MgO Composite Research Articles

Influence of Chloride Ion Concentration on Corrosion Behavior of WC–MgO Composite

The influence of chloride ion (Cl−) concentration on the corrosion mechanism of WC–MgO composites has been studied in this work. The results suggest that the corrosion resistance of WC–MgO composite decreases first and then increases with the increase in Cl− concentration. Solution conductivity and dissolved oxygen content are the main influence factors. The solution conductivity determines the charge transfer process, and the dissolved oxygen determines the cathodic oxygen absorption reaction. The corrosion characteristic is typical pitting corrosion. Meanwhile, the corrosion mechanism contains an oxidation process of the WC matrix and the dissolution destruction of the MgO toughening phase. The formation of the WO3 corrosion layer hinders the general corrosion to protect the inner material. However, the dissolution of MgO induces the initiation of pitting. The local alkaline caused by MgO dissolution promotes the dissolution of the WC matrix, which leads to the expansion of pitting.

In vitro and vivo biocompatibility and degradability of low-alloyed Mg-Zn-Ca-MgO composite as bone repair biomaterials

Abstract Magnesium alloys have gained attention as biodegradable bone repair biomaterials. Unlike non-biodegradable materials like titanium and tantalum, biodegradable implants offer advantages in promoting bone healing and minimizing chronic inflammatory reactions. However, the impact of the implant's degradation on the osteogenic environment remains a concern. The Mg-Zn-Ca-MgO composite, being biocompatible and containing osteogenic ions, is a promising candidate. This study assesses the degradability and in vitro/in vivo biocompatibility of two Mg-Zn-Ca-MgO composites with varying degradation rates. The Mg-1Zn-0.2Ca-1.0MgO composite was prepared, and leaching solutions were created following standard protocols. MC3T3-E1 cell cultures were conducted to assess cell toxicity, alkaline phosphatase (ALP) staining, cytoskeleton morphology, and osteogenic protein expression. In vivo biodegradation and bone regeneration capacity were evaluated in rat femoral condyles. Benefiting from the more protective corrosion product layer on the surface, the ultra-fine grained (UFG) composite showed better corrosion resistance and lower Mg2+ release than the coarse-grained (CG) composite. UFG material exhibited higher cell viability, cytoskeleton integrity, ALP secretion, and osteogenic protein expression. In vivo, UFG composites led to greater bone regeneration and exhibited excellent biocompatibility. The UFG Mg-Zn-Ca-MgO composite demonstrates enhanced biocompatibility, corrosion resistance, and bone regeneration potential. This study highlights the importance of controlling Mg ion release for optimal bone healing in biodegradable materials.

Dy2O3–MgO composite ceramics: Fabrication and properties

An IR-transparent magneto-optical Dy2O3–MgO compositeceramics was fabricated by vacuum hot pressing of glycine-nitrate self-propagating high-temperature synthesized nanopowders. Composites significantly outperform dysprosium sesquioxide ceramics in terms of thermal conductivity and mechanical properties.The HV1 microhardness of the Dy2O3–MgO composite is 9.9 GPa and the fracture toughnessKIC, calculated by the Palmquist method, is 1.7 MPa m½. The thermal conductivity of the composite was measured in the range of 50–300 K and is 10.6 W/(m K) at room temperature. The transmittance of 1.5 mm thick Dy2O3–MgO sample is about 70 % in the wavelength range ∼2.1–2.2 μm and more than 80 % in the range ∼3.6–6.5 μm, which is close to the theoretical value for dysprosium sesquioxide.The value of Verdet constant of Dy2O3–MgO composite ceramics is 7.0 ± 0.3 rad/(T∙m)at 1940 nm.

A hybrid mesoporous composite of SnO2 and MgO for adsorption and photocatalytic degradation of anionic dye from a real industrial effluent water.

