Polymer Nanocomposites II

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Composites and Nanocomposites".

Deadline for manuscript submissions: closed (31 January 2021) | Viewed by 46956

Special Issue Editors


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Guest Editor
Department of Engineering, University of Palermo, RU INSTM, Viale delle Scienze, 90128 Palermo, Italy
Interests: polymer processing; mechanical behaviour of polymer-based systems; rheological behaviour of polymer-based systems; green composites; biocomposites; nanocomposites; biodegradable polymers; polymer blends; degradation and recycling of polymer-based systems
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Guest Editor
Department of Engineering, RU INSTM of Palermo, University of Palermo, Viale delle Scienze ed.6, 90128 Palermo, Italy
Interests: polymer composites and nanocomposites; polymer blends; bioplastics; rheology; degradation and stabilization of polymer systems; antimicrobial polymeric systems
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Nearly two years ago, the Polymers Special Issue on polymer nanocomposites collected 27 high-value papers, which were cited about 300 times. These results witnesses the importance of the research on polymer nanocomposites and prompt the creation of this new Special Issue, which is to be included in the new Polymer Nanocomposites section of Polymers.

Polymer nanocomposites are new polymeric systems which show very interesting properties and behaviours that are drastically different from those of microcomposites. Moreover, these systems can be considered very useful for many industrial applications. However, these polymer systems give rise to new challenges in polymer science and polymer technology because of the nanometric dimensions of the inert fillers. Indeed, despite their interesting properties, there are only a few established industrial applications. Morphology, rheology, processing, and degradation behaviour are not yet completely understood. Consequently, this Special Issue aims to reflect the current efforts and progress made in this field.

Prof. Francesco Paolo La Mantia
Prof. Luigi Botta
Guest Editor

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Keywords

  • Nanocomposites
  • Nanobiocomposites
  • Morphology
  • Processing
  • Rheology
  • Degradation
  • Recycling

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Published Papers (13 papers)

