Flaky Graphite Research Articles

Microstructural evolution and mechanical properties of aluminum-graphite composites processed via accumulative roll bonding

In the present work, the aluminum-graphite metal matrix composites were fabricated via accumulative roll bonding (ARB). The graphite powder particles of <50 μm were introduced into aluminum in three different weight percentages. The effect of graphite on the evolution of microstructure, interface formation, and mechanical properties was studied. The microstructural investigation revealed that the amount of graphite played a vital role. A better particle distribution was observed for 1.25 and 1.5 wt%. However, a further increase in the reinforcement to 2.2 wt% shows longer flaky graphite with comparatively sharing a larger interface area with the matrix aluminum. An FE-SEM/EDS (Field Emission-Scanning electron microscopy/Energy dispersive Spectroscopy) line mapping at the aluminum-graphite interface confirmed an intact sound interface with better adherence properties. The ultimate tensile strength of the composites drastically improved with an increasing number of ARB passes. The FE-SEM taken over the fractured surface of the composite revealed that the ARBed Al-1100 and the composites failed in ductile mode. It was observed that the graphite particle was the primary source of nucleation in the composites. The voids have nucleated at the particle-matrix interface, followed by their growth and coalescence.

A New Insight into the Genesis of Graphite Deposits in Madagascar Using U–Pb Zircon Dating and Electron Microprobe Analysis

Madagascar is globally recognized as an important producer of high-quality flaky graphite. However, current research on graphite deposits in Madagascar remains insufficient. Previous studies have linked the genesis of Madagascan graphite deposits to the metamorphism of sedimentary organic matter. Here, we provide a case study of graphite deposits in Madagascar, combining new data from the Ambahita graphite deposit (AMG) in southern Madagascar with data from the Antanisoa graphite deposit (ANG) in central Madagascar and the Vohitasara graphite deposit (VOG) on the east coast of Madagascar. We note that the mineral assemblages of graphite-bearing rocks in the AMG, ANG, and VOG are not typical of metamorphic mineral assemblages but rather the results of filling and metasomatism by mantle-derived fluids that occurred after peak metamorphism. Electron microprobe analysis indicates that the graphite of the AMG, VOG, and ANG is usually associated with phlogopite or Mg-biotite; the phlogopite shares a common genesis with other widespread phlogopite deposits across Madagascar. We reveal that the distribution of graphite deposits in Madagascar is primarily controlled by ductile shear zones between blocks. Ductile shear zones that extend deep into the mantle can provide an ideal migration channel and architecture for the emplacement of mantle-derived fluids. The graphite mineralization formed no earlier than the peak metamorphism (490 Ma) and no later than the intrusion of pegmatite veins (389 ± 5 Ma). The distribution of graphite deposits, graphite orebody morphologies, mineral associations, and geochemical data suggest that the genesis of graphite deposits in Madagascar is linked to mantle-derived fluid filling rather than the metamorphism of sediments, as previously suggested. These findings have important implications for similar deposits in Madagascar and potentially globally.

Preparation of expandable flake-graphites with different particle sizes and their flame-retardant application for polypropylene

Bisulfate intercalated graphites with different particle sizes were prepared by a chemically oxidative method using natural flaky graphites as raw materials. The morphology and structure of the expandable graphites were confirmed by Fourier transform infrared spectroscopy, X-ray diffraction patterns, and scanning electron microscope. The effect of the particle size on the expanded volume was also investigated. Expandable graphite with +100 mesh particle size (EG100) showed the highest expanded volume of 225 mL/g. Moreover, a combination of expandable graphite, red phosphorus (RP), and melamine cyanurate (MC) into a polypropylene (PP) matrix exhibited a synergistic flame retardant effect. The composite loading EG100, RP, and MC with a mass ratio of 1:1:1 and a total filler content of 18 wt.% achieved a UL94 V-0 rating and a limiting oxygen index (LOI) of 28.9 %. The effect of particle size of expandable graphite on the mechanical properties was also evaluated.