Water pollution by synthetic anionic dyes is one of the most critical ecological concerns and challenges. Therefore, there is an urgent need to find an efficient adsorbent and photocatalyst for dye removal. In the present study, we aimed to fabricate a hybrid mesoporous composite of spongy sphere-like SnO2 and three-dimensional (3D) cubic-like MgO (SnO2/MgO) as a promising adsorbent/photocatalyst to remove the anionic sunset yellow (SSY) dye from real wastewater at neutral pH conditions. The as-synthesized SnO2 and MgO composite was investigated using XRD, SEM, EDX, TEM, XPS, BET, and zeta potential. The experimental study of the SSY removal using SnO2/MgO composite was performed at different conditions, such as pH, stirring time, dose, and temperature. More than 99% of 10 mg/L SSY was effectively adsorbed from aqueous solution using 40 mg of SnO2/MgO composite at pH 7 and a stirring time of 60 min. The SSY adsorption behavior was well fitted by pseudo-second order and the Langmuir model, indicating that the SSY was chemisorbed to the composite-active sites as a monolayer. On the other hand, photocatalytic degradation process exhibited better results in terms of speed of removal and used quantity of photocatalyst, where 20 mg of SnO2/MgO composite can be used to remove > 99% of SSY dye within 30 min. Mechanism of SSY adsorption and photocatalytic degradation was discussed. In addition, elution experiments demonstrated that the SnO2/MgO composite as an SSY adsorbent could be reused for nine cycles without considerable reduction in the SSY adsorption efficiency. Therefore, this work exhibited that the mesoporous SnO2/MgO composite can be considered an effective adsorbent/photocatalyst to remove SSY dye from real industrial effluent water at neutral pH conditions.

Mechanical and corrosion properties of Mg–MgO and Mg–Al2O3 composites fabricated by equal channel angular extrusion method

Equal channel angular extrusion (ECAE) has shown great potential for the consolidation of powdered materials. In the present article, the mechanical and corrosion properties of Mg–MgO and Mg–Al 2 O 3 composites produced by the ECAE method were studied. Pure magnesium reinforced with 0, 10, 20, and 30 ​vol percentages of MgO and Al 2 O 3 particles were hot consolidated at 600 ​MPa in an ECAE die without prior cold compaction or canning of the powders. Results indicated that the reinforcement content is directly proportional to the hardness, compressive strength, and corrosion resistance of the fabricated composites, while it has an inverse relationship with the relative density. The lowest relative density and the highest corrosion rate were obtained for the Mg+30%MgO composite samples, as opposed to the pure magnesium with the highest relative density and the lowest corrosion rate. Besides, composites reinforced with 30 and 20 ​vol percentages of alumina revealed the highest hardness and the highest compressive strength, which were 55% and 74% higher than that of the pure magnesium sample, respectively. Based on SEM and EDX analyses, it was shown that Mg–Al 2 O 3 samples had finer grain sizes compared to Mg–MgO composites. • ECAE was successfully implemented to fabricate Mg–MgO and Mg–Al 2 O 3 composites. • Hardness and strength are linearly related to the content of the reinforcements. • Mg–Al 2 O 3 showed remarkably higher strength and hardness compared to the Mg–MgO. • The corrosion rate of the Mg–Al 2 O 3 was lower than that of Mg–MgO.

Preparation of High‐Performance WC–MgO Composites by Spark Plasma Sintering

Herein, tungsten carbide (WC)–4.3 wt% MgO composite powders are synthesized by high‐energy planetary ball milling method and then consolidated by spark plasma sintering (SPS). Submicrometer WC–MgO composite powders are consolidated to obtain a nearly complete density of WC–MgO composites (99.15%). The nanosized MgO distributed along the WC grains in WC–MgO composite plays an important role of dispersion strengthening and achieving high flexural fracture strength of WC–MgO composites (1348 MPa). As the addition of MgO increases the interfacial strength, the fracture mode of WC–MgO composites is mainly a mixture of transgranular fracture and intergranular fracture. High value on Vickers hardness (1660HV) and fracture toughness (9.37 MPa m1/2) of WC–MgO are also observed due to the crack deflection and crack bridging. Binderless WC–MgO composites have similar properties to WC–Co and are expected to replace WC–Co hard metal for saving resources and reducing cost.

Sequential photocatalytic degradation of organophosphorus pesticides and recovery of orthophosphate by biochar/α-Fe2O3/MgO composite: A new enhanced strategy for reducing the impacts of organophosphorus from wastewater

