Polymer Nanocomposites For Applications Research Articles

APPLICATION OF RESPONSE SURFACE METHODOLOGY FOR MIX DESIGN OPTIMIZATION OF NANOCOMPOSITE MODIFIED ASPHALT MIXTURES

Recently the application of polymer nanocomposite has been increasingly recognized as an alternative to polymer modified binders for durable asphalt mixtures. In this study, the optimization of nanosilica and binder content for nanocomposite modified asphalt mixtures has been examined to obtain optimum quantities for higher volumetric properties. Response Surface Methodology (RSM) based on face centered central composite design (FCCCD) was utilized. Interaction effects of independent variables nanosilica and binder content on nanocomposite volumetric properties namely stability, flow, void in total mix (VTM) and voids in mineral aggregate (VMA) were evaluated. The result indicates that the individual effects of nanosilica and binder content are both important; however, the asphalt binder content had more significance on the volumetric properties. Higher Stability was achieved with the mixtures prepared with 2 nanosilica and binder content range of 5-6. Also, the mean error obtained in all the responses from optimization results are all less than 5, this indicates that predicted values are in agreement with experimental results. Furthermore, it was concluded that asphalt mixture design with high performance properties, optimization using RSM is a very effective approach. © Int. J. of GEOMATE.

Study Of Thermal And Mechanical Properties Of Clay/Polymer Nanocomposite Synthesized Via Modified Solution Blending

ABSTRACTThe incorporation of layered nano-silicates in polymer matrix greatly enhances the properties of the polymer. At present, there are many applications of polymer nanocomposites including coatings and architectural, they are also parts of automotive and construction industry among others. The acrylics employed at the present study were based on butyl acrylate (BA), styrene (STY), and methacrylic acid (MAA), and the nano-clay was Na-montomorillonite (MMT). The MMT clay was added to the polymer, which is the mixing matrix in a physical state solution called blend. Furthermore, their mechanical, thermal and wettability of especially prepared acrylic montmorillonite (MMT) nanocomposites were performed. By increasing the MMT in the polymer matrix concentration the Young’s modulus tends to increase it by an order of magnitude. However, by Differential Scanning Calorimetry (DSC), the thermograms show an increase in the glass transition temperature of nanocomposites for all weight percentages of MMT. Also, the wetting angle was determined, in order to know how much water is retained on the surface of the nanocomposite; the results showed that by increasing the particle of nano clay in the polymer matrix will induce a hydrophobic property to the nanocomposite.

Reuse of red algae waste for the production of cellulose nanocrystals and its application in polymer nanocomposites

Red algae is widely available around the world and its exploitation for the production of agar products has become an important industry in recent years. The industrial processing of red algae generates a large quantity of solid fibrous wastes, which constitutes a source of serious environmental problems. In the present work, the utilization of red algae waste as raw material to produce high-quality cellulose nanocrystals (CNC) has been investigated, and the ability of the as-isolated CNC to reinforce polymer has been studied. Red algae waste was chemically treated via alkali, bleaching and acid hydrolysis treatments, in order to obtain pure cellulose microfibers and CNC. The raw waste and the as-extracted cellulosic materials were successively characterized at different stages of treatments using serval analysis techniques. It was found that needle-like shaped CNC were successfully isolated at nanometric scale with diameters and lengths ranged from 5.2±2.9 to 9.1±3.1nm, and from 285.4±36.5 to 315.7±30.3nm, respectively, and the crystallinity index ranged from 81 to 87%, depending on the hydrolysis time (30, 40 and 80min). The as-extracted CNC were used as nanofillers for the production of polyvinyl alcohol (PVA)-based nanocomposite films with improved thermal and tensile properties, as well as optical transparency. It is shown that the addition of 8wt% CNC into the PVA matrix increased the Young’s modulus by 215%, the tensile strength by 150%, and the toughness by 45%. Additionally, the nanocomposite films maintained the same transparency level of the neat PVA film (transmittance of ∼90% in the visible region), suggesting that the CNC were dispersed at the nanoscale.

