Interfacial Binding Energy Research Articles

Thermal properties and mechanical behavior of functionalized carbon nanotube-filled polypropylene composites using molecular dynamics simulation

Polypropylene (PP) is widely recognized as an environmentally friendly material for cable insulation due to its good insulation performance and environmental friendliness. One common method for enhancing the overall performance of PP is the addition of nanoparticles. To analyze the influence of different functionalized multi-walled carbon nanotubes (MWCNT) fillers on the properties of PP/MWCNT composite materials from a microscale perspective, molecular dynamics is used to construct pure PP models and models filled with untreated carbon nanotubes (UFCNT), amino-functionalized carbon nanotubes (AFCNT), carboxyl-functionalized carbon nanotubes (CFCNT), and hydroxyl-functionalized carbon nanotubes (HFCNT) (functionalized MWCNT with 4 or 8 functional groups grafted onto them). The simulation results indicate that the doping of nanotubes can effectively enhance the thermodynamic properties of PP. Among them, PP/CFCNT-8 exhibits the most significant improvement in melting temperature and mechanical properties, with an increase in melting temperature of 88.85 K and a 184.52 % increase in Young's modulus. The melting temperature of PP/HFCNT-8 is second only to PP/CFCNT-8, with an increase of 82.59 K. The results indicate that the thermodynamic properties of PP nanocomposites filled with functionalized MWCNT are improved with the grafting rate. The filling of functionalized MWCNT alters the microscale properties of PP composites, with a significant decrease in root mean square displacement (RMSD), and improvement in free volume fraction (FFV) as well as interfacial binding energy, which can better maintain the electrical properties of PP insulation materials. Applying functionalized carbon nanotubes to filled PP can significantly increase the electrical insulation properties of PP cable materials, which provides meaningful guidance for adopting polypropylene cable insulation materials.

The effect of binding energy on optimizing the interfacial thermal transport in metal-MoS2-dielectric nanostructures

The development of MoS2-based devices presents a significant challenge due to the poor interfacial thermal transport of metal-MoS2-dielectric structures, which results in severe thermal dissipation issues. This work aims to investigate the effects of various strategies, including modifying metal electrodes, adjusting the number of MoS2 layers, and incorporating van der Waals heterostructures, on the enhancement of interface thermal conductance (ITC) of metal-MoS2-dielectric structures. The time-domain thermoreflectance method was applied to characterize the ITC and experimental results demonstrate that the effect of regulating metal electrodes depends on the binding energy between the metal-MoS2 interfaces, which is a matter of controversy due to the large dispersion of published results. Furthermore, the increase in the number of MoS2 layers does not necessarily lead to the enhancement of the ITC of metal-MoS2-dielectric structures, as this is a comprehensive reflection of the number of layers' influence on both thermal conductance of MoS2 itself and the ITC between MoS2 and the surrounding materials. The results from the heterostructures of hBN-MoS2 and Gr-MoS2 were then systematically compared, and the results indicate the potential of Gr-MoS2 heterostructures in augmenting ITC. In addition, the nonequilibrium molecular dynamics simulation was effectively employed to gain deeper insights into the effect of binding energy on optimizing the ITC of metal-heterostructures-dielectric nanostructures. Finally, the effectiveness of these strategies in enhancing thermal properties was discussed through an analysis of interfacial binding energy. This finding provides a valuable direction for enhancing the thermal management of MoS2-based devices.

