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The extrusion-calendering process was realized successfully to produce the potential and easily recyclable single-polymer composites (SPCs). This approach makes it possible to produce SPCs continuously and avoids the drawbacks involving a long cycle time, inconvenient operation, and expensive cost. Low-density polyethylene (LDPE) reinforced with ultrahigh molecular weight polyethylene (UHMWPE) fabric was prepared. Based on orthogonal and single factor experiments, the effects of die temperature, screw speed, and rolls speed were investigated. The tensile and interfacial properties of the LDPE/UHMWPE SPCs were evaluated through tensile and T-peel tests. The best tensile strength of 78.8 [+ or -] 7 MPa was obtained in the LDPE/ UHWMPE SPCs with a fiber volume fraction of 11.2% and a void content of 0.01%. The peel strength was significantly improved, 22.4 N/10 mm was achieved. The morphology observed using scanning electron microscopy (SEM) further determined the fiber-matrix interfacial adhesion and the effects of processing parameters. POLYM. ENG. SCI., 58:2156-2165, 2018. [C] 2018 Society of Plastics Engineers, INTRODUCTIONThe recyclability of composites still reminds a key topic to the pressures of resource and environment in recent years. However, heterogeneous compositions and special structures in traditional polymer composites strictly [...]

This review presents the nature, fundamental structure, and various morphologies of native polyvinyl alcohol) (PVA) matrix. It highlights recent advances in pure PVA and its composites containing various nanofillers that have potential applications in various fields. Over half a century, PVA is known as an auspicious material for diverse applications. The review focuses on the structural, mechanical, optical, and electrical properties of PVA-based nanocomposites. The study highlights a new promising area of optoelectronics for possible applications of PVA nanocomposites. The challenges and opportunities in working with various PVA nanocomposites are discussed along with some future recommendations are presented to strengthen this area of research. POLYM. ENG. SCI., 58:2119-2132, 2018. [C] 2018 Society of Plastics Engineers, INTRODUCTIONNanotechnology is a multidisciplinary field that has been blooming recently [1]. Its significance is increasing in various fields including biomedical, sensors, and computing [2]. Polymeric materials are being used as [...]

A novel carbon nanohybrid Pickering stabilizer was synthesized via a hydrothermal reaction of 2-ethyl-4-methylimidazole (EMI), graphene oxide (GO), and carbon nanotubes (CNTs). The EMI/GO/CNTs encapsulated poly (methyl methacrylate) (PMMA) microspheres were achieved via suspension polymerization after the formation of stable oil-in-water (o/w) Pickering emulsion using the as-prepared EMI/GO/CNTs stabilizer, which were used to elaborate PMMA-based nanocomposites through compression molding technique. Infra-red (IR) spectra and contact angle (CA) measurements showed that EMI/GO/CNTs nanohybrids was amphiphilic in nature. Mechanical tests and scanning electron microscope observation were performed to characterize the properties and microstructure of the resulting nanocomposites. PMMA nanocomposites containing networking EMI/GO/CNTs nanohybrids exhibited the maximum flexural strength of 73.1 MPa and compressive strength of 218.4 MPa at a GO-to-CNTs mass ratio of 6:1, respectively. The influences of the amount of EMI/GO/CNTs stabilizer and the ratio of GO to CNTs on the structure and properties of PMMA nanocomposites were discussed., INTRODUCTIONGraphene is a new type of monoatomic layer of carbonaceous nanomaterials with unique two-dimensional (2D) planar structures. The [sp.sup.2]-bonded carbon atoms in graphene constitute the honeycomb lattice structure of the [...]

The Polyurethane (PU)/hydrophobic silica gel (HSG) fibrous membranes with the hydrophobic and breathable surface was fabricated via electrospinning. By employing the HSG incorporation, mechanical properties, thermal stability, and waterproofness of the composite membranes could be improved. The porous structure of the membranes would be regulated by tuning the temperatures of thermal treatment. When HSG content increased to 3 wt%, the PU/HSG composite membranes possessed remarkable tensile strength of 6.3 MPa and high water contact angle (WCA) of 134[degrees]. Furthermore, the maximum WCA (142[degrees] [+ or -]1[degrees]), good hydrostatic pressure (5.45 kPa), large water vapor transmission rate (8.05 kg/[m.sup.2]/day), and high air permeability (9.25 L/[m.sup.2]/s) of the composite membranes could be achieved by heat treatment at 120[degrees]C. The resultant membranes performed significantly better when compared to the pure PU membranes under the same conditions, such as the higher tensile strength (100%), better waterproofness (200%), and stronger breathablity (25%). POLYM. ENG. SCI., 58:1381-1390, 2018. [C] 2017 Society of Plastics Engineers, INTRODUCTION Electrospinning microporous membranes with high waterproofness and good breathability have attracted tremendous attention, owning to the characteristics that can restrict the permeation of liquids and toxic gas, but allow [...]

A review of methods of surface molecular imprinting using micro- and nanodimensional inorganic materials, including nanostructured ones, as substrates and methods of their application to analysis for increasing the selectivity and sensitivity of the determination. Molecularly imprinted polymers play an increasingly important role in the development of methods for the separation and preconcentration of organic substances and inorganic ions. Their main advantage over traditional adsorbents used in analytical chemistry consists in a combination of adsorption properties with the selective recognition of template molecules or related compounds. Recently much attention has been paid to surface molecular imprinting as a technology ensuring not only an increase in the efficiency of the selective preconcentration of analytes, but also in the sensitivity of their subsequent determination in complex matrixes, and also the reduction of the cost of the adsorbent material using substrates for preparing thin films of molecularly imprinted polymers on their surface., Author(s): E. V. Bulatova [sup.1] , Yu. Yu. Petrova [sup.1] Author Affiliations: (Aff1) grid.446175.5, Institute of Natural and Technical Sciences, Surgut State University, , 628412, Surgut, Russia Molecular imprinting is [...]

