Blend System Research Articles

Polyurethane-based composite binder for poroelastic road surface: composition, preparation and properties

To address the high cost and poor water stability of polyurethane (PU) binder used in poroelastic road surface (PERS), a type of PU-based composite binder prepared at room temperature was proposed by using PU as the main ingredient, emulsified asphalt (EA), cement, and defoamer as auxiliary agents. The stabilities of different types of polyurethane-emulsified asphalt (PU-EA) blend systems were investigated and the mix composition of the PU-EA blend system was determined through molecular dynamics (MD) simulations. The interaction mechanisms of all components of the PU-based composite binder were revealed by microscopic measurements through Fourier transform infrared (FTIR) spectroscopy and fluorescence microscopy (FM). The strength and water stability of the PERS mixture bound by the PU-based composite binder were evaluated by the indirect tension (IDT) test and the Cantabro abrasion test. The results showed that the stability of the polyether polyurethane (PEUR)-cationic emulsified asphalt (CEA) blend system was the best, and the potential energy of the PU-EA blend system was the lowest when the PU content was around 50 wt%. Both physical and chemical reactions occurred simultaneously in the polyurethane-emulsified asphalt-cement (PU-EA-C) blend system's components. The calcium silicate hydrate (C-S-H) enhanced the crosslinking gel properties of the PU-EA-C blend system. Cement improved the performance of the PERS mixture in a more efficient way than the PU. When the PU-based composite binder composed of 50 wt% PU, 41 wt% EA, 9 wt% cement, and 0.5 wt% defoamer was used, the water stability and strength performance of PERS mixture were the best. The material cost of the suggested PU-based composite binder was nearly half that of commonly used PU, while the material cost of the PERS mixture was reduced by 25%. These findings would serve as useful references for the promotion and application of PERS pavement.

Structure and properties of bio‐based poly(trimethylene terephthalate)/polyamide 56 blends prepared by melt mixing

AbstractThe extensive use of conventional petroleum‐based polymers consumes large amounts of energy and emits a lot of carbon dioxide. Therefore, the development and popularization of bio‐based polymer materials are highly significant for ecological reasons. Herein, a series of poly(trimethylene terephthalate)/polyamide 56 (PTT/PA56) blends with different weight ratios were prepared by melt blending of two bio‐based polymers, PTT and PA56. The phase structure, miscibility, crystallization and melting behaviors, crystal structure, and mechanical and water absorption properties of PTT/PA56 blend systems were investigated. The results showed that PTT and PA56 were immiscible in the whole range of compositions. The immiscibility of the blend system intensified with the increase of dispersed phase content. As PA56 content increased, tensile strength and elongation at break of samples assumed an increasing trend, whereas impact strength initially remained almost unchanged and then gradually decreased. In contrast, increasing PA56 content gradually increased water absorption of samples. Comprehensive analysis indicated that the best combination of different properties was obtained for the PTT/PA56 blends including 60–80 wt% PA56.

On the Mechanical, Thermal, and Rheological Properties of Polyethylene/Ultra-High Molecular Weight Polypropylene Blends.

The novel ultra-high molecular weight polypropylene (UHMWPP) as a dispersed component was melt blended with conventional high-density polyethylene (PE) and maleic anhydride grafted-polyethylene (mPE) in different proportions through a kneader. Ultra-high molecular weight polypropylene is a high-performance polymer material that has excellent mechanical properties and toughness compared to other polymers. Mechanical, thermal, and rheological properties were presented for various UHMWPP loadings, and correlations between mechanical and rheological properties were examined. Optimal comprehensive mechanical properties are achieved when the UHMWPP content reaches approximately 50 wt%, although the elongation properties do not match those of pure PE or mPE. However, it is worth noting that the elongation properties of these blends did not match those of PE or mPE. Particularly, for the PE/UHMWPP blends, a significant drop in tensile strength was observed as the UHMWPP content decreased (from 30.24 MPa for P50U50 to 13.12 MPa for P90U10). In contrast, the mPE/UHMWPP blends demonstrated only minimal changes in tensile strength (ranging from 29 MPa for mP50U50 to 24.64 MPa for mP90U10) as UHMWPP content varied. The storage modulus of the PE/UHMWPP blends increased drastically with the UHMWPP content due to the UHMWPP chain entanglements and rigidity. Additionally, we noted a substantial reduction in the melt index of the blend system when the UHMWPP content exceeded 10% by weight.