Anchoring movable Ag2CO3 quantum dots on g-C3N4 with rich oxygen vacancies for enhanced simulated-sunlight CO2 reduction in water medium

Z- scheme Ag2CO3 quantum dots (QDs) decorated g-C3N4 photocatalysts (g-C3N4/Ag2CO3, CA) with rich interface oxygen vacancies (Ov) were prepared by calcination and precipitation method. The highest yields of photocatalytic CO2 reduction reaction (CO2RR) over 15 mg of photocatalysts are 7.006 (CO, CA4) and 8.039 μmol·g−1 (CH4, CA3) for 5 h under simulated sunlight irradiation, respectively. The yields in CA composites are 1.90, 1.46 (CO) and 1.85, 1.60 (CH4) times higher than those of pristine g-C3N4 and Ag2CO3, respectively. When the amount of the photocatalysts increases to 30 mg, the yield of CA4 is 17.158 μmol·g−1 (CO). According to density functional theory (DFT) calculations, the key roles of Ov are the decrease of Gibbs-free energy for *COOH and interface binding energy. The Ov of Ag2CO3 QDs exhibit an electron capture effect, and the electrons can be extracted and transferred to surface active sites via synergistic effect of a rich Ov and Ag interface channel (Ag-Ov-Ag-N pathway). Furthermore, rich Ov Ag2CO3 QDs can move, rotate and disperse on g-C3N4 (002) surface through the relaxation and formation of interface Ag-N bonds during CO2RR process. The structure reconstruction of Ag2CO3 QDs on g-C3N4 not only improves the uniformity of Ag2CO3 QDs, but also exhibits a positive influence on photocatalytic efficiency. The DFT results also reveal optimized Lewis sites and possible kinetic CO2RR pathways for CO and CH4, respectively. The CO2RR pathways are CO2 ∼ *COOH ∼ *CO ∼ *+CO and CO2 ∼ *COOH ∼ *CO ∼ *CHO ∼ *CH2O ∼ *CH3O ∼ *CH4 ∼ *+CH4, respectively. The work provides a novel photocatalytic mode via a self-adjusting behavior of QDs to improve photocatalytic activity.

MoO3 facilitator enables ultrathin and stabilized Li metal anode for quasi-solid-state batteries

Lithium metal is considered as a highly desirable anode for high-energy and safe quasi-solid-state batteries. Nevertheless, the terrible wettability of molten lithium does not permit it to spread out on the lithiophobic current collectors, limiting their practical applications. Herein, we report an ultrathin lithium–molybdenum (Li–Mo) composite anode to settle this hurdle by reacting molten Li with α-MoO3 nanobelts. The experimental characterizations and density functional theory calculations reveal that the interfacial binding energy between molten Li and copper (Cu) foil can be decreased by adding α-MoO3, which improves the wettability toward Cu current collector and helps to realize uniform spreading of an ultrathin Li with a thickness of ∼35 μm. As a demonstration, the ultrathin Li–Mo is stabilized to provide a high average Coulombic efficiency of ∼95.2% over 300 cycles at a high current density of 1 mA cm−2, and a capacity retention of 100% is realized for a quasi-solid-state battery paired with LiFePO4 and poly(1,3-dioxolane) electrolyte. These findings open up a promising option for enhancing the wettability of molten lithium and provide a sustainable strategy for the large-scale production of ultrathin lithium for realizing next-generation high-energy and safe quasi-solid-state batteries.

Study on the properties of C-S-H/epoxy nanocomposite structure doped with silica nanoparticles

Nano-SiO2 can promote cement hydration, and it is important to study the effect of nano-doping technology on the microstructure of C-S-H/epoxy resin to improve the performance of epoxy resin cement materials. In this paper, the coupling agent (kh550) molecules were grafted on the surface of nano-SiO2, and the nano-SiO2-modified epoxy resin with different grafting rates was modeled and compounded with C-S-H. The structural properties and interfacial interaction mechanism were discussed utilizing molecular dynamics (MD) simulations. The results show that: nano-SiO2 doping into epoxy resin can increase its atomic surface area, reduce the porosity and thus enhance the stiffness of the composite, and the mechanical properties are best at a surface grafting rate of 15%; with the increase of nano-SiO2 doping and cross-linking degree, the amorphous characteristics of the composite structure are reduced and the crystalline structure of C-S-H in molecular motion is optimized. At the same time, the spacing between the C-S-H layer and epoxy resin layer in the composite structure is reduced, and the interfacial binding energy is increased; due to the improved adsorption performance, the diffusion rate of Ca ions between the C-S-H and epoxy resin layers is enhanced, this phenomenon facilitates the production of hydration products.