Applications of polymer nanocomposites as encapsulants for solar cells and LEDs: Impact of photodegradation on barrier and optical properties

The search for higher efficiency organic materials and device architectures has been of greatest interest in the organic photovoltaic community, but the issue concerning the stability of devices has received little attention. The next generation of lighting industry, phosphor-converted white light-emitting diodes (LEDs) is becoming a mature technology which needs extended lifetime. As promising as the performances of a material are, long-term stability is just as important as initial efficiency. Organic Solar Cells (OSC) have to be encapsulated to overcome the problem of their sensitivity to oxygen and moisture. High quality encapsulation layers are then critical for improving the life span of OSC. To meet the encapsulation requirements, different approaches have been adopted such as single layer and multilayer encapsulation. A variety of materials have been developed to face the barrier issue, but the challenge is still to develop high gas barrier materials with required photostability.Recent research focused on nanocomposites is based on various kinds of nanofillers, such as phosphors or zeolites. Phosphor particles display an emission in the visible domain upon a UV excitation, and the luminescent polymer/phosphor nanocomposites can be used for eco-energetic lighting devices such as LEDs or as multifunctional coatings for Organic Solar Cells. Zeolites as nanofillers are expected to improve water barrier properties, which makes polymer/zeolite nanocomposites good candidates for encapsulation of organic solar cells. The photostability of the materials and the durability of the barrier properties are then challenging for developing new applications in this domain.

Functionalization of synthetic fibrous materials using nanosized polymer carriers

Applications of polymer nanocomposites for the functionalization of textiles were reviewed. Authors’ experimental data on preparation of bioactive nonwoven materials via preliminary modification by biopolymer nanoparticles imparting to them the ability to effectively adsorb functional substances were presented.

50th Anniversary Perspective: Are Polymer Nanocomposites Practical for Applications?

The field of polymer nanocomposites has been at the forefront of research in the polymer community for the past few decades. Foundational work published in Macromolecules during this time has emphasized the physics and chemistry of the inclusion of nanofillers; remarkable early developments suggested that these materials would create a revolution in the plastics industry. After 25 years of innovative and groundbreaking research, PNCs have enabled many niche solutions. To complement the extensive literature currently available, we focus this Perspective on four case studies of PNCs applications: (i) filled rubbers, (ii) continuous fiber reinforced thermoset composites, (iii) membranes for gas separations, and (iv) dielectrics for capacitors and insulation. After presenting synthetic developments we discuss the application of polymer nanocomposites to each of these topic areas; successes will be noted, and we will finish each section by highlighting the various technological bottlenecks that need to be over...

Comparative study on the properties of poly(trimethylene terephthalate) -based nanocomposites containing multi-walled carbon (MWCNT) and tungsten disulfide (INT-WS2) nanotubes

Multi-walled carbon (MWCNT) and tungsten disulfide (INT-WS2) nanotubes are materials with excellent mechanical properties, high electrical and thermal conductivity. These special properties make them excellent candidates for high strength and electrically conductive polymer nanocomposite applications. In this work, the possibility of the improvement of mechanical, thermal and electrical properties of poly(trimethylene terephthalate) (PTT) by the introduction of MWCNT and INT-WS2 nanotubes was investigated. The PTT nanocomposites with low loading of nanotubes were prepared by in situ polymerization method. Analysis of the nanocomposites' morphology carried out by SEM and TEM has confirmed that well-dispersed nanotubes in the PTT matrix were obtained at low loading (<0.5 wt%). Thermal and thermo-oxidative stability of nanocomposites was not affected by the presence of nanotubes in PTT matrix. Loading with INT-WS2 up to 0.5 wt% was insufficient to ensure electrical conductivity of PTT nanocomposite films. In the case of nanocomposites filled with MWCNT, it was found that nanotube incorporation leads to increase of electrical conductivity of PTT films by 10 orders of magnitude, approaching a value of 10−3 S/cm at loading of 0.3 wt%. Tensile properties of amorphous and semicrystalline (annealed samples) nanocomposites were affected by the presence of nanotubes. Moreover, the increase in the brittleness of semicrystalline nanocomposites with the increase in MWCNT loading was observed, while the nanocomposites filled with INT-WS2 were less brittle than neat PTT. Copyright © 2016 John Wiley & Sons, Ltd.

Ultrathin Nanosheets of Organic-Modified β-Ni(OH)2 with Excellent Thermal Stability: Fabrication and Its Reinforcement Application in Polymers.

