High Shape Recovery Ratio Research Articles

Harnessing nanostructures and fiber architecture: A synergistic leap in shape memory polymer composites

This research investigates the synergistic effects of carbon fiber orientation and nanostructure reinforcement across 21 configurations of shape memory polymer composites. It examines uni-directional (UD), bi-directional Twill (BDT), and bi-directional Plain (BDP) fiber architectures, along with varying concentrations of MWCNT and GnP at 0.4%, 0.6%, and 0.8%. The fabrication process involves initially preparing nanostructure-modified epoxy nanocomposites through ultrasonication followed by hand layup techniques to fabricate three-phase shape memory polymer composites. Optimal tensile performance is observed in GnP-modified UD composites at a 0.6 wt% concentration, achieving a tensile strength of 728.32 MPa and a modulus of 71.29 GPa. Furthermore, enhancements in thermomechanical and shape memory properties are noted in GnP-modified BDT composites and are further improved in GnP-modified BDP composite configurations. GnP-modified composites outperform MWCNT ones due to GnP’s sheet structure aligning parallel to the load and its larger surface area, which facilitate enhanced interaction with the matrix. These improvements, supported by FESEM analysis, highlight enhanced interfacial bonding and result in high shape recovery ratios, with all configurations exceeding 90%, despite polymer modification.

Shape memory cyclic behavior and mechanical durability of woven fabric reinforced shape memory polymer composites

The shape memory cyclic behavior and mechanical durability of the shape memory polymer (SMP) and three woven fabrics (plain, twill, and satin weaves) reinforced shape memory polymer composite (WFR-SMPCs) are characterized to investigate the effect of woven textures on the mechanical and shape memory properties of WFR-SMPCs. Shape memory cycle test, shape memory durability test, and microscopic observation for SMP and WFR-SMPCs were carried out. Experimental results show that the SMP is temperature-sensitive, and higher temperature facilitates the shape memory performance of the material. The woven fabric reinforcements can significantly enhance the mechanical properties of the SMP matrix while still maintaining good shape recovery ratios above 98 % and shape fixation ratios above 90 % even though there is a slight decrease in these values. The twill WFR-SMPC displays the best mechanical performance. The satin WFR-SMPC has the highest shape recovery ratio. The twill WFR-SMPC performs the best in load-bearing capacity and recovery stress. The microscopic observations show that the rotational misalignment and bending of the fiber tows, and damage to the matrix are the main failure modes of the WFR-SMPCs at high shear strain.

4D printing of Nd-Fe-B composites with both shape memory and permanent magnet excitation deformation

Novel composite filaments are developed by mixing PLA, TPU, and Nd-Fe-B components and utilizing melt extrusion for 4D printing. The results reveal that the Nd-Fe-B magnetic particles are uniformly dispersed in the PLA/TPU polymer matrix, and the composite filaments meet the requirements of high-precision printing. Increasing the proportion of Nd-Fe-B magnetic particles in the composite contributes to higher remanence, coercivity, and magnetic energy product for the printed magnets. Under the 70 °C thermal stimulus, it has a high shape fixed ratio (>99 %), a high shape recovery ratio (>90 %), and a rapid response time (≤6.55 s). The magnetic particles accelerate the shape recovery process. Moreover, the petal-like structure and the hollow ball structure are designed and printed. After deformation, each structure can nearly fully recover its initial shape. This recovery is achieved through a non-contact stimulus response based on ’thermal-magnetic’ coupling. The grippers printed by the developed composite show comprehensive properties of shape memory and magnetically controlled smart gripping.

Topological optimisation and laser additive manufacturing of force-direction-sensitive NiTi porous structures with large deformation recovery behaviour

ABSTRACT Optimising the cell type and configuration is a key approach for overcoming stress concentration and irreversible deformation in lightweight lattice structures with high strength. In this work, the topology optimisation method was utilised to design force-direction-sensitive structures, including face-centre loaded (FCL), central-edge loaded (CEL), and hybrid-loaded (HL) structures, which were manufactured by laser powder bed fusion (LPBF) using Nitinol (NiTi) shape memory alloy. Results indicated that the HL lattice exhibited the highest initial peak force of 7.6 kN with higher specific compressive strength (41.74 MPa·cm3/g) and specific energy absorption (6.82 J/g), which was benefit from the layer-by-layer deformation mechanism. Furthermore, the HL lattice also exhibited the best damping properties and energy absorption capacity, while achieving a high shape recovery ratio of 85%. This work offers insights into a design strategy for functional structures with high strength and large deformation recovery capacity.