Dielectric properties of epoxy/graphite flakes composites: Influence of loading and surface treatment

AbstractEpoxy‐rich carbon‐based composites are well recognized materials in industries owing to their good mechanical properties and thermal stability. Here, dielectric properties of composites based on bisphenol‐A‐epoxy resin loaded with 5, 6, 10, and 15 wt% of graphite flakes (GF) have been studied. The frequency and temperature dependence of the dielectric permittivity, dielectric loss, and ac conductivity have been examined in temperature (−103 to 97°C) and frequency (20 Hz–200 kHz) range. Influence of the filler surface chemistry have been studied for composites loaded with 5 wt% GF obtained: (i) under wet milling, without or with adding Triton‐100x as a surfactant, or (ii) under dry milling in the presence of KOH. The composite made of epoxy loaded with 5 wt% exfoliated expanded graphite flakes (EEG), was also prepared. The surface treatment with KOH notably increased dielectric constant of the composite, keeping low dielectric loss, while treatment with Triton‐100x significantly increased tanδ. The composite loaded with exfoliated expanded graphite shows higher ac conductivity than those obtained with flaky graphite, GF. Possibility to change dielectric properties of the composites without changing the loading content can be used as an approach in tailoring one with desired dielectric properties.

Aramid nanofiber assisted preparation of 3D-oriented graphite/silicone composite slices with high through-plane thermal conductivity and efficient electromagnetic interference shielding

High-performance electromagnetic interference (EMI) shielding materials with outstanding thermal transfer ability are urgently needed for modern electronics. Here, efficient 3D-oriented graphite/silicone EMI shielding composite slices with high through-plane thermal conductivity were prepared through the construction of 3D-oriented graphite skeletons followed by incorporation of silicone and cutting. The flaky graphite was utilized as functional fillers, and an ultra-low addition of aramid nanofibers (ANFs) was conducted to construct the supporting frameworks to maintain the structure of 3D-oriented graphite skeletons. The strategy of constructing of 3D-oriented graphite skeletons before incorporating of silicone facilitated the forming of efficient electrically conductive network and thermal transfer pathway in the prepared composite slices. The differences in thermal, electrical and EMI shielding properties that originated from the orientation of interconnected flaky graphite were systematically studied. As a result, the composite slices show significant enhancements of EMI SE of 65.28 dB in X-band, 76.62 dB in Ka-band and through-plane thermal conductivity of 10.53 W m−1 K−1 at the graphite fraction of 32.68 vol%. Additionally, the composite slices exhibit a good near-field (NF) shielding performance at the frequency range of 1–9 GHz. The composite slices reveal substantial potential for advanced EMI shielding and thermal management applications.

Preparation and electrochemical performance of FG/SnS2 composite as a cathode material for high power thermal batteries

SnS2 is a promising cathode material for its high specific capacity (1232 mAh/g), but it’s limited to the low decomposition temperature and conductivity as the thermal battery application. Herein, the flaky graphite(FG) coating SnS2 composite (denoted as FG/SnS2) with excellent thermal stability and conductivity was prepared. Then, as a thermal battery cathode material, it presented longer working time at current constant density of 100 mA/cm2, and higher pulse voltage at 2A/cm2 pulse current density than the pure SnS2. Application as the engineering unit thermal battery, its performance of higher working voltage, lower total resistance, and more stable output capacity indicated it can be used for high-power thermal batteries.

Compare graphite flotation and coal flotation in Reflux Flotation Cell

The Reflux Flotation Cell (RFC) has been developed as a game-changing technology to improve fine particle flotation, coarse particle flotation and plant capacity. It has been proved successful for coal flotation. This study compared graphite flotation and coal flotation in the RFC under the operation conditions established for optimizing coal flotation with an objective of extending the RFC to mineral flotation. It was interesting to find that graphite flotation in the RFC produced much lower combustible recovery than coal flotation especially at a high gas flux despite the same surface property and feed size of graphite and coal particles tested. Through the modelling of fluid flow, it was found that the lower combustible recovery from graphite flotation was due to the lower sphericity of graphite particles. The flaky graphite particles promoted a greater dynamic drag force and a greater particle settling velocity compared to coal particles with a greater sphericity. This increased the relative velocity between particles and bubbles in the RFC downcomer, unfavourable for bubble-particle attachment in graphite flotation in the RFC. In addition, a higher gas flux environment in the RFC downcomer produced a higher bubble slip velocity, further increasing the relative velocity between particles and bubbles, exacerbating graphite flotation. Furthermore, the extra gas in the inclined channels pushed more graphite particles to the tailing stream given the higher particle settling velocity. This study indicates a direction of how to optimize graphite flotation in the RFC.

