Core-shell Composite Particles Research Articles

Preparation and Mechanical Properties of Core-Shell PS&CeO2 Composite Abrasive Particles.

Core-shell composite abrasive particles are a topic of great interest in surface finishing. It is important to explore the preparation technology and performance parameters associated with them. In this paper, a core-shell composite abrasive particle made of polystyrene and cerium oxide (PS&CeO2, CSPC), which is rigid on the outside and flexible on the inside, is proposed. The microstructure, physical phase characteristics, and mechanical properties of the inner core and composite abrasive particles are investigated. PS microspheres and CSPC composite abrasive particles with different structural features were prepared through a series of experiments, morphological observations, and physical and chemical characterization experiments. Their microstructures and physical phase properties were investigated. The indentation load curves of the PS microspheres and CSPC composite abrasive samples were measured by using an atomic force microscope. The analysis focused on the effects of various dimensional and structural parameters on the modulus of elasticity of both PS microspheres and CSPC composite abrasive particles. The analysis shows that the experimentally prepared PS microspheres have good dispersion, a smooth surface, and a uniform particle size distribution. The prepared CSPC composite abrasive particles are regular spheres with rough, rice-like surfaces, low modulus of elasticity, and overall nonrigid and soft elastic properties. The results of this paper can provide a guide for the preparation technology, performance regulation, and application of polymer microspheres and core-shell composite abrasive particles in CMP.

Rapid coating of polyamide, polyurea, and polythiourea on metal–organic framework surfaces

Well-defined metal–organic framework (MOF)@polymer core–shell composite particles with polyamide, polyurea, and polythiourea as the shell layer have been constructed for the first time using non-solvent-induced surface-aimed polymerization. This surface polymerization method utilizes non-solvent-induced phase separation to concentrate and direct monomers onto MOF particle surfaces, thus completing the coating process in less than 5 min. The generalizability of this method has been demonstrated with different MOFs. Coating MOF particles with any of the three polymers can effectively improve the stability of the MOF in harsh chemical environments. When used for heavy metal removal, polythiourea-coated composite particles (MOF@HDA-PDTC) exhibited a drastically improved Hg(II) removal rate and full utilization of the thione groups for Hg(II) binding compared to their neat polymer counterparts. This highlights the unique benefit of this core–shell architecture for the optimization of diffusion.

Enhanced flame retardancy and thermal stability in flexible polyurethane foam through synergistic core-shell structured DBDPE@PMA particles

This research presents the synthesis of core–shell structured flame retardant particles, DBDPE@PMA, which combines the flame-retardant and toughening functions. These particles utilize decabromodiphenyl ethane (DBDPE) as the core and a copolymer of methyl methacrylate and acrylic acid (MMA-AA) as the shell, which are created via emulsion polymerization. The process involved an initial reaction of DBDPE@PMA with isocyanate, followed by foaming with polyether polyol to fabricate flame retardant, and the flexible polyurethane foam (P/D-FPUF) was thermally insulated. The study examined the influence of DBDPE@PMA on the flame retardancy properties of flexible polyurethane foam. Scanning electron microscopy confirmed the encapsulation of DBDPE by the polymer, resulting in a core–shell composite particle. The interaction between the carboxylic groups (–COOH) on the DBDPE@PMA shell and isocyanate enhanced the interfacial bonding, thereby increasing the foam's apparent density and ensuring better integration with the polyurethane matrix. However, DBDPE@PMA had aggregates on the foam matrix bubble holes, resulting in uneven bubble holes. DBDPE@PMA markedly improved the flame retardancy and thermal stability of the foam, compared to both pure polyurethane and foam containing solely DBDPE (10D-FPUF). The oxygen index value of the foam with 20% DBDPE@PMA (20P/D-FPUF) reached 33.6%, with UL-94 horizontal and Vertical burning level tests achieving the highest classifications. The char residue after thermal degradation increased significantly from 1.93% in pure foam to 5.06%. While the smoke density level rose, the duration to peak smoke density was prolonged to 78 s, offering an enhanced margin for evacuation during the initial stages of a fire.