Influence of Programming and Recovery Parameters on Compressive Behaviors of 4D‐Printed Biocompatible Polyvinyl Chloride or Vinyl–Poly(ε‐Caprolactone) Blends

In this article, a new class of biocompatible shape‐memory polymers (SMPs) through blending pcolyvinyl chloride or vinyl (PVC) and poly(ε‐caprolactone) (PCL) is introduced. The compressive shape‐memory behaviors of 4D‐printed SMP PVC with 5 and 10 wt% of PCL are studied in detail. In this respect, a set of experiments are carried out to understand thermomechanical responses of PVC–PCL blends under various shape‐memory parameters like programming temperature, load‐holding time, applied strain, and recovery temperature. Dynamic mechanical thermal analysis and scanning electron microscope imaging are also performed to provide thermal and morphological analyses. It is found that by raising the recovery temperature from 45 to 65 °C, the shape recovery ratio increases from 5.63 to 7.92 MPa when the PVC–PCL10 is programmed via the hot‐programming (HP) protocol. The highest level of shape fixity (100%) and the best performance of stress relaxation are achieved for HP sample, while the highest shape recovery ratio (100%) is obtained for cold programming. By applying the load‐holding time, the amount of shape fixity can reach from 88.14% to 100%. Results of this research are expected to provide an insightful understanding of the shape‐memory behaviors of PVC–PCL and be instrumental for 4D printing and programming of shape‐adaptive structures like shape‐memory intervertebral cages as spinal support devices.

Multi-stimuli-responsive shape memory flexible composites based on magnetic melamine/polydopamine/phosphorene complex foams and polyethylene glycol

We have developed a novel type of flexible multi-stimuli-responsive shape memory composite system based on a melamine/polydopamine (PDA)/Fe3O4/phosphorene (PR) complex foam and poly(ethylene glycol) (PEG). The system was constructed through coating PDA on the skeleton of the melamine foam and then decorating the PDA layer with Fe3O4 and PR nanosheets, followed by vacuum impregnation of PEG. The resultant composites exhibit an intrinsic thermal-driven shape memory behavior with a high shape recovery ratio of around 100% thanks to their high latent heat capacity derived from the loaded PEG. The introduction of magnetic Fe3O4 nanoparticles and PR nanosheets not only enhances the thermal conductance of the composites but also generates good magnetic and photothermal responsiveness. This enables the composites to obtain good light- and magnetic-driven shape memory capabilities in a shorter shape recovery period. This study offers a new strategy for developing smart materials with multiple and effective response to light, heat, and magnetism.

Multi-responsive shape memory porous composites for self-powered sensors and self-sensing actuators

The integration of materials with multiple functions, like actuating, sensing, and self-powering, is a key focus of soft robotics attributed to their promising applications in various fields. However, integrating these functions in a single material still remains a significant challenge. Herein, we proposed a polyvinyl alcohol/ multiwalled carbon nanotube porous composite with multi-responsive shape memory actuating and self-powered sensing functions. For actuators, the porous composites exhibited excellent thermo, near-infrared light, and water-induced shape memory performance with high shape fixation and shape recovery ratio over 94 %. For sensors, the fabricated porous materials-based triboelectric nanogenerator (PTENGs) exhibited high output performance with power density of 4.57 W m−2, enabling their use as pressure and humidity sensors. Moreover, it was found that the output performance of PTENG can be adjusted utilizing the shape memory effect of porous composites, while the self-monitoring function of shape memory actuators was achieved through the self-powered sensing of PTENG. This work presents a new strategy for developing an integrated material with multi-responsive actuating and self-powered sensing functions.

Wood as a hydrothermally stimulated shape-memory material: mechanisms of shape-memory effect and molecular assembly structure networks

Abstract This study aimed to evaluate the shape-memory effect (SME) of wood (Populus x beijingensis W. Y. Hsu) and identify the net-points and switches in its molecular and morphological structures. During several cycles of deformation and subsequent recovery, a high shape recovery rate and ratio were maintained. The transverse compression tests of wet and dry wood reveal that the hydrothermal coupling stimulation can considerably reduce the strength of wood. The X-ray diffraction characterization of wood under hydrothermal stimulation shows that the role of network nodes in the SME of wood is influenced by temperature. The wavenumber shifting and changes in the intensity ratio of the characteristic Fourier transform infrared peaks showed that hydrogen bonds acted as switches for the water-stimulated shape-memory behavior. By taking into account viscoelastic relaxation, a kinetic model derived from nonequilibrium thermodynamic fluctuation theory was used to describe the shape recovery process. The effects of hydration on recovery kinetics, activation, and dynamic mechanical behaviors were also studied. To explain the shape-memory mechanism of wood under hydrothermal stimulation, a hybrid-structure network model based on a single three-dimensional switch network was proposed in this study.

