyazomethine /ZnO(PNZ) and poly(azomethine)/TiO2(PNT) nano-composites have shown excellent photocatalytic activity than PAZ, ZnO and TiO2.At optimum dye concentrations of 10ppm Methyl orange and Alizarin Red S shows maximum degradation efficiency was 87% and 86% usingPNZ and PNT nanocomposites asaphotocatalysts at 5 h contact time. FT-IR, UV-Visible spectroscopy, SEM and EDAX were used to describe the samples after the photocatalytic investigation. To examine the effect of decolorisation of dyes using synthesized photocatalysts Pseudo first order kinetic, pseudosecond order model, Langmuir, Freundlichisothermsstudieswere carriedout and also followed by intra-particle diffusion model, whereas diffusion is not only the rate-controlling step. The results show that the degradation capacity decreases with an increase in solution temperature from303 K to 333 K. The thermodynamics parameters were evaluated.

Nowadays, research is focused on using bio-degradable natural fibre-based composites for secondary structural members. The present study aims to investigate the effect of fiber loading and surface treatment on the mechanical, vibrational, and viscoelastic properties of short, randomly oriented Abelmoschus Esculentus fiber-reinforced epoxy composites. The composite was fabricated by reinforcing various weight percentages of Abelmoschus Esculentus in epoxy resin by hand lay-up method and tested for tensile, flexural, and impact tests as per ASTM standards. Further, the fibres are treated with alkali to evaluate their effect on the mechanical properties of composites. The analysis indicated that fiber loading had a significant impact on the mechanical properties of the composite, with the maximum tensile strength of 27.8 MPa being obtained at a fiber loading of 20 volume %. The surface treatment of the fiber with 2% NaOH solution increased the tensile strength by 34%. All composite specimens were subjected to vibration analysis. The results showed that composite reinforced with 20% fibre loading provided superior mechanical and damping qualities. Dynamic Mechanical Analysis revealed that the Storage Modulus (E’) improved with the addition of Abelmoschus Esculentus fiiber.

The purpose of this paper was to obtain new hybrid composite materials (HCM) with applications in electromagnetic shielding and their characterization using new methods. The paper presents 6 experimental models (EM) of new hybrid composite materials (HCM) with applications in the electromagnetic shielding and their characterization using new methods. EMs were obtained by extrusion and melt injection, with different ratios of HDPE/hybrid NiFe2O4/Ag mixture concentrations: 100/0 - I0; 97/3 - I1; 95/5 - I2; 93/7 - I3; 90/10 - I4 and 80/20 - I5. The characterizations performed within this work are imposed and correlated with the operating conditions of these materials. Thus, we studied the behavior of polymer composite materials with hybrid fillers, under the action of different degradation factors such as ionizing radiation, UV radiation and moisture. Following the tests performed, the experimental model I5, composite with maximum ferrite concentration, i.e. 20 %, was chosen as the optimal variant. It was aimed to identify the degree of degradation of the developed composite materials, as a function of the variation of tan δ with frequency, at different aging/ conditioning cycles. The originality element of the paper consisted in determining the life time remaining of the HCM until the moment it needs to be replaced, by an original method protected of by an invention patent.

SiO2 nanoparticle were used in aPolyphenylsulfone (PPSU) matrix to obtain nanofiltration membranes used in the pharmaceutical sector to remove pollutants from the water processes. In this study was investigated the influence of SiO2 nanoparticles on the PPSU membranes performance at different concentration of polymer and at six different concentrations of SiO2. Adding SiO2 like additive in the PPSU membrane matrix, the permeability increases due to the higher porosity. Increasing the polymer concentration, the pores are smaller and the permeation properties are decreasing. The affinity for water of membrane surface is higher when nanoparticles are added in the polymer matrix. Adding 0.3 wt.% SiO2 the permeation properties are increasing with more than 10% in comparison with membranes without nanoparticles.