The tensile properties of multiscale, hybrid, thermoplastic-based nanocomposites reinforced with nano-CaCO3 particles and micro– short glass fibers (SGF) were predicted by a two-step, three-dimensionalmodel using ANSYS finite element (FE) software. Cylindrical and cuboid representative volume elements were generated to obtain the effective behavior of the multiscale hybrid composites. In the first step, the mechanical performance of co-polypropylene/CaCO3 nanocomposite was analyzed. The thickness of the interphase layer around the nanoparticles was estimated by using differential scanning calorimetry data. In the second step, the nanocomposite (co-polypropylene/CaCO3) was considered as an effective matrix, and then the effect of micro-SGF inclusion on the corresponding effective matrix was evaluated. The FE and experimental stress-strain curves of multiscale, hybrid composites were compared at different weight fractions of the nanoparticle. The proposed two-step method can easily predict the tensile properties of multiscale, hybrid, thermoplastic-based nanocomposites.

Morphological and thermal properties of PA6/NBR nanocomposites prepared through a direct melt mixing process in an internal mixer were studied. The effects of the NBR content (10, 30, and 50%) and nanoclay loading (3, 5, and 7%) on the microstructure properties of nanocomposites have been reported and compared with PA6/NBR blends as well. The thermoplastic elastomer (TPE) nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), volume swelling in oil, differential scanning calorimeter (DSC) and dynamic mechanical thermal analysis (DMTA). XRD results show that Cloisite 30B is exfoliated into the PA6 and NBR. TEM image of the PA6/NBR/nanoclay composite confirms partial exfoliated structure of silicate layers dispersed into the both NBR and PA6 phases. The SEM photomicrograph of PA6/NBR nanocomposite shows an increasing of the rubber particles size in comparison with unfilled PA6/NBR TPE. By the presence of nanoclay, improved oil resistances of the prepared TPE nanocomposites were achieved. DSC studies show that loading of the nanoclay reduces the degree of crystallinity of the nanocomposite samples. The DMTA test shows that storage modulus of the PA6/NBR nanocomposite increases in comparison with the PA6/NBR blend. It also explains a reduction in damping by loading of the nanoclay.

Conducting polymers represent a class of materials that possess unique combination of electrical conductivity, processability, and mechanical properties. One of the most important applications of these materials is electromagnetic interference shielding which are receiving increasing attention by progress of technology and increment in the amount of electromagnetic waves sources. In the present study, attempts have been made to prepare improved electromagnetic interference shielding (EMI-SE) material of flexible composite films based on thermoplastic urethane (TPU) and graphene nanosheets. For this purpose, the prepared graphene oxide using Hummer’ s method has been thermally reduced. Then the surface of the graphene was grafted with polar and long molecules of 2-aminoethyl methacrylate (AEMA) and denoted as functionalized graphene nanosheets (FGN). Then the nanocomposites with various loadings of FGN were fabricated by solution mixing. The increased compatibility between TPU segments and FGN due to graphene modification leads to increase in electrical conductivity. Moreover, the intensified interactions and improved dispersion state of the FGN increase viscous motions and energy dissipation which leads to higher EMI SE. Results showed that the TPU based nanocomposite containing only 5 vol. % of FGN attenuate electromagnetic wave energy up to 99. 8%.

Laser ablation of a Zn target in tetrahydrofuran with different concentrations of thermoplastic polyurethane was performed with picosecond pulses. The results of ultraviolet-visible absorption, photoluminescence emission and X-ray diffraction pattern indicated that ZnO nanocomposites were produced. The influence of pulse energy, polymer concentration and argon degassing on production rate, size distribution and composite structure of nanocomposites were investigated. We tried to improve the control of size, agglomeration and composite structure of nanoparticles by polymer concentration and degassing with argon. The average particle diameters of nanocomposites which produced by 75mJ pulse energy in the liquid with 0.4 Wt% polymer concentration were in the range of 0.5 nm to 16 nm. The typical size of nanocomposites was decreased from 8 nm to 6 nm by 0.1 Wt% increasing in polymer concentration. In addition we could control agglomeration of nanocomposites by degassing with argon and increasing of polymer concentration up to 0.5 Wt%. We obtained maximum production rate by maximum laser pulse energy, 125 mJ. Polymer concentration and argon degassing were not effective in production rate.

The biopolymers based packaging materials containing nano-silver are new types of active packaging that are biodegradable and in addition, they can reduce the risk of microbial contamination in fresh and processed foods. In this research, clay (MMT) nanofillers were used for improving the mechanical properties and water vapor permeability (WVP) of the thermoplastic starch (PS) films and producing nanobiocomposites. In addition, nanosilver (AgNP) was applied for producing active antimicrobial film against Escherichia coli. According to the results of the antimicrobial test, the MMT not only did not show any antimicrobial activity but also reduced it in the films containing nano-silver. AgNP and MMT and their mixture improved barrier properties of the PS based films; In comparison to the control film, the water solubility and permeability of the PS-AgNP-MMT films were reduced about30.93 and 75.43 percent, respectively. The results of mechanical tests showed that in the films containing MMT, increasing concentration of AgNP, increased ultimate tensile strength to 5.38 MPa and reduced strain to break to 41.23 percent. Furthermore, increasing concentration of AgNP in the films containing MMT reduced UV light transmittance significantly however, increased yellowness and turbidity.

thermoplastic elastomers based on the blends of thermoplastic polyurethane (TPU) and natural rubber were prepared by a simple blend technique. The influence of the two different types of natural rubber (i.e., unmodified natural rubber (NR) and epoxidized natural rubber (ENR)) on properties of the blends was investigated. The main aim of this study was to improve heat resistance and damping properties, and also to prepare the TPU material with low hardness by blending with various amounts of natural rubber. It was found that the TPU/ENR blends exhibited superior modulus, hardness, shear viscosity, stress relaxation behavior and heat-resistant properties compared to the blends with TPU and unmodified NR. This was attributed to higher chemical interaction between the polar functional groups of ENR and TPU by improving the interfacial adhesion. It was also found that the ENR/TPU blends exhibited finer grain morphology than the blends with unmodified NR. Furthermore, lower tension set, damping factor (Tan  d) and hardness, but higher degradation temperature, were observed in natural rubber/TPU blends compared to pure TPU. This proves the formation of TPU material with high heat resistance, low hardness and better damping properties. However, the blends with higher proportion of natural rubber exhibited lower tensile strength and elongation at break.

The rheology, vulcanizational, and the physico-mechanical properties of a composition of siloxane rubber and ultra-high molecular weight polyethylene are discussed. It is shown that such materials combine elasticity and strength. Inclusions of ultra-high molecular weight polyethylene in siloxane matrix, with large-sized globular structure, imparts material a good impact resistance property. Compositions developed may be used as polymer inserts for new generation of endoprosthetic appliances for hip joints.

Applications of thermoplastic composites have developed extensively. The thermoplastic composites in comparison with the thermoset composites have many advantages. thermoplastic composites can be melted and remolded many times. The duration of manufacturing process of these composites is short, producing very tough material, and the welding ability and multiple recyclings are their further advantages. The lack of knowledge in this group of composites is the main obstacle in their development. In this review the research works in the field of residual stresses in thermoplastic composites is presented. First, a literature survey on the available research on residual stresses on thermoplastics and thermoplastic composites reinforced with short fibers is compiled. Moreover a review on the available research on residual stresses on thermoplastic composites reinforced with long fibers is presented as well. The effects of the residual stresses on these composites are discussed. Experimental techniques for the measurement of residual stresses in thermoplastic composites and the methods for reducing the existing residual stresses are studied.