Development of cyanate ester‐based shape memory composite reinforced by multi‐walled carbon nanotube modified with silicon dioxide

AbstractCyanate ester‐based shape memory composites with superior mechanical properties and good shape memory performance are needed in the aerospace field. In this work, we utilized a simple sol–gel method to fabricate multi‐walled carbon nanotubes coated with silica (MWCNT@SiO2), which were used to construct a cyanate ester‐based shape memory composite (SMPC). The moisture resistance of SMPC was improved by the introduction of MWCNT@SiO2. MWCNT@SiO2 had an efficient enhancement effect on the mechanical strength and toughness of SMPC, and the SMPC exhibited the best mechanical properties with 0.9 wt% loading of MWCNT@SiO2, which was associated with the dispersion of MWCNT@SiO2 in the resin matrix. Compared to neat cyanate ester and epoxidized hydroxyl‐terminated polybutadiene resin matrix, it was found that the storage modulus of SMPC increased and the values of glass transition temperatures decreased by incorporation of MWCNT@SiO2. Meanwhile, the SMPC retained good shape memory performance, corresponding to high shape fixity ratio and shape recovery ratio (over 98% after 10 test cycles). The addition of MWCNT@SiO2 accelerated the shape memory progress of SMPC.

Magnetic- and light-responsive shape memory polymer nanocomposites from bio-based benzoxazine resin and iron oxide nanoparticles

Shape memory polymers (SMPs) are a class of smart materials that can be programmed to recover from temporary shape to permanent shape by applying external stimuli (temperature, magnetic field, light, electric field, and moisture, etc.). This unique property of SMPs makes them an appealing candidate in application for soft robotics, such as smart actuators, artificial muscles, and biomedical devices. In this contribution, we have developed multi-stimuli-responsive SMPs from bio-based benzoxazine resin and iron oxide nanoparticles (Fe3O4 NPs) that could be actuated by magnetic field and light. The nanocomposites were characterized by infrared spectroscopy, in which molecular interaction between benzoxazine/epoxy copolymers and Fe3O4 NPs was observed. Effects of nanoparticle content (0–5 wt%) on magnetic, mechanical, thermal, and thermo-mechanical properties of nanocomposites were investigated. Shape memory performance of nanocomposites was significantly improved with incorporation of Fe3O4 NPs. Shape fixity increased from 85% of neat copolymers to 93% of copolymers filled with 3 wt% Fe3O4 NPs, while shape recovery increased from 94% to 98%. Moreover, shape fixity could be done without external force contact by 808 nm-light actuation and magnetic attraction, due to photothermal and magnetic properties of nanocomposites. Shape recovery was tested under actuation by magnetic field. The highest shape recovery ratio was 99% within 26 s for copolymers filled with 5 wt% Fe3O4 NPs. Lastly, preliminary application of nanocomposites was demonstrated as they could push a 1 g-object within 10 s of actuation by magnetic field. In overall, these nanocomposites with multi-stimuli-responsive shape memory property had a good potential to be applied for soft robotics.

4D Printing of Single-Network Shape Memory Polyurethanes with Two-Way Actuation Properties

Two-way shape memory polymers (SMPs) have received much attention due to their ability to enable stimuli-responsive reversible structures without requiring repeated human intervention, which may be useful for application in many fields where multiple actuation cycles are desired. However, many layered or composite SMP systems are not integrated structures and suffer from several disadvantages, such as poor interlayer adhesion with limited actuation repeatability. In addition, two-way SMPs are limited by their manufacturing method to producing user-defined, complex, high-precision devices and parts. In this work, we developed a 3D-printable resin comprising two polyurethane-based oligomers with distinctly different transition temperatures─polypentadecalactone diacrylate (PPDLDA) and polycaprolactone diacrylate (PCLDA)─together with other monomers to fabricate single-network two-way shape memory smart materials by digital light projection 3D printing. The chemical, mechanical, and thermal properties of printed products can be easily tuned by facile manipulation of monomer and oligomer compositions. The PCLDA and PPDLDA switching segments were found to exhibit high mean shape fixity ratios (Rf) of >97% and high shape recovery ratios (Rr) of >89%. The strategy for achieving 3D-printable single-network two-way SMPs presented herein holds promise for applications in soft robotics, medicine, and so forth.

