Polystyrene/EVA melt blends compatibilized with EVA-graft-polystyrene

The influence of poly[(ethylene-co-vinyl acetate)-g-polystyrene] (EVA-g-PS) on the mechanical and morphological properties of polystyrene and the blends with EVA copolymers has been investigated. The melt blends have been performed in a twin-screw extruder. The addition of the graft copolymer enhances the mechanical properties and impact resistance of the PS matrix and PS/EVA (90 : 10 wt %) blends. Better results on impact strength and elongation at break have been achieved by using a EVA-g-PS graft copolymer with a higher EVA proportion by weight. This graft copolymer also contains a lower molecular weight of the PS-grafted segments than the PS matrix. Morphological studies by scanning electron microscopy revealed some interfacial adhesion between the components in the compatibilized polymer blends. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 2141–2149, 1997     

Studies on polymer blends with moderate specific interactions 1. Mechanical properties of SAN/TPU and SAN/EVA/TPU

Polymer pairs with moderate specific interactions may lead to phases with low interfacial energy, which is desirable for rubber-toughening plastics. SAN and some polyurethane elastomers (TPU) belong to this kind of system. Without adding compatibilizer, SAN/TPU blends possess excellent mechanical properties. However, SAN and EVA form mechanically incompatible blends. The properties of the SAN/EVA blends can be substantially improved by incorporating TPU. Scanning electron microscopy (SEM) observations prove that TPU acts as a compatibilizer preferentially locating at the interface.     

Reactively compatibilised polyamide6/ethylene-co-vinyl acetate blends: mechanical properties and morphology

Mechanical properties and morphological studies of compatibilised blends of PA6/EVA-g-MA and PA6/EVA/EVA-g-MA were studied as functions of maleic anhydride content (MA) and dispersed phase (EVA-g-MA) concentrations, respectively at blending composition of 20 wt% dispersed phase (EVA-g-MA or combination of EVA and EVA-g-MA). The maleic anhydride (MA) was varied from 1 to 6 wt% in the PA6/EVA-g-MA blend, whereas MA concentration was fixed at 2 wt% in the ternary compositions with varying level of EVA-g-MA. ATR-IR spectroscopy revealed the formation of in situ copolymer during reactive compatibilisation of PA6 and EVA-g-MA. It was found that notched Izod impact strength of PA6/EVA-g-MA blends increased significantly with MA content in EVA-g-MA. The brittle to tough transition temperature of reactively compatibilised blends was found to be at 23 °C. The impact fractured surface topology reveals extensive deformation in presence of EVA-g-MA whereas; uncompatibilised PA6/EVA blend shows dislodging of EVA domains from the matrix. Tensile strength of the PA6/EVA-g-MA blends increased significantly as compared to PA6/EVA blends. Analysis of the tensile data using predictive theories showed an enhanced interaction of the dispersed phase and the matrix. It is observed from the phase morphological analysis that the average domain size of the PA6/EVA-g-MA blends is found to decrease gradually with increase in MA content of EVA-g-MA. A similar decrease is also found to observe in PA6/EVA/EVA-g-MA blends with increase in EVA-g-MA content, which suggest the coalescence process is slower in presence of EVA-g-MA. An attempt has been made to correlate between impact strength and morphological parameters with regard to the compatibilised system over the uncompatibilised system.     

The Effect of Epoxidized Natural Rubber (ENR-50) or Polyethylene Acrylic Acid (PEA) as Compatibilizer on Properties of Ethylene Vinyl Acetate (EVA)/Natural Rubber (SMR L) Blends

The effect of epoxidized natural rubber (ENR) or polyethylene acrylic acid (PEA) as a compatibilizer on properties of ethylene vinyl acetate (EVA)/natural rubber (SMR L) blends was studied. 5 wt.% of compatibilizer was employed in EVA/SMR L blend and the effect of compatibilizer on tensile properties, thermal properties, swelling resistance, and morphological properties were investigated. Blends were prepared by using a laboratory scale of internal mixer at 120°C with 50 rpm of rotor speed. Tensile properties, thermal properties, thermo-oxidative aging resistance, and oil swell resistance were determined according to related ASTM standards. The compatibility of EVA/SMR L blends with 5 wt.% of compatibilizer addition or without compatibilizing agent was compared. The EVA/SMR L blend with compatibilizer shows substantially improvement in tensile properties compared to the EVA/SMR L blend without compatibilizer. Compatibilization had reduced interfacial tension and domain size of ethylene vinyl acetate (EVA)/natural rubber (SMR L) blends.     