Sodium alginate/chitosan-coated TiO2NPs hybrid fiber with photocatalytic self-cleaning property, UV resistance and enhanced tensile strength

SA/CS-coated TiO2NPs hybrid fibers with photocatalytic self-cleaning properties, UV resistance and enhanced tensile strength were successfully prepared by adding CS-coated TiO2NPs to SA matrix. The FTIR and TEM results demonstrate the successful preparation of CS-coated TiO2NPs core-shell structured composite particles. SEM and Tyndall effect results showed that the core-shell particles were uniformly dispersed in the SA matrix. When the content of Core-shell particles increased from 0.1 to 0.3 wt%, the tensile strength of SA/CS-coated TiO2NPs hybrid fibers increased from 26.89 to 64.45 % compared with SA/TiO2NPs hybrid fibers. The SA/CS-coated TiO2NPs hybrid fiber (0.3 wt%) exhibits excellent photocatalytic degradation performance, achieving a 90 % degradation rate for the RhB solution. And the fibers also exhibit outstanding photocatalytic degradation performance towards various dyes and stains commonly encountered in daily life, including methyl orange, malachite green, Congo red, coffee and mulberry juice. The UV transmittance of the SA/CS-coated TiO2NPs hybrid fibers decreased significantly from 90 % to 75 % with the increase in core-shell particle addition, and correspondingly, the UV absorption capacity increased. The SA/CS-coated TiO2NPs hybrid fibers prepared lay the groundwork for potential applications in various fields, including textiles, automotive engineering, electronics and medicine.

Bio-inspired hydrophobic copper stearate coating to reduce the moisture absorption of fine-grained ammonium perchlorate and improve safety and thermal decomposition performance

Inspired by the superhydrophobic phenomenon in nature, multifunctional fine-grained ammonium perchlorate (F-AP)@copper stearate (CS) core-shell structure composite particles were designed by the in-situ liquid deposition method. Scanning electron microscopy (SEM) characterization proved that raw AP was refined, and a series of in-depth characterizations proved that the core-shell structure of F-AP@CS was prepared. Due to the core-shell F-AP@CS bionic hydrophobic structure and low surface energy, when the CS content is 5%, the moisture absorption rate was reduced from 0.54% to 0.03% within 72 h, and the water contact angle was increased to 126.6°. At room temperature, the safety performance of F-AP is effectively improved because of the barrier effect and melting heat absorption of the CS shell, the impact sensitivity (H50) of F-AP@CS (wt = 5%) was increased from 27.2 cm to 54.2 cm, and the friction sensitivity was reduced from 96% to 0%. As the temperature rises, CS will decompose into CuO with extremely high catalytic activity at 267 °C, the high temperature decomposition peak of F-AP@CS (wt = 5%) was advanced from 423.3 °C to about 305.9 °C, and speculate the mechanism of CS catalyzing the decomposition of AP.

Polymer@SiO2 Core–Shell Composite Particles: Preparation and Application

In recent years, core–shell composite particles with organic polymer as the core and inorganic SiO2 as the shell have attracted widespread attention and prompted robust scientific endeavors. The encapsulation of SiO2 can endow the polymer core with a variety of important properties, and is of great significance for the synthesis of multi–functional materials, having favorable application prospects in coating, polishing, medical, optical, magnetic, lubrication and other fields. In this paper, the recent advances in the preparation of core–shell polymer@SiO2 composite particles are reviewed. From the perspective of interface bonding mechanisms between the core and the shell, this paper mainly focused on the following five aspects: Pickering stabilization, acid–base interaction, charge interaction, bridging of coupling agent, hydrogen bonding, and other actions. Additionally, applications of core–shell polymer@SiO2 particles are also discussed. It is expected that this article can provide scientific guidance for the preparation of polymer@SiO2 core–shell particles, further enriching their species and broadening their applications.

The preparation, characterization, and application of porous core–shell composite particles produced with laboratory-scale spray dryer