Shape reconfiguration and functional self-healing of thermadapt shape memory epoxy vitrimers by exchange reaction of disulfide bonds

Epoxy-based shape memory materials still face many challenges from preparation to application. Designing dynamic covalent bonds into the cross-linked network of epoxy can bring many new properties to them, which is expected to solve some of the problems faced. In this paper, epoxy vitrimers with different contents of exchangeable disulfide bonds were synthesized by the polymerization of hydrogenated epoxy resins with diacids containing dynamic disulfide bonds. The effect of disulfide bond content on the properties of epoxy vitrimers was systematically studied. By activating the exchange reaction of disulfide bonds, the permanent shape of epoxy vitrimers can be reconfigured, even from two to three dimensions. The time required for reconfiguring is affected by the content of disulfide bonds, the more disulfide bonds, the shorter the time required. The epoxy vitrimers with more content of disulfide bonds were found to have lower recovery ratio loss after the same shape memory cycle by thermal bending experiments. More importantly, the epoxy vitrimers with more content of disulfide bonds also exhibited better functional self-healing properties. The decreased recovery ratio can be healed by periodic heat treatment, thus ensuring that the epoxy vitrimers perform more shape memory cycles and maintain a high shape recovery ratio. These experimental results will serve as a basis for expanding the range of applications and prolonging the service life of epoxy-based shape memory materials.

Synthesis of dual‐stimuli‐responsive polyurethane shape memory nanocomposites incorporating isocyanate‐functionalized Fe3O4 nanoparticles

AbstractThermally and magnetically stimulated shape memory polyurethane (PU) nanocomposites were synthesized for intravascular stent applications. For this end, Fe3O4 magnetic nanoparticles (MNPs) were modified with octadecyl isocyanate (OD) to increase their affinity with the PU matrix by formation of the covalent urea linkages. The results showed that the OD‐grafted MNPs were replaced instead of carbonyl groups of polycaprolactone (PCL) soft segments in hydrogen bond formation with the urethane linkages. This led to higher phase separation degrees among the soft and hard phases, thereby PCL chains could reveal higher crystallization potential. Mechanical studies showed that the nanocomposites had high mechanical strength, Young's modulus, and elongation at break, which improve their practical applications. The nanocomposites showed thermo‐responsive shape memory behavior with a high shape recovery and shape fixity ratios due to the presence of the crystallizable PCL segments. The nanocomposite containing 10 wt% of the OD‐grafted MNPs could recover its original shape (during 90s) in a relatively weak alternating magnetic field (350 kHz and 12.9 kA/m). These results indicated that the prepared nanocomposites could be used to normalize the narrowed blood vessels through the remotely and magnetically‐controllable restricted shape recovery process.

Effect of volume fraction and unit cell size on manufacturability and compressive behaviors of Ni-Ti triply periodic minimal surface lattices