Electrothermal/photothermal superhydrophobic coatings based on micro/nano graphite flakes for efficient anti-icing and de-icing

Currently, a series of anti/de-icing coatings that combine active and passive methods can take advantage of various energy sources to significantly improve anti/de-icing efficiency. However, the preparation of multifunctional coatings often relies on complex preparation techniques, expensive raw materials and additional control systems, which limit the practical application of such ice mitigation strategies. This study combined active and passive ice mitigation methods to construct an electrothermal/photothermal superhydrophobic coating. According to the laminar distribution of graphite molecules, micro/nano-scale flaky graphite particles are produced by a convenient mechanical wiping method, which provide the coating with superhydrophobicity, electrothermal and photothermal properties at the same time through a strong binding effect with PDMS. The dynamic, static anti/de-icing performances and the reliability of the electrical/photothermal properties of the coating are experimentally verified. This multifunctional ice mitigation strategy avoids complex control systems and cumbersome preparation processes, providing a new and viable path to effective anti/de-icing.

Enhanced microwave absorption properties of Ni decorated flaky graphite powders with frequency selective surfaces incorporation

Reasonable design of composition and structure is an effective way to improve microwave absorption performance of absorber. In this study, flaky Ni@Graphite composite powders containing various Ni contents were successfully fabricated through a facile electroless plating process. The phase compositions and microstructure of the composite powders were characterized. XRD and SEM results showed that the Ni particles are successfully reduced from the solution and anchored on the flaky Graphite. The electromagnetic and microwave absorption properties of the Ni@Graphite composite powders were also studied. The results illustrated that although the composite powders with 45 % Ni owned the minimum reflection loss (RLmin) of −18 dB, the maximum effective absorption bandwidth (EABmax) was only 1.1 GHz for the sample with 2.0 mm thickness. So periodic frequency selective surfaces (FSS) were designed to further improve the microwave absorption performance. As the structural parameters of the FSS were C= 14 mm, T1 = 1.78 mm, e= 1.18 mm, R= 1.86 mm and a= 1.6 mm, the optimized RLmin and EABmax of the Ni@Graphite powders were −19.27 dB and 3.2 GHz, respectively. It was worth noting that the strategy of balancing the electromagnetic properties of dual-loss composites by controlling the composition and structure can effectively improve microwave absorption performance. This work contributes to the development of high-performance Ni@Graphite microwave absorption materials.

Enhanced thermal conductivity of plasticized polyvinyl chloride composites based on 2D structural regulation of flaky graphite

With the rapid growth of the demand for heat dissipation in electronic devices, polymer-based composites with high thermal conductivity and excellent thermostability play a key role. Building an effective heat conduction path through precise structural regulation of thermally conductive composites is a simple and reliable solution. In this work, the factors affecting the thermal conductivity of plasticized polyvinyl chloride (PPVC)/graphite composites are analyzed from aspects of geometry dimension, carbon content, and structural regulation of graphite. By comparing the oriented and unoriented composites, the orientation of graphite can significantly improve the in-plane thermal conductivity of the composites. The in-plane and through-plane thermal conductivity of oriented PPVC/graphite composites with graphite thickness of 0.12 μm and carbon content of 99.06 % are 4.63 and 1.87 W·m−1·K−1, respectively. The anisotropic composite model filled with oriented two-dimensional filler is modeled and simulated by finite element method, and the experimental results are verified theoretically.

Graphite microcrystals growth in naturally graphitized coal from Hunan, China

The transformation of coal to graphite is a process through which carbon atoms are arranged from amorphous into a crystalline form. However, there is still no study focusing on how the graphite single crystal grow up in graphitized coals during natural graphitization. Herein, a series of naturally graphitized coals were thoroughly studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) to uncover the morphological and atomic structural evolution from anthracite to coaly graphite. The anthracite and meta-anthracite samples showed an amorphous carbon structure, whereas the carbon arrangement becomes more and more orderly from semi-graphite to coaly graphite as confirmed by XRD. The crushed particles of anthracite and meta-anthracite show granular and tabular texture with uneven surface under SEM. Small layered graphite flake appears from semi-graphite stage with co-occurrence of dense coal particles, HRTEM data shows the layered graphite flakes are the single graphite crystals. Almost all the dense coal particles change into layered microcrystalline graphite in the most graphitized coals (coaly graphite), and the flaky graphite microcrystals always show up as aggregates. The results will benefit the future applications of the naturally graphitized coals.