Molecular simulation on compatibility and mechanisms of SBS and PTW polymer modifiers in asphalt binder.

Ultrathin overlays are preventive maintenance measures; the tensile and shear stresses generated inside a structural layer under vehicle load are greater than those of conventional thickness asphalt pavement. Therefore, asphalt binders must use high-viscosity and elasticity unique cementing materials to ensure stability. To investigate the modification mechanism of styrene-butadiene-styrene (SBS)/ethylene-butyl acrylate-glycidyl methacrylate copolymer (PTW) high-viscosity modified asphalt binder suitable for ultrathin overlays, the compatibility and molecular behavior of SBS/PTW high-viscosity modified asphalt binder were analyzed by the molecular dynamics (MD) method. These research results provide a reference for preparing ultrathin overlay high-performance composite modified asphalt binder. SBS molecular models, PTW molecular models, asphalt binder molecular models, SBS/asphalt binder blend systems, and SBS/PTW/asphalt binder blend systems were sequentially constructed using Materials Studio (MS) software. The compatibility of SBS, PTW, and SBS/PTW with asphalt binder and the diffusion coefficients of SBS, PTW, and SBS/PTW in the asphalt binder were investigated separately using the MD method. The mechanical properties and molecular behavior of SBS, PTW, and SBS/PTW blended with asphalt binder were studied. The research results indicate that the compatibility of PTW with asphalt binder is better than that of SBS with asphalt binder. PTW can effectively decrease the solubility parameter of asphalt binder and improve the compatibility between SBS and asphalt binder. PTW effectively improves the diffusion coefficient and interaction energy of SBS in asphalt binder by up to 29% and 83%. In addition, SBS/PTW had a significant positive effect on the mechanical properties of the asphalt binders, increasing the elastic modulus (E), bulk modulus (K), and shear modulus (G) of the asphalt binder by 4.6%, 9.5%, and 3.5%, respectively, compared to SBS. The results indicate that the SBS/PTW modified asphalt binder composite can significantly improve the high-temperature shear resistance of asphalt binder. Meanwhile, SBS and PTW improve the self-aggregation behavior between asphalt binder component molecules. The distance between the center of mass of asphalt binder and resin system molecules is increased. PTW enhances the extensibility of the branched chains of asphalt binder component molecules and improves the interaction between asphalt binder components and the chains. This further enhances the density and stability of the asphalt binder molecular structure system, improving the physical properties of the asphalt binder.

Preparation and Characterization of Polycarbonate-Based Blend System with Favorable Mechanical Properties and 3D Printing Performance.

Recently, material extrusion (MEX) 3D printing technology has attracted extensive attention. However, some high-performance thermoplastic polymer resins, such as polycarbonate (PC), cannot be processed by conventional MEX printing equipment due to poor processing performance. In order to develop new PC-based printing materials suitable for MEX, PC/poly(butylene adipate-co-terephthalate) (PBAT) blends were prepared using a simple polymer blending technique. It was found that the addition of PBAT component significantly improved processing performance of the PC, making the blends processable at 250 °C. More importantly, the PC was completely compatible with the PBAT, and the PBAT effectively reduced the Tg of the blends, endowing the blends with essential 3D printing performance. Furthermore, methyl methacrylate-butadiene-styrene terpolymer (MBS) was introduced into the PC/PBAT blends to improve toughness. SEM observations demonstrated that MBS particles, as stress concentration points, triggered shear yielding of polymer matrix and absorbed impact energy substantially. In addition, the MBS had little effect on the 3D printing performance of the blends. Thus, a PC/PBAT/MBS blend system with favorable comprehensive mechanical properties and 3D printing performance was achieved. This work can provide guidance for the development of novel MEX printing materials and is of great significance for expanding the variety of MEX printing materials.