Semi-crystalline polypyrrole:polystyrene sulfonate (PPy:PSS) composites were synthesized successfully after passing through the micro-pores of filter paper. Filter paper was used as a tunnel to channel the diffusion speed of the initiator and to separate the PSS chains as a function of the occupied pore volume. Fourier transform infrared spectroscopy (FT-IR) suggested the specific bonding structures of the formed PPy:PSS. The crystallographic structures of the PPy:PSS composites were analyzed by X-ray diffraction based on various pore sizes of the filter paper used. The crystallinity dependence of the conductivity was evaluated using a standard four-point probe. A series of PPy: PSS samples with different crystallinity exhibited electrical conductivity ranging from 0.007 S/cm to 0.062 S/cm., INTRODUCTION Polypyrrole (PPy) has been attracted considerable interest because of its good electrical conductivity, environmental stability, and easy synthesis process [1-5]. On the other hand, pristine PPy is insoluble, infusible, [...]

Butyl acrylate (BA) with acrylated castor oil (ACO) was grafted onto porous polypropylene (PP) granules by grafting polymerization. Crosslinked copolymer microdomains which functioned as rubber phase to improve the toughness of PP were filled into the pores of PP granules. The sizes of crosslinked copolymer microdomains were controlled in the range of 0.1-1 [micro]m in PP matrix. The results of fourier transform infrared spectroscopy and scanning electron microscope of PP-g-(BA-co-ACO) after extracted by acetone confirmed that BA and ACO were grafted onto PP successfully. The effects of comonomer ratio, initiator content and comonomer content on grafting percentage (GP) and grafting efficiency (GE) were investigated. The GP of PP-g-(BA-co-ACO) could be up to 21.3% with the comonomer content increasing to 25%. The crosslinked copolymer decreased the melting flow index and the relative crystallinity of PP. Dynamic mechanical thermal analysis showed that the glass transition temperature of PP decreased slightly from 22[degrees]C to 15[degrees]C. The addition of 5% comonomer content led to an increase of notched impact strength from 1.96 to 3.81 kJ/[m.sup.2] (nearly doubled) and a marginal decrease in the tensile strength of PP. Then with further addition of comonomer, the notched impact strength increased to 8.98 kJ/[m.sup.2] while the tensile strength was 29.37 MPa., INTRODUCTION Polypropylene (PP) is one of the most widely used thermoplastic polymer materials due to its desirable properties and low cost. However, the non-polar nature and low temperature brittleness of [...]

Polyvinyl alcohol) (PVA) composite fibers with high fraction of multiwalled carbon nanotubes (MWCNTs) were prepared by gel spinning process. Here, a modified process was introduced to prepare concentrated PVA/MWCNTs/ DMSO spinning dope, and to attain good dispersion of MWCNTs in the fibers. The final composite fibers were studied by thermogravimetric analyzer (TGA), Fourier transform infrared spectrometer (FTIR), Raman spectroscopy, differential scanning calorimetry (DSC), and WAXD analysis. The total content of MWCNTs in PVA composite fibers, from 5 to 30 wt%, was confirmed by TGA analysis. FTIR and Raman measurements demonstrated the existence of strong hydrogen interaction between MWCNTs and PVA matrix. SEM images of composite fibers showed smooth surface, regular cross-section shape and good dispersion of MWCNTs in the fibers. DSC analysis showed that the crystallinity first increased and then decreased with the increase of MWCNTs contents. It can be concluded that low concentration of MWNCTs can act as nucleation sites for crystallization of PVA component, and large amount of MWCNTs may impede the crystallization of PVA component. The WAXD analysis results indicated that the crystal orientation of the PVA component in PVA composite fibers is almost identical at the same drawn ratio. Polarized Raman analysis indicated a small increase in MWCNTs orientation for the composite fibers. The mechanical properties tests showed that the composite fibers exhibit significant improvement in tensile strength and modulus as compared to the neat PVA fibers. The composite fibers also showed sustained growth in electrical conductivity., INTRODUCTION Multiwalled carbon nanotubes (MWCNTs) are one of the promising candidates for advanced reinforcing nanofillers for high strength, light weight and functional polymer composite fibers because of their extremely high [...]

Ultraviolet (UV) irradiation can cause a severe damage to textiles, such as color fading, polymer degradation, and mechanical strength decrease. The aim of this study was to deposit inorganic UV blocking agents onto polyamide/ aramid dyed fabric using atomic layer deposition (ALD) technique to produce functional fabrics that are resistant to high intensity UV light. Scanning electron microscopy (coupled to energy-dispersive spectroscopy), X-ray photoelectron spectroscopy, and thermogravimetry studies demonstrated that Ti[O.sub.2], [Al.sub.2][O.sub.3], and Ti[O.sub.2]/[Al.sub.2][O.sub.3] nanolayer could be successfully deposited onto the fiber surface. The dyed fabrics with different ALD coatings showed excellent high intensity UV resistance and were also more resistant to high intensity UV-induced mechanical strength damage. These results suggested that the ALD technology could be effective technique to improve the properties of dyed fabrics. POLYM. ENG. SCI., 55:1296-1302, 2015., INTRODUCTION It is known that UV irradiation can cause a severe damage to textiles in tenns of color, mechanical strength, and human physiological comfort [l]. In order to improve the [...]