Co-modulated interface binding energy and electric field distribution of layer-structured PVDF-LDPE dielectric composites with BaTiO3: experiment and multiscale simulations

Co-modulated interface binding energy and electric field distribution of layer-structured PVDF-LDPE dielectric composites with BaTiO3: experiment and multiscale simulations

Ab initio investigation on the ordering mechanism of L12 phase in Al–Zr–Y(Sc) alloy

The L12-Al3Y(Sc) phase promotes the precipitation kinetics of Al3Zr. However, although Al3Y and Al3Sc are both with L12 structures, the mechanisms are not entirely the same due to different structures of the compound composites: Al3(Zr, Sc) has a core-shell structure, while Al3(Zr, Y) does not. Formation mechanisms of core-shell and non-core-shell structures were revealed in this work through analyzing surface energy, interface binding energy, and interface energy. The results showed that the interface energy and the lattice mismatch of Al/Al3Sc and Al/Al3Y are 0.011 J/m2,1.9% and 0.512 J/m2 and 5% respectively. During the growth of Al3(Zr, Sc) with Al3Sc as the heterogeneous core, the interface energy decreased linearly with increasing Zr contents at the interface and eventually a Zr rich shell formed. However, during the formation of Al3(Zr, Y), the interface energy fluctuated with changes in the composition and Zr(Y) content at the interface, eventually forming a composite phase shell of Al3Y(Zr). The diffusion migration energy for Zr atoms in pure Al was 1.102 eV, and it increased by at least 2% near the Al/Al3Sc interface, while it decreased by up to 46.3% near the Al/Al3Y interface. The impact of the L12-Al3Y(Sc) heterogeneous core on the diffusion ability of Zr atoms is crucial for its influence on the kinetics of Al3Zr precipitation.

First principles calculations of interfacial adhesion energy between Fe substrate and transition layer of films

Transition metal nitride films have high hardness and low wear rate, but the film substrate bonding strength between the film and the Fe substrate determines whether the film is useable. Adding transition layer materials is an effective way to improve the bonding strength of the membrane substrate. This article selects Ti, Zr, Hf, V, Cr, Ta, and TiN as transition layer materials, and uses first principles to calculate the interface bonding energies of ten interface models: Fe/TaN, Fe/Cr, Fe/V, Fe/Ti, Fe/Zr, Fe/Hf, Fe/Ta, Fe/TiN, Ti/TiN, and TiN/TaN. The model with higher bonding energy is selected to calculate the atomic population, electron gain and loss, and partial wave density of states of atoms, and further study the bonding situation at the interface. By comparing the bonding energy, the interfacial bonding energy between Fe and transition layer materials Ti, V, Cr, Ta, and TiN is higher than that of Fe and TaN films. And the interfacial binding energy of Fe/Ti, Ti/TiN and TiN/TaN are 0.3041eV/Å2, 0.4217eV/Å2 and 0.3687eV/Å2, respectively, which are higher than that of Fe and TaN film. Therefore, when preparing TaN thin films on Fe substrates, adding a double transition layer material Ti/TiN between the Fe substrate and TaN thin films, forming an interface model with a four layer structure of Fe/Ti/TiN/TaN, can optimize the bonding force between the substrate and the film to the greatest extent.

Characterization of Type I/II g-C3N4/MoS2 van der Waals Heterostructures: A New Theoretical Insight.