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Research

Jump to: Review

39 pages, 77196 KiB  
Article
The Tensile Behaviour of Highly Filled High-Density Polyethylene Quaternary Composites: Weld-Line Effects, DIC Curiosities and Shifted Deformation Mechanisms
by David Viljoen, Matthieu Fischer, Ines Kühnert and Johan Labuschagné
Polymers 2021, 13(4), 527; https://doi.org/10.3390/polym13040527 - 10 Feb 2021
Cited by 8 | Viewed by 2908
Abstract
The interactive effects between additives and weld lines, which are frequent injection-moulding defects, were studied in high-density polyethylene (HDPE) and compared to weld-line-free reference samples. These materials were formulated around a D- and I-optimal experimental design, based on a quadratic Scheffé polynomial model, [...] Read more.
The interactive effects between additives and weld lines, which are frequent injection-moulding defects, were studied in high-density polyethylene (HDPE) and compared to weld-line-free reference samples. These materials were formulated around a D- and I-optimal experimental design, based on a quadratic Scheffé polynomial model, with up to 60 wt% calcium carbonate, masterbatched carbon black and a stabiliser package. Where reasonable and appropriate, the behaviours of the systems were modelled using statistical techniques, for a better understanding of the underlying trends. The characterisations were performed through the use of conventional tensile testing, digital image correlation (DIC) and scanning electron microscopy (SEM). A range of complex interactive effects were found during conventional tensile testing, with DIC used to better understand and explain these effects. SEM is used to better understand the failure mechanics of some of these systems through fractography, particularly regarding particle effects. A measure is introduced to quantify the deviation of the pre-yield deformation curve from the ideal elastic case. Novel analysis of DIC results is proposed, through the use of combined time-series plots and measures quantifying the extent and localisation of peak deformation. Through this, it could be found that strong shifts in the deformation mechanisms occur as a function of formulation and the presence/absence of weld lines. Primarily, changes are noted in the onset of continuous inter- and intralamellar slip and cavitation/fibrillation, seen through the onset of localised deformation and stress-whitening. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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15 pages, 11411 KiB  
Article
Thermomechanical Analysis of Isora Nanofibril Incorporated Polyethylene Nanocomposites
by Cintil Jose, Chin Han Chan, Tan Winie, Blessy Joseph, Abhimanyu Tharayil, Hanna J Maria, Tatiana Volova, Francesco Paolo La Mantia, Didier Rouxel, Marco Morreale, David Laroze, Lovely Mathew and Sabu Thomas
Polymers 2021, 13(2), 299; https://doi.org/10.3390/polym13020299 - 19 Jan 2021
Cited by 9 | Viewed by 2627
Abstract
The research on cellulose fiber-reinforced nanocomposites has increased by an unprecedented magnitude over the past few years due to its wide application range and low production cost. However, the incompatibility between cellulose and most thermoplastics has raised significant challenges in composite fabrication. This [...] Read more.
The research on cellulose fiber-reinforced nanocomposites has increased by an unprecedented magnitude over the past few years due to its wide application range and low production cost. However, the incompatibility between cellulose and most thermoplastics has raised significant challenges in composite fabrication. This paper addresses the behavior of plasma-modified polyethylene (PE) reinforced with cellulose nanofibers extracted from isora plants (i.e., isora nanofibrils (INFs)). The crystallization kinetics of PE–INF composites were explained using the Avrami model. The effect of cellulose nanofillers on tuning the physiochemical properties of the nanocomposite was also explored in this work. The increase in mechanical properties was due to the uniform dispersion of fillers in the PE. The investigation on viscoelastic properties confirmed good filler–matrix interactions, facilitating the stress transfer. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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17 pages, 2056 KiB  
Article
Dispersion of Graphite Nanoplates in Polypropylene by Melt Mixing: The Effects of Hydrodynamic Stresses and Residence Time
by Luís Lima Ferrás, Célio Fernandes, Denis Semyonov, João Miguel Nóbrega and José António Covas
Polymers 2021, 13(1), 102; https://doi.org/10.3390/polym13010102 - 29 Dec 2020
Cited by 3 | Viewed by 2370
Abstract