Ni-Ti shape memory alloys with triply periodic minimal surface (TPMS) lattice structures have aroused increasing interests due to their great application potential in bone tissue engineering. In this study, the effect of volume fraction and unit cell size on the manufacturability, compressive mechanical properties, and shape memory behaviors after compression of Ni-Ti Gyroid TPMS lattice structures, which were fabricated by laser powder bed fusion ( L -PBF), were systematically investigated. A mathematical model was established to analyze the geometric influence factors on manufacturing fidelity of Ni-Ti Gyroid TPMS lattice structures fabricated by L -PBF. It was revealed that the manufacturing fidelity decreased as the volume fraction and unit cell size decreased due to the aggravation of powder adhesion caused by the increase of specific surface area and overhanging rate of struts. Three power-law equations based on the Gibson-Ashby models were established to describe the dependences of compressive modulus, nominal yield strength, and ultimate strength of Ni-Ti Gyroid TPMS lattice structures fabricated by L -PBF on the volume fraction and unit cell size. All the above mechanical properties showed positive dependences on the volume fraction but negative dependences on the unit cell size. Both the volume fraction and unit cell size had little influence on the martensitic transformation temperatures as well as the total shape recovery ratio of Ni-Ti Gyroid TPMS lattice structures prepared by L -PBF. All the as-built Ni-Ti lattices exhibited high total shape recovery ratios of above 96.5% after 8% compressive deformation at room temperature (RT). But noteworthily, as the volume fraction increased, the pseudoelastic response (i.e., the recovered strain during unloading) rapidly decreased, followingly the recovered strain during heating increased. This was ascribed to the enhanced stability of stress-induced martensite at RT caused by the increased actual strain of local struts at the same overall compressive deformation in the Ni-Ti lattices with higher volume fractions. In contrast, the Ni-Ti lattices with different unit cell sizes exhibited similar strain distribution and consequently similar deformation recovery behaviors. • Manufacturing fidelity decreases as volume fraction and unit cell size decrease. • Mechanical properties show positive dependences on volume fraction. • Mechanical properties exhibit negative dependences on unit cell size. • Both volume fraction and unit cell size hardly affect the total recovered strain. • Superelastic response decreases as volume fraction increases.

A novel multi‐functional model thermoset and PDA‐coated PU nanocomposite based on graphene and an amphiphilic block copolymer

AbstractThe need for multi‐functional biomaterials has driven researchers towards more complex multi‐component structures with tailor‐made surface modifications. In this research, thermoset polyurethanes (tPUs) of PCLy‐PEGx‐PCLy, with variable block lengths, and graphene were developed and further surface‐modified by Polydopamine (PDA) to improve cell adhesion. The viscoelastic and thermal properties of the tPUs were studied by DMA and DSC. The results proved the increased crystallization of the soft segments as the length of PCLy and PEGx blocks increased. The stress–strain results indicate the tPU nanocomposites possess high‐elastic modulus (38.46–96.17 MPa), and lower elongation (132.6%–375.9%) compared to thermoplastic PU nanocomposites. The tPU specimens proved to have very high shape recovery ratios (88.07%–94.93%). PDA surface deposition led to an increase in surface roughness and a change in surface topography. The PDA‐modified specimens showed significant improvement in protein adsorption and cell proliferation and also increased the hydrolytic degradation extent of the tPUs, proving the multi‐functional role of the biomaterials.

Smart Shape-Memory Polymeric String for the Contraction of Blood Vessels in Fetal Surgery of Sacrococcygeal Teratoma.

Shape-memory polymers (SMPs) are promising materials in numerous emerging biomedical applications owing to their unique shape-memory characteristics. However, simultaneous realization of high strength, toughness, stretchability while maintaining high shape fixity (Rf ) and shape recovery ratio (Rr ) remains a challenge that hinders their practical applications. Herein, a novel shape-memory polymeric string (SMP string) that is ultra-stretchable (up to 1570%), strong (up to 345MPa), tough (up to 237.9MJm-3 ), and highly recoverable (Rf averagely above 99.5%, Rr averagely above 99.1%) through a facile approach fabricated solely by tetra-branched poly(ε-caprolactone) (PCL) is reported. Notably, the shape-memory contraction force (up to 7.97N) of this SMP string is customizable with the manipulation of their energy storage capacity by adjusting the string thickness and stretchability. In addition, this SMP string displays a controllable shape-memory response time and demonstrates excellent shape-memory-induced contraction effect against both rigid silicone tubes and porcine carotids. This novel SMP string is envisioned to be applied in the contraction of blood vessels and resolves the difficulties in the restriction of blood flow in minimally invasive surgeries such as fetoscopic surgery of sacrococcygeal teratoma (SCT).

Multifunctional Phase Change Composites Based on Elastic MXene/Silver Nanowire Sponges for Excellent Thermal/Solar/Electric Energy Storage, Shape Memory, and Adjustable Electromagnetic Interference Shielding Functions.

