Solid Filler Research Articles

Vertically aligned liquid metal thermal pad with excellent electromagnetic shielding and ultra-high compressibility

With the increasing integration level of modern electronics, flexible highly thermally conductive and electromagnetic interference shielding (EMI) materials were urgently demanded in electronic devices. Traditionally carbon or solid metal fillers are widely used as a reinforcement to fabricate a flexible thermally conductive and EMI shielding materials. However Due to the trade-off between mechanical and thermal properties, it is difficult to further improve the performance of solid filler/polymer composites. Here in this work based on the intrinsic excellent electrical and thermal conductivity of liquid metal (LM), we embedded the LM network structure vertically in the silicone gel and fabricated a vertically aligned LM(VALM) composites. Compared to the randomly dispersed LM composites, VALM composite exhibits high through plane thermal conductivity (κ⊥: 6.08 W/m·K) and excellent EMI shielding efficiency (SE) (minimum and maximum EMI SE for VALM2 were 33.2 dB and 39.5 dB). In addition, due to the fluidic nature of LM, composite materials exhibit excellent softness and flexibility (compression modulus of 0.56 MPa). Practical heat dissipation test results and EMIS efficiencies demonstrate usefulness of VALM composite in next-generation electronics.

ZnO Quantum Dots as PEO-Based Solid Electrolytes Fillers for Lithium Metal Batteries.

PEO-based solid polymer electrolyte (PEO SPE) is regarded as one of the most promising solid electrolytes due to its exceptional flexibility, cost-effectiveness, and ease of integration. However, its commercialization is hindered by inadequate ionic conductivity and unstable interface. By incorporating proper ZnO quantum-dots (QDs) fillers with enhanced surface activity, the ion transport inner the PEO-based electrolyte can be improved along with enhanced REDOX kinetics at the Li/PEO interface. The ionic conductivity reaches 5.97×10-4 S cm-1 at 60 °C. Moreover, ZnO QDs exhibit a quantum size effect and possess lithiophilic characteristics that promote uniform nucleation and redeposition of Li+ while forming a stable Li-Zn alloy. This inhibits lithium dendrite formation and enhances the stability of Li anode. Li//Li cell with 3 % ZnO QDs works steadily for more than 2100 h at 60 °C with 0.1 mA cm-2. The assembled Li//LiFePO4 cell provides a reversible capacity of 134.91 mAh g-1 after200 cycles at 0.1 C.

Experimental investigation of a low-temperature packed-bed thermal storage system with graphite-based composite phase change material

The thermocline latent heat packed bed system has the potential to be used for >200 °C high-temperature, 100–200 °C medium-temperature, and <100 °C low-temperature thermal energy storage applications. However, the inherent shortcoming of phase change material (PCM) is its low thermal conductivity, which inevitably restricts the heat transfer between the fillers and the heat transfer fluid. This study aims to investigate the thermal performance of the packed bed thermal energy storage (PBTES) system at mass flow rates of Re = 23-68 by filling the tank with high thermal conductivity composite PCM. An encapsulated expanded graphite/stearic acid composite PCM with a cylindrical aluminum shell was designed to prevent leakage and used as filler. The thermal conductivity of the composite is 305.7 % higher than that of pure PCM, demonstrating a higher thermal storage rate for a single capsule. Results show that this composite used as filler leads to a faster heat transfer rate between heat transfer fluid and solid fillers, decreasing the charging time by approximately 23.8 %, and keeping a more stable and distinct phase change platform at 55–60 °C. Moreover, an appropriate increase in the mass flow rate can facilitate heat transfer and improve the thermal performance of PBTES. Nevertheless, the thermal storage capacity utilization is reduced accordingly. Compared to the system with pure PCM fillers, the system with composite fillers exhibits a higher charging efficiency of 86.27 %, a higher stored thermal energy of 0.448 kWh, and a higher utilization rate at the threshold temperature. Overall, the thermal conductivity of filler is one of the primary parameters to determine the thermal performance of the thermocline latent heat packed bed system.