The charge transfer mechanism of the g-C3N4/MoS2 heterojunction is still disputed. Some regard it as a type I pathway, some regard it as a type II pathway, and still some regard it as a Z-scheme pathway. Especially, the results obtained by density functional theory (DFT) calculations are not totally in agreement. Here, we constructed four g-C3N4/MoS2 heterojunctions on the basis of the aperture alignment modes of g-C3N4 and MoS2. Their morphology and photocatalytic activity were investigated via first-principles and excited state dynamics simulations. By systemically comparing the interfacial binding energy and electronic structure (e.g., band structure, electrostatic potential, and band edge positions) of g-C3N4/MoS2 heterojunctions, we found that both type I and type II band alignment structures could be obtained. Moreover, the calculated lifetimes of interlayer photogenerated electrons and holes show that type II g-C3N4/MoS2 tends to favor a general type II pathway rather than a Z-scheme pathway. This study could provide a deep understanding of the photocatalytic mechanism of g-C3N4/MoS2 van der Waals heterostructures, which will be of great use for applications in photocatalysis.

Theoretical design and experimental study a novel direct Z-scheme V2O5/C3N5 heterojunction for efficient photocatalytic hydrogen production

The key to construct an efficient direct Z-scheme heterojunction lies in the selection of two semiconductors with matching Fermi energy levels, visible light response capability and the elaborately designed interface. Herein, a research method that theoretical calculation first and then experimental study was employed to develop an efficient direct Z-scheme V2O5/C3N5 photocatalyst for hydrogen production. First, the theoretical calculations on the V2O5 (110)/C3N5 (001) heterojunction suggested the large interface binding energy between these two components, their visible-light absorption properties and matching Fermi energy levels, and the charge difference density of V2O5/C3N5 allowing the migration path of photogenerated carriers in composite structure, which satisfies the requirements for constructing a direct Z-scheme. Then, the V2O5/C3N5 heterojunction was experimentally constructed by calcining the mixture of 3-amino-1,2,4-triazole and ammonium metavanadate, which Z-scheme charge transfer path was further verified by free radical trapping and in situ irradiated XPS analyses. We also found that N–O bonding was formed between C3N5 and V2O5, which could provide a favorable interface for facilitating the charge transfer within the heterojunction. The optimal V2O5/C3N5-3.7 heterojunction exhibited a H2 yield of 329.9 μmol/h under the visible light irradiation, 19.8 times that of single C3N5, and showed an apparent quantum efficiency of 7.21% at 420 nm. The high charge separation of the V2O5/C3N5 heterojunction is revealed to be mainly responsible for the enhancement in its photocatalytic activity. This work sheds light on the research method that consists of theoretical design first and then experimental study for constructing high-efficiency direct Z-scheme heterojunctions.

Calcium silicate/polyvinyl/chitosan/alginate-based bioceramic slurry for 3D printing of scaffolds: Interfacial interactions – Mechanical properties relationship

At present, there are few studies investigating the influence of mechanical properties of binders on bioceramic slurry at the micro- and macroscopic levels. In this work, we used molecular dynamics (MD) simulations and experiments to investigate the influence of mechanical properties of polyvinyl alcohol (PVA), chitosan (CS), and sodium alginate (SA) polymers on calcium silicate (CSi, CaSiO3)/binder bioceramic slurry and to choose the most suitable binders to prepare CSi/binder slurry. It was found that PVA demonstrated excellent stiffness, ductility, toughness, solubility, and low shear thinning. The formation of large number of hydrogen bonds (HBs) at the CSi/PVA interface results in strong interfacial bonding and higher compressive strength of CSi/PVA slurry while other binders suffer low solubility, higher shear thinning, poor stiffness, and ductility problems. From the calculated mechanical parameters, interfacial binding energy, and compressive tests, it was found that the slurry prepared by CSi and 10 PVA (mixing ratio: 1:0.9) demonstrate the best mechanical properties, a compressive strength of 7.3 MPa, thus, meeting the requirements of compressive properties of cancellous bone defects. The simulation results were supported by experiments. This study provides a theoretical and experimental guide for binder selection in bioceramic slurry and the design of future binder composites.