Multifunctional phase change materials (PCMs) are highly desirable for the thermal management of miniaturized and integrated electronic devices. However, the development of flexible PCMs possessing heat energy storage, shape memory, and adjustable electromagnetic interference (EMI) shielding properties under complex conditions remains a challenge. Herein, the multifunctional PCM composites were prepared by encapsulating poly(ethylene glycol) (PEG) into porous MXene/silver nanowire (AgNW) hybrid sponges by vacuum impregnation. Melamine foams (MFs) were chosen as a template to coat with MXene/AgNW (MA) to construct a continuous electrical/thermal conductive network. The MF@MA/PEG composites showed a high latent heat (141.3 J/g), high dimension retention ratio (96.8%), good electrical conductivity (75.3 S/m), and largely enhanced thermal conductivity (2.6 times of MF/PEG). Moreover, by triggering the phase change of the PEG, the sponges displayed a significant photoinduced shape memory function with a high shape fixation ratio (∼100%) and recovery ratio (∼100%). Interestingly, the EMI shielding effectiveness (SE) can be adjusted from 12.4 to 30.5 dB by a facile compression-recovery process based on shape memory properties. Furthermore, a finite element simulation was conducted to emphasize the advantage of the MF@MA/PEG composites in the thermal management of chips. Such flexible PCM composites with high latent heat storage, light-actuated shape memory, and adjustable EMI shielding functions exhibit great potential as smart thermal management materials in military and aerospace applications.

Development of multi-angle fiber array for accurate measurement of flexion and rotation in human joints

Herein, we have proposed a method that uses a highly stretchable and conductive fiber-based multi-angle fiber array, which precisely measures human joint motion in various degrees of freedom (flexion and rotation) at the shoulders, knees, and wrists in real time. By embedding conductive carbon nanotubes (CNTs) within spandex fibers of high elasticity and shape recovery ratio, we monitored joint motion stably without degrading the fiber’s conductivity even during repeated stretching and contraction of different lengths. The strain occurring in a specific direction was monitored using mapping images generated due to the change in resistance that occurred when 12 CNT-embedded spandex fibers arranged in radial lines at intervals of 15° were stretched or contracted by an external force. The proposed high-precision joint-monitoring technology measures human motion accurately and is applicable for use in wearable healthcare devices that require precise measurements.

4D printing high temperature shape-memory poly(ether–ether–ketone)

Shape-memory polymers have exhibited extensive attractive properties for practical utility and applied potential, such as in clothing industry and for medical implants, which demands soft materials amenable to change shapes at low temperature. Whereas, potential applications in aerospace engineering require materials with higher modulus and higher transition temperature to ensure their effectiveness under harsh environments. As an engineering thermoplastic polymer material, poly(ether–ether–ketone) (PEEK) is a promising candidate that meets the stringent requirements for aerospace applications. Yet, additive manufacturing of PEEK polymers, to bring out the full potential of the materials, remains challenging and unfulfilled because of the intrinsic very high processing temperature and high modulus. In this paper, we present that 4D printing of the high temperature PEEK polymer with outstanding shape memory properties. We systematically investigate the effect of different printing parameters and heat treatment conditions on the corresponding shape memory performance, which has been rarely reported. The highest shape fixity ratio and highest shape recovery ratio that we can achieve in the 3D-printed PEEK samples is 99% and 87.8%, respectively, with Young’s modulus of 3.23 GPa and good thermal stability below 520 °C. Furthermore, the incomplete shape recovery processes have been exploited to fabricate more complex programming of shape changes and to demonstrate the potential for practical applications, and models of PEEK have been designed and printed to demonstrate the outstanding shape memory properties and for potential applications in high temperature environment.

Controlling the switching temperature of biodegradable shape memory polymers composed of stereocomplex polylactide / poly(d,l-lactide-co-ε-caprolactone) blends

We synthesized new biodegradable shape-memory polymers (SMPs) by blending synthesized poly(d,l-lactide-co-ε-caprolactone) (PLCL) and stereocomplex polylactide (sc-PLA) to be used as biomaterials for medical devices. PLCL copolymers (Mn ∼80,000) with various monomer ratios (LA:CL) were synthesized by the bulk ring-opening polymerization. The glass transition temperature of the resulting PLCL copolymers could be well controlled from −3 °C to 60 °C, agreeing well with the values by the Gordon-Taylor equation, confirming the homogeneous random distribution of LA and CL monomers in the synthesized PLCL. The synthesized PLCL and sc-PLA were eventually blended for the fabrication of biodegradable SMPS. The PLCL/sc-PLA blend samples possessed the sc-PLA crystallinity of ∼13%, which effectively worked as crosslinkings, exhibiting shape-memory behavior with various switching temperatures (30.5°C–62 °C) and shape-recovery ratios realized by adjusting the CL ratio of the PLCL copolymers: a lower CL ratio resulted in a higher switching temperature and a higher shape-recovery ratio.