Multi-pass weld influence on metallurgical, tensile, impact toughness and fatigue crack growth behavior of gas tungsten arc welded Ti-6Al-4V joints

A comparative study on the influence of changing the number of weld passes on the metallurgical and mechanical properties of Ti-6Al-4 V alloy was carried out. Two welded joints involving 3-pass and 4-pass welding procedure were fabricated for 7 mm thick Ti-6Al-4 V plates using gas tungsten arc welding (GTAW) process. A compatible solid filler of Ti-6Al-4 V was used to weld these plates. A significant variation in the microstructure and the microhardness of the upper part of the fusion zones of these welds was observed. Equiaxed microstructure possessed by the base metal resulted into relatively better transverse tensile strength, ductility, and impact toughness than the 3-pass and the 4-pass weld. Widmanstätten and martensite-α′ microstructure associated with the fusion zone of the 3-pass weld resulted into a larger fraction of high angle grain boundaries (HAGBs) which accounted for higher resistance to fatigue crack propagation in this weld. Fusion zone of the 4-pass weld possessed lamellar and basketweave microstructure which had a lower fraction of HAGBs and, hence exhibited relatively lower resistance to fatigue crack propagation as compared to the 3-pass weld. However, equiaxed microstructure of the base metal could not offer much resistance to fatigue crack propagation, which resulted into relatively poor fatigue performance of the base metal. These fatigue studies indicate that both the weld joints exhibited better fatigue crack resistance than the base metal. This study established that 7 mm thick Ti-6Al-4 V joint welded using 3-pass welding procedure resulted into superior mechanical properties than those obtained by using 4-pass welding procedure.

Design of Quasi‐Metal–Organic Frameworks for Solid Polymer Electrolytes Enabling an Ultra‐Stable Interface with Li Metal Anode

AbstractSolid polymer electrolytes (SPEs) are crucial in the development of lithium metal batteries. Recently, metal–organic frameworks (MOFs) with open metal sites (OMSs) have shown promise as solid fillers to improve the performance of SPEs. However, the number of OMS‐containing MOFs is quite limited, comprising less than 5% of the total MOFs. When considering yield, cost, and processability, the commonly used OMS‐containing MOFs are no more than 10 types, causing great limitations. Herein, we reported a simple and universal methodology that converted OMS‐free MOFs to OMS‐rich quasi‐MOFs for developing high‐performance SPEs, and explored the underlying mechanism. The “OMS‐polymer” and “OMS‐ion” interactions were investigated in detail to elucidate the role of quasi‐MOFs on battery performance. It was found that quasi‐MOFs, functioning as ion sieves, can effectively regulate ion migration, thus promoting uniform Li deposition and enabling an ultra‐stable interface. As a result, the Li symmetric cell stably ran over 3000 h at 0.3 mA cm−2, while the full cell retained 85 % of its initial capacity after 1500 cycles at 1.0 C. Finally, universal testing was performed using other MOFs, confirming the generalizability and effectiveness of our design concept.

In Situ Alloying Enabled by Active Liquid Metal Filler for Self‐Healing Composite Polymer Electrolytes

AbstractSolid inorganics, known for kinetically inhibiting polymer crystallization and enhancing ionic conductivity, have attracted significant attention in solid polymer electrolytes. However, current composite polymer electrolytes (CPEs) are still facing challenges in Li metal batteries, falling short of inhibiting severe dendritic growth and resulting in very limited cycling life. This study introduces Ga62.5In21.5Sn16 (Galinstan) liquid metal (LM) as an active liquid alternative to conventional passive solid fillers, aiming at realizing self‐healing protection against dendrite problems. Compared to solid inorganics, for example silica, LM droplets could more significantly reduce polymer crystallinity and enhance Li‐ion conductivity due to their liquid nature, especially at temperatures below the polymer melting point. More importantly, LMs are unraveled as dynamic chemical traps, which are capable of blocking and consuming lithium dendrites upon contact via in situ alloying during battery operation and further inhibiting dendritic growth due to the lower deposition energy barrier of the formed Li‐LM alloy. As a proof of concept, by strategically designing an asymmetric CPE with the active LM filling, a solid‐state Li/LiFePO4 battery achieves promising full‐cell functionality with notable rate performance and stable cycle life. This active filler‐mediated self‐healing approach could bring new insights into the battery design in versatile solid‐state systems.

In Situ Alloying Enabled by Active Liquid Metal Filler for Self-Healing Composite Polymer Electrolytes.