Effect of surface grain structure on reaction of residual glass phase with hydrofluoric acid in glass-ceramics

The rapid reactivity of hydrofluoric acid (HF) and irregular Si-O network has been successfully applied in the chemical processing of glass/glass-ceramics surface. It is found that the low glass and diopside (D-G) interface binding energy will promote the reaction of HF and the residual glass phase at the interface, resulting in the formation of defects and the fall of grain. Raman spectroscopy has found that residual stress will be generated on the surface of the sample during corrosion, which will improve the performance of glass-ceramics, and the Vickers hardness increases from 761.5HV to 834.8HV. The corrosion process can be divided into three stages, including reaction of glass phase with hydrofluoric acid, formation of sediment on the surface of glass-ceramics and a corrosive layer. The whole process is closely related to insoluble crystal phase, which provides a theoretical basis for the study of hydrofluoric acid processing glass/glass-ceramics.

Effect of asphaltene structure characteristics on asphaltene accumulation at oil-water interface: An MD simulation study

Asphaltenes possess the ability to accumulate at the interface of oil and water, leading to the formation of stable emulsions. These emulsions pose significant challenges in oil transportation and processing. In order to investigate the impact of asphaltene structure on the stability of the oil-water interface, various models were created using molecular dynamics simulations. These models involved modifications in the number of aromatic rings and types of oxygen-containing functional groups present in the asphaltenes. To support the findings, several analyses, such as radial distribution function, binding energies, and interface formation energy, were conducted. The simulation results indicate that an increase in the number of aromatic rings in the asphaltenes significantly enhances the binding energy at the emulsion interface, from − 215 kcal/mol to − 383 kcal/mol. This increased binding energy greatly improves the stability of the interface. Furthermore, altering the types of oxygen-containing functional groups and binding sites results in a change in the interface binding energy from − 381 kcal/mol to − 526 kcal/mol. The oxygen-containing functional groups of the asphaltene side chain vertically enter the water, forming a crosslinked structure. The polarity of these functional groups can influence the strength of the crosslinked structure, thereby impacting the stability of the interface. This paper establishes the relationship between changes in asphaltene structure and the aggregation state and energy of the interface, offering theoretical insights for future research on new demulsifiers.

Influence of water penetration on glass fiber-epoxy resin interface under electric field: A DFT and molecular dynamics study

Water penetration is a primary cause of composite insulator core rod deterioration. The performance of the glass fiber-epoxy resin (GFEP) interface plays a crucial role in determining the overall performance of the core rod, and the interface is also affected by an electric field. In this study, molecular dynamics (MD) simulation, reactive force field (ReaxFF), and density functional theory (DFT) simulation techniques were employed to analyze the changes in various parameters, including interface binding energy, free volume, Mayer Bond Order (MBO), hydrogen bond number and distribution, chemical groups, radial distribution function (RDF), and others. The influence of the electric field on these parameters was investigated based on the operational conditions. The results showed that the electric field yielded little effect on the dry GFEP model. However, in the presence of water penetration, the system exhibited a “swelling-collapse” phenomenon under the electric field, and the free volume will increase with the increase of the electric field strength. Analysis of hydrogen bond number, water molecule dipole moment, and water molecule RDF indicated that the electric field could induce the polarization of water molecules, causing their migration towards the epoxy resin ester groups and glass fiber, and form hydrogen bond interaction with them respectively. Consequently, the effective hydrogen bond between the glass fiber and epoxy resin decreased. Additionally, DFT simulation showed that the electric field altered the energy of frontier molecular orbitals, promoting the decrease in the MBO of the epoxy resin ester group C-O bond and water molecule O–H bond, thereby increasing the chemical reactivity between the epoxy resin and water molecules, and facilitated the hydrolysis of the glass fiber and epoxy resin. The synergistic effects of these processes ultimately led to interface failure. This research sheds light on the effects of water penetration on the interface between glass fiber and epoxy resin under the influence of an electric field, which is important for improving the overall performance of composite insulators.