Photocatalysis is regarded as one of the most promising techniques for degrading organophosphorus pesticides (OPs) from wastewater given its low-cost and environmental benignity. Yet, photocatalytic degradation of OPs is an incomplete process, since PO43− is produced after photocatalysis. Here, biochar-supported α-Fe2O3/MgO composite (BC-α-Fe2O3/MgO) is developed for sequential photocatalytic degradation of OPs and recovery of the produced PO43−. The degradation efficiency of N-phosphonomethyl iminodiacetic acid (NPA) by BC-α-Fe2O3/MgO based photocatalysis reaches 90.1% within 80 min, and the recovery ratio of the produced PO43− by BC-α-Fe2O3/MgO is as high as 82.3%. Besides, the as-prepared BC-α-Fe2O3/MgO used in this integrated photocatalysis and adsorption process maintain a high stability towards NPA degradation and PO43− recovery during five cycling experiments. The mechanistic study reveals that holes, •OH, and •O2– radicals generated in the photocatalytic process are responsible for NPA degradation. UV light can activate persistent free radicals on BC-α-Fe2O3/MgO surface, which provide O2 withelectrons for the generation of •O2– and subsequent yield of •OH. Moreover, the presence of α-Fe2O3 and MgO on the surface of biochar leads to the excellent P adsorption performance of BC-α-Fe2O3/MgO. This study opens new possibilities for the recovery of P resource from organophosphorus polluted wastewater.

Antibacterial activity of V- doped rod-like MgO crystals decorated with nanoflake layer

In present study, we report a V doping fabrication method for obtaining rod-like MgO crystals decorated with a nanoflake layer. This novel structure has only been minimally reported in literature. Pure MgO and Mg2V2O7–MgO composite materials were obtained by precipitation and impregnation methods, with vanadium added concentrations of 0–9%. The influence of V doping on crystal structure and particle morphology of MgO was investigated by scanning electron microscopy (SEM). X-ray diffraction (XRD) analysis demonstrated that MgO has a cubic structure, while X-ray photoelectron spectroscopy (XPS) revealed that V5+ exists on the surface of MgO. The specific surface areas and pore sizes of MgO composites were calculated by BET and BJH analysis. These techniques revealed that specific surface area and pore size of MgO increased due to vanadium doping. The antibacterial effects of Mg2V2O7–MgO composite materials against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were assessed using a bacterial killing/colony-forming unit (CFU) assay and bacteriostatic ring method. Our results demonstrate that V doping dramatically improved antimicrobial properties of MgO, with 7 mol% doping inducing the best antibacterial activity. The antibacterial mechanisms of Mg2V2O7–MgO composite material were also proposed.

Alkali Metal Nitrates Promoted MgO Composites with High CO2 Uptake for Thermochemical Energy Storage

Thermochemical energy storage (TCES) by means of reversible chemical reactions represents a promising strategy for harnessing renewable energy and recovering industrial waste heat. In this work, alkali metal nitrate promoted MgO composites were synthesized, and the MgO–CO2 working pair was suggested as an alternative candidate for harvesting intermediate-temperature industrial waste heat. However, it remains unclear how operating parameters would affect the heat storage density, and the long-term cycling stability of the alkali metal nitrate promoted MgO composites under harsh conditions close to practical application scenarios needs to be clarified. The objectives of this work are to expound the effects of operating parameters on TCES performance and to evaluate the long-term cycling stability of the alkali metal nitrate promoted MgO composites. With increasing NaNO3 content, the heat storage density of NaNO3–MgO increases dramatically first and then exhibits no significant change. With rising carbonation temperature, the heat storage density of the 10NaNO3–MgO composite increases first and then declines marginally, while it increases with the increasing CO2 partial pressure. Doping alkali metal nitrate eutectic mixtures adversely affects the heat storage density. 10NaNO3–MgO exhibits a high heat storage density of 2291 kJ/kg at 340 °C in 100% CO2. The 10NaNO3–MgO and 10(K–Na)NO3–MgO composites suffer a significant decline in heat storage density within 10 consecutive cycles, while 10(Li–Na)NO3–MgO retains good stability with a slight decrease of heat storage density from 1073 to 770 kJ/kg in 50% CO2. The desired 10(Li–Na)NO3–MgO is suggested as a promising material for TCES application.

High electromagnetic interference shielding effectiveness in MgO composites reinforced by aligned graphene platelets

ABSTRACTGraphene has been considered as an excellent filler to reinforce ceramics with enhanced properties. However, the uniform dispersion and controlled orientation of graphene sheets in a ceramic matrix have become major challenges toward higher performance. In this paper, we prepared MgO matrix composites with parallel graphene layers through the intercalation of the precursor into expandable graphite. We obtained a high electromagnetic interference (EMI) shielding effectiveness of ~30 dB, due to the multiple reflections and absorptance of electromagnetic waves between the parallel graphene layers. The hardness and strength of the MgO composite were also increased by introducing parallel graphene layers. All these properties suggest that the graphene/MgO composite represents a promising electromagnetic shielding material.