Solid inorganics, known for kinetically inhibiting polymer crystallization and enhancing ionic conductivity, have attracted significant attention in solid polymer electrolytes. However, current composite polymer electrolytes (CPEs) are still facing challenges in Li metal batteries, falling short of inhibiting severe dendritic growth and resulting in very limited cycling life. This study introduces Ga62.5In21.5Sn16 (Galinstan) liquid metal (LM) as an active liquid alternative to conventional passive solid fillers, aiming at realizing self-healing protection against dendrite problems. Compared to solid inorganics, for example silica, LM droplets could more significantly reduce polymer crystallinity and enhance Li-ion conductivity due to their liquid nature, especially at temperatures below the polymer melting point. More importantly, LMs are unraveled as dynamic chemical traps, which are capable of blocking and consuming lithium dendrites upon contact via in situ alloying during battery operation and further inhibiting dendritic growth due to the lower deposition energy barrier of the formed Li-LM alloy. As a proof of concept, by strategically designing an asymmetric CPE with the active LM filling, a solid-state Li/LiFePO4 battery achieves promising full-cell functionality with notable rate performance and stable cycle life. This active filler-mediated self-healing approach could bring new insights into the battery design in versatile solid-state systems.

IMMISCIBLE POLYMER–FILLER SYSTEMS FOR TUNABLE MECHANICAL PROPERTIES

ABSTRACT A model system consisting of a 50/50 immiscible mixture of polyethylene glycol (PEG) and polytetrahydrofuran (PTHF), with covalently bound nano silica–reinforcing particles, was used to investigate how the distribution of particles affects viscoelastic properties. The rubbery polymers were generated by chain extending from their respective oligomers through hydroxyl end groups with 1,6-diisocyanato hexane. The viscosity of the resulting PEG and PTHF polymers was 32 and 1000 Pa-s, respectively. Setting the overall SiO2 concentration to 10 phr, we explored three different silica distributions: (1) all-in-PEG, 20 phr in PEG and neat PTHF; (2) uniform, 10 phr in both PEG and PTHF; and (3) all-in-PTHF, neat PEG and 20 phr in PTHF. When compared with the uniform system, the storage and loss shear moduli and the viscosity of the all-in-PTHF system showed a 20-fold increase of the stiffness at low strain, yet nearly the same viscosity at high strain. Similarly, the storage and loss moduli of all-in-PEG mixtures were roughly 1/10 that of the uniform system. The surprisingly high modulus and high viscosity of the all-in-PTHF system can be understood as the entire PTHF regions themselves becoming solid filler.

Influence characteristic and improvement mechanism of thermal storage performance of Packed-bed thermocline tank based on high-temperature molten salt

Chloride salts and carbonates thermal energy storage (TES) have great application potential in high-temperature concentrated solar power (CSP) plants. However, their thermal storage characteristics, performance improvement mechanism and economic feasibility of application in high-temperature conditions are not clear. In this study, a transient, two-dimensional and axisymmetric model is developed for packed-bed thermocline tanks. The effects of six commonly solid fillers on thermal storage performance of NaCl-KCl-MgCl2 salt and Na2CO3-K2CO3-Li2CO3 salt at an operation temperature of 450–800 °C are simulated. The suggestions for optimizing fillers are provided combined with thermal and economic performance. Results show that high volume heat capacity and low thermal conductivity of fillers play important roles in deferring migration and weakening diffusion of thermocline, thus promoting thermal storage capacity and efficiency of tanks. Concrete and cast iron are suitable fillers for chloride salts and carbonates TES. The concrete tank is suitable for systems with strict cost control and low TES requirements. The iron tank is suitable for systems with high TES and low cost control requirements, which significantly increases effective thermal storage capacity of chloride salts by 222.1 % and considerably reduces TES cost of carbonates by 41.1 %. The results can be beneficial for high-temperature TES system of CSP plants.

Mechanical Properties and Thermal Decomposition Mechanism of Glycidyl Azide Polyol Energetic Thermoplastic Elastomer Binder with RDX Composite.

To improve the reinforcement effect between a binder and high solid filler in a propellant formula, grafting the bonding group into the binder to form a neutral polymeric is a practically novel approach to improving the interface properties of the propellant. In this work, a glycidyl azide polyol energetic thermoplastic elastomer binder with a -CN bonding group (GAP-ETPE) was synthesized, and the mechanical and thermal decomposition mechanism of GAP-ETPE with Hexogeon (RDX) model propellants were studied. The stress-strain results indicated that the tensile strength and strain of GAP-ETPE/RDX model propellants were 6.43 MPa and 32.1%, respectively. DMA data showed that the storage modulus (E') of the GAP-ETPE/RDX model propellants could increase the glass transition temperature (Tg) values, those were shifted to higher temperature with the increase in filler RDX percentages. TG/DTG showed the four decomposition stages of the decomposition process of the GAP-ETPE/RDX model propellants, and the thermal decomposition equation was constructed. These efforts provide a novel method to improve GAP-ETPE/RDX propellants mechanical property, and the thermal decomposition behavior of GAP-ETPE/RDX propellants also provided technical support for the study of propellant combustion characteristics.