Objective To prepare porous core–shell composite particles (PCPs) in order to improve the flowability and compactibility of powder materials for direct compaction (DC), as well as the dissolution of tablets. Significance The results obtained are meaningful to boosting the development and further research of PCPs on DC. Methods: In this study, hydroxypropyl methylcellulose (HPMC E3) and polyvinylpyrrolidone (PVP K30) were selected as shell materials, the Xiao Er Xi Shi formulation powder (XEXS) was used as the core materials, ammonium bicarbonate (NH4HCO3), and sodium bicarbonate (NaHCO3) were employed as pore-forming agent. Using co-spray drying method to prepare composite particles (CPs). Then, the physical properties and comparison between different CPs were characterized comprehensively. Finally, the different CPs were directly compacted as tablets to explore the effect on the dissolution behavior of DC tablets, respectively. Results (i) The XEXS PCPs were prepared successfully by co-spray drying, and the yield of PCPs is almost 80%; (ii) The TS values of PCP-X-P-Na, PCP-X-P-NH4, PCP-X-H-Na and PCP-X-P-Na were 5.70, 7.56, 3.98, and 6.88 times higher than that of raw material (X); (iii) The disintegration time of PCPs tablets decreased 10–25% when compared with CPs tablets; (iv) The values of Carr’s index (CI), Hausner ratio (HR), Caking strength (CS), and Cohesion index (CoI) of PCP-X-H-NH4 were 19.16%, 19.29%, 40.14%, and 6.39% lower than that of X, respectively. Conclusions The PCPs prepared by co-spray drying did improve the flowability and compactibility of powder, as well as the dissolution of tablets.

Synthesis of Al2O3/SiO2 core–shell composite abrasives toward ultrasmooth and high-efficiency polishing for sapphire wafers

A novel Al2O3/SiO2 core–shell composite abrasive was successfully synthesized via a facile sol–gel strategy and utilized to promote the surface quality and polishing efficiency of sapphire wafer. The silica shell with dense and amorphous structure was successfully coated on Al2O3 core. Its synthesis mechanism was discussed deeply, and good dispersibility and uniform particle size were obtained. The acquired core–shell composite particles were employed for the planarization machining of sapphire wafer. Results show that the decrease in surface roughness of Al2O3/SiO2 core–shell composite abrasives during polishing is more than 20.2% of that of pure Al2O3 abrasives, the material removal rate is more than 5.1% of that of pure Al2O3 abrasives, and the residual stress of the sapphire wafer finished by composite abrasives is decreased by approximately 40%. These results demonstrate that the Al2O3/SiO2 core–shell composite abrasives provide a more excellent polishing performance for the sapphire wafer, resulting in smoother and scratch-free surface with a higher material removal rate compared with pure Al2O3 abrasives. On the basis of the reaction product analysis and elastic-plastic micro-contact mechanics, the reasons for the improvement of polishing performance were revealed in terms of chemical corrosion and mechanical abrasion.

Succinylated whey protein isolate-chitosan core–shell composite particles as a novel carrier: Self-assembly mechanism and stability studies

Single protein [whey protein isolate (WPI) or succinylated whey protein isolate (SWPI)] and composite particles of proteins with chitosan (CS) were tested for their ability to encapsulate and protect curcumin (CUR). Combining protein and CS resulted in changes in zeta-potential and surface hydrophobicity, particularly in the SWPI-H (high degree of succinylation, 90 %) and CS composite particle (H-CS). Furthermore, the secondary and tertiary structures were dramatically altered using Fourier transform infrared (FTIR), circular dichroism (CD), and X-ray diffraction (XRD). Scanning electron microscopy (SEM) and atomic force microscope (AFM) analyses revealed that H-CS exhibited a soft core-rigid shell morphology due to electrostatic interactions, hydrophobic interactions, and H-bond interactions. Fluorescence quenching results demonstrated that H-CS had a higher binding constant (K, 1.69 ×104 M−1) and encapsulation effectiveness (EE, 88.3 %) of CUR. Because of increased binding sites and steric hindrance, CUR was stabilized more effectively in H-CS in photostability and thermostability tests,. These results show that SWPI-CS composite particles can be utilized to build a protection system for water-insoluble nutritional supplements.

Deposition of Vertically Aligned Ag/Ag2 S Nanoflakes on EGaIn Particles for Humidity Sensing.

Liquid metals, which possess both good electrical conductivity and liquid-like processability, have drawn much attention recently. They are also capable of acting as synthesis templates to guide the deposition of other functional materials. Herein, through an in-situ galvanic replacement reaction assisted by ultrasonication, core-shell EGaIn/Ag particles composed of EGaIn cores and vertically aligned Ag nanoflakes as shells were prepared; they were further sulfurized to yield ternary EGaIn/Ag/Ag2 S core-shell composite particles. A humidity sensor based on EGaIn/Ag/Ag2 S particles showed much higher sensing response than EGaIn and EGaIn/Ag. Such superior performance could be attributed to the n-type semiconducting character of Ag2 S allowing it to receive electrons from water molecules at low humidity, and its highly hydrophilic surface allowing it to absorb more water molecules at higher humidity so as to enable the formation of ion-conductive paths.