Improving the mechanical performances of polymer bonded explosives using monomer tuned polythioureas

To improve the mechanical properties of 2,4,6-trinitrobenzene-1,3,5-triamine (TATB)-based polymer bonded explosives (PBXs), four kinds of polythiourea binders, namely the polyetherthiourea (P1), aliphatic polythiourea (P2), aromatic polythiourea (P3) and silane polythiourea (P4), were prepared and used in the PBXs. These four polythioureas were synthesized via the copolymerization of carbon disulfide (CS2) and diamines with various structures under mild conditions. They were then characterized using nuclear magnetic resonance (NMR) and Fourier-transform infrared spectroscopy (FTIR). The interfacial binding energy between polythioureas and TATB was calculated via molecular dynamics simulations. The tensile and compression mechanical properties of various PBXs (PBX-Pn, n ​= ​1–4) were studied through Brazilian and compression tests and were then compared with those of the PBX with a conventional fluoro polymer binder (PBX-FP). The results show that the PBX-P1 possessed the strongest interfacial interaction energy and the best mechanical properties among all the prepared PBXs. Its Brazilian strength and strain was 11.0 ​MPa and 0.56%, which was 89% and 256% higher than those of the PBX-FP with the same binder proportion, respectively. Furthermore, PBX-P1 showed excellent compression mechanical properties, with a compression strength of 40.7 ​MPa and a compression strain of 3.53%. Moreover, its Brazilian and compression fracture energy was 600% and 101% higher than those of PBX-FP, respectively, which was beneficial for improving the PBX stability. The results of this study provide a new idea for designing TATB-based PBX with improved mechanical properties using polyetherthiourea binders.

Improving the Mechanical Properties of CCFRPLA by Enhancing the Interface Binding Energy and Strengthening the Anti-Separation Ability of a PLA Matrix.

Additive manufacturing (AM) can produce almost any product shape through layered stacking. The usability of continuous fiber-reinforced polymers (CFRP) fabricated by AM, however, is restricted owing to the limitations of no reinforcing fibers in the lay-up direction and weak interface bonding between the fibers and matrix. This study presents molecular dynamics in conjunction with experiments to explore how ultrasonic vibration enhances the performance of continuous carbon fiber-reinforced polylactic acid (CCFRPLA). Ultrasonic vibration improves the mobility of PLA matrix molecular chains by causing alternative fractures of chains, promoting crosslinking infiltration among polymer chains, and facilitating interactions between carbon fibers and the matrix. The increase in entanglement density and conformational changes enhanced the density of the PLA matrix and strengthened its anti-separation ability. In addition, ultrasonic vibration shortens the distance between the molecules of the fiber and matrix, improving the van der Waals force and thus promoting the interface binding energy between them, which ultimately achieves an overall improvement in the performance of CCFRPLA. The bending strength and interlaminar shear strength of the specimen treated with 20 W ultrasonic vibration reached 111.5 MPa and 10.16 MPa, respectively, 33.11% and 21.5% higher than those of the untreated specimen, consistent with the molecular dynamics simulations, and confirmed the effectiveness of ultrasonic vibration in improving the flexural and interlaminar properties of the CCFRPLA.

Multiscale Enhancement Mechanisms of EVA on EPS-Cement Composites

Ethylene-vinyl acetate (EVA) lotion can significantly improve the interface problems caused by the physical and chemical differences between expanded polystyrene (EPS) beads and cement, which is one of the reasons why EPS cement composites are widely used in the construction field. However, the research on its problems is often limited to phenomenological engineering methods, ignoring the potential interaction mechanism in atomic structure. Therefore, in this study, the strengthening mechanism of EVA on EPS particle–cement slurry interface was systematically studied from the aspects of macromechanical properties, microstructure characteristics, chemical composition, and molecular structure. In terms of physical test, it was found that the compressive strength and flexural strength of EPS-cement-based materials containing EVA are increased by 19% and 31%, respectively, at 28 days when the content of EPS particles is the same. It was observed through an electron microscope snapshot that EVA makes a uniform and dense interface structure between EPS particles and cement. For chemical tests, EPS particle surface hardening cement was ground into powder and tested by X-ray diffraction and Fourier transform infrared spectrometer. It was comprehensively analyzed that EVA reduced the hydration product Ca(OH)2 and increased calcium silicate hydrate (C-S-H) at the interface. In terms of numerical simulation, through molecular simulation modeling and calculation, it was found that the introduction of EVA can produce more stable hydrogen and ion bonds at the EPS–C-S-H interface, which plays a vital role in reducing the interface effect and increasing the interface binding energy.