This work combines experimental and numerical (computational fluid dynamics) data to better understand the kinetics of the dispersion of graphite nanoplates in a polypropylene melt, using a mixing device that consists of a series of stacked rings with an equal outer diameter and [...] Read more.
This work combines experimental and numerical (computational fluid dynamics) data to better understand the kinetics of the dispersion of graphite nanoplates in a polypropylene melt, using a mixing device that consists of a series of stacked rings with an equal outer diameter and alternating larger and smaller inner diameters, thereby creating a series of converging/diverging flows. Numerical simulation of the flow assuming both inelastic and viscoelastic responses predicted the velocity, streamlines, flow type and shear and normal stress fields for the mixer. Experimental and computed data were combined to determine the trade-off between the local degree of dispersion of the PP/GnP nanocomposite, measured as area ratio, and the absolute average value of the hydrodynamic stresses multiplied by the local cumulative residence time. A strong quasi-linear relationship between the evolution of dispersion measured experimentally and the computational data was obtained. Theory was used to interpret experimental data, and the results obtained confirmed the hypotheses previously put forward by various authors that the dispersion of solid agglomerates requires not only sufficiently high hydrodynamic stresses, but also that these act during sufficient time. Based on these considerations, it was estimated that the cohesive strength of the GnP agglomerates is in the range of 5–50 kPa. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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17 pages, 2670 KiB  
Article
Effect of Filler Synergy and Cast Film Extrusion Parameters on Extrudability and Direction-Dependent Conductivity of PVDF/Carbon Nanotube/Carbon Black Composites
by Beate Krause, Karina Kunz, Bernd Kretzschmar, Ines Kühnert and Petra Pötschke
Polymers 2020, 12(12), 2992; https://doi.org/10.3390/polym12122992 - 15 Dec 2020
Cited by 9 | Viewed by 3320
Abstract
In the present study, melt-mixed composites based of poly (vinylidene fluoride) (PVDF) and fillers with different aspect ratios (carbon nanotubes (CNTs), carbon black (CB)) and their mixtures in composites were investigated whereby compression-molded plates were compared with melt-extruded films. The processing-related orientation of [...] Read more.
In the present study, melt-mixed composites based of poly (vinylidene fluoride) (PVDF) and fillers with different aspect ratios (carbon nanotubes (CNTs), carbon black (CB)) and their mixtures in composites were investigated whereby compression-molded plates were compared with melt-extruded films. The processing-related orientation of CNTs with a high aspect ratio leads to direction-dependent electrical and mechanical properties, which can be reduced by using mixed filler systems with the low aspect ratio CB. An upscaling of melt mixing from small scale to laboratory scale was carried out. From extruded materials, films were prepared down to a thickness of 50 µm by cast film extrusion under variation of the processing parameters. By combining CB and CNTs in PVDF, especially the electrical conductivity through the film could be increased compared to PVDF/CNT composites due to additional contact points in the sample thickness. The alignment of the fillers in the two directions within the films was deduced from the differences in electrical and mechanical film properties, which showed higher values in the extrusion direction than perpendicular to it. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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21 pages, 8559 KiB  
Article
Effect of Iron-Oxide Nanoparticles Impregnated Bacterial Cellulose on Overall Properties of Alginate/Casein Hydrogels: Potential Injectable Biomaterial for Wound Healing Applications
by Rahul Patwa, Oyunchimeg Zandraa, Zdenka Capáková, Nabanita Saha and Petr Sáha
Polymers 2020, 12(11), 2690; https://doi.org/10.3390/polym12112690 - 14 Nov 2020
Cited by 50 | Viewed by 5659
Abstract
In this study we report the preparation of novel multicomponent hydrogels as potential biomaterials for injectable hydrogels comprised of alginate, casein and bacterial cellulose impregnated with iron nanoparticles (BCF). These hydrogels demonstrated amide cross-linking of alginate–casein, ionic cross-linking of alginate and supramolecular interaction [...] Read more.