Multifunctional Fe3O4@Ag@TiO2-xNx core-shell composite particles for dye adsorption and visible-light photocatalysis

This study prepares Fe3O4@Ag@TiO2 (FAT) particles via a solvothermal route, then thermally treats the particles over a temperature range from 300 to 500 °C in flowing nitrogen atmosphere to form Fe3O4@Ag@TiO2-xNx (x = 0.056 to 0.15) (FATN) core-shell composite particles. The FATN particles comprise an outermost TiO2-xNx shell of about 20–50 nm in thickness, a Brunauer-Emmett-Teller surface area of 103.2–152.5 m2/g, and a Barrett-Joyner-Halenda pore size of 12.9–30.2 nm. The particles show dye adsorption and visible-light photocatalysis against a model methylene-blue (MB) dye in water. For the FATN particles being treated at 400 °C, they show a dark adsorption of 54.8% and an additional visible-light photodegradation of 25.1% when using a dyed wastewater with an initial MB concentration of 5 × 10-6 M. This compares favorably to those being treated at other nitridation temperatures. The 500 °C-treated FATN particles yet exhibit a dark adsorption of 99.1% against the MB solution. Use of an external magnet can facilely recycle the composite particles. The recycled particles remain greater than 72% of their initial MB removal capability after use of five times. The intermediate Ag nanolayer can release Ag ions to the surrounding water medium through the mesoporous shell channel. The time-dependent Ag release appears to follow the Voigt-Maxwell model and reaches 0.764 ppm after 48 h, suggesting a long-time releasing efficacy.

Shell-to-core ratio dependence on modulating interactions between core-shell composite nanoparticles at an air-aqueous interface

The current study examined the shell-to-core ratio (λ) dependence on modulating interactions between core-shell composite particles (CPs) at the air-aqueous interface. The CPs were prepared by physical adsorption of poly(vinylpyrrolidone) (PVP) on the surface of silica nanoparticles (NPs). The λ value increases with increasing PVP adsorption density and PVP molecular weight. The resulting CPs are referred to as CPs8, CPs40, CPs360, and CPs1300 respectively, depending on the molecular weight of PVP that being used. The 8 kDa PVP shell is thin, and the CPs8 behave more like hard spheres at the interface. Hence, great shear and compressional elasticities of the CPs8-laden interface were measured. Whereas, higher values of λ (thicker PVP shells) induce a stronger steric barrier, which dominates the self-assembly of the CPs and modulates the microstructure of the CPs-laden interface into more complex and non-hexagonal phases (i.e. anisotropic chains), e.g. for the CPs360 and CPs1300 cases. The enhanced steric repulsion between the polymer shells makes significant contributions in building up the surface pressure before the solid particle cores being sufficiently compressed, which reduces the apparent particle surface coverage, lubricates the CPs-CPs interaction, and facilitates the rearrangement of the CPs under compression and shear, resulting in interfacial films with weak viscoelasticity. The CPs40, however, showed a transition behavior between the “hard” CPs8 and the “softer” CPs360 and CPs1300 at the air-aqueous interface.

Research on preparation of nano-Sb2O3@Br-VERs core-shell composite particles

Nanoparticles with core-shell structure provide a new potential technology to improve the efficiency of flame retardants. Using nanometer antimony trioxide particles (nano-Sb2O3) as matrix material and brominated bisphenol-A epoxy vinyl ester resin (Br-VERs) diluted by toluene (PhMe) or styrene (ST) as the coating material, PhMe-nano-Sb2O3@Br-VERs and ST-nano-Sb2O3@Br-VERs core-shell composite particles were prepared by electromagnetic stirring method. The results show that Br-VERs can successfully coat on the surface of nano-Sb2O3, thus forming core-shell composite particles with crystalline nano-Sb2O3 as the core and amorphous Br-VERs as the shell. The thickness of Br-VERs shell of PhMe-nano-Sb2O3@Br-VERs composite particles is between 9.5 nm and 15.5 nm, and the shell’s mass fraction is 20.8% in the composite particles. The thickness of Br-VERs shell of ST-nano-Sb2O3@Br-VERs composite particles is between 5.5 and 9.5 nm, and the shell’s mass fraction is 3.8%. The mass of Br-VERs shell of PhMe-nano-Sb2O3@Br-VERs composite particles is 5.47 times that of ST-nano-Sb2O3@Br-VERs composite particles, which indicates PhMe used as the diluent for Br-VERs has a better effect than that of ST used as the diluent.

