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Advanced Polymer Composites: Structure-Property-Processing Relationships

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

Deadline for manuscript submissions: closed (5 December 2022) | Viewed by 34625

Special Issue Editor

Department of Textile System Engineering, Kyungpook National University, Daegue 41566, Korea
Interests: polymer chemistry, interface engineering
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Functional polymer composites are making significant strides in design, synthesis, processing, and promising applications. By using suitable fillers and matrices to create new and attractive properties, functional polymer composites can meet the most difficult standards of users, especially in high-tech industries. Functional polymer composites are crucial to the development of new cutting-edge technologies, especially in the fourth industrial revolution. From this point of view, the importance of a systematic understanding of the fundamental physical relationship between nanoscale structural variables and macroscopic properties of polymer composites is highlighted. Hence, structure–property–processing relationships are crucial for their future development as innovative advanced polymer composite systems. Advances in functional polymer composites will promote human welfare by creating new solutions and materials to overcome global energy and environmental crises.

This Special Issue will cover recent advances concerning structure, property, processing, as well as promising applications of advanced polymer composites. Submitted manuscripts will be fast-track reviewed. Research articles, review articles, perspectives, and communications and letters are also invited.

Dr. Ki-Ho Nam
Guest Editor

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Keywords

  • Design, synthesis, and analysis of polymer composites
  • Interfacial phenomena in polymer composites
  • Mathematical/physical modeling, computer simulation, and experimentation
  • Extrusion, molding, fiber spinning, printing, and other processing technologies
  • Applications of polymer composites in advanced industries

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Published Papers (13 papers)