In this study we report the preparation of novel multicomponent hydrogels as potential biomaterials for injectable hydrogels comprised of alginate, casein and bacterial cellulose impregnated with iron nanoparticles (BCF). These hydrogels demonstrated amide cross-linking of alginate–casein, ionic cross-linking of alginate and supramolecular interaction due to incorporation of BCF. Incorporation of BCF into the hydrogels based on natural biopolymers was done to reinforce the hydrogels and impart magnetic properties critical for targeted drug delivery. This study aimed to improve overall properties of alginate/casein hydrogels by varying the BCF loading. The physico-chemical properties of gels were characterized via FTIR, XRD, DSC, TGA, VSM and mechanical compression. In addition, swelling, drug release, antibacterial activity and cytotoxicity studies were also conducted on these hydrogels. The results indicated that incorporation of BCF in alginate/casein hydrogels led to mechanically stronger gels with magnetic properties, increased porosity and hence increased swelling. A porous structure, which is essential for migration of cells and biomolecule transportation, was confirmed from microscopic analysis. The porous internal structure promoted cell viability, which was confirmed through MTT assay of fibroblasts. Moreover, a hydrogel can be useful for the delivery of essential drugs or biomolecules in a sustained manner for longer durations. These hydrogels are porous, cell viable and possess mechanical properties that match closely to the native tissue. Collectively, these hybrid alginate–casein hydrogels laden with BCF can be fabricated by a facile approach for potential wound healing applications. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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16 pages, 5941 KiB  
Article
Effects of Accelerated Weathering on Degradation Behavior of Basalt Fiber Reinforced Polymer Nanocomposites
by Ummu Raihanah Hashim, Aidah Jumahat, Mohammad Jawaid, Rudi Dungani and Salman Alamery
Polymers 2020, 12(11), 2621; https://doi.org/10.3390/polym12112621 - 6 Nov 2020
Cited by 12 | Viewed by 2683
Abstract
This work aims to give insight on the effect of accelerated weathering, i.e., the combination of ultraviolet (UV) exposure and water spraying, on the visual and mechanical properties of basalt fiber reinforced polymer (BFRP) composites. The solvent exchange method, sonication and high shear [...] Read more.
This work aims to give insight on the effect of accelerated weathering, i.e., the combination of ultraviolet (UV) exposure and water spraying, on the visual and mechanical properties of basalt fiber reinforced polymer (BFRP) composites. The solvent exchange method, sonication and high shear milling technique were used to prepare the nanocomposite laminates. Three types of laminates were fabricated, i.e., unmodified BFRP, nanosilica modified BFRP and graphene nanoplatelet (GNP) modified BFRP composites with the total fiber loading of 45 wt.%. Glass fiber reinforced polymer (GFRP) laminate was also prepared for performance comparison purposes between the natural and synthetic fibers. The laminates were exposed to UV with a total weathering condition of 504 h using a Quantum-UV accelerated weathering tester. The weathering condition cycle was set at 8 h 60 °C UV exposure and 4 h 50 °C condensation. The discoloration visual inspection on the tested specimen was observed under the optical microscope. The obtained results showed that the UV exposure and water absorption caused severe discoloration of the laminates due to photo-oxidation reaction. The effect of weathering conditions on tensile and flexural properties of unmodified BFRP composites indicated that the UV exposure and water absorption caused reduction by 12% in tensile strength and by 7% in flexural strength. It is also found that the reduction in tensile and flexural properties of nanomodified BFRP composites was smaller than the unmodified system. It concluded from this work, that the mineral based composites (i.e., BFRP) has high potential for structural applications owing to its better properties than synthetic based composites (i.e., GFRP). Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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19 pages, 10282 KiB  
Article
Key Role of the Dispersion of Carbon Nanotubes (CNTs) within Epoxy Networks on their Ability to Release
by Maxime Pras, Jean-François Gérard, Luana Golanski, Guilhem Quintard and Jannick Duchet-Rumeau
Polymers 2020, 12(11), 2530; https://doi.org/10.3390/polym12112530 - 29 Oct 2020
Cited by 14 | Viewed by 2834
Abstract
Carbon nanotube (CNT)-reinforced nanocomposites represent a unique opportunity in terms of designing advanced materials with mechanical reinforcement and improvements in the electrical and thermal conductivities. However, the toxic effects of these composites on human health have been studied, and very soon, some regulations [...] Read more.
