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Fibers are structurally interesting components most useful in a range of applications spanning the physical and life science areas of research. These membrane (scaffold) forming fibers have been explored in applications ranging from microfilteration to advanced biological investigations in tissue engineering to controlled and targeted drug delivery. One such robust fiber generation approach investigated for over a century, which has recently been exploited, is the well-established threading process referred to as electrospinning. In this technique, single- or multi-phase media are charged within a conducting needle and later exposed to an electric field which promotes the formation of a continuous micro- to nanosized fiber(s) which over a period of collection time has been reported for forming scaffolds and membranes. This process has been explored for a wide range of polymer composite-based materials and the technique has now reached the point where it has moved into industrial production. We report here as a first example a comparable fiber to membrane fabrication approach completely driven by the coupling of a coaxial needle system with a pressure. We refer to this novel methodology as pressure-assisted spinning (PAS) where the hazardous element of high voltage (as in the case of electrospinning) is nonexistent. Hence, our discovery introduces both a directly competing fiber, scaffold to membrane fabrication approach, which is versatile and has no associated hazards as those in electrospinning. Furthermore as our technique is nonelectric field driven, the media spun into fibers could have a high electrical conductivity, which in this case has no effect on the stability in processing near-uniform fibers/scaffolds to membranes. The fabricated fibers and membranes generated by means of this approach could directly be used for a plethora of applications spanning the engineering and biological areas of research.

A thermotropic liquid crystalline polymer (TLCP) was synthesized from 4, 4'-Oxobisbenzoic acid and methylhydroquinone by low-temperature solution polycondensation. Nanocomposites of TLCP with the content of MWNTs from 0 wt% to 10 wt% were prepared by in situ polymerization. Scanning electron microscopy images showed that the MWNTs were well-separated in the TLCP matrix. Differential scanning calorimetry, thermogravimetric analyzer, X-ray diffraction, and polarized optical microscopy were used to investigate the thermal behavior, crystalline structure and liquid crystalline properties of the pure TLCP and TLCP/MWNT nanocomposites. The thermogravimetric analyses indicated that a small amount of MWNTs could improve the thermal stability of TLCP matrix. Furthermore, the result of differential scanning calorimetry demonstrated that both melt transition temperatures and isotropic transition temperatures of the hybrids were enhanced. Our study provided a design guide for CNT-filled TLCP composites which could be favorable for industrial use.

Owing to the unique microstructure and the excellent dielectric properties, carbon nanotubes (CNTs) were decorated with CoFe₂O₄ nanoparticles to synthesize the CoFe₂O₄/CNTs nanocomposites by the solvothermal method. The phase structure, morphology, magnetic properties and microwave absorption performance of the as-prepared CoFe₂O₄/CNTs were characterized and discussed by X-ray diffraction (XRD), thermal gravity analysis (TGA), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and vector network analyzer (VNA). All results indicated that the diameter of CoFe₂O₄ nanoparticles decorating on the surface of CNTs increased with the solvothermal temperature. CoFe₂O₄/CNTs prepared at 180°C, 200°C and 220°C exhibited superparamagnetism, while the other samples presented ferromagnetism at room temperature. And with the increasing solvothermal temperature, the saturation magnetization and coercivity increased up to 72 emu/g and 2000 Oe for the sample prepared at 260°C (S-26). And the reflection loss of CoFe₂O₄/CNTs nanocomposites increased with the solvothermal temperature up to -15.7 dB for S-26 with the bandwidth of 2.5 GHz.

In this work, Ni-doped ZnO/Al composites were prepared by a facile chemical co-precipitation method. The morphology and structure of the as-prepared composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS), respectively. It was found that the flake-like Al powders were successfully coated by Ni-doped ZnO nanoparticles with slight aggregation and Ni${}^{2+}$ was successfully doped into the crystal lattice of ZnO. Moreover, the effects of ZnO concentration and doped Ni concentration on the infrared emissivity of ZnO/Al composites at the waveband range of 8–14$\mu$m were studied. The results showed that the ZnO/Al composites exhibited the lowest infrared emissivity of 0.34 with 50wt.% ZnO concentration. Meanwhile, the electromagnetic parameters and microwave absorbing properties of Ni-doped ZnO/Al composites in the frequency range of 2–18GHz were explored. Significantly, 12mol.% Ni-doped ZnO/Al composites presented the lowest infrared emissivity of 0.37 and the maximum reflection loss reached $-$32.5dB at 13.6GHz with a thickness of 4.5mm. The excellent microwave absorbing properties could be attributed to the good impedance match, crystal lattice defects and interfacial polarization. It was believed that the Ni-doped ZnO/Al composites could be used as potential infrared-microwave compatible stealth materials.

