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Abstract The solution casting method was utilized to synthesize nanocomposite films of chitosan (Cs)/CuO, Cs/graphene oxide (GO), carboxymethyl cellulose (CMC)/TiO2, CMC/GO, sodium alginate (Na Alg)/TiO2, and Na-Alg/GO owing to their various applications. The influence of CuO, TiO2 and GO concentration on the optical properties of Cs, CMC and Na-Alg films was studied by UV-Vis Spectroscopy. The absorbance of Cs, CMC and Na-Alg increased with increasing the filler content, thus reflecting the dependence of Cs, CMC, and Na-Alg properties on the nanofiller content, and confirming the interactions between individual polymers and CuO, TiO2 and GO nanoparticles. The obtained absorbance values were then used to calculate the absorption coefficient and, hence, the optical band gap values. The characteristic absorption bands of CuO and TiO2 underwent a redshift by increasing the filler content. The results showed that the optical band gap of Cs, CMC, and Na-Alg decreased with filler content, and they possessed 1, 2 and 2 band gaps respectively. The obtained results recommended that Cs, CMC, and Na-Alg nanocomposites can be used in optoelectronic devices.

The electrical properties of conductive carbon black (CB) nanoparticles (0.1wt percent) doped thin films made of poly(ethylene oxide) (PEO) filled with varying amounts of the electrolyte potassium alum salt and doped with conductive carbon black (CB) nanoparticles (0.1wt percent) have been investigated. The dependence of the activation energy of the composites on frequency, temperature, and filler content was studied using the AC impedance technique. The current research looked at how activation energy changed with frequency (200-1000 kHz) and temperature (30-55oC) for composites with varied potassium alum salt concentrations: 0, 2, 4, 8, 12, and 16 wt. percent. The activation energy (Ea) values measured exhibited frequency, temperature, and filler content relationships. According to polarization processes, the activation energy of the produced sheets decreases with the potassium alum salt content in the composite and decreases with the temperature. With increasing frequency, the activation energy of the produced thin films decreases.

Rutting is considered as the most generated distress in Iraqi roads as a result of the high temperature and excessive traffic load. So, it is essential to utilize polymer modified binder to increase the performance of pavements. The objective of this paper is to assess the effect of aggregate gradation and filler content on the rutting formation of Colored Hot Mix Asphalt CHMA. The HMA was colored by using iron oxide as filler to produce red HMA. Two blends were used: fine and coarse with two different types of filler iron oxide for CHMA and limestone for conventional HMA with two filler content 6% and 10%. Neat (AC 40-50) and modified asphalt (AC 40-50 + 4%SBS) were used. Tests are held on adding 4% Styrene Butadiene Styrene )SBS( by the weight of neat asphalt (AC 40-50) to raise the performance grade by two grades from PG (64-16) to PG (76-16) [1] and [2]. The wheel tracking test is used to assess the rut depth of the CHMA. The test results showed that the using iron oxide with neat asphalt increase the rut depth resistance by 200 and 400 failure load cycles than mixtures using limestone (cycles that mix reach 25 mm rut depth) for fine and coarse mix respectively. Also, the effect of gradation shows that the fine mixture fails at 4000 cycles while the coarse mixture fails at 1800 cycles for 6% limestone mixtures.  Increasing the iron oxide content from 6% to 10% leads to increase the failure load cycles by 2200 and 1200 cycles for fine and coarse mixture respectively using modified asphalt. The fine mixture with 10% iron oxide using modified asphalt gives the best performance with 7000 cycles than the coarse mixture with 10% filler content and modified asphalt with 4000 cycles. irrespective the filler and type of binder, the dense mixtures using iron oxide as filler exhibit better resistance to rutting formation than coarse mixtures.

The participation of the electronic subsystem of graphene nanoparticles in heat transfer on the interfaphase surface with epoxy polymer, its participation in the thermodestruction processes of epoxy matrix and the concentration interval of the subsystem's influence on the thermal destruction of the polymer matrix are investigated. For such purpose, epoxy resin composites with oxidized and non-oxidized graphene nanoparticles have been used.The particles were obtained by electrochemical method and those are characterized by the same dispersion and analogical of defect spectra. The particles have the same crystal structure, however in composites with oxidized graphene, the participation of the electronic subsystem in thermophysical processes on the interfacial surface is blocked by the atomic layer of adsorbed oxygen. Сomposites of epoxy resin filled with the same particles of nonoxidized and oxidized nanoparticles in the filler content 0.0, 1.0, 2.0, and 5.0 wt%. The multilayered graphene particles were studied by X-ray diffraction analysis (XRD) and Raman spectroscopy (RS) methods. It was shown that the graphene particles are the 2D dimensional structures with about of 100 layers. Desorption curves of epoxy and its composites have been obtained using a programmable thermal desorption mass-spectroscopic (TDMS) technique for fragments with 15≤ m/z ≤108 and temperature interval 35 - 800 оС. The activation energy of desorption was determined from the Wigner-Polanyi equation as 35 - 150 kJ/mol, temperature and mass dependences of the quantity of desorbed atomic fragments have been calculated. It were established the graphene electron subsystem takes part in polymer structure thermodestruction for epoxy composites with nonoxidized graphene enhancing their heat resistance at graphene content С ≤ 1 wt%. With increasing filler content, the thermodestruction behavior in pristine epoxy and its composites with nonoxidized and oxidized graphene is analogical. The thermodestruction characterizes by the stepwise variations in the desorption intensity of atomic fragments. The electron subsystem of graphene particles does not participate in the heat resistance variations.