β-Nickel hydroxide (β-Ni(OH)2), which combines two-dimensional (2D) structure and the catalytic property of nickel-containing compounds, has shown great potential for the application in polymer nanocomposites. However, conventional β-Ni(OH)2 exhibits large thickness, poor thermal stability, and irreversible aggregation in polymer matrices, which limits its application. Here, we use a novel phosphorus-containing organosilane to modify the β-Ni(OH)2 nanosheet, obtaining a new β-Ni(OH)2 ultrathin nanosheet with excellent thermal stability. When compared to pristine β-Ni(OH)2, the organic-modified β-Ni(OH)2 (M-Ni(OH)2) maintains nanosheet-like structure, and also presents a small thickness of around 4.6 nm and an increased maximum degradation temperature by 41 °C. Owing to surface organic-modification, the interfacial property of M-Ni(OH)2 nanosheets is enhanced, which results in the exfoliation and good distribution of the nanosheets in a PMMA matrix. The addition of M-Ni(OH)2 significantly improves the mechanical performance, thermal stability, and flame retardancy of PMMA/M-Ni(OH)2 nanocomposites, including increased storage modulus by 38.6%, onset thermal degradation temperature by 42 °C, half thermal degradation temperature by 65 °C, and decreased peak heat release rate (PHRR) by 25.3%. Moreover, it is found that M-Ni(OH)2 alone can catalyze the formation of carbon nanotubes (CNTs) during the PMMA/M-Ni(OH)2 nanocomposite combustion, which is a very helpful factor for the flame retardancy enhancement and has not been reported before. This work not only provides a new 2D ultrathin nanomaterial with good thermal stability for polymer nanocomposites, but also will trigger more scientific interest in the development and application of new types of 2D ultrathin nanomaterials.

A facile strategy for functionalizing silica nanoparticles by polycarbonate degradation and its application in polymer nanocomposites

The degraded polycarbonate (PC) chains were successfully grafted onto the surface of silica nanoparticles (nano-SiO2) by melt blending. Covalent linkage (Si–O–C bond) was formed between the degraded PC chains and nano-SiO2 under the condition of strong shear force and high temperature. The alcoholysis between carbonate and Si–OH groups, coupled with the condensation reaction between silicon hydroxyls and hydroxyl end groups of degraded chains, mainly contributed to the formation of Si–O–C bond. As expected, the tensile strength and toughness of PC were simultaneously enhanced by incorporating functionalized SiO2. The improvement in tensile properties was attributed to the strong interfacial adhesion between functionalized SiO2 and PC matrix.

Polymer nanocomposites for energy applications

energy production, energy transportation, and storage, has grown rapidly in recent years due to the increase in fossil fuel consumption, environmental issue and global warming. Nanomaterials with different morphologies, properties and structures (e.g. barium titanate nanoparticles, carbon nanotubes, ZnO nanowires) offer superior chemical, mechanical or physical properties compared to their micro meter-scale counterparts. Accordingly, they are potential candidate materials for clean energy applications such as the energy storage, fuel cells, and solar cells (ISBN: 978-0-12-407796-6). The nanomaterials can be incorporated into polymers at low loading levels to form nanocomposites with greater mechanical flexibility, tailored properties and functionalities. These include bipolar plates of fuel cells (DOI: 10.1039/c0ee00689k), high-energy density capacitors, solid polymer electrolytes, and hybrid polymer/nanoparticle solar cells (DOI: 10.1016/ j.jcis.2011.12.016). Nanofillers offer larger interfacial area that allows better interaction with the polymer matrix. Polymers provide structural support and protection for nanomaterials during their industrial service lives. A wide variety of polymers can be selected for making nanocomposites for various fields of energy applications depending on the designed chemical, physical and mechanical properties. The major challenges of achieving high-performance polymer nanocomposites are the attainment of uniform dispersion of nanofillers in the polymer matrix and the manipulation of nanofiller/polymer interfaces. Typical approaches include surface modification of nanofillers via covalent and noncovalent functionalization. Significant research efforts have been devoted by chemists and materials scientist for developing polymer nanocomposites with novel functionalities using improved fabrication techniques recently. For instance, polymeric materials with high dielectric constant (k) and low loss find useful application for making supercapacitors. The !-phase of polyvinylidene fluoride is known to exhibit excellent ferroelectric and piezoelectric effects. This phase can be increased to ~46% by adding 0.5 wt% carbon nanotubes and processed through electrospinning. The process stretches polymer solution uniaxially under an electric potential. It can be further increased over 90% by mechanical drawing (DOI: 10.1021/jp4011026). To reduce dielectric loss, core-shell nanoparticle strategy emerges as a powerful method for preparing high-k nanocomposites especially filled with conducting nanomaterials (DOI: 10.1002/adma.201401310). To fully realize widespread commercial applications of polymer nanocomposites, it is necessary to develop cost-effective processes for the mass production of these materials in large quantities.