Carbon nanotube (CNT)-reinforced nanocomposites represent a unique opportunity in terms of designing advanced materials with mechanical reinforcement and improvements in the electrical and thermal conductivities. However, the toxic effects of these composites on human health have been studied, and very soon, some regulations on CNTs and on composites based on CNTs will be enacted. That is why the release of CNTs during the nanocomposite lifecycle must be controlled. As the releasing depends on the interfacial strength that is stronger between CNTs and polymers compared to CNTs in a CNT agglomerate, two dispersion states—one poorly dispersed versus another well dispersed—are generated and finely described. So, the main aim of this study is to check if the CNT dispersion state has an influence on the CNT releasing potential in the nanocomposite. To well tailor and characterize the CNT dispersion state in the polymer matrix, electronic microscopies (SEM and TEM) and also rheological analysis are carried out to identify whether CNTs are isolated, in bundles, or in agglomerates. When the dispersion state is known and controlled, its influence on the polymerization kinetic and on mechanical properties is discussed. It appears clearly that in the case of a good dispersion state, strong interfaces are generated, linking the isolated nanotubes with the polymer, whereas the CNT cohesion in an agglomerate seems much more weak, and it does not provide any improvement to the polymer matrix. Raman spectroscopy is relevant to analyze the interfacial properties and allows the relationship with the releasing ability of nanocomposites; i.e., CNTs poorly dispersed in the matrix are more readily released when compared to well-dispersed nanocomposites. The tribological tests confirm from released particles granulometry and observations that a CNT dispersion state sufficiently achieved in the nanocomposite avoids single CNT releasing under those solicitations. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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23 pages, 6366 KiB  
Article
Mechanical and Functional Properties of Novel Biobased Poly(decylene-2,5-furanoate)/Carbon Nanotubes Nanocomposite Films
by Giulia Fredi, Andrea Dorigato, Mauro Bortolotti, Alessandro Pegoretti and Dimitrios N. Bikiaris
Polymers 2020, 12(11), 2459; https://doi.org/10.3390/polym12112459 - 23 Oct 2020
Cited by 15 | Viewed by 2783
Abstract
The present work investigates the microstructural, thermo-mechanical, and electrical properties of a promising, but still not thoroughly studied, biobased polymer, i.e., poly(decylene furanoate) (PDeF), and its performance when multi-walled carbon nanotubes (CNTs) are added. After sample preparation by solution mixing and film casting, [...] Read more.
The present work investigates the microstructural, thermo-mechanical, and electrical properties of a promising, but still not thoroughly studied, biobased polymer, i.e., poly(decylene furanoate) (PDeF), and its performance when multi-walled carbon nanotubes (CNTs) are added. After sample preparation by solution mixing and film casting, the microstructural investigation evidences that the fracture surface becomes smoother and more homogeneous with a small fraction of CNTs, and that the production process is suitable to achieve good disentanglement and dispersion of CNTs within the matrix, although some aggregates are still observable. CNTs act as nucleating agents for PDeF crystals, as evidenced by differential scanning calorimetry, as the crystallinity degree increases from 43.2% of neat PDeF to 55.0% with a CNT content of 2 phr, while the crystallization temperature increases from 68.4 °C of PDeF to 91.7 °C of PDeF-CNT-2. A similar trend in crystallinity is confirmed by X-ray diffraction, after detailed Rietveld analysis with a three-phase model. CNTs also remarkably improve the mechanical performance of the bioderived polymer, as the elastic modulus increases up to 123% and the stress at break up to 131%. The strain at break also increases by +71% when a small amount of 0.25 phr of CNTs are added, which is probably the consequence of a more homogeneous microstructure. The long-term mechanical performance is also improved upon CNT addition, as the creep compliance decreases considerably, which was observed for both the elastic and the viscoelastic component. Finally, the films become electrically dissipative for a CNT content of 1 phr and conductive for a CNT amount of 2 phr. This study contributes to highlight the properties of bioderived furan-based polymer PDeF and evidences the potential of CNTs as a promising nanofiller for this matrix. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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22 pages, 12372 KiB  
Article
Tribological Performance of Nylon Composites with Nanoadditives for Self-Lubrication Purposes