Preparation of Mg-Zr alloys through direct electro-deoxidation of MgO-ZrO2 in CaCl2-NaCl molten salt

The electro-deoxidation of MgO does not proceed efficiently due to the electrical insulation properties of MgO and large molar volume of metallic magnesium. In this experiment, an attempt was done to prepare Mg-Zr alloy from their oxides using the method of electro-deoxidation. The electrochemical mechanism of the deoxidation process of MgO, ZrO2 and MgO-ZrO2 composite was studied through cyclic voltammetry using metallic cavity electrode (MCE). There was an intermediate phase (Zr3O) in the reduction process of ZrO2. The electro-deoxidation of MgO occurred for MgO-ZrO2 composite in CaCl2-NaCl molten salt. Moreover, the electro-deoxidation of MgO was promoted by the addition of polyvinyl butyral (PVB). The formation of metal phase Mg was confirmed by XRD, EDS, Raman spectroscopy, and inductively-coupled plasma spectroscopy. The electro-deoxidation products showed significant differences with the concentration of PVB and the ratio between MgO and ZrO2. The electro-deoxidation of MgO and ZrO2 was favorable when the PVB concentration was 5.0% (wt.%). Pure metal phase of Mg-Zr alloys was formed when the molar ratio of MgO and ZrO2 was 1:2. The atomic fraction of Mg in the electrolytic product was ca. 28.0 mol.%. This work shows that MgO could be directly electro-deoxidized to Mg without the formation of intermediate phase oxide.

Enhanced degradation of sulfamethoxazole by a novel Fenton-like system with significantly reduced consumption of H2O2 activated by g-C3N4/MgO composite

Advanced oxidation processes (AOP) based on nonradicals have attracted growing attentions because nonradical systems require much less oxidants and have low susceptibility to radical scavengers. Herein, a novel Fenton-like system that utilizes nonradicals was explored. It was derived from g-C3N4/MgO activated H2O2, and can reduce the H2O2 stoichiometry from 0.94%−0.18% to 0.03%. Sulfamethoxazole (SMX), a widely used sulfonamide, was used as the model pollutant to evaluate the efficacy of the system. It was observed for the first time that organic pollutants can be degraded with singlet oxygen (1O2) through a nonradical pathway in the g-C3N4/MgOH2O2 system. The reduced H2O2 consumption was the net result of continuously-recycled H2O2 from the reactions between H2O2 and g-C3N4/MgO. Based on experimental results and theoretical calculations, the synthesis of g-C3N4 and MgO forms a N-Mg bond with strong ability to absorb electrons and the electron transfer of H2O2 to N-Mg bonding is accelerated, activation of H2O2 to generate 1O2. Experimental data showed that organic pollutants can be degraded rapidly over a wide pH range. Findings of this study point to a cyclical but stable Fenton-like system with reduced H2O2 requirement for cost-effective remediation and treatment of organic pollutants and toxic wastes.

Corrosion-Resistant Steel-MgO Composites as Refractory Materials for Molten Aluminum Alloys.

In this study, a novel metal matrix composite based on 60 vol% 316L stainless steel and 40 vol% MgO manufactured by powder metallurgy technology was developed. The corrosion resistance of the developed steel–MgO composite material against molten aluminum alloy AlSi7Mg0.3 was investigated by means of wettability tests and long-term crucible corrosion tests. The wettability tests were carried out using the sessile drop method with the capillary purification technique in a hot-stage microscope (HSM). Static corrosion tests were performed in molten aluminum alloy at 850 °C for 168 h to evaluate the impact of pre-oxidation of the composite surface on the corrosion resistance. The pre-oxidation of steel–MgO composites was carried out at 850 and 1000 °C for 24 h, based on preliminary investigations using thermogravimetry (TG) and dilatometry. The influence of the pre-oxidation on the composite structure, the corrosion resistance, and the phase formation at the interface between the steel–MgO composite and aluminum alloy was analyzed using SEM/EDS and XRD. The impact of the steel–MgO composite material on the composition of the aluminum alloy regarding the type, size, and quantity of the formed precipitations was investigated with the aid of ASPEX PSEM/AFA and SEM/EBSD. It was revealed that the pre-oxidation of the steel–MgO composite at 1000 °C induced the formation of stable MgO-FeO solid solutions on its surface, leading to a significant increase of long-term corrosion resistance against the liquid aluminum alloy.