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Research

13 pages, 4270 KiB  
Article
Impact of the Processing-Induced Orientation of Hexagonal Boron Nitride and Graphite on the Thermal Conductivity of Polyethylene Composites
by Mehamed Ali, Patrik Sobolciak, Igor Krupa and Ahmed Abdala
Polymers 2023, 15(16), 3426; https://doi.org/10.3390/polym15163426 - 16 Aug 2023
Cited by 2 | Viewed by 1241
Abstract
Emergent heat transfer and thermal management applications require polymer composites with enhanced thermal conductivity (κ). Composites filled with non-spherical fillers, such as hexagonal boron nitride (hBN) and Graphite (Gr), suffer from processing-induced filler orientations, resulting in anisotropic κ, commonly low in the through-plane [...] Read more.
Emergent heat transfer and thermal management applications require polymer composites with enhanced thermal conductivity (κ). Composites filled with non-spherical fillers, such as hexagonal boron nitride (hBN) and Graphite (Gr), suffer from processing-induced filler orientations, resulting in anisotropic κ, commonly low in the through-plane direction. Here, the effects of extrusion and compression molding-induced orientations on κ of hBN- and Gr-filled polyethylene composites were investigated. The effect of extrusion on the hBN orientation was studied using dies of various shapes. The shaped extrudates exhibited hBN orientations parallel to the extrusion flow direction, which prompted additional hBN orientation during compression molding. κ of the composites produced with shaped extrudates varied from 0.95 to 1.67 W m−1 K−1. Pelletizing and crushing the extrudates improved κ, by exploiting and eliminating the effect of extrusion-induced hBN orientations. Gr-filled composites showed better κ than hBN composites due to the higher intrinsic conductivity and bigger particle sizes. A maximum κ of 5.1 and 11.8 W m−1 K−1 was achieved in composites with oriented hBN and Gr through a thin rectangular die and stacking the sheets to fabricate composites with highly oriented fillers. Full article
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12 pages, 22877 KiB  
Article
Improving Dispersion of Carbon Nanotubes in Natural Rubber by Using Waterjet-Produced Rubber Powder as a Carrier
by Xiurui Guo, Shouyun Guo, Gongxu Liu, Lichen Bai, Haichao Liu, Yuan Xu, Jinyang Zhao, Hailin Chai, Xingao Jian, Lei Guo and Fumin Liu
Polymers 2023, 15(3), 477; https://doi.org/10.3390/polym15030477 - 17 Jan 2023
Cited by 3 | Viewed by 2079
Abstract
Carbon nanotube (CNT), as reinforcing agents in natural rubber (NR), has gained a large amount of consideration due to their excellent properties. Uniform dispersion of CNT is the key to obtaining high-performance NR nanocomposites. In this contribution, a novel ultrasonic grinding dispersion method [...] Read more.
Carbon nanotube (CNT), as reinforcing agents in natural rubber (NR), has gained a large amount of consideration due to their excellent properties. Uniform dispersion of CNT is the key to obtaining high-performance NR nanocomposites. In this contribution, a novel ultrasonic grinding dispersion method of CNT with waterjet-produced rubber powder (WPRP) as a carrier is proposed. Microscopic morphologies show that a Xanthium-like structure with WPRP as the core and CNTs as the spikes is formed, which significantly improves the dispersion of CNT in the NR matrix and simultaneously strengthens the bonding of the WPRP and NR matrix. With the increase in the WPRP loading, the Payne effect of CNT/WPRP/NR composites decreases, indicating the effectiveness of the dispersion method. The vulcanization MH and ML value and crosslinking density increase with the increase in the WPRP loading, whereas the scorch time and cure time exhibit a decreasing trend when the WPRP loading is less than 15 phr. It is found that the CNT/WPRP/NR composites filled with 5 phr WPRP have a 4% increase in 300% modulus, a 3% increase in tensile strength, while a 5% decrease in Akron abrasion loss, compared to CNT/NR composites. Full article
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12 pages, 1941 KiB  
Article
The Influence of Ply Stacking Sequence on Mechanical Properties of Carbon/Epoxy Composite Laminates
by Raphael Olabanji Ogunleye, Sona Rusnakova, Milan Zaludek and Samuel Emebu
Polymers 2022, 14(24), 5566; https://doi.org/10.3390/polym14245566 - 19 Dec 2022
Cited by 11 | Viewed by 3003
Abstract
In this work, the effect of ply stacking sequence of carbon/epoxy laminates subjected to flexural, tensile and impact loading was investigated. Five laminates with different stacking configurations were produced using the hand-laying-up technique. This includes a unidirectional laminate, cross-ply laminates, and quasi-isotropic laminates. [...] Read more.
In this work, the effect of ply stacking sequence of carbon/epoxy laminates subjected to flexural, tensile and impact loading was investigated. Five laminates with different stacking configurations were produced using the hand-laying-up technique. This includes a unidirectional laminate, cross-ply laminates, and quasi-isotropic laminates. Following the autoclave curing process, the responses of the composites to bending, tension and impact force were determined according to ASTM standards, and their corresponding strength, stiffness as well as impact energy were evaluated. Likewise, the flexural failure mode associated with each laminate was characterised using an optical microscope. The unidirectional laminates have higher flexural and tensile strength compared to the cross-ply and quasi-isotropic laminates. Moreover, as a result of material symmetry, the flexural and tensile modulus of symmetric cross-ply laminate improved by 59.5% and 3.97% compared to the unsymmetric counterpart. Furthermore, the quasi-isotropic laminates with absorption energy of 116.2 kJ/m2 and 115.12 kJ/m2, respectively have higher impact resistance compared to other samples. Full article