Studies on polymer blends with moderate specific interactions. 2. phase structure of blends SAN/TPU and SAN/TPU/EVA

This paper deals with morphological studies of binary and ternary blends composed of poly(styrene-co-acrylonitrile) (SAN), polyurethane elastomer (TPU) and poly(ethylene-co-vinyl acetate) (EVA). Selective etching was found necessary to expose the morphologies of the blends. Chloroform or hot acetone, hexane/toluene (2/1v/v) and NaOH/CH₃OH (1wt%) were found to be selective etching agents for SAN, EVA and TPU, respectively. SAN and TPU form blends with fine dispersion structure, while SAN and EVA lead to rough phase structure with poor phase adhesion. These results are in accordance with the difference in the mechanical properties of SAN/TPU and SAN/EVA. In addition, for SAN/TPU/EVA blends, if TPU is only a minor component, it is preferentially located at the interphase, playing the role of a compatibilizer. As the amount of TPU increases, the compatibility is gradually improved. ©1997 SCI     

Influence of the morphology and viscoelasticity on the thermomechanical properties of poly(lactic acid)/thermoplastic polyurethane blends compatibilized with ethylene-ester copolymer

Viscoelastic, interfacial properties, and morphological data were employed to predict the thermal and mechanical properties of compatibilized poly(lactic acid) (PLA)/thermoplastic polyurethane (TPU) blends. The combination of interfacial thickness measured by contact angle and entanglement density determined by dynamical mechanical analysis analyze data was employed to evaluate the mechanical behavior of PLA/TPU blends with and without ethylene-butyl acrylate-glycidyl methacrylate (EBG) compatibilization agent. The PLA/TPU blend (70/30 wt %) was prepared in a Haake internal mixer at 190 °C and compatibilized with different contents of EBG. The evaluation of the interfacial properties revealed an increase in the interfacial layer thickness of the PLA/TPU blend with EBG. The scanning electronic microscopy images showed a drastic reduction in the size of the dispersed phase by increasing the compatibilizer agent EBG content in the blend. The compatibilization of the PLA/TPU blends improved both the Izod impact strength and yield stress by 38 and 33%, respectively, in comparison with neat PLA/TPU blend. The addition of EBG into PLA/TPU blends significantly increased the entanglement density and the PLA toughening but resulted in a decrease of PLA deformation at break. The PLA and TPU glass transitions were affected by the EBG, suggesting that the PLA and TPU domains were partially miscible. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48926.     

A new method in designing compatibility and adhesion of EVA/PMMA blend by using EVA-<Emphasis Type="Italic">g</Emphasis>-PMMA with controlled graft chain length

Atom transfer free radical polymerization (ATRP) was employed in a synthesis of graft polymer EVA-g-PMMA with controlled length of side PMMA chains. Three steps of synthesis: partial hydrolysis of EVA, esterification with chloroacetyl chloride and ATRP grafting were performed to produce EVAOH, macroinitiator EVACl and grafted polymers G8020 (EVA/PMMA?=?80/20 wt%) and G6040 (EVA/PMMA?=?60/40 wt%). FTIR, Raman and NMR spectroscopy were used in the determination of the chemical structure and modification of EVA. Transmitted light and dark field microscopy showed higher affinity for coil formation of EVA-g-PMMA with longer PMMA side chains, i.e. G6040 compatibilizer. Morphological, thermal and adhesive properties of optical fiber adhesives of graft polymers and polymer blends poly(ethylene-co-vinyl acetate)-blend-poly(methyl methacrylate) (EVA/PMMA) compatibilized with 1 wt% of EVA-g-PMMA, were studied. Image analysis of SEM micrographs showed effective compatibilization with short grafted chains (G8020) that was indicated by lower porosity characteristics. TG/DTG analysis enabled determination of degree of hydrolysis and amount of chloro-functionalized groups. DSC analysis showed higher thermal stability of G8020 polymer. Single lap joint of adhesives/optical fibers were subjected to adhesive testing and obtained results for maximal force applied and adhesive failure suggested the visible influence of the length of graft chains on adhesion.     

Study on thermoplastic polyurethane/polypropylene (TPU/PP) blend as a blood bag material

Blends with different ratios of thermoplastic polyurethane/polypropylene (TPU/PP) were prepared by melt mixing using an internal Haake mixer. Properties of the blends were investigated using SEM micrographs of cryofractures and measurement of the mechanical strength, water absorption, cell culture, and platelet adhesion in vitro tests, which were compared with those of PVC blood bags. The effect of the addition of the ethylene–vinyl acetate (EVA) copolymer on the TPU/PP blend properties was investigated. The results indicated that a TPU/PP/EVA = 80/20/5 blend can be used as a new blood bag material. It was observed that the blend is homogeneous with higher mechanical strength than that of the commercial PVC blood bag. This blend also showed a compatible cell response in contact with L929 fibroblast cells and fewer tendencies to interaction with platelets compared to the PVC blood bag. Although the blends were immissible and no chemical reaction at the interface could be found, the blood compatibility of the blends were improved. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2496–2501, 2003     

Effect of interfacial interaction on the crystallization and mechanical properties of PP/nano‐CaCO3 composites modified by compatibilizers