Electrophoresis of soft particles with hydrophobic inner core grafted with pH-regulated and highly charged polyelectrolyte layer.

Electrophoresis of core-shell composite soft particles possessing hydrophobic inner core grafted with highly charged polyelectrolyte layer (PEL) has been studied analytically. The PEL bears pH-dependent charge properties due to the presence of zwitterionic functional groups. The dielectric permittivity of the PEL and bulk aqueous medium were taken to be different, which resulted in the ion-partitioning effect. Objective of this study was to provide a simple expression for the mobility of such core-shell soft particles under Donnan limit where the thickness of the PEL well exceeds the electric double layer thickness. Going beyond the widely used Debye-Hückel linearization, the nonlinear Poisson-Boltzmann equation coupled with Stokes-Darcy-Brinkman equations was solved to determine the electrophoretic mobility. The derived expression further recovers all the existing results for the electrophoretic mobility under various simplified cases. The graphical presentation of the results illustrated the impact of pertinent parameters on the electrophoretic mobility of such a softparticle.

Microstructure and mechanical properties of casting Al-3Li-2Mg-1Zn-0.1Zr alloys modified by Sc additions

In the present study, microstructure and mechanical properties of casting Al-3Li-2Mg-1Zn-0.1Zr alloys modified by Sc additions have been investigated. As-aged Al-3Li-2Mg-1Zn-0.2Sc-0.1Zr alloy possesses a desirable comprehensive mechanical performance. The YS, UTS and El reach 253 MPa, 406 MPa and 7.4% respectively. With the addition of Sc, a more than 50% reduction in the grain size was achieved by the promoted heterogeneous nucleation on primary Al3(Sc, Zr) phases and the grain growth resistance was enhanced by the Zener pinning. After the heat treatment, core-shell composite particles precipitated from the matrix. The shell consists entirely of Al3Li phases. In contrast, both Al3(Sc, Zr) and Al3Sc cores can be observed in the Sc-containing alloys. Increasing the Sc content from 0.1 wt% to 0.2 wt%, the mean radius of cores increases, while the mean width of shells and the number density of particles seem not to be affected. With the passage of ageing time, the coarsening of composite particles occurred, though the dimension of the core remained almost constant. The kinetics follows the KV model and the exponent (n−1) is about 0.11, which is lower than the expected value (0.33) probably due to the unreached quasi-steady-state at the present low temperature.

Facile One-Step Metal-Organic Framework Surface Polymerization Method.

A simple one-step approach that only uses commercially available small-molecule reagents was developed for the construction of metal-organic framework (MOF)@polymer core-shell composite particles. Here, the MOF particles were incorporated into a typical reversible addition-fragmentation chain-transfer (RAFT) polymerization solution containing a solvent, a chain-transfer agent, an initiator, and a monomer mixture with at least one hydrogen-bond-donating monomer such as 2-hydroxyethyl methacrylate or acrylic acid. The elongation of polymer chains during polymerization gradually increases MOF/polymer interfacial interaction and eventually results in the adsorption of a random copolymer onto the MOF surface through hydrogen-bond cross-linking and MOF/polymer interfacial interaction. The continuous growth of the polymer leads to a uniform polymer coating on the MOF. Benefiting from the tacky polymer surface, these well-defined MOF@polymer composite particles can be further assembled into highly ordered monolayer composite thin films either alone or with an additional polymer matrix through the Langmuir-Blodgett technique.

A case study of PTFE@SiO2 core-shell solid lubricant

In this paper, the wear and transfer behaviors of polytetrafluoroethylene@silica (PTFE@SiO2) core-shell composite particles filled epoxy resin (PTFE@SiO2-EP) coating during the sliding were studied in detail. The main results indicated that: firstly, the addition of PTFE@SiO2 particles can result in favorable plastic deformation on the worn surface; secondly, the morphology of PTFE@SiO2 particles in-situ changes from pressed to broken to flattened, and the average friction coefficient, wear rate as well as the transfer film thickness of the PTFE@SiO2-EP coating all conform to the following regularity: run-in period > steady-state period > transition period. Besides, except that FeF2 is not contained in the transition period, the compositions of the transfer film are basically unchanged during the whole friction process, which all consist of PTFE, ploy (methylmethacrylate-co-3-(trimethoxysilyl) propylmethacrylate) (P(MMA-co-MPS)), SiO2, EP and FeF2. Additionally, no wear debris is observed during the whole sliding. It is expected that this study can provide instructive scientific guidance for the lubrication behaviors of soft@hard core-shell additives, and further enrich the tribological theories of solid lubricants with core-shell structure.