Methanol electrooxidation at NiCl2–FeCl3–graphite intercalation compound affected by ozone treatment

A graphite intercalation compound (GIC) incorporating nickel(II) and iron(III) chlorides (NiCl2–FeCl3–GIC) has been prepared, and the effect of ozone treatment on its catalytic activity towards methanol electrooxidation has been examined. The NiCl2–FeCl3–GIC was synthesized by a molten salt method, combining purified flaky graphite with the anhydrous metal chlorides. The obtained product was then modified with gaseous ozone. The crystalline structures and morphologies of the investigated compounds have been characterized by XRD and SEM/TEM techniques, respectively, and the results of these analyses have shown that ozone treatment of NiCl2–FeCl3–GIC contributes to changes in its structure and morphology. The process of methanol oxidation at both original and ozone-modified NiCl2–FeCl3–GIC electrodes has been examined in an alkaline electrolyte by means of cyclic voltammetry and a potentiostatic method. Electrochemical results have revealed that NiCl2–FeCl3–GIC exhibits activity towards the process of methanol electrooxidation. Furthermore, it has been proved that the electroactivity and durability of NiCl2–FeCl3–GIC are significantly increased following its ozone modification.

Study on purification of flaky graphite by argon arc plasma torch

High purity graphite with purity above 99.9%, as an industrial raw material, plays an important role in the high-tech field. The existing physical and chemical methods of graphite purification technology has high cost serious damage to equipment and environment by acid and alkali, and complex processes. Thus the development of an excellent and effective graphite purification technology has become a research hotspot in recent years at home and abroad. A purification method of flaky graphite by arc plasma is established in this paper. The characteristics of high temperature which can be produced quickly by using arc plasma is used to treat the flaky graphite samples with a purity of 94.18% from Jixi City of Heilongjiang Province, under high temperature. The results show that the optimal discharge parameters are air flow rate 25 L/min, current 400 A and power 10 kW. At this point, the surface temperature of the arc plasma is up to 3350 ℃. Scanning electron microscope is used to compare the microstructure of graphite samples before and after arc processing to find the characteristics of shredding and breaking of graphite samples. The graphite purity and impurities are analysed according to national standard chemical analysis method of GB/T 3521 2008. After arc treatment, the purity of graphite is increased to 99.21%.

Microstructural, mechanical and tribological performances of copper foam modified CFRP composite for pantograph strip

AbstractA novel pantograph strip of copper mesh modified carbon fiber reinforced polymer (CFRP) composite was fabricated by impregnating copper foam with the resin mixture of carbon fiber and flaky graphite, following by mold hot‐pressing technology. Microstructure, mechanical strength, electric conductivity, friction, and wear behaviors of the composite were investigated and analyzed to explore the fracture failure and wear mechanisms. The results show that the composite obtains much lower electric resistance than that of the pure carbon strip used in China's high‐speed railway. Adding carbon fiber can improve impact strength and wear resistance considerably, but has little effect on anti‐friction performance. The electric resistance and tribological performances are graphite dependent, reduced electric resistance and friction coefficient can be obtained with the increase of flaky graphite from 0 to 15 wt% while negligible changes of impact strength and wear rate are found. However, further increasing the flaky graphite to 20 wt%, the wear rate reveals a dramatic rise. High content of flaky graphite contributes to the formation of thick tribolayer with unconsolidated structure. And the tribolayer is easy to curl and worn off from the wear surface, leading to severe wear of the composite during the current carrying friction tests.