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19 pages, 22108 KiB  
Article
Features of Composite Layers Created Using an Aqueous Suspension of a Fluoropolymer
by Dmitriy Valerievich Mashtalyar, Konstantine Vakhtangovich Nadaraia, Evgeny Alekseevich Belov, Igor Mikhaylovich Imshinetskiy, Sergey Leonidovich Sinebrukhov and Sergey Vasilevich Gnedenkov
Polymers 2022, 14(21), 4667; https://doi.org/10.3390/polym14214667 - 1 Nov 2022
Cited by 17 | Viewed by 1806
Abstract
This paper presents a method for the formation of composite-polymer-containing coatings on MA8 Mg alloy by plasma electrolytic oxidation (PEO), followed by the deposition of a fluoropolymer from an aqueous suspension of superdispersed polytetrafluoroethylene. The Scanning Electron Microscope(SEM), Energy Dispersive Spectroscopy(EDS), and X-ray [...] Read more.
This paper presents a method for the formation of composite-polymer-containing coatings on MA8 Mg alloy by plasma electrolytic oxidation (PEO), followed by the deposition of a fluoropolymer from an aqueous suspension of superdispersed polytetrafluoroethylene. The Scanning Electron Microscope(SEM), Energy Dispersive Spectroscopy(EDS), and X-ray Diffraction(XRD) analyses established morphological features as well as elemental and phase composition of composite coatings. The fact that the pores are filled with a fluoropolymer has been experimentally confirmed. An assessment of the corrosion properties of formed composite coatings revealed a decrease in the corrosion current density by more than four orders of magnitude in comparison with the base PEO layer. The highest resistance to the damaging effects of a corrosive environment, according to the results of long-term exposure tests, was demonstrated by coatings after three treatments with polytetrafluoroethylene. The obtained polymer-containing coatings have antifriction properties, reducing the wear of the coatings by more than 27-fold in comparison with the base PEO layer. It was revealed that composite coatings have superhydrophobic properties: the value of the contact angle reaches 154°, and the hysteresis of the contact angle is less than 10°. Full article
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23 pages, 5301 KiB  
Article
Flexible Composite Films Made of EMAANa+ Ionomer: Evaluation of the Influence of Piezoelectric Particles on the Thermal and Mechanical Properties
by Sandra P. S. Tita, Fernão D. Magalhães, Diana Paiva, Maria A. Z. Bertochi, Guilhermina F. Teixeira, Ana L. Pires, André M. Pereira and José R. Tarpani
Polymers 2022, 14(13), 2755; https://doi.org/10.3390/polym14132755 - 5 Jul 2022
Cited by 2 | Viewed by 2335
Abstract
Studies that aim to produce flexible films of composite materials based on ionomers-PZT, and volume fractions lower than 10% PZT, in order to monitor damage in aeronautical structures are seldom investigated. The growing emphasis on the use of polymers capable of self-healing after [...] Read more.
Studies that aim to produce flexible films of composite materials based on ionomers-PZT, and volume fractions lower than 10% PZT, in order to monitor damage in aeronautical structures are seldom investigated. The growing emphasis on the use of polymers capable of self-healing after damage or activation by heating has motivated the application of self-healing ionomers as polymeric matrices in composites with piezoelectric particles aiming to monitor damage. Flexible composite films were developed based on the self-healing polymer matrix Surlyn® 8940 ionomer (DuPontTM—Wilmington, DE, USA) and PZT particles (connectivity 2–3) in volume fractions of 1, 3, 5 and 7%, with thickness around 50–100 µm. The choice of PZT volume fractions followed the preliminary requirement that establishes a final density, which is lower or at least close to the density of the materials used in aeronautical structures. Since the application of composites based on epoxy resin/carbon fibers has been increasing in the aeronautical segment, this material (with density lower than 1500 kg/m3) was chosen as a reference for the present work. Thus, due to self-healing (a characteristic of the matrix Surlyn® 8940) combined with recyclability, high flexibility and low thickness, the flexible composite films showed advantages to be applied on aeronautical structures, which present complex geometries and low-density materials. The manufactured films were characterized by SEM, XRD, DMA and mechanical tensile tests. The results were discussed mainly in terms of the volume fraction of PZT. X-ray diffraction patterns showed coexistent rhombohedral and tetragonal phases in the PZT particles-dispersed composite, which can potentialize the alignment of ferroelectric domains during polarization under strong electrical field, enhancing dielectric and piezoelectric properties toward sensing applications. DMA and tensile testing results demonstrated that the addition of PZT particles did not impair either dynamic or quasi-static mechanical performance of the flexible composite films. It was concluded that the PZT volume fraction should be lower than 3% because, for higher values, the molecular mobility of the polymer would suffer significant reductions. These findings, combined with the high flexibility and low density of the ceramic particle-filled thermoplastic polymer, render the developed flexible composite film a very promising candidate for strain and damage sensing in aeronautical structures. Full article