Enhancement on high-temperature microwave absorption properties of TiB2–MgO composites with multi-interfacial effects

TiB2–MgO microwave absorbing materials with TiB2 as the absorber, MgO as the matrix are prepared by spark plasma sintering (SPS). The influences of commercial TiB2 content and sintering temperature on dielectric and microwave absorption (MA) properties are studied. Besides, to optimize the MA performance, TiB2–MgO composite containing TiB2 synthesized by the carbonthermal process is prepared. Meanwhile, its high-temperature dielectric and MA properties are investigated. Indeed, both the commercial TiB2 content and sintering temperature play key roles in dielectric and MA properties, as they reaching 8 wt% and 1400 °C, the composite presents the optimal MA performance. For composite with synthetic TiB2 as the absorber, the temperature has a positive effect on dielectric and MA properties. The enhanced high-temperature MA properties with minimum reflection loss (RLmin) of −52.11 dB at 1.6 mm under 500 °C and effective absorption bandwidth (EAB, RL < −5 dB) of 4.2 GHz at 1.4–1.6 mm under 800 °C are obtained, which is mainly attributed to the temperature-dependent interfacial polarization compared to the temperature-insensitive conductivity. The excellent mechanical properties (flexural strength = 212.48 MPa), thin absorbing layer (d < 2 mm), enhanced thermal stability and high-temperature MA properties indicate that the TiB2–MgO composites can be considered as new candidates for high-temperature structure microwave absorbing materials.

Highly stable M/NiO–MgO (M = Co, Cu and Fe) catalysts towards CO2 methanation

NiO–MgO nanocomposites are synthesized using solution combustion, sonochemical, and co-precipitation synthesis to understand the catalytic activity of CO2 methanation. Excellent particle size distribution was noticed with the sonochemical routed synthesis method, and the CO2 conversions are found to be better with the same synthesis protocol. Surface modifications in NiO–MgO composite were incorporated by doping M (M = Co, Fe, and Cu). The active catalysts are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to understand physical, structural properties and surface morphology of the nanocomposites. All catalysts showed excellent catalytic activity for the conversion of CO2 to methane and selectivity towards methane to be higher than 85%. However, 2%Co/NiO–MgO showed the lowest activation energy of about 43 ± 2 kJ mol−1 among other synthesized catalysts. The mechanism of CO2 methanation was investigated with the inputs from temperature programming reduction with H2 (H2-TPR), and temperature programming desorption with CO2 (CO2-TPD) studies. Detailed reaction mechanism and kinetics are investigated for all doped catalysts. M/NiO–MgO offered excellent stability up to 50 h reaction time with high CO2 conversions and CH4 selectivities.

Characterization and thermophysical properties of Zr0.8Nd0.2O1.9–MgO composite

The major drawback of zirconia-based materials, in view of their applications as targets for minor actinide transmutation, is their poor thermal conductivity. The addition of MgO, which has high thermal conductivity, to zirconia-based materials is expected to improve their thermal conductivity. On these grounds, the present study aims at phase characterization and thermophysical property evaluation of neodymium-substituted zirconia (Zr0.8Nd0.2O1.9; using Nd2O3 as a surrogate for Am2O3) and its composites with MgO. The composite was prepared by a solid-state reaction of Zr0.8Nd0.2O1.9 (synthesized by gel combustion) and commercial MgO powders at 1773 K. Phase characterization was carried out by X-ray diffraction and the microstructural investigation was performed using a scanning electron microscope equipped with energy dispersive spectroscopy. The linear thermal expansion coefficient of Zr0.8Nd0.2O1.9 increases upon composite formation with MgO, which is attributed to a higher thermal expansivity of MgO. Similarly, specific heat also increases with the addition of MgO to Zr0.8Nd0.2O1.9. Thermal conductivity was calculated from measured thermal diffusivity, temperature-dependent density and specific heat values. Thermal conductivity of Zr0.8Nd0.2O1.9–MgO (50 wt%) composite is more than that of typical UO2 fuel, supporting the potential of Zr0.8Nd0.2O1.9–MgO composites as target materials for minor actinides transmutation.

Boron-MgO composite as an X-ray transparent pressure medium in the multi-anvil apparatus.