Improvement of properties of polylactic acid/polypropylene carbonate blends using epoxy soybean oil as an efficient compatibilizer

Epoxidized soybean oil (ESO) was used as a compatibilizer and blended with polylactic acid (PLA) and polypropylene carbonate (PPC) resin to prepare a series of PLA/PPC/ESO blends with varying compositions. The influence of the variation in the amount of ESO added to the blend system on the thermal properties, optical properties, rheological properties, mechanical properties, and microscopic morphology of the blends was studied. The research indicates that ESO can react with PLA and PPC to form a chemical bond interface, which improves the compatibility of PLA and PPC to a certain extent. With the increase in the amount of ESO added to the blend (1– 5 phr), the complete decomposition temperature, storage modulus, loss modulus, complex viscosity, notched impact strength, and elongation at break of the blend all show a trend of continuous increase. At the same time, the melt flow rate, light transmittance, and tensile strength of the blend do not show significant fluctuations. When the amount of ESO in the system is 5 phr, compared with the PLA/PPC blend, the notched impact strength and elongation at break of the PLA/PPC/ESO blend increase from 4270.3 J/m2, 43.89 % to 8560.4 J/m2, 211.28 %, respectively, and its tensile strength and transmittance still remain around 63 MPa, 92 %. This improves the toughness of the blend while maintaining its rigidity, demonstrating excellent mechanical and optical properties. At this time, the microscopic morphology of the fracture surface of the impact sample also shows obvious characteristics of tough fracture. However, when the amount of ESO added to the blend is excessive (6 phr), the compatibility of the blending system decreases, which will degrade the performance of the blending material and ultimately destroy the phase morphology of the blend and reduce its mechanical properties.

Copyrolysis characteristics of polyvinyl chloride, polyethylene and polypropylene based on ReaxFF molecular simulation

Reactive force field molecular dynamics (ReaxFF MD) simulation was used to study the copyrolysis behaviour of waste plastics i.e., polyvinyl chloride (PVC), polyethylene (PE), and polypropylene (PP) from three perspectives: (1) gas phase products, (2) reaction route, and (3) activation energy. The results demonstrate that the thermogravimetric (TG) experiment's findings and the weight loss characteristics of PVC/PE/PP copyrolysis obtained by ReaxFF MD simulation were consistent. Copyrolysis changed the amount of gas phase products generated, the direction of free radical movement, and the range of temperatures at which they were produced in considerable quantities. Due to the transfer of chloride (Cl) radicals, both PE and PP had a detrimental synergistic impact on the production of hydrogen chloride (HCl). Based on the first-order reaction kinetics model, the copyrolysis of waste plastics significantly lowered the total activation energy of the mixture, and the activation energy of PVC/PE/PP ternary blend system decreased most significantly.

Preparation and Characterization of Polydopamine-Modified Halloysite Nanotubes and Their Effect on a Natural Rubber, Chloroprene Rubber and Chloro-Isobutylene-Isoprene Rubber Blend

The superior physical and mechanical performances of halloysite nanotubes (HNTs) make them ideal fillers for rubber reinforcement. However, due to the abundant hydroxyl groups on their surface, they are highly polar and have poor compatibility with polymers, making it difficult for them to disperse uniformly in polymers, thus limiting their application in rubber composites to a certain extent. In this paper, noncovalently modified HNTs filled with a natural rubber/chloroprene rubber/chloro-isobutylene-isoprene rubber (NR/CR/CIIR) blend system, using polydopamine(PDA) as a surface modifier, was investigated. and a green and high-performance PDA/HNTs/NR/CR/CIIR composite was prepared by mechanical blending. Transmission electron microscopy (TEM) showed that the original HNTs had a hollow, multi-walled nanotube structure, and the outer surface of the PDA-modified halloysite nanotubes(PDA/HNTs)showed an obvious cladding layer. X-ray diffraction indicated that the modification experiments did not damage the halloysite crystal structure; the modifier only interacted on the outer surface of the HNTs. Zeta potential and thermogravimetric analysis (TGA) further indicated the presence of interfacial interactions between PDA and HNTs, suggesting that PDA was successfully grafted to the surface of HNTs. In addition, the effects of PDA/HNTs on the mechanical properties, vulcanization properties and Rubber Process Analyzer (RPA analysis) of the NR/CR/CIIR blend were also investigated. The dispersion of HNTs in the NR/CR/CIIR blend was enhanced by the adsorption of PDA on the HNTs surface by non-covalent bonds, and the comprehensive properties of the composites were improved.

