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In this study, the nanocomposite membranes were electrospun using conventional polymers, including polyvinyl chloride (PVC), thermoplastic polyurethane (TPU) and polycarbonate (PC) at different levels of incorporation of the γ-alumina nanoparticles (1, 3 and 5 wt.%). Morphological investigation using SEM images showed that the diameters of the nanofibers were in the range of 155-491 nm. The energy dispersive spectroscopy (EDS) analysis and FTIR test revealed the presence of the γ-alumina nanoparticles (NPs) and characteristic chemical groups in electrospun nanocomposite membranes (ENCMs). The contact angle test showed that the hydrophilic features of the membranes improved with the incorporation of γ-alumina NPs with the decrease of contact angle from 80° to 27°. Mechanical tests exhibited a drop in tensile strength and strain of the nanocomposite membranes by adding more γ-alumina NPs to the neat membrane. Filtration efficiency of ENCMs was evaluated using the submerged system with the humic acid (HA) solution. Results showed that the permeation flux of the membranes increased with an increase in the content of the γ-alumina NPs (from 49 to 102 L.m-2.h-1). The irreversible fouling ratio (IFR) of the membranes was also improved by increase in the content of the γ-alumina NPs up to 3 wt.%. Results also demonstrated the better anti-fouling performance for the blended nanofiber membrane with 3 wt.% of the nanoparticles (flux recovery ratio, FRR=94.4 %). HA rejection test also proved the enhanced foulant removal (99.6 %) of ENCM containing 3 wt.% γ-alumina NPs.

Relaxation processes in metallocene and Ziegler–Natta isotactic polypropylenes were studied using 1H MAS NMR spectroscopy. 1H MAS NMR spectra and laboratory-frame spin-lattice relaxation times T 1(1H) were measured within the temperature range 30–190 °C, which covers the glass transition relaxation and melting processes of both polymers. Splitting of the peak related to protons in amorphous regions of the studied samples into three sharp peaks at elevated temperatures made it possible to determine the spin-lattice relaxation times T 1(1H) for particular iPP proton groups. The melt-state NMR spectra of ZN-iPP display three sharp peaks with three additional weak peaks positioned on the less shielded side. Entanglements of ZN-iPP chains are suggested as a possible source of these additional peaks. The spectra of m-iPP indicate substantially fewer entanglements due to its lower molecular weight compared with that of ZN-iPP. The temperature dependences of the relaxation times T 1(1H) relating to specific groups of ZN-iPP were shown to reach minima associated with the motions of amorphous chain segments (glass transition relaxation), which are very close to the melting temperature and minima associated with the melting process. Each of the T 1(1H) temperature dependences for m-iPP shows only one minimum associated with the melting process. When the particular relaxation times T 1, min relating to the minima that occur above the melting temperatures were considered, and these relaxation times were compared for the same proton groups in different samples, significant differences in the relaxation times were observed between samples. Polymer chain motion was more restricted in melted ZN-iPP than in m-iPP, as inferred from the T 1, min values.

A new aromatic heterocyclic diamine monomer containing bi-benzimidazole unit, 2,2-bis(4′-aminophenyl)-5,5-bi-1H-benzimidazole, was synthesized from 2,2-bis(4′-nitrophenyl)-5,5-bi-1H-benzimidazole (BNPBBI) prepared via the reaction of 3,3′,4,4′-biphenyltetramine and p-nitrobenzaldehyde with a high yield. Their compositions and chemical structures containing polybenzimidazole backbone were characterized by FTIR, 1H NMR and elemental analysis. A series of aromatic polyimides containing the heterocyclic moiety in the main chain were prepared by the reaction of BAPBBI with various aromatic dianhydrides of 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalic anhydride or pyromellitic dianhydride. The polymers possess a high glass transition temperature of >415 °C and a good thermal stability up to 566 °C with a 5 % weight loss. The combination of polybenzimidazole and polyimide via introducing BAPBBI into the main chains provides the rigid structure, and macromolecular interactions are thus enhanced, resulting in the outstanding mechanical properties. These polyimides exhibit the strong tensile strength of 201 to 327 MPa, and the ultrahigh tensile moduli of 10.7 to 15.5 GPa without post stretching.