X-ray transparent materials are very beneficial for in situ X-ray experiments in the multi-anvil apparatus. We sintered machinable blocks of boron-MgO composites at 800-1000 °C under atmospheric pressure from a mixture of amorphous boron and brucite or Mg(OH)2. The machinability of composite blocks improved with an increase in the brucite content in the starting material; a brucite content higher than 15 wt. % showed reasonable machinability in forming various shapes such as octahedron, cylinder, and sleeve. We confirmed the feasibility of the boron-MgO pressure medium by successfully generating lower mantle pressure (>23 GPa); its pressure generation efficiency is comparable to that of a Cr2O3 doped MgO pressure medium. The boron-MgO composite is expected to be an excellent thermal insulator owing to the extremely low thermal conductivity of amorphous boron; we confirmed its better thermal insulation performance through a comparative heating test with a zirconia sleeve in a Cr2O3 doped MgO pressure medium. Constituting light elements, the boron-MgO composite has high X-ray transparency, which enables us to conduct various cutting edge X-ray measurements in the large volume multi-anvil apparatus.

Effect of ball-milled MgO and Si3N4 addition on the physical, mechanical and thermal behaviour of aluminium based composite developed by hybrid casting technique

ABSTRACTComposite material via hybrid casting techniques. Ball-milling of Si3N4 and MgO powder was carried out for 100 hours to obtain in single entity particles. MgO powder is used to enhance wettability property of composite with Si3N4 reinforcement in AA2024 aluminium alloy. However, MgO was also responsible to improve tensile strength and hardness of composite material. Microstructure results showed the fair distribution of reinforcement particles developed by the hybrid casting technique. Maximum tensile strength and hardness were found to be 219.55 MPa and 80.86 BHN for ball-milled AA2024/7.5 % Si3N4/5% MgO composite material as heat treated. Minimum thermal expansion was also found for composition AA2024/7.5% Si3N4/5% MgO composite. However, minimum corrosion loss was observed for composition AA2024/10% Si3N4/2.5% MgO composite material. Though, toughness and ductility were reduced by adding the Si3N4 and MgO particles in AA2024 aluminium alloy. XRD result showed the presence of SiO2, Mg, Al, Si3N4, Cu and MgO in ball-milled AA2024/7.5% Si3N4/5% MgO composite material.

Фрактальная размерность поверхности разрушения пористого ZrO2 – MgO композита

Porous ZrO2–MgO composites were studied. The influence of the composition and sintering time on the grain size, porosity, and kinetics of pore size changes was investigated. The fractal dimension and surface roughness of the fracture surface were determined by the method of vertical cross sections by SEM images. The kinetics of change in the average size of micro- and macropores with an increase in sintering time indicates the pursuit of the system to establish a unimodal pore structure owing to volume shrinkage and coalescence of pores. It was shown that changes in the fractal dimension reflect the stages of solid-phase sintering of porous ZrO2–MgO composite and occur only at the second stage of solid-phase sintering. The maximum fractal dimension, equal to 1.5, is reached at the transition from the first to the second stage of solid-phase sintering and is observed when the ratio of large and small pores is 12.5, which indicates the formation of the most developed surface.

Fabrication, Crystalline Behavior, Mechanical Property and In-Vivo Degradation of Poly(l-lactide) (PLLA)-Magnesium Oxide Whiskers (MgO) Nano Composites Prepared by In-Situ Polymerization.

The present work focuses on the preparation of poly(l–lactide)–magnesium oxide whiskers (PLLA–MgO) composites by the in-situ polymerization method for bone repair and implant. PLLA–MgO composites were evaluated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and solid-state 13C and 1H nuclear magnetic resonance spectroscopy (NMR). It was found that the whiskers were uniformly dispersed in the PLLA matrix through the interfacial interaction bonding between PLLA and MgO; thereby, the MgO whisker was found to be well-distributed in the PLLA matrix, and biocomposites with excellent interface bonding were produced. Notably, the MgO whisker has an effect on the crystallization behavior and mechanical properties; moreover, the in vivo degradation of PLLA–MgO composites could also be adjusted by MgO. These results show that the whisker content of 0.5 wt % and 1.0 wt % exhibited a prominent nucleation effect for the PLLA matrix, and specifically 1.0 wt % MgO was found to benefit the enhanced mechanical properties greatly. In addition, the improvement of the degrading process of the composite illustrated that the MgO whisker can effectively regulate the degradation of the PLLA matrix as well as raise its bioactivity. Hence, these results demonstrated the promising application of PLLA–MgO composite to serve as a biomedical material for bone-related repair.