Effect of multiwalled carbon nanotube loading on the properties of Nafion® membranes

Abstract

Facile hydroxylation of halloysite nanotubes for epoxy nanocomposite applications

Polymer nanocomposites have been extensively investigated over the past two decades, resulting in a wide range of applications because of their excellent performance. Halloysite, a type of naturally occurring aluminosilicate, has attracted increasing interest in polymer nanocomposite applications, especially for the enhancement of mechanical properties owing to its tubular structure. Herein, we report a facile approach to achieve a high level of dispersion of halloysite nanotubes (HNTs) in epoxy by treating HNTs with a low concentration of sodium hydroxide (NaOH). The NaOH treatment resulted in the formation of hydroxyl groups on the surface of HNTs, leading to a much higher level of dispersion of HNTs in water, organic polar solvents, and epoxy matrix. The higher density of external silanol groups (Si–OH) of hydroxylated HNTs (h-HNTs) was confirmed by X-ray photoelectron spectroscopy (XPS) characterization. Such a higher level of dispersion and stronger interface led to simultaneous enhancement in both the stiffness and the toughness of epoxy/h-HNT nanocomposites. Systematic characterizations were performed to investigate the related stiffening and toughening mechanism. The implication of the present findings is discussed.

A Review on Photopolymers for Polymer Nanocomposite Applications

A Review on Photopolymers for Polymer Nanocomposite Applications

Environmentally friendly synthetic route to the monodispersed ZnO nanoparticles on large-scale

Monodispersed spherical ZnO nanoparticles with narrow size distribution have been synthesized by environmentally friendly wet-chemical route. The synthesis utilizes zinc acetate as precursor, which is hydrolyzed in the ethanol-2% H2O solution to form the ZnO nanoparticles. Sodium oleate was employed as surface capping agent to control the size at 5–200nm and to improve the dispersion properties of ZnO nanoparticles. The blue-shift of the adsorption peaks at about 360nm could be detected obviously by increasing the Na+:Zn2+ molar ratio. The X-ray diffraction (XRD) results indicated that the synthesized ZnO had a pure hexagonal wurtzite structure. The photoluminescence spectrum (PL) gave two main emission peaks centering at 410nm and 550nm. Complicated procedure or high temperature was not required in this reaction process. And the expansion experiment was conducted, which could demonstrate that yield of ZnO products could be up-scaled to the gram-scale or even more without affecting the property of nanoparticles. Moreover, the recycling solution was also available in this reaction system, which made it environmental friendly and improved the solutions׳ reusability rate. As their good long carbon-chain surface coating, the ZnO nanoparticles are well suitable for the applications in polymer nanocomposites and related fields.

Polymer Nanocomposites in Building, Construction

Nanotechnology is an enabling technology allowing to do new things in almost every conceivable area. Initial efforts to exploit nanoscience/nanotechnology development in the construction industry focused mainly on understanding phenomena and improving performance of existing materials. Recently, polymer nanocomposites started to be introduced in other areas like the construction industry. Polymer nanocomposite field attracts considerable attention these days due to a variety of potential practical applications. They have offered a great opportunity in sustainable construction/green building application due to their efficiency and environmental protection. Their use in the construction industry is still less known outside the research area. This paper is a short review of recent studies done in this area, taking into account that some nano based materials are ready to be used by the construction industry. This review covers some studies done in the polymer nanocomposite applications in construction basic materials such as concrete, asphalt, thermal and sound insulation, adhesives, coatings, plastics and in energy.