Experimental investigation on the tribo-mechanical behavior of PMMA reinforced by solid lubricant filler for dental implant applications

This study investigates the enhancement of mechanical and tribological behavior in polymethyl methacrylate (PMMA) composites reinforced with graphene oxide (GO) as a solid lubricant filler for advanced biomedical applications, particularly dental implants. PMMA/GO composites were prepared with varying weight percentages of GO (0, 0.2, 0.5, 0.7, and 1 wt. %) to assess their impact on material performance. A noteworthy improvement in both tensile strength and Young’s modulus was detected, reaching up to 141% and 10.6%, respectively, at optimized GO loadings of 1%. Microstructural analysis utilizing scanning electron microscopy for the worn surface revealed enhanced dispersion and interfacial adhesion between GO and the PMMA matrix, reinforcing mechanical coherence. Tribological properties also demonstrated enhancement, with PMMA composites containing 1 wt. % GO exhibiting optimal mechanical and tribological characteristics compared to lower weight fractions. Moreover, microscopic examination revealed a shift in the wear mechanism of the PMMA-GO composite, which was attributed to the lower friction coefficient obtained by GO integration.

Establishment and evaluation of dynamic viscoelasticity constitutive model for asphalt mixtures based on PCA model: Utilizing coal-based synthetic natural gas slag and phosphogypsum whisker as substitute fillers

To promote the secondary utilization of solid waste in asphalt pavement and reduce resource waste and environmental damage, the fine solid waste powder from the secondary treatment of solid waste was used as a substitute filler to prepare asphalt mixtures. To more precisely characterize the effects of filler type and substitution ratio on the dynamic viscoelastic mechanical characteristics of asphalt mixtures, the dynamic modulus test was conducted on asphalt mixtures, while the dynamic modulus master curve of asphalt mixtures was established based on the time-temperature equivalent principle and the Sigmoidal function. The improved generalized Sigmoidal (IGS) model, five-parameter fractional Zener (FFZ) model, six-parameter fractional Zener (SFZ) model and ten-parameter fractional Zener (TFZ) model were used to construct the shrinkage frequency curves of different asphalt mixtures under different constitutive relationships, whereas the applicability of the constitutive models was further evaluated by the principal component analysis (PCA) model. The research results showed that the dynamic modulus and phase angle of the mixture exhibited a similar change rule with the variation of temperature and frequency, and the use of solid waste-based fillers could effectively reduce the effect of frequency variation on the viscoelasticity of the mixture. The dynamic modulus master curve constructed by Sigmoidal function could accurately describe the functional relationship between the dynamic modulus with loading frequency and temperature, and the variation trend of dynamic modulus in a wider frequency range was flattened with the increase in frequency, and this change rule was not affected by the substitution ratio of the filler, while the use of solid waste-based filler could reduce the dependence of the mixture on the temperature. Compared to several fractional constitutive models, the IGS model exhibited a higher fitting accuracy for the dynamic viscoelasticity of several mixtures, and with the use of solid waste-based fillers, the deviation of fitting curves gradually decreased. A comparative study showed that the fractional constitutive model was difficult to accurately describe the dynamic viscoelasticity of the mixture, and the IGS model was preferred to be recommended as a calculation model to investigate the constitutive relationship on the dynamic viscoelasticity of the mixture.

Liquid Metal-Based Self-Healing Conductors for Flexible and Stretchable Electronics.

Flexible and stretchable electronics rely on compliant conductors as essential building materials. However, these materials are susceptible to wear and tear, leading to degradation over time. In response to this concern, self-healing conductors have been developed to prolong the lifespan of functional devices. These conductors can autonomously restore their properties following damage. Conventional self-healing conductors typically comprise solid conductive fillers and healing agents dispersed within polymer matrices. However, the solid additives increase the stiffness and reduce the stretchability of the resulting composites. There is growing interest in utilizing gallium-based liquid metal alloys due to their exceptional electrical conductivity and liquid-phase deformability. These liquid metals are considered attractive candidates for developing compliant conductors capable of automatic recovery. This perspective delves into the rapidly advancing field of liquid metal-based self-healing conductors, exploring their design, fabrication, and critical applications. Furthermore, this article also addresses the current challenges and future directions in this active area of research.