Thermal stability of [(CH3SiH)30(C6H5SiCH3)70]n a hydropolysilane copolymer, in vacuum and its crosslinking reactions with vinylic silanes as crosslinking agents was evaluated in order to obtain high yields of oxygen-free silicon carbide ceramics. It was found that the polymer was thermally stable in vacuum up to 140 °C for 20 hrs based on Fourier transform infrared spectroscopy analysis. The crosslinking reactions of the polymer occurred to various extents depending on the type of vinylic silanes used as evidenced by Fourier transform infrared spectroscopy, ultraviolet spectroscopy, gel permeation chromatography, thermogravimetry and solubility data. The additions of vinylic silanes to Si-H in the hydropolysilane were found to obey anti-Farmer's rule, despite Farmer's addition of unsaturated hydrocarbons to Si-H.

The synthesis of magnetite nanoparticles (MNP) using waste iron tailing as one of the starting materials and its use in preparation of MNP/polyurethane (MNP/PU) nanocomposites with bio-based PU were described. A comparison of XRD patterns, FT-IR and UV–vis diffuse reflectance spectra of neat MNP, neat PU and MNP/PU nanocomposites indicated the incorporation of MNP in PU resin. The SEM and TEM micrographs showed nearly uniform dispersion of MNP in MNP/PU nanocomposites. Both thermal stability and electrical conductivity of MNP/PU nanocomposites were increased with increase of MNP loading while MNP addition significantly improved the tensile properties of PU. The magnetic measurements revealed a transition from superparamagnetic behaviour of neat MNP to ferromagnetic in MNP/PU at lower MNP content. The MNP/PU nanocomposites may be exploited further for electronic and optoelectronic applications.

Phosphorus-containing organic–inorganic hybrid flame retardant with core–shell structure (Salen-PZN-Cu@Ni-Mof) was prepared. Thermogravimetric analysis (TGA) showed that when the additive amount was only 3wt%, the introduction of Salen-PZN-Cu@Ni-Mof significantly improved the thermal stability of epoxy resin (EP) composites. The results of the cone calorimeter test showed that adding 3wt% Salen-PZN-Cu@Ni-Mof made the peak of heat release rate (PHRR), total heat release (THR), smoke production rate (SPR) and total smoke production (TSP) of epoxy resin composites reduced by 30.4%, 10.8%, 29.5% and 6.8%, respectively. It was proved that Salen-PZN-Cu@Ni-Mof could significantly enhance the fire safety of epoxy resin composites, which was attributed to the synergetic combination of the flame retardant effect of the phosphazene structure itself, the catalyzed carbon formation of various metal ions and the porous mof materials with strong adsorption properties. Besides, it was found that the Ni-Mof could strengthen the compatibility between the flame retardant and the EP matrix effectively through the tensile test. The novel core–shell structure flame retardant Salen-PZN-Cu@Ni-Mof promised to be a functional filler that integrated features of flame retardancy and high ductility.