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22 pages, 5072 KiB  
Article
Influence of Ionomer and Cyanuric Acid on Antistatic, Mechanical, Thermal, and Rheological Properties of Extruded Carbon Nanotube (CNT)/Polyoxymethylene (POM) Nanocomposites
by Sang-Seok Yun, Dong-hyeok Shin and Keon-Soo Jang
Polymers 2022, 14(9), 1849; https://doi.org/10.3390/polym14091849 - 30 Apr 2022
Cited by 5 | Viewed by 2589
Abstract
The electrical properties of carbon-based filler-embedded polymer nanocomposites are essential for various applications such as antistatic and electromagnetic interference (EMI) applications. In this study, the impact of additives (i.e., ethylene-co-acid-co-sodium acid copolymer-based ionomer and cyanuric acid) on the antistatic, mechanical, thermal, and rheological [...] Read more.
The electrical properties of carbon-based filler-embedded polymer nanocomposites are essential for various applications such as antistatic and electromagnetic interference (EMI) applications. In this study, the impact of additives (i.e., ethylene-co-acid-co-sodium acid copolymer-based ionomer and cyanuric acid) on the antistatic, mechanical, thermal, and rheological properties of extruded multiwalled carbon nanotube (MWCNT)/polyoxymethylene (POM) nanocomposites were systematically investigated. The effects of each additive and the combination of additives were examined. Despite a slight reduction in mechanical properties, the incorporation of ionomer (coating on CNTs) and/or cyanuric acid (π-π interaction between CNTs and cyanuric acid) into the POM/CNT nanocomposites improved the CNT dispersity in the POM matrix, thereby enhancing electrical properties such as the electrical conductivity (and surface resistance) and electrical conductivity monodispersity. The optimum composition for the highest electrical properties was determined to be POM/1.5 wt% CNT/3.0 wt% ionomer/0.5 wt% cyanuric acid. The nanocomposites with tunable electrical properties are sought after, especially for antistatic and EMI applications such as electronic device-fixing jigs. Full article
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9 pages, 2991 KiB  
Article
Polymer Concentration and Liquid—Liquid Demixing Time Correlation with Porous Structure of Low Dielectric Polyimide in Diffusion-Driven Phase Separation
by Subin Kim, Jaemin Son, Hwon Park, Euigyung Jeong, Ki-Ho Nam and Jin-Seok Bae
Polymers 2022, 14(7), 1425; https://doi.org/10.3390/polym14071425 - 31 Mar 2022
Cited by 13 | Viewed by 3022
Abstract
Porous polyimide (PI) films are a promising low-k dielectric material for high-frequency data transmission with low signal attenuation. Pores are generated by non-solvent induced phase separation (NIPS) during phase inversion of polymer solution via non-solvent accumulation and solvent diffusion. In this study, aromatic [...] Read more.
Porous polyimide (PI) films are a promising low-k dielectric material for high-frequency data transmission with low signal attenuation. Pores are generated by non-solvent induced phase separation (NIPS) during phase inversion of polymer solution via non-solvent accumulation and solvent diffusion. In this study, aromatic PI was employed as a matrix for NIPS, and the influence of polymer concentration and liquid—liquid demixing time on the morphology of pores in the PI films was investigated. This ensured control over the porous structure of the PI film and provided desirable dielectric properties in a broad frequency range of 100 Hz–30 MHz (1.99 at 30 MHz) and thermal stability (Td5% > 576 °C, Tg > 391 °C). This study addresses the effect of polymer concentration and coagulation time on the morphology and physical properties of PI sponge films and provides guidance on the design and optimization of architectures for polymeric materials requiring pore modification. Full article
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18 pages, 4337 KiB  
Article
Exploration of the Adsorption Reduction of the Pigment Aggregates Strength under the Effect of Surfactants in Water-Dispersion Paints
by Antonina Dyuryagina, Aida Lutsenko, Kirill Ostrovnoy, Vitaliy Tyukanko, Alexandr Demyanenko and Meiramgul Akanova
Polymers 2022, 14(5), 996; https://doi.org/10.3390/polym14050996 - 28 Feb 2022
Cited by 9 | Viewed by 2879
Abstract
This article presents the results of studying the disaggregation of titanium dioxide in water-dispersion compositions based on an acrylic film-forming agent under the action of a surfactant. The possibility of using polyether siloxane copolymer (PC) and sodium polyacrylate (NaPA) in paint and varnish [...] Read more.