Porous liquids assisted in-situ generated Co-LDH@MOF heterostructure with abundant defects for flame retardant and mechanical enhancement in polyurea composites

Preventing aggregation and inducing homogeneous dispersion of flame retardant nanofillers is critical to enhance the fire safety and mechanical properties of nanocomposites. Although chemical modifications are commonly used to improve the filler’s compatibility with the polymer chain, such methods are often cumbersome and limited. Herein, porous liquids (PLs) with flame retardant function were constructed in which porous defect-Co-LDH@ZIF-67 (d-LDH@ZIF) heterostructure particles were converted into liquid materials by electrostatic interaction with a large-volume solvent. This is also the first report of PLs in the field of flame retardant. Specifically, the d-LDH@ZIF heterostructure was designed by defect engineering and in situ growth strategy to compensate for the low catalytic activity and specific surface area of Co-LDH, and to serve as a rigid porous framework for PLs. Numerous cobalt/oxygen vacancies and lattice defects in the d-LDH@ZIF heterostructure have also been proven to confer higher flame retardancy relative to Co-LDH. d-LDH@ZIF porous liquids (PLs-d-L@Z) presents favorable liquid characteristics and achieves a monodisperse state in the polyurea matrix. The limiting oxygen index of polyurea composites blended with 20 wt% PLs-d-L@Z (3 wt% d-LDH@ZIF content) can be increased to 24.2 % and pass the V-0 rating in the UL-94 test. Moreover, the peak of heat release rate, total heat release, and total smoke production are reduced by around 40.4, 27.0, and 39.9 %, respectively, compared to neat polyurea. Emphatically, the PLs-modified polyurea composites exhibit significantly improved mechanical and impact resistance properties, as well as favorable chemical resistance. This strategy of liquefying solid flame retardant fillers will open an avenue to the design of functional nanomaterials for fire safety and other potential applications.

Parametric study for a structured thermal energy storage system for concentrated solar power plants

The objective of this paper is to study and optimise thermal energy storage systems of structured thermocline type. The system consists of a solid filler material made from waste ceramic products and a set of channels through which the heat transfer fluid flows. A well-verified and validated unsteady and one-dimensional computational model was developed for this study. The investigation is carried out considering three main output values: outlet temperature, thermocline thickness and discharged exergy. The behaviour of several parameters, such as the flow velocity and cut-off temperature difference, the height and the diameter of the tank, together with the void fraction and the diameter of the channels, were studied. The results suggest that increasing the cut-off temperature, tank diameter and height, and/or void fraction reduces the thermocline thickness. Similarly, decreasing the flow velocity and/or channel diameter leads to a reduction in thermocline thickness. In order to increase the discharged exergy, it is necessary to reduce the cut-off temperature, flow velocity, or channel diameter while increasing the void fraction, as well as the diameter and height of the unit. This work outlines design guidelines aimed at optimising operational and geometrical parameters to achieve improved efficiency for structured thermocline systems.

Volumizing Threads (Jamber) in the Midface and Managing Side Effects: Clinical Cases.

The clinical application of polydioxanone (PDO) threads, traditionally utilized for tissue lifting, is now being explored for its volumizing effects in midface rejuvenation. The novel approach involves employing PDO volumizing threads to achieve physical augmentation akin to a "solid filler." The study introduces a more convenient insertion method for these threads, prioritizing ease and efficacy. Clinical cases demonstrate the efficacy of volumizing threads in addressing midface concerns, such as nasolabial folds and midcheek grooves. Additionally, the integration of volumizing threads to provide support in sagging areas is examined for achieving natural-looking enhancements. While highlighting positive outcomes, potential side effects like thread protrusion are addressed, along with strategies for their mitigation. Volumizing threads are presented as a suitable procedure for patients wary of traditional fillers or seeking subtle enhancements, with the recommendation of combining them with cog threads for those desiring more pronounced changes in facial contour. In summary, volumizing thread offers a minimally invasive alternative with fewer side effects for midface rejuvenation.