Electromagnetic properties of Carbon-Graphene Xerogel, Graphite and Ni-Zn Ferrite composites in polystyrene matrix in the X-Band (8.2 – 12.4 GHz)

The electromagnetic properties of Carbon-Graphene Xerogel (CGX), Flaky graphite (GR) and Nickel-Zinc ferrite (FeNiZn) composites in polystyrene (PS) matrix were studied in the X-Band range (8.2 – 12.4 GHz). In this work the Expanded Polystyrene (EPS) waste material was processed into polystyrene through the recycling of EPS. The polystyrene obtained was utilized as dielectric matrix, mainly because PS is a well-known organic polymer that presents low dielectric loss and light weight, which contribute to applications in composites for the aerospace field. In order to produce the final composite specimens, the CGX additive was previously synthesized through a sustainable method that employed the use of waste from the paper and pulp industry (black liquor). Afterwards, the morphological and structural analysis were made through Scanning Electron Microscope (SEM) and Raman Spectrometer, respectively. On the other hand, the magnetic ferrite material, FeNiZn, was obtained for the composite production through calcination, whereas the GR utilized was commercially obtained. It was observed that the increase of CGX and GR influenced on the increase of the Complex Permittivity, and that 10 wt% CGX + 50wt% FeNiZn composite sample demonstrated an absorption peak at 10.5 GHz. The results are relevant concerning the recycling of EPS waste through its use as dielectric matrix, thus developing greener and low-weight composite materials to be used in microwave applications.

The preparation of graphite/silicon@carbon composites for lithium-ion batteries through molten salts electrolysis

High-specific-capacity materials are crucial for the high-energy-density lithium-ion secondary batteries as the automakers and customers are both eager to extend the cruising range of electric vehicles. The current commercial silicon/carbon composites are based on the mechanical mixture of silicon and graphite, but this weak combination is not suitable for the higher-capacity materials. Here, low-cost raw materials are used for the preparation of a graphite/silicon@carbon composite negative electrode material, which synergizes ball milling, molten salts electrolysis and carbon coating. Silica is in situ electrochemically reduced to silicon on the flaky graphite serving as the conducting substrate during the electrolysis process. It is found that ball milling increases the active sites on the basal plane of graphite, which is beneficial for the nucleation and growth of the silicon, and enhances the bonding of silicon particles and graphite. As for the electrochemical results of coin-type cells, this graphite/silicon@carbon composite material exhibits a better cycle performance than the commercial Si/C 650 silicon-based composite material.

Fabrication of highly conducting nickel-coated graphite composite particles with low Ni content for excellent electromagnetic properties

Nickel-coated flaky graphite particles (FGP@NiCPs) have been widely employed as key fillers of electromagnetic functional composites. However, the existing such fillers suffer from disadvantages of uncompacted shells, unsatisfactory conductivity or high nickel content, making it hard to meet high requirements for electronic connection and electromagnetic compatibility. Herein, we have demonstrated an efficient approach to achieving sufficiently heterogeneous nucleation coupled with electroless Ni plating to fabricate highly conducting FGP@NiCPs with low Ni content for excellent electromagnetic properties of polymer-matrix composites. Preparation of the typical FGP@NiCPs consists of rinsing flaky graphite particles (FGPs), adsorbing nickel ions, in-situ reduction into nickel nuclei and electroless Ni plating. On the one side, the hydrophilicity of FGPs can be improved by soxhlet extraction. This is one of important factors to adsorb more nickel ions on FGPs because they can be uniformly dispersed or fully exposed to NiSO 4 solution. On the other side, the rinsed FGPs are immersed into a high concentration ([NiSO 4 ]) solution, which facilitates to further adsorb enough nickel ions through electrostatic attraction. Subsequently, these nickel ions adsorbed on FGPs are in-situ reduced into a lot of nickel nuclei, indicating that increasing hydrophilicity and immersing into a high [NiSO 4 ] for FGPs synergistically favor heterogeneous nucleation burst. Finally, low content nickel densely-coated FGPs composite particles are successfully synthesized by controllable electroless Ni plating. As-obtained FGP@NiCPs exhibit dense shells, low Ni content and excellent electrical conductivity compared to the commercial FGP@NiCPs (CFGP@NiCPs). Furthermore, shielding effectiveness of composites containing the typical FGP@NiCPs is between 28.0 and 35.2 dB with frequency of electromagnetic wave ranging from 30 to 1500 MHz, and stronger than that of composites containing CFGP@NiCPs, owing to the relatively high electrical conductivity. Consequently, this work holds a promising potential for electromagnetic functional polymer-matrix composites. Increasing hydrophilicity and immersion into a high concentration of NiSO 4 solution for FGPs synergistically favor nucleation burst, which is advantageous to fabricate low content Ni densely-coated FGPs composite particles for excellent electromagnetic properties of their polymer-matrix composites. • Hydrophilicity of flaky graphite particles (FGPs) can be improved by soxhlet extraction. • Increasing hydrophilicity and immersion into a high concentration of NiSO 4 solution for flaky graphite particles (FGPs) favor nucleation burst. • Sufficient heterogeneous nucleation facilitates to fabricate low content Ni densely-coated FGPs with high conductivity. • As-obtained composite particles promise important applications in electronic connection and electromagnetic compatibility.