This article presents the results of studying the disaggregation of titanium dioxide in water-dispersion compositions based on an acrylic film-forming agent under the action of a surfactant. The possibility of using polyether siloxane copolymer (PC) and sodium polyacrylate (NaPA) in paint and varnish compositions as modifying additives of the dispersing effect is proved. The correlation between the dispersing effect of surfactants and the amount of their adsorption on the pigment is proved. NaPA, which provides a greater reduction in adsorption strength, demonstrates a greater dispersing effect than PC. It was found that the larger the size of the aggregates of pigment particles, the greater the disjoining pressure created by the surfactant. An equation is derived that generalizes the cumulative contribution of surfactant concentration and the content of the film-forming agent in suspensions to the average particle diameter of pigment. The introduction of NaPA in the amount of 0.25 g/dm3 into the paint allows the rate of acid corrosion to be reduced by 2 times, the number of pores in the coating to be decreased, and the adhesion of the coating to be significantly increased (by 2 points according to ISO 11845: 2020). Full article
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13 pages, 10570 KiB  
Article
Influence of Tire Rubber Particles Addition in Different Branching Degrees Polyethylene Matrix Composites on Physical and Structural Behavior
by Marc Marín-Genescà, Ramon Mujal Rosas, Jordi García Amorós, Lluis Massagues Vidal and Xavier Colom Fajula
Polymers 2021, 13(19), 3213; https://doi.org/10.3390/polym13193213 - 22 Sep 2021
Cited by 2 | Viewed by 1788
Abstract
Waste from pneumatic wheels is one of the major environmental problems, and the scientific community is looking for methods to recycle this type of waste. In this paper, ground tire rubber particles (GTR) from disused tires have been mixed with samples of low-density [...] Read more.
Waste from pneumatic wheels is one of the major environmental problems, and the scientific community is looking for methods to recycle this type of waste. In this paper, ground tire rubber particles (GTR) from disused tires have been mixed with samples of low-density polyethylene (LDPE) and high-density polyethylene (HDPE), and morphological tests have been performed using scanning electron microscopy (SEM), as well as the dynamic electric analysis (DEA) dielectric characterization technique using impedance spectroscopy. From this experience, how GTR reinforcement influences polyethylene and what influence GTR particles have on the branched polyethylene has been detected. For pure LDPE samples, a Debye-type dielectric behavior is observed with an imperfect semicircle, which depends on the temperature, as it shows differences for the samples at 30 °C and 120 °C, unlike the HDPE samples, which do not show such a trend. The behavior in samples with Debye behavior is like an almost perfect dipole and is due to the crystalline behavior of polyethylene at high temperature and without any reinforcement. These have been obtained evidence that for branched PE (LPDE) the Maxwell Wagner Sillars (MWS) effect is highly remarkable and that this happens due to the intrachain polarization effect combined with MWS. This means that the permittivity and conductivity at LDPE/50%GTR are high than LDPE/70%GTR. However, it does not always occur that way with HDPE composites in which HDPE/70%GTR has the highest values of permittivity and conductivity, due to the presence of conductive fraction (Carbon Black-30%) in the GTR particles and their dielectric behavior. Full article
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19 pages, 6273 KiB  
Article
Experimental and Numerical Study on the Compressive Failure of Composite Laminates with Fiber Waviness Defects
by Yuequan Wang, Shuhua Zhu, Hongshuang Li, Long Zhou and Wentao Yi
Polymers 2021, 13(19), 3204; https://doi.org/10.3390/polym13193204 - 22 Sep 2021
Cited by 4 | Viewed by 3360
Abstract
Fiber waviness defects are found in the inner surface of the hat-shaped stringers manufactured by a process system. In order to establish the acceptance criterion for the stringers with the fiber waviness defects, experimental testing and numerical simulation were carried out in this [...] Read more.
Fiber waviness defects are found in the inner surface of the hat-shaped stringers manufactured by a process system. In order to establish the acceptance criterion for the stringers with the fiber waviness defects, experimental testing and numerical simulation were carried out in this study. Specially induced fiber waviness defects of four pre-defined severity levels were manufactured and tested. A maximum of a 58.1% drop in compressive failure load is observed for the most severe level in the experimental results. A finite element model with progressive damage method and cohesive zone technique was developed to simulate the failure process and the impact of fiber waviness defects. The numerical simulation results of compressive failure load have a good agreement with experimental results qualitatively and quantitatively. In addition, two simple parameters, i.e., aspect ratio A/H and the number of plies with fiber waviness, are proposed to characterize the influence of the fiber waviness on the compressive failure load for the purpose of fast engineering quality checks. Full article
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19 pages, 9642 KiB  
Article
Preparation and Performance of Thermochromic and Self-Repairing Dual Function Paint Film with Lac Resin Microcapsules and Fluorane Microcapsules
by Xiaoxing Yan, Wenting Zhao and Lin Wang
Polymers 2021, 13(18), 3109; https://doi.org/10.3390/polym13183109 - 15 Sep 2021
Cited by 15 | Viewed by 2405
Abstract