Three polyester-based composite materials were prepared with different volume fractions of three types of fillers (i.e. cement, gypsum and limestone) with the aim of improving the tensile and liquid absorption properties of the former for the synthetic marble industry. The tensile strength, modulus of elasticity, toughness, ductility and liquid absorption percentage of the composites were characterized. Results revealed an increase in the modulus of elasticity, tensile strength and toughness of all prepared composites, as well as a decrease in their ductility, with increasing filler amount. The liquid absorption values of all composites increased with increasing filler content. The composites were able to absorb water extensively but absorbed benzene, kerosene and gasoil minimally.

The aim of this work involved comparing the effect graphite and shungite have on the properties of dielectric elastomer-based materials. For this reason, dielectric elastomer–Sylgard (S) was filled with 1, 3, 5, 10, and 15 wt.% of graphite (G) and shungite (Sh). The structure of the obtained materials was studied by means of scanning electron microscopy and atomic force microscopy. The influence of the introduced additives on the thermal stability of the obtained composites was evaluated using thermogravimetry. Moreover, the mechanical properties and the dielectric constant of the elastomer with an addition of graphite and shungite were determined. Obtained results allowed us to establish that the presence of graphite as well as shungite significantly influences mechanical as well as dielectric properties. Additionally, the optimum mass of additives, allowing to increase the dielectric constant without the significant decrease of strain at break, was indicated. In the case of materials containing graphite, regardless of the filler content (1–15 wt.%), the mechanical as well as the dielectric properties are improved, while in the case of composites with an addition of shungite exceeding the 5 wt.% of filler content, a reduced tensile strength was observed.

The use of wood plastic composites (WPC) is growing very rapidly in recent years, in addition, the use of plastics of renewable origin is increasingly implemented because it allows to reduce the carbon footprint. In this context, this work reports on the development of composites of bio-based high density polyethylene (BioHDPE) with different contents of pinecone (5, 10, and 30 wt.%). The blends were produced by extrusion and injection-molded processes. With the objective of improving the properties of the materials, a compatibilizer has been used, namely polyethylene grafted with maleic anhydride (PE-g-MA 2 phr). The effect of the compatibilizer in the blend with 5 wt.% has been compared with the same blend without compatibilization. Mechanical, thermal, morphological, colorimetric, and wettability properties have been analyzed for each blend. The results showed that the compatibilizer improved the filler–matrix interaction, increasing the ductile mechanical properties in terms of elongation and tensile strength. Regarding thermal properties, the compatibilizer increased thermal stability and improved the behavior of the materials against moisture. In general, the pinecone materials obtained exhibited reddish-brown colors, allowing their use as wood plastic composites with a wide range of properties depending on the filler content in the blend.

Generally, adding the electroconductive fillers into the polymer matrix is a popular approach to endow the shape memory polymers (SMPs) with electroconductivity. Therefore, the shape memory effects (SMEs) of thermally induced SMPs can also be triggered by the electrical current. In essence, both the thermally activated and electrically activated SMEs share the same driving mechanism without considering the effect of heat conduction. In the paper, the constitutive model for the thermally induced SMPs filled with nano-carbon powder is briefly introduced. Then, a modified model is developed to characterize the effects of filler, deformation, and moisture on the electrical conductivity for the first time. After developing the correlation of electric field with Joule heat, the simulation is executed to display the free recovery of the shape memory polymer composites (SMPCs) with different filler content. It is found that the recovery ratio decreases with the increase of carbon powders for the SMPCs with filler content above the percolation threshold. Besides, a good recovery ratio can also be achieved through the application of a lower voltage.

The process of ethanol dehydration via pervaporation was performed using alginate membranes filled with manganese dioxide and a mixed filler consisting of manganese dioxide on magnetite core MnO2@Fe3O4 particles. The crystallization of manganese dioxide on magnetite nanoparticle surface resulted in a better dispersibility of this mixed filler in polymer matrix, with the preservation of the magnetic properties of magnetite. The prepared membranes were characterized by contact angle, degree of swelling and SEM microscopy measurements and correlated with their effectiveness in the pervaporative dehydration of ethanol. The results show a strong relation between filler properties and separation efficiency. The membranes filled with the mixed filler outperformed the membranes containing only neat oxide, exhibiting both higher flux and separation factor. The performance changed depending on filler content; thus, the presence of optimum filler loading was observed for the studied membranes. The best results were obtained for the alginate membrane filled with 7 wt.% of mixed filler MnO2@Fe3O4 particles. For this membrane, the separation factor and flux equalled to 483 and 1.22 kg·m−2·h−1, respectively.