by Isabel Clavería, Sofía Gimeno, Ignacio Miguel, Gemma Mendoza, Aleida Lostalé, Ángel Fernández, Pere Castell and Daniel Elduque
Polymers 2020, 12(10), 2253; https://doi.org/10.3390/polym12102253 - 30 Sep 2020
Cited by 10 | Viewed by 3021
Abstract
A systematic study comparing the wear behaviour of composites with nylon matrix (PA66, PA46, PA12) and different nanoadditives and reinforcing additives (graphite, graphene, MoS2 and ZrO2) has been carried out in order to achieve a proper self-lubricant material for bearing [...] Read more.
A systematic study comparing the wear behaviour of composites with nylon matrix (PA66, PA46, PA12) and different nanoadditives and reinforcing additives (graphite, graphene, MoS2 and ZrO2) has been carried out in order to achieve a proper self-lubricant material for bearing cages. The wear characterisation was done using pin-on-disc tests, SEM and EDX analysis. The results show that better outcomes are obtained for composites based on PA12. The addition of ZrO2 offers negative values of wear due to the metallic particle transference from the counterface to the polymeric pin. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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15 pages, 6120 KiB  
Article
Surface Modification of Carbon Microspheres with Guanidine Phosphate and Its Application as a Flame Retardant in PET
by Shan Jiang, Cheng Ji, Dan Zha, Yonghong Ding, Dun Wu and Qiang Yu
Polymers 2020, 12(8), 1689; https://doi.org/10.3390/polym12081689 - 29 Jul 2020
Cited by 9 | Viewed by 2288
Abstract
Composites based on polyethylene terephthalate (PET) and surface-modified carbon microspheres (CMSs) were prepared by melt mixing. The surface modification of CMSs was conducted with low-temperature plasma technology first, and a phosphorus-nitrogen flame retardant, guanidine phosphate (GDP), was then grafted onto CMSs. The modification [...] Read more.
Composites based on polyethylene terephthalate (PET) and surface-modified carbon microspheres (CMSs) were prepared by melt mixing. The surface modification of CMSs was conducted with low-temperature plasma technology first, and a phosphorus-nitrogen flame retardant, guanidine phosphate (GDP), was then grafted onto CMSs. The modification of CMSs was done to improve both the filler dispersity in the PET matrix and the flame-retardant performance of composites. The obtained CMSs-GDP was characterized by FTIR spectra and a scanning electron microscope (SEM). The grafting ratio was characterized and calculated by thermal gravimetric analysis (TGA). The grain size analysis was used to describe the dispersity of CMSs. The mechanical properties of the PET/CMSs-GDP composite were measured using a universal testing machine. The PET/CMSs-GDP composite can achieve a limiting oxygen index (LOI) value of 32.4% and a vertical burning test (UL94) V-0 rating at 3% CMSs-GDP loading. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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12 pages, 3833 KiB  
Article
l-Arginine Grafted Poly(Glycerol Sebacate) Materials: An Antimicrobial Material for Wound Dressing
by Chia-Chun Wang, Ting-Yu Shih, Yi-Ting Hsieh, Jie-Len Huang and Jane Wang
Polymers 2020, 12(7), 1457; https://doi.org/10.3390/polym12071457 - 29 Jun 2020
Cited by 9 | Viewed by 3412
Abstract
This study focuses on the development and evaluation of a novel wound dressing material. l-arginine grafted poly(glycerol sebacate) materials (PGS-g-Arg) are developed by chemical conjugation of l-arginine on poly(glycerol sebacate) chains and the mechanical property, water vapor transmission rate, antimicrobial functions [...] Read more.
This study focuses on the development and evaluation of a novel wound dressing material. l-arginine grafted poly(glycerol sebacate) materials (PGS-g-Arg) are developed by chemical conjugation of l-arginine on poly(glycerol sebacate) chains and the mechanical property, water vapor transmission rate, antimicrobial functions and biocompatibility are investigated. At various l-arginine grafting ratio, the mechanical properties are tunable. It was found that between 7–13% l-arginine grafting ratios, the tensile strengths of PGS-g-Arg were similar to that of natural skin. These materials are shown with a low water vapor transmission rate, 6.1 to 10.3 g/m2/h, which may form a barrier and assist in the closure of wounds. Inhibition in the growth of Pseudomonas aeruginosa and Staphylococcus aureus was observed on PGS-g-Arg, and a series of experiments were conducted to confirm its biocompatibility. In summary, l -arginine grafted poly(glycerol sebacate) may offer a novel option for wound dressing. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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Review