Dielectric properties and electromagnetic interference shielding effectiveness of Al2O3-based composites filled with FeSiAl and flaky graphite

Al2O3-based composites filled with FeSiAl and flaky graphite (FG) were prepared by hot-pressed sintering. The dielectric properties and electromagnetic interference shielding effectiveness were investigated. As the mass ratio of FeSiAl to FG decreases from 4:1 to 0:5, the real (ε′) and imaginary (ε″) parts of complex permittivity increase significantly. The increased ε′ values are ascribed to the enhancement of interfacial polarization and electronic polarization, and the elevated conductance loss and relaxation loss lead to the increased ε″ values. Due to the formation of conductive network and the increasing electrical conductivity, the electromagnetic shielding effectiveness is significantly improved with increasing the percentage of flaky graphite, and absorption plays a dominant role in the electromagnetic interference shielding mechanisms. The FeSiAl/FG-filled Al2O3 composite with the ratio of FeSiAl to FG 0:5 exhibits the maximum shielding effectiveness of 30.4 dB in the X-band, denoting the composites have wide potential application for large scale in military and commercial fields.

Effect of flaky graphite with different particle sizes on flame resistance of intumescent flame retardant coating

The effect of particle size of flaky graphite (FG) on the flame resistance of intumescent flame retardant (IFR) coatings (polyester resin-ammonium polyphosphate-urea-pentaerythrite) is preliminarily studied by cone calorimeter (CC), XRD, and SEM, to seek appropriate FG in facilely preparing FG-containing IFR coatings. The results of CC determine that the doped FG1500 (with an average particle size of 1500 mesh) constitutes the highest flame-retarding efficiency, evidenced by the lowest peak heat release rate (p-HRR) of 23.5 ​kW ​m−2 at 409 ​s and the fire growth index (FGI) of 0.06 ​kW ​m−2 ​s−1, due to the formation of continuously laminar char residue. However, the finer FG particle (with average particle size less than 3000 mesh) exerts adverse fireproof property, evidenced by the loose and porous char residue, leading to the highest FGI of 0.25 ​kW ​m−2 ​s−1 for FG-containing sample S12000 with an average particle size of 12,000 mesh. It clarifies that the FG with an appropriate particle size is definitely conducive to improving the flame resistance of IFR coating, elucidates that the competition between candlewick effect and physical barrier predominates the flame-retarding mechanism of FG-containing IFR coating. It promotes the benign design of organic-inorganic hybrid IFR coatings.

Spherical filler‐promoting thermally conductive pathway in graphite‐containing polymer composites for high heat radiation

ABSTRACTGraphite is an efficient and affordable filler for polymer composites, allowing the control of thermal conductivity. In comparison to other thermally conductive fillers, graphite is lightweight and flexible but affords anisotropic thermal conductivity. Herein, the control of thermal conductivity of graphite‐containing polymer composite sheet using spherical polymer particles as additional fillers is described. The thermal conductivity in the through‐plane direction (λt) of the composite sheet is enhanced by varying the composition ratio of the two fillers (flaky graphite and spherical particles), and optimizing the forming temperature and pressure. Graphite‐containing (25 wt%) polymer composite sheet formed by compression at 150 °C and 10 MPa exhibits λ t value of 0.66 W/m K. Upon mixing of polystyrene microspheres, λ t is successfully increased. The maximum value of thermal conductivity for a composite sheet with 35 wt% of graphite and 50 wt% of spherical particles is 7.51 W/m K, at 180 °C and 10 MPa. The graphite‐containing polymer matrix forms a sequentially connected network‐like structure in the composite sheet. Excess polymer microspheres lead to the formation of void structures inside the composite sheet, reducing the thermal conductivity. Thermo‐camera observations proved that the composite sheets with higher λ t value showed comparably high heat radiations. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020, 58, 607–615