Facile large-scale synthetic route to monodisperse ZnO nanocrystals

We report an efficient, robust and up-scalable synthetic route to small, spherical, well stabilized, narrow disperse, crystalline ZnO nanoparticles. The synthesis utilizes Zn-oleate or Zn-stearate as precursors, which are hydrolyzed in polar organic solvents to obtain ZnO nanoparticles in diameters in the range of 3–5nm on multi-gram scales. The synthesis exploits the use of oleates and stearates as good precursors and stabilizing agents together with the hydrolysis route to obtain small ZnO nanoparticles in a well-controlled way. The nanoparticles show the characteristic bright green fluorescence emission, and can be precipitated, dried, and redispersed in common organic solvents without aggregation. Because of their good steric stabilization and hydrophobic coating, these nanoparticles are very suitable for applications in polymer nanocomposites for UV-absorption and opto-electronic applications.

Processing, Properties, and Applications of Polymer Nanocomposites Based on Layer Silicates: A Review

ABSTRACTThe nanocomposites are materials, which involve fillers in the nanometer scale, yielding substantial improvements. Polymer‐layered silicate nanocomposites have received much attention during the past decade and have great interest both in the academic field and in industry, since they often give more attractive improvement to material properties than both micro‐ and macrocomposite materials. This extensive review presents recent studies in polymer nanocomposites based on layered silicate. The background, morphology, preparations, and properties of these materials are discussed. The review covers and discusses various modern methods and equipments in the preparation of nanocomposites, deeply focusing on the morphology of nanocomposites and its effects on the overall properties. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2013, 32, 21368; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21368

On Nanoparticles Release from Polymer Nanocomposites for Applications in Lightweight Automotive Components

Nano and micro reinforced glass fibre-polymer composites have been manufactured to investigate different effect such as filler type, filler size and matrix materials on the particle emission during low velocity impact test. Nano and micro- silica, as well as nanoclay reinforced crash cones were prepared with a two step extrusion process and final injection moulding of the structures. The addition of secondary filler into the glass-fibre reinforced polymer composites had significant influence on the mechanical behaviour of the material as well as on the particle emission. In general, nano and ultrafine airborne particles were emitted from all investigated materials. However, composite filled with nanoclay emitted higher amounts of particles than those filled with nano and microsilica. One reason for the increase of particle emission of the nanoclay filled composites was the change of the failure behaviour of the matrix. However, similar results of particle emission were obtained for both nano and microsilica fillers, which in general did not vary significantly from the results obtained from traditionally reinforced glass fibres polymer composites.

Application of polymer nanocomposites in the nanomedicine landscape: envisaging strategies to combat implant associated infections

This review article presents an overview of the potential biomedical application of polymer nanocomposites arising from different chemistries, compositions, and constructions. The interaction between the chosen matrix and the filler is of critical importance. The existing polymer used in the biomedical arena includes aliphatic polyesters such as polylactide (PLA), poly(ε-caprolactone) (PCL), poly(p-dioxanone) (PPDO), poly(butylenes succinate) (PBS), poly(hydroxyalkanoate)s, and natural biopolymers such as starch, cellulose, chitin, chitosan, lignin, and proteins. The nanosized fillers utilized to fabricate the nanocomposites are inorganic, organic, and metal particles such as clays, magnetites, hydroxyapatite, nanotubes chitin whiskers, lignin, cellulose, Au, Ag, Cu, etc. These nanomaterials are taking root in a variety of diverse healthcare applications in the sector of nanomedicine including the domain of medical implants and devices. Despite sterilization and aseptic procedures the use of these biomedical devices and prosthesis to improve the patient's 'quality of life' is facing a major impediment because of bacterial colonization causing nosocomial infection, together with the multi-drug-resistant 'super-bugs' posing a serious threat to its utility. This paper discusses the current efforts and key research challenges in the development of self-sterilizing nanocomposite biomaterials for potential application in this area.

Polymer Nanocomposites and Cr(VI) Removal from Water

The progress in nanocomposites is varied and used in many industries. Nanocomposites can be made with a variety of enhanced physical, thermal and other unique properties. They have properties that are superior to conventional microscale composites and can be synthesized using simple and inexpensive techniques. The addition of small amounts of nanoparticles to polymers has been able to enable new properties for the composite materials. In recent years polymer nanocomposites have received significant attention because of their importance both from academic and industrial point of view. Composites, Nanocomposites in general and Polymer nanocomposites in particular have been discussed. Different type of nanocomposites and their preparations have been reviewed in brief. Application of polymer nanocomposites for the removal of Cr(VI) from aqueous solution has been described taking the examples from the literature as well as our own results. It is found that nanocomposites can be used in an effective manner for the removal of Cr(VI), a highly toxic metal ion.