Jump to: Research

18 pages, 1722 KiB  
Review
Polymer Nanocomposites for Photocatalytic Degradation and Photoinduced Utilizations of Azo-Dyes
by Emily Z. Wang, Yigui Wang and Dequan Xiao
Polymers 2021, 13(8), 1215; https://doi.org/10.3390/polym13081215 - 9 Apr 2021
Cited by 17 | Viewed by 3842
Abstract
Specially designed polymer nanocomposites can photo-catalytically degrade azo dyes in wastewater and textile effluents, among which TiO2-based nanocomposites are outstanding and extensively explored. Other nanocomposites based on natural polymers (i.e., chitosan and kaolin) and the oxides of Al, Au, B, Bi, [...] Read more.
Specially designed polymer nanocomposites can photo-catalytically degrade azo dyes in wastewater and textile effluents, among which TiO2-based nanocomposites are outstanding and extensively explored. Other nanocomposites based on natural polymers (i.e., chitosan and kaolin) and the oxides of Al, Au, B, Bi, Fe, Li, and Zr are commonly used. These nanocomposites have better photocatalytic efficiency than pure TiO2 through two considerations: (i) reducing the hole/electron recombination rate by stabilizing the excited electron in the conducting band, which can be achieved in TiO2-nanocomposites with graphene, graphene oxide, hexagonal boron nitride (h-BN), metal nanoparticles, or doping; (ii) decreasing the band energy of semiconductors by forming nanocomposites between TiO2 and other oxides or conducting polymers. Increasing the absorbance efficiency by forming special nanocomposites also increases photocatalytic performance. The photo-induced isomerization is exploited in biological systems, such as artificial muscles, and in technical fields such as memory storage and liquid crystal display. Heteroaryl azo dyes show remarkable shifts in photo-induced isomerization, which can be applied in biological and technical fields in place of azo dyes. The self-assembly methods can be employed to synthesize azo-dye polymer nanocomposites via three types of interactions: electrostatic interactions, London forces or dipole/dipole interactions between azo dyes, and photo alignments. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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35 pages, 6706 KiB  
Review
Recent Developments in Nanocellulose-Reinforced Rubber Matrix Composites: A Review
by Darren Yi Sern Low, Janarthanan Supramaniam, Apinan Soottitantawat, Tawatchai Charinpanitkul, Wiwut Tanthapanichakoon, Khang Wei Tan and Siah Ying Tang
Polymers 2021, 13(4), 550; https://doi.org/10.3390/polym13040550 - 12 Feb 2021
Cited by 44 | Viewed by 7611
Abstract
Research and development of nanocellulose and nanocellulose-reinforced composite materials have garnered substantial interest in recent years. This is greatly attributed to its unique functionalities and properties, such as being renewable, sustainable, possessing high mechanical strengths, having low weight and cost. This review aims [...] Read more.
Research and development of nanocellulose and nanocellulose-reinforced composite materials have garnered substantial interest in recent years. This is greatly attributed to its unique functionalities and properties, such as being renewable, sustainable, possessing high mechanical strengths, having low weight and cost. This review aims to highlight recent developments in incorporating nanocellulose into rubber matrices as a reinforcing filler material. It encompasses an introduction to natural and synthetic rubbers as a commodity at large and conventional fillers used today in rubber processing, such as carbon black and silica. Subsequently, different types of nanocellulose would be addressed, including its common sources, dimensions, and mechanical properties, followed by recent isolation techniques of nanocellulose from its resource and application in rubber reinforcement. The review also gathers recent studies and qualitative findings on the incorporation of a myriad of nanocellulose variants into various types of rubber matrices with the main goal of enhancing its mechanical integrity and potentially phasing out conventional rubber fillers. The mechanism of reinforcement and mechanical behaviors of these nanocomposites are highlighted. This article concludes with potential industrial applications of nanocellulose-reinforced rubber composites and the way forward with this technology. Full article
(This article belongs to the Special Issue Polymer Nanocomposites II)
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