Molecularly imprinted beads based on modified cellulose hydrogel:A novel solid phase extraction filler for specific adsorption of camptothecin

Traditional solid phase extraction (SPE) suffers from a lack of specific adsorption. To overcome this problem, a combination of adsorption method and molecular imprinting technology by polydopamine modification was proposed to realize specific recognition of target compounds in SPE, which is of great significance to improve the separation efficiency of SPE. Cellulose hydrogel beads were prepared by dual cross-linking curing method and modified with polydopamine to make them hydrophilic and biocompatible. Subsequently, cellulose hydrogel-based molecularly imprinted beads (MIBs) were synthesized by surface molecular imprinting technology and used as novel column fillers in SPE to achieve efficient adsorption (34.16 mg·g−1) with specific selectivity towards camptothecin (CPT) in 120 min. The simulation and NMR analysis revealed that recognition mechanism of MIBs involved hydrogen bond interactions and Van der Waals effect. The MIBs were successful used in separating CPT from Camptotheca acuminata fruits, exhibiting impressive adsorption capacity (1.19 mg·g−1) and efficient recovery of CPT (81.54 %). Thus, an environmentally friendly column filler for SPE was developed, offering a promising avenue for utilizing cellulose-based materials in the selective separation of natural products.

Carbon slow-release and enhanced nitrogen removal performance of plant residue-based composite filler and ecological mechanisms in constructed wetland application

Stable carbon release and coupled microbial efficacy of external carbon source solid fillers are the keys to enhanced nitrogen removal in constructed wetlands. The constructed wetland plant residue Acorus calamus was cross-linked with poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) to create composite solid carbon source fillers (Ac-BDPs). The study demonstrated the slow release of carbon sources from Ac-BDPs with 35.27 mg/g under an average release rate of 0.88 mg/(g·d). Excellent denitrification was also observed in constructed wetlands with Ac-BDPs. Moreover, the average removal rate of nitrate nitrogen (NO3−-N) was increased by 1.94 and 3.85 times of the blank groups under initial NO3−-N inputs of 5 and 15 mg/L, respectively. Furthermore, the relatively high abundances of nap, narG, nirKS, norB, qnorZ and nosZ guaranteed efficient denitrification performance in constructed wetlands with Ac-BDPs. The study introduced a reliable technique for biological nitrogen removal by using composite carbon source fillers in constructed wetlands.

Xylan‑Assisted construction of anisotropic aerogel for pressure sensor

Currently, aerogels are promising for wearable pressure sensors due to their superior flexibility and high sensitivity. However, uniform dispersion of conductive solid filler is a critical step in the preparation process. Herein, xylan with good amphiphilicity was obtained by hydroxypropylsulfonation under mild reaction conditions, which is accepted as a dispersant for multi-walled carbon nanotubes (MWCNTs) in water. The hydroxypropylsulfonated xylan (HSX) exhibited a satisfactory dispersion efficiency reached to 97.8 %. After standing for 20 days, there are still 76 % of MWCNTs stabilized in the dispersion. Then, the ultralight, flexible and superstable anisotropic aerogels were prepared by freeze-casting technology. The obtained aerogel reveals excellent mechanical performance, with a great compressibility (undergoing a strain of 70 %) and elasticity (91.8 % height retention after 100 cycles at a strain of 20 %). As a proof of concept, the HSX/MWCNTs aerogel is utilized to construct a pressure sensor, which exhibit high sensitivity (S = 2.17 kPa−1) and impressive responsiveness to human motions. This work demonstrates a promising flexible electronic material for wearable electronics, electronic skin, and human motion monitoring.

Molecular dynamics simulation of bonding role of cyclic borate ester in improving mechanical properties of the HTPB propellant

Excellent mechanical properties are the fundamental requirement for the practical application of solid propellants. However, solid oxidant fillers such as hexahydro-1,3,5-trinitros triazine (RDX) seriously weaken the mechanical strength of the propellant due to poor adhesion with the binder matrix. In this work, novel cyclic borate ester (CBE) bonding agents with long-chain alkyl moiety were designed by the molecular dynamics (MD) method to improve the unfavorable interfacial bonding effect. The interface models, which consist of RDX substrate and binder matrix where hydroxyl-terminated polybutadiene (HTPB) crosslinked with curing agents, were constructed to reveal the interface enhancement mechanism by CBE bonding agents. The results indicate that the designed CBE bonding agents with appropriate solubility parameters (SPs) can migrate from the binder matrix to the RDX surface. Besides, CBE bonding agents exhibit strong interaction with RDX compared to the binder matrix due to the formation of hydrogen bonds. Finally, the simulated tensile tests with two tensile modes showed that CBE bonding agents can enhance the interfacial strength and reduce stress softening rates by the calculation of debonding work. Moreover, this improvement can be controlled by adjusting the chain length of CBE bonding agents. The results obtained in this work deepen the understanding of the interfacial strengthening mechanism of bonding agents for solid propellants and provide a framework for designing high-performance bonding agents based on the MD method.