High efficiency ternary organic solar cells based on two nonfused ring electron acceptors with similar molecular structure

Organic solar cells (OSCs) based on nonfused ring electron acceptors (NFREAs) have shown great potential for future commercial applications due to their reduced synthesis complexity and low cost, and ternary strategy is a promising path for further boosting the development of NFREAs-based OSCs. Herein, two NFREAs FO-4Cl and FO-N with similar molecular structure are employed to fabricate high-performance ternary OSCs via combining a commonly used polymer donor PBDB-T. The PBDB-T:FO-4Cl and PBDB-T:FO-N binary devices can exhibit PCEs of 12.05% and 11.33%, respectively. Incorporating FO-N into the binary blend PBDB-T:FO-4Cl, the PBDB-T:FO-4Cl:FO-N ternary device can achieve a significantly improved PCE of 13.15% with a Voc of 0.87 V, a Jsc of 20.59 mA/cm2 and an FF of 73.02%, which is 9% and 16% higher than the PBDB-T:FO-4Cl and PBDB-T:FO-N based binary devices, respectively. The enhanced Jsc and FF can be ascribed to the enhanced photon harvesting, improved film morphology and high and balanced charge transport. Meanwhile, the Voc of ternary devices are gradually improved after the introduction of the high-lying LUMO component FO-N, which demonstrates that the two acceptors may form alloy state in the blend system. Our results demonstrate that ternary strategy is an effective path for further boosting the performance of NFREA-based OSCs by incorporating isogenous acceptors.

Efficient capture of benzene and its homologues volatile organic compounds with protic [MIM][NTF2] and aprotic [EMIM][NTF2] ionic liquids: Experimental and computational thermodynamics

Using new green solvents to effectively capture volatile organic compounds (VOCs) is considered as an attractive green sustainable chemical development route. In this work, benzene, toluene, ethylbenzene and p-xylene (BTEX) were selected as typical aromatic VOCs. The gas absorption performance of proton [MIM][NTF2] and aprotic [EMIM][NTF2] ionic liquids (ILs) for BTEX were studied by computational thermodynamics combined with gas absorption experiments. Absorption experiments of BTEX and regeneration experiments of ILs were carried out at different temperatures, and ILs had good stability. The interaction type and intensity were determined by Interaction Region Indicator (IRI) analysis of IL-BTEX blend systems. The C-H···π and π-π interaction between imidazole ring and BTEX were the direct reason why ILs can efficiently absorb BTEX. Molecular dynamics simulations were performed to explore the diffusion behavior of gas in ILs. The increase of methyl group increases the interaction strength of the system, and the fractional free volume of IL-BTEX blend systems decreases gradually, which limits the diffusion of BTEX. Non-bond interaction analysis shows that van der Waals interaction was the main driving force of BTEX absorption in ILs.

Hydrophilic-to-hydrophobic conversion of polyamide 6-based mat via polyvinylidene fluoride nanofiber integration with enhanced oil-water separation

This study presents a unique technique for fabricating a highly effective hydrophobic polyamide 6 (PA6)-based nonwoven mat with remarkable performance in hydrophobicity and oil-water separation. Utilizing a ternary blend system of polypropylene (PP)/PA6/polyvinylidene fluoride (PVDF) based on Harkin's theory and employing an in-situ fibrillation process, a distinctive micro-nano hierarchical structure is achieved. The removal of the PP matrix results in a nonwoven mat composed of bimodal PA6 microfibers surrounded by PVDF nanofibers. Water contact angle measurements revealed micro-nano hierarchical structure in the mat-induced hydrophobicity on the intrinsically hydrophilic PA6. Further optimization of the PP removal process enhances the hydrophobicity of the micro-nano fibrillar structure. The mat also demonstrates outstanding efficiency in separating oil and water, with an impressive oil-water separation efficiency of up to 97.4%. This scalable fabrication technique opens significant opportunities for the utilization of hydrophobic PA6 nonwoven mats in diverse industries, including textiles and other sectors where water repellency is crucial. Furthermore, these hydrophobic PA6 nonwoven mats hold great potential for sustainable applications in environmental settings, addressing the growing need for both hydrophobicity and efficient oil-water separation solutions.

Cure characteristics, compression set, swelling behaviors, abrasion resistance and mechanical properties of nanoclay (Cloisite 15A, Cloisite 20A and Cloisite 30B) filler filled EPDM/NBR blend system

Cure characteristics, compression set, swelling behaviors, abrasion resistance and mechanical properties of nanoclay (Cloisite 15A, Cloisite 20A and Cloisite 30B) filler filled EPDM/NBR blend system

Cryogenic treatment: Processing segment to tailor the interface and improve mechanical performance of impact modified PET/PBT blends