Microcapsules with lac resin as the core material and urea-formaldehyde resin as the wall material were prepared by in situ polymerization, and then the lac resin microcapsules and fluorane microcapsules were added into a water-based primer or topcoat, respectively, to prepare water-based coatings [...] Read more.
Microcapsules with lac resin as the core material and urea-formaldehyde resin as the wall material were prepared by in situ polymerization, and then the lac resin microcapsules and fluorane microcapsules were added into a water-based primer or topcoat, respectively, to prepare water-based coatings with dual functions of thermochromic and self-repair. The effects of different methods of adding microcapsules on the optical properties, mechanical properties, self-repairing properties, and the aging resistance of water-based paint film were investigated, so as to prepare water-based paint film with the best discoloration and self-repairing functions. The results showed that the paint film with 10.0% fluorane microcapsules in the topcoat and 5.0% lac resin microcapsules in the primer had better comprehensive properties, and the paint film changed from yellow to colorless at 32 °C, with a color difference of 68.9, hardness of 3H, adhesion grade of 0, impact resistance of 13.0 kg∙cm, and elongation at break of 20.0%. The resistance of the paint film to NaCl, ethanol, and detergent was grade 2, with slight discontinuous marks, and the resistance to red ink was grade 3, with slight marks. The lac resin microcapsules have good aging resistance, which can enhance the aging resistance of the paint film with fluorane microcapsules. The gap width of the paint film was repaired by 2.1 µm, the self-repairing rate was 12.3%, and the paint film with lac resin microcapsules had a better crack inhibition effect. The results have provided a reference for multifunctional wood coatings. Full article
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16 pages, 4805 KiB  
Article
The Effect of Dialkyl Peroxide Crosslinking on the Properties of LLDPE and UHMWPE
by Pollyana S. M. Cardoso, Marcelo M. Ueki, Josiane D. V. Barbosa, Fabio C. Garcia Filho, Benjamin S. Lazarus and Joyce B. Azevedo
Polymers 2021, 13(18), 3062; https://doi.org/10.3390/polym13183062 - 10 Sep 2021
Cited by 10 | Viewed by 2771
Abstract
Peroxide has been considered a chemical agent that can be used to tune the properties of polymeric materials. This research evaluated the influence of different concentrations of dialkyl peroxides on the mechanical, thermal, and morphological properties of linear low-density polyethylene (LLDPE) and ultra-high [...] Read more.
Peroxide has been considered a chemical agent that can be used to tune the properties of polymeric materials. This research evaluated the influence of different concentrations of dialkyl peroxides on the mechanical, thermal, and morphological properties of linear low-density polyethylene (LLDPE) and ultra-high molecular weight polyethylene (UHMWPE). The neat polymer, as well as those with the addition of 1% and 2% by mass of dialkyl peroxides, were subjected to compression molding and immersion in water for 1 h, under controlled temperatures of 90 °C. The values of the gel content found in the samples indicated that the addition of peroxide to the LLDPE and to the UHMWPE promoted the formation of a reticulated network. The structure obtained by the crosslinking led to less reorganization of the chains during the crystallization process, resulting in the formation of imperfect crystals and, consequently, in the reduction in melting temperatures, crystallization and enthalpy. The mechanical properties were altered with the presence of the crosslinker. The polymers presented had predominant characteristics of a ductile material, with the occurrence of crazing with an increased peroxide content. Full article
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14 pages, 2495 KiB  
Article
Chemical Modifications of Continuous Aramid Fiber for Wood Flour/High-Density-Polyethylene Composites with Improved Interfacial Bonding
by Wanyu Liu, Yue Li, Shunmin Yi, Limin Wang, Haigang Wang and Jingfa Zhang
Polymers 2021, 13(2), 236; https://doi.org/10.3390/polym13020236 - 12 Jan 2021
Cited by 6 | Viewed by 2516
Abstract
To expand the use of wood plastic composites in the structural and engineering constructions applications, continuous aramid fiber (CAF) with nondestructive modification was incorporated as reinforcement material into wood-flour and high-density-polyethylene composites (WPC) by extrusion method with a special die. CAF was treated [...] Read more.
To expand the use of wood plastic composites in the structural and engineering constructions applications, continuous aramid fiber (CAF) with nondestructive modification was incorporated as reinforcement material into wood-flour and high-density-polyethylene composites (WPC) by extrusion method with a special die. CAF was treated with dopamine (DPA), vinyl triethoxysilane (VTES), and DPA/VTES, respectively. The effects of these modifications on compatibility between CAF and WPCs and the properties of the resulting composites were explored. The results showed that compared with the original CAF, the adhesion strength of DPA and VTES combined modified CAF and WPCs increased by 143%. Meanwhile, compared with pure WPCs, CAF after modification increased the tensile strength, tensile modulus, and impact strength of the resulting composites by 198, 92, and 283%, respectively. Full article
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