Flexible solid-solid phase change materials with high stability for thermal management

Phase change materials are considered as a promising technology to solve problems such battery thermal management. However, during the process of charging and discharge, the migration of microscopic components in PCM and the brittle fracture caused by high rigidity of PCM will hinder the application of PCM in the thermal management field. In this paper, a polyurethane (PU) phase change material was prepared, and by weighing the relationship between thermal storage capacity and mechanical properties of PCM, PU4000 was considered to be the best choice with latent heat and strain of 98.8 J/g and 10%. In addition, the interfacial interaction of carbon nanotubes (CNT) and hydroxylated carbon nanotubes (CNT-OH) with the PU was analyzed at the microscopic scale, and the results showed that CNT-OH has stronger interfacial binding energy with the phase change matrix. Therefore, CNT-OH was used to improve the heat transfer performance of PU4000. The thermal conductivity of the composites reached 1.3 W/(m·K) at 5% CNT-OH content. At 2C discharge rate, the phase change material keeps the maximum temperature and maximum temperature difference of the battery module within 50 and 2 °C.

Effects of Structure Defects on Thermal Transport at the Graphene–Water Interface

AbstractThe graphene microchannel heat sinks have attracted extensive attention due to its high cooling efficiency in microelectric devices. The interfacial thermal resistance (ITR) between graphene as the bottom layer of microchannel and water is one of the key factors of its good working performance. In this paper, the impacts of structure defects in graphene surfaces on ITR of the graphene–water interface are investigated using molecular dynamic simulations. The results indicate that graphene layer with different types of structure defects shows different variation trends of ITR as the defect concentration or temperature increases. A peak ITR reduction of nearly 30% is generated with the Stone‐Wales defect of 2%. Finally, the density of phonon states and interfacial binding energy analysis are performed to verify the correctness of the simulation results. The present work expands the understanding of structure defects effect on thermal transport in graphene microchannel.

The Role of the Interface of PLA with Thermoplastic Starch in the Nonisothermal Crystallization Behavior of PLA in PLA/Thermoplastic Starch/SiO2 Composites

Corn starch was plasticized by glycerol suspension in a twin-screw extruder, in which the glycerol suspension was the pre-dispersion mixture of glycerol with nano-SiO2. Polylactide (PLA)/thermoplastic starch/SiO2 composites were obtained through melt-blending of PLA with thermoplastic starch/SiO2 in a twin-screw extruder. The nonisothermal crystallization behavior of PLA in the composites was investigated by differential scanning calorimetry. An interface of PLA with thermoplastic starch was proven to exist in the composites, and its interfacial bonding characteristics were analyzed. The interfacial binding energy stemming from PLA with thermoplastic starch exerts a significant influence on the segmental mobility of PLA at the interface. The segmental mobility of PLA is gradually improved by increasing interfacial binding energy, and consequently, the relative crystallinity on the interface exhibits progressive promotion. The Jeziorny model could well describe the primary crystallization of PLA in the composites. The extracted Avrami exponents based on the Jeziorny model indicate that the primary crystallization of PLA follows heterogeneous nucleation and three-dimensional growth. This study has revealed the intrinsic effect of the interfacial segmental mobility on the nonisothermal crystallization behavior of PLA in composites, which is of technological significance for its blow molding.