Cryogenic treatment of polymers is a well-known area of research these days. Many reports confirm the fact that, similar to metals, polymeric materials also undergo some structural changes that ultimately enhance mechanical properties like wear performance, tensile strength, impact strength, elongation, hardness, etc. The cryogenic treatment has proven an advantage for improving the properties of both virgin polymers and polymer micro- and nanocomposites. The present study, the first of its kind, reports the effect of cryogenic treatment on polymeric blends. An attempt is made to explore the effect of the treatment parameters, like temperature and time, on the impact modified and unmodified PET/PBT blends. Similar to the polymers and composites, the blend systems studied here reflect significant improvement by ∼50% in wear performance, ∼16–19% in tensile strength, and ∼9% in impact strength after cryogenic treatment. Thus, after extensive analysis of the material properties, structure, and thermal behavior, cryogenic treatment of PET/PBT blends, both impact-modified and unmodified, is advocated as an effective tool for tailoring the interface and improving performance.

Studies on the Effect of the Addition of Nano-Spherical Particles of Aluminum on the Thermal, Mechanical, and Morphological Properties of PBT-PET Blend Composites.

In previous works, we had found that the addition of micron-sized, irregular-shaped aluminum (Al) powder, or Al nano platelets (flakes), improved the mechanical properties of polyesters, and that, additionally, the flakes led to an increase in electrical conductivity. The aim of this work was to examine the effect of nano-spherical particles of aluminum in a 60/40 PBT/PET polyester blend. A blend was used because it can help with the formation of a segregated network of metal particles that allows electrical conductivity at low loading. The notched Izod impact of Al nano-spherical composites increased with nano Al content up to an addition level of 2 vol.%. However, the tensile strength and flexural strength decreased gradually with increasing filler loading. Thus, the spherical shape and nano size of the Al particle caused it to be less effective than the micron-sized, irregular-shaped Al powder, or the Al flakes. The reason for this is that, while nano spherical particles have high surface area for bonding with the matrix, the Al-Al aggregation stands in the way of wetting by the polymer melt, whereas aggregation in flakes does not cause as much of a problem. The segregated network structure to enhance electrical conductivity did not form in this blend system with nano spherical particles. The nano-spherical Al acted as a nucleating agent but did not cause transesterification between the two polyesters or make it more susceptible to degradation.

(Invited) Ternary-Cascaded Triplet Energy Landscape for Solid-State Photon Upconversion

Here, we introduce a new strategy for improving the efficiency of solid-state photon upconversion based on triplet–triplet exciton annihilation (TTA-UC). We designed a ternary blend system consisting of a triplet sensitizer (TS), an exciton-transporting host polymer, and a small amount of an annihilator. The key idea underpinning this concept involves sequential triplet energy transfer from the TS to host and then to the annihilator, driven by the cascaded triplet energy landscape. Because of the small annihilator blend ratio, the local density of triplet excitons in the annihilator domain is higher than the overall density, leading to faster TTA. Based on the excitation-intensity and blend-ratio dependences of TTA-UC efficiency, we found that our concept has a positive impact on accelerating TTA.

Fine-tuning heat resistance and impact toughness of natural rubber-toughened PLA at Various degrees of PLA/PDLA stereocomplexation

This study represents a new investigation into the influence of stereocomplex crystal content within the blend system of natural rubber (NR) and polylactic acid (PLA), aiming to concomitantly enhance both the impact strength and thermal properties of PLA. The NR content was fixed at 15 wt%, while the amount of stereocomplex crystals was increased by adjusting the PLA:PDLA ratio from 100:0 to 50:50 corresponding to the PDLA content ranging from 0 – 42.5 wt%. Regarding the effect of NR alone, the incorporation of well-dispersed NR into PLA resulted in a significant improvement in the impact strength with a slight increase in heat resistance of PLA as NR acted not only as a toughening agent but also as a mild nucleating agent for PLA. The addition of PDLA, especially at higher contents, provided higher % crystallinity and crystallization rate of stereocomplex crystals, consequently enhancing the heat resistance of the blends. At the optimal PDLA content of 30 wt%, the molded specimens could successfully withstand a temperature of 100 °C throughout the 24-hour test with a 3-fold higher impact strength than that of neat PLA.

Study on Blending Modification of Bisphenol A Epoxy.