Effect of core hydrophobicity on the electrophoresis of pH-regulated soft particles.

We propose a theoretical study on the electrophoresis of core-shell composite soft particles considering the effect of hydrodynamic slip length of the hydrophobic inner core. The surface of the inner core as well as the soft polymeric shell bear zwitterionic functional groups and the charged conditions depend on the nearby micro-environment. Within a low potential and weak electric field framework, the mathematical equations of the generalized electrokinetic theory for soft surfaces are solved analytically subject to appropriate boundary conditions, and a general electrophoretic mobility expression in an integral form involving the pH-dependent electrostatic potential is derived. With the help of suitable numerical schemes, electrophoretic mobility can easily be obtained. The effect of hydrophobicity of the inner core on the electrophoretic mobility of pH-regulated soft particles is illustrated for a wide range of pertinent parameters.

Effect of Silica Size and Content on Superamphiphobic Properties of Silica-Fluoropolymer Core-Shell Coatings.

We present a facile approach to fabricate superamphiphobic surfaces by spray coating silica-fluoropolymer core-shell particles without substrate pretreatment with an additional binder resin. A series of SiO2@poly(1H,1H,2H,2H-heptadecafluorodecyl methacrylate) (SiO2@PFMA) core-shell particles with core particles of different sizes were prepared via thiol-lactam initiated radical polymerization (TLIRP). The surface of each SiO2 particle with an average particle size of 12, 80, 150, and 350 nm was modified with (3-mercaptopropyl) trimethoxysilane and used as a seed for TLIRP. The SiO2@PFMA particles with various SiO2 sizes and contents were coated on aluminum substrates by a spray gun and then thermally treated to form a stable, rough composite layer. During the spray coating, the core-shell particles were aggregated by rapid evaporation of the solvent and then irregularly adhered to the substrate resulting in hierarchical structures. In the case of SiO2@PFMAs with low SiO2 contents, the roughness created mainly by the polymer shell disappeared during heat treatment. However, the substrates coated with SiO2@PFMAs with high SiO2 contents maintained the roughness even after heat treatment. The core-shell particles prepared with 12 nm SiO2 formed a stable superamphiphobic surface. The water/hexadecane contact and sliding angles on an aluminum plate coated with SiO2@PFMA, prepared using 12 nm silica at 46 wt% silica content (12 nm-SiO2(46)@PFMA), were 178.5°/159.2° and 1°/7°, respectively. The cross-cut tape test showed that adhesion between the 12nm-SiO2(46)@PFMA and the aluminum substrate was classified as 5B. A glass surface spray-coated with the core-shell composite particles exhibited transparent superhydrophobicity and translucent superamphiphobicity by controlling the concentration of the coating solution.

The Fundamental and Functional Property Differences Between HPMC and PVP Co-Processed Herbal Particles Prepared by Fluid Bed Coating.

Core-shell composite particles (CPs) are the most preferred choice for direct compaction (DC), but their application in herbal tablets is limited. Hydroxypropyl methylcellulose (HPMC) and polyvinylpyrrolidone (PVP) are usually employed as the shell materials, but there are few, if any, researches exploring the different effects of HPMC and PVP on the properties of herbal CPs. In this study, the CPs containing HPMC (CP X-H) and CPs containing PVP (CP X-P) were prepared based on herbal powders (X). Their physical properties were characterized comprehensively. The differences in properties between CP X-H and CP X-P were explored, and their mechanism analysis was also performed profoundly. The results demonstrated that (i) CP X-H and CP X-P exhibited similar flowability; (ii) CP X-H generally exhibited better compactibility, larger particle size, and more uniform particle size distribution, and lower bulk density, tap density, and hygroscopicity than CP X-P; (iii) compared with the tablets produced with CP X-P, ones with CP X-H exhibited similar weight variation (%), lower friability, and longer disintegration time. The mechanism analysis manifested that the differences in physical properties between HPMC and PVP were the important and fundamental factors, which led to the differences in structure and surface morphology of particles, and in fundamental properties of CPs. These findings are beneficial to the development of herbal core-shell CPs for DC.