In modern era, natural and biodegradable polymer matrices have gained more attention in order to replace harmful materials that cause environmental damage. To deal with such types of issues, in this research work, we have prepared simple, fast, and eco-friendly curcumin/montmorillonite (MMT)-clay-loaded bacterial cellulose (BC) bioscaffolds via dip-coating and freeze-drying process following time parameters 06 h, 12 h, and 24 h. These newly developed curcumin/MMT-clay/BC nanocomposites were characterized by morphological and structure analysis. So in contrast, the molecular interaction between bacterial cellulose and curcumin/MMT-clay was determined by the FTIR analysis. The morphological structures of prepared nanocomposites were observed by DSC and TGA to determine the thermal stability and EDS, XRD, and SEM analysis to determine the elemental composition in curcumin/MMT-clay/BC nanocomposites. Moreover, the contact angle analysis determined the enhancement in contact angle with obtained values θ = 21.5°, θ = 31.8°, and θ = 38.6°, respectively, to demonstrate the trend from hydrophilic to hydrophobic and illustrate that the prepared films were fully covered with curcumin/MMT-clay which can be observed in SEM analysis. So, the surface morphological characterizations of curcumin/MMT-clay/BC nanocomposites reveal that curcumin/MMT-clay can be counterpart as a filler material via dip-coating and freeze-drying process and has good thermal stability. The machinal characteristics of curcumin/MMT-clay/BC nanocomposites were revealed by the strength analysis, which shows the slight reduction in strength values 6.1%, 5.9%, and 4.8%, respectively, while the overall properties of curcumin/MMT-clay/BC nanocomposites were improved in comparison to pure bacterial cellulose. In addition, this novel curcumin/MMT-clay/BC nanocomposites illustrate the excellent antistatic properties after 24-h coating time of curcumin/MMT-clay with good (static half period; 6.585 ± 0.45, instantaneous electrostatic voltage (V); 510.30 ± 3.60) significances. Moreover, the outstanding ultraviolet-resistive properties of curcumin/MMT-clay/BC (24-h coating) were observed with excellent (T.VUA/%; 0.88 ± 0.9), (T.VUB/%; 0.65 ± 0.08), (UPF; 1135.30 ± 15.5) significances. So, consequentially, this study illustrates that curcumin/MMT-clay/BC nanocomposite can be a novel green bioscaffold as antistatic and UV-resistive material in many routine life food packaging, drugs, medical as well as in other protective applications.

The alternating maleic acid–2-vinylnaphthalene copolymer was synthetized and characterized. The amphiphilic polyelectrolyte adopts a pseudomicellar conformation in aqueous solution. The hydrophobic microdomains are formed by the naphthalene groups and the water solubility is conferred by the hydrophilic maleic acid groups. The two-step dissociation of polyelectrolyte was studied by potentiometric titrations and the conformational transition was investigated by viscometry and fluorescence techniques. By increasing the neutralization degree over an αN ~ 0.2, an expansion of the polymer coil takes place from a compact to a loose or extended form, but the hydrophobic microdomains formed by the naphthalene groups are present on the whole neutralization range. The investigation of the naphthalene fluorescence quenching by different transition metal ions shows an extremely high quenching efficiency by Cu2+ ions. The ionic strength influences the polyelectrolyte conformation and the fluorescence quenching process. The maleic acid–2-vinylnaphthalene copolymer can be used for the solubilization of polynuclear aromatic compounds or other sparingly water-soluble organic compounds or for the design of fluorescent sensors.

The alteration in some properties of electron beam (EB) cured ethylene-propylene diene rubber (EPDM) reinforced by polyethylene terephthalate (PET) fiber was investigated in this study. Bonding system Resorcinol/Hexamethylenetetramine/Silica (RHS) was used to enhance the fiber/EPDM adhesion and to maintain optimum composite strength properties. Mechanical properties of composites namely; tensile strength, hardness and modulus at 100 % elongation have been enhanced by adding PET fibers and increasing irradiation dose. Moreover, the effect of fiber loading and irradiation dose on the soluble fraction behavior of the composite in benzene was also investigated. The soluble fraction of the composites decreased with increasing the fiber loading and irradiation dose. The extent of fiber alignment and strength of fiber-rubber interface adhesion were analyzed from the anisotropic swelling measurements. In addition, thermal stability of the composites was increased. Besides, the mechanical properties like tensile strength and stiffness were improved by thermal ageing. Scanning electron microscopy (SEM) for the fractured surfaces and Wide- angle X- ray diffraction (WAXD) of the investigated samples confirmed that the adhesion occurred between fibers and EPDM.