Polyvinyl alcohol (PVA) was grafted on graphene nanosheets (GN) in the reduction of graphene oxide with hydrazine hydrate. The obtained GN-PVA (GP) suspension was treated with the freezing–thawing cycle to fabricate 3D porous monolithic GP materials, which were modified with carbon disulfide to introduce xanthan groups on the wall of porous materials, marked as GPCs. The characterization of GPCs confirmed that PVA was attached on the surface of GNs, and xanthan groups were effectively functionalized on the porous structures, which were composed of randomly oriented GNs. The Pb${}^{2+}$ adsorption pattern for GPC materials was investigated. The kinetic adsorption and isotherm data fit the pseudo second-order kinetic and the Langmuir isotherm models, respectively. The maximum adsorption capacity of Pb${}^{2+}$ reached 242.7mg/g. And GPCs for Pb${}^{2+}$ adsorption could be regenerated with ethylenediamine tetracetic acid (EDTA) solution for repetitious adsorption.

The properties of fiber-matrix interface pay an important effect on the mechanical properties of carbon fiber-reinforced composites. To improve the interfacial properties in carbon fiber/phenolic resin (CF/PF) composites, CF adhered CNTs (CNTs-CF) were prepared by CVD method. The surface of treated CF and the distribution of CNTs in the interfacial region of CF were detected by scanning electron microscopy (SEM). SEM images identified 700${}^{\circ }$C being the optimum growth temperature to obtain CNTs-CF, in which CNTs randomly dispersed surrounding the individual fiber surfaces. Compared to crude CF/PF composites, the tensile strength, bending strength, shear strength, impact strength, thermal conductivity at 25${}^{\circ }$C of CNTs-CF/PF composites increase by 144.5%, 59.2%, 129.0%, 75.9% and 41.7%. The improvement of mechanical properties is due to that the homogenously dispersed CNTs serve as a supplementary reinforcement to the interface and further reduce inter-laminar stress concentration. This represents an important step toward CNT-reinforced polymers with high mechanical properties.

In this work, graphene aerogels (GAs) with three-dimensional interconnected networks were prepared by chemical reduction and self-assembly of graphene oxide sheets. After microwave treatment, obtained microwave reduced graphene aerogels (MRGAs) were used in the preparation of bismaleimide (BMI) composites. The results show that the microwave treatment significantly enhanced the quality of GAs, and the three-dimensional networks in the GAs were well retained. Moreover, the MRGAs were highly efficient in endowing BMI with high electrical conductivity and excellent electromagnetic interference shielding effectiveness (EMI SE). The conductivity of MRGA/BMI composites was 42–68% higher than that of GA/BMI composites. When the filler content is 1.6 wt.%, the EMI SE of MRGA/BMI composite was 32.3% higher than that of GA/BMI composite in the X band.

In this paper, various research works have been performed on synthesis and functionalization after the invention of graphene (Gr) and its spectral properties. The reinforcing of Gr family members into the matrix leads to the development of novel composites. Its characterization in terms of morphological and physicochemical properties is required for the discovery of wide-ranging applications. This paper reviews the various emerging features and future scope for reduced graphene oxide (rGO). The possibilities of composites development through the different matrix are proposed to evaluate application potential, various fabrication techniques for Gr, and its role in improving composite properties. The work initially examines multiple ways to synthesize rGO. Its addition to different materials includes metals, metal oxides, ceramics, polymers, and organic compounds through various composite preparation techniques. Finally, this paper gives an overview of the enhancement in properties obtained due to the addition of rGO, which opens the door for a broad set of applications. This paper concludes with a comparative study that defines a suitable preparation technique according to the required material composites, desired properties, and specific applications. An attempt has been proposed to examine the exceptional feature of rGO/composite for cost-effective functions in manufacturing sectors.

Interlaminar delamination and brittle fracture of matrix have been a dilemma that fiber-reinforced composites have been faced with. Herein, the polyimide (PI) nanofiber-toughened glass fiber fiber-reinforced epoxy composites were prepared by electrospinning method and subsequent vacuum assistant resin transfer molding. The effect of spinning parameters including PI concentration, applied voltage, collector distance, jet speed and ambient humidity on the resultant fiber diameter and its distribution was systematically evaluated. The surface properties of obtained PI nanofibers were characterized by FT-IR, TG-DSC and water contact angle. The effect of PI concentration on tensile strength of PI membranes was also studied. The mode I (G${}_{\mathrm{\text{Ic}}})$ and mode II (G${}_{\mathrm{\text{IIc}}})$ interlaminar fracture toughness were measured. The results indicated that G_Ic and G_IIc increased by 127.69% and 85.33%. The improvement of interlaminar fracture toughness may be attributed to the bridging effect of PI nanofibers.