Epoxy-resin-based composites in the field of current electrical materials often work in high temperature, high humidity or salt spray conditions. In order to improve the operation reliability of the composite insulator cross arm in a high temperature, high humidity and high salt spray environment, and analyze the aging mechanism and performance characteristics of resin, in this paper, wet heat aging and salt spray aging experiments were carried out on the blended resin system composed of bisphenol A type epoxy resin (E-51), aliphatic epoxy modified bisphenol A epoxy resin (2021P/E-51) and dimeric acid modified bisphenol A epoxy resin (EPD-172/E-51). Among them, 10 wt% and 20 wt% of 2021P blend resin and 10 wt% of EPD blend resin have superior thermo-mechanical properties. Under humid and hot conditions, the dielectric loss of 10 wt% EPD blend system before and after aging is 39.9% and 49.5% lower than that of pure E51 resin system, respectively. Under the condition of salt spray, the dielectric loss of 20 wt% and 10 wt% EPD blends decreased by 73.1% and 74.6% after aging. The leakage current of 10 wt% 2021P blend resin and 10 wt% EPD blend resin decreased by 7% and 3.8% before aging, respectively. After aging, they decreased by 3.7% and 2.2%, respectively. The bending strength of 2021P blend resin before and after aging reached 29.3 MPa and 26.6 MPa, respectively. The above three blending resin systems exhibit good electrical properties and good mechanical properties, their ageing resistance performance is strong and they are suitable as the matrix resin of compound cross arm mandrel material.

Influence of TPU/EVA Phase Morphology Evolution on Supercritical Carbon Dioxide Extrusion Foaming.

Ethylene-vinyl acetate copolymer (EVA) was added at different contents to the thermoplastic polyurethane (TPU) matrix to form a non-compatible blending system, and foaming materials with high pore density were prepared using the supercritical carbon dioxide extrusion method. The influence of the phase morphology and crystal morphology of the TPU/EVA blend on its foaming behavior was studied. The results show that EVA changed the phase morphology and crystal morphology of the blends, leading to the improved melt viscosity and crystallinity of the blend system. At the same time, interfacial nucleation increases the density of cells and decreases the cell thickness and size, which is beneficial for improving the foaming properties of the blends. For the EVA content of 10% (mass fraction), the cell size is small (105.29 μm) and the cell density is the highest (3.74 × 106 cells/cm3). Based on the TPU/EVA phase morphology and crystal morphology, it is found that the sea-island structure of the blend has better foaming properties than the bicontinuous structure.

Biodegradable block copolymer as compatibilizer and blend component of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate)-based polyester blends

Atactic poly(3-hydroxybutyrate) (PHB)-b-poly(ε-caprolactone) (PCL) diblock copolymer, a type of biodegradable block copolymer (BCP) was selected as compatibilizer for poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH)/PCL immiscible blends. The additive effect of BCP on the morphologies and mechanical properties was dependent on the blend composition of PHBH/PCL. For 80/20 (w/w) PHBH/PCL blends, the incorporation of BCP did alter their mechanical properties by the increase in elongation at break with increasing BCP amount. However, the addition of BCP for 60/40 (w/w) PHBH/PCL blends were not greatly affected on their morphologies and mechanical properties. When BCP was used as one of binary blend components, the mechanical properties were significantly changed depending on the blend composition. PHBH/BCP blends also showed promising improvement in terms of mechanical performance. Presence of BCP in the ternary and binary blend systems decreased the enzymatic degradation rate by PHB depolymerase.

Thermoplastic polyurethane-based shape memory polymers with potential biomedical application: The effect of TPU soft-segment on shape memory effect and cytocompatibility

Stimuli-responsive biocompatible polymer blends with adjustable properties are highly desirable for biomedical applications. It is crucial to meticulously consider the chemical structure and composition of each polymer to prepare a melt-miscible blend system that possesses desirable shape memory and cytocompatibility performance. Herein, we developed thermo-responsive SMPs by melt-blending Polycaprolactone (PCL) with two different Thermoplastic polyurethanes (TPU) composed of the same hard segment, but different soft segments derived from adipic acid polyester and polycaprolactone diols and the critical role of TPU chemical structure on the thermomechanical properties and biocompatibility of TPU-based SMPs were investigated and uncovered. Cyclic thermomechanical tests show that compared with adipic acid-based TPU/PCL blends, PCL diol-based TPU/PCL blends exhibit remarkable shape memory properties (Rf and Rr >90%) with the ability to start recovery at lower temperatures (∼45 °C), while the cytotoxicity and wettability studies implied higher biocompatibility and hydrophilicity of adipic acid-based TPU/PCL blends making them more favorable substrates for cell proliferation.