To investigate the effect of interfacial interaction on the crystallization and mechanical properties of polypropylene (PP)/nano‐CaCO₃ composites, three kinds of compatibilizers [PP grafted with maleic anhydride (PP‐g‐MA), ethylene–octene copolymer grafted with MA (POE‐g‐MA), and ethylene–vinyl acetate copolymer grafted with MA (EVA‐g‐MA)] with the same polar groups (MA) but different backbones were used as compatibilizers to obtain various interfacial interactions among nano‐CaCO₃, compatibilizer, and PP. The results indicated that compatibilizers encapsulated nano‐CaCO₃ particles, forming a core–shell structure, and two interfaces were obtained in the compatibilized composites: interface between PP and compatibilizer and interface between compatibilizer and nano‐CaCO₃ particles. The crystallization and mechanical properties of PP/nano‐CaCO₃ composites were dependent on the interfacial interactions of these two interfaces, especially the interfacial interaction between PP and compatibilizer. The good compatibility between PP chain in PP‐g‐MA and PP matrix improved the dispersion of nano‐CaCO₃ particles, favored the nucleation effect of nano‐CaCO₃, increased the tensile strength and modulus, but reduced the ductility and impact strength of composites. The partial compatibility between POE in POE‐g‐MA and PP matrix had little effect on crystallization and mechanical properties of PP/nano‐CaCO₃ composites. The poor compatibility between EVA in EVA‐g‐MA and PP matrix retarded the nucleation effect of nano‐CaCO₃, and reduced the tensile strength, modulus, and impact strength. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Toughness improvement of poly(lactic acid) with poly(vinyl propionate)-grafted natural rubber

Natural rubber (NR) grafted with poly(vinyl propionate) (NR-g-PVP) was prepared by emulsion polymerization. The monomer content was set at 5, 10, 20, and 30 wt%. The chemical structure of NR-g-PVP was confirmed by ¹H-NMR and FTIR techniques. The grafting parameters of purified NR-g-PVP were evaluated. Binary (PLA/NR and PLA/NR-g-PVP) and ternary (PLA/NR/NR-g-PVP) blends were prepared by melt blending using a twin-screw extruder. The percentage of grafted PVP on NR affected morphology, thermal and mechanical properties of the blends. In binary blends, 5% grafting showed the greatest improvement of toughness and ductility with PLA, whereas there was no improvement in the mechanical properties of PLA/NR blend from using NR-g-PVP as a compatibilizer. The mechanical properties of the blends are related to mutual compatibility of the components. Good interfacial adhesion and proper particle size of NR were the key factors contributing to mechanical properties.     

Studies on polycarbonate/polystyrene/polycarbonate- graft-polystyrene blends. II. Compatibility and morphology of PC/PS/PC-g-PS blends

A radiation grafted copolymer of polycarbonate (PC) and polystyrene (PS) was used as a compatibilizer of PC/PS melt blends. The compatibility and morphology of PC/PS/PC-g-PS blends were studied by differential scanning calorimetry and scanning electron microscopy. As a consequence of the addition of PC-g-PS, the compatibility of PC/PS blends was improved; the dimensions of the dispersed phases and the interfacial tension between the two phases were reduced. Additionally, stabilization against gross segregation and interfacial adhesion of the blends were also improved by adding PC-g-PS as a compatibilizer. © 1998 SCI.     

The role of nanofillers on (natural rubber)/(ethylene vinyl acetate)/clay nanocomposite in blending and foaming

Nanocomposite foams were fabricated from 60/40 wt% ethylene vinyl acetate (EVA)/natural rubber (NR) blends by using azodicarbonamide as a blowing agent. Two different nanofillers (sodium montmorillonite and organoclay) were employed to study their effects on foam properties. The results were also compared with conventional (china clay)‐filled foams. Transmission electron microscopy, X‐ray diffraction, scanning electron microscopy, and three‐dimensional Microfocus X‐ray computed tomography scanning analysis were performed to characterize the EVA/NR blend morphology and foam structures. The results revealed that the nanofiller acted as a blend compatibilizer. Sodium montmorillonite was more effective in compatibilization, generating better phase‐separated EVA/NR blend morphology and improving foam structure. Higher filler loading increased the specific tensile strength of rubber foams. The rubber nanocomposite foam showed superior specific tensile strength to the conventional rubber composite foam. The elastic recovery and compressive strength of the nanocomposite foams decreased with increasing filler content, whereas the opposite trend was observed for the conventional composite foams with china clay. The thermal conductivity measurement indicated that the nanofiller had better beneficial effect on thermal insulation over china clay filler. From the present study, the nanofillers played an important role in obtaining better blend morphology as compatibilizer, rather than the nucleating agent and the nanofiller content of 5 phr (parts by weight per hundred parts of rubber) was recommended for the production of EVA/NR nanocomposite foams. J. VINYL ADDIT. TECHNOL., 21:134–146, 2015. © 2014 Society of Plastics Engineers     

Poly(butylene terephthalate)/poly(ethylene glycol) blends with compatibilizers

Polymer blend systems offer a versatile approach for tailoring the properties of polymer materials for specific applications. In this study, we investigated the compatibility of polybutylene terephthalate (PBT) and poly(ethylene glycol) (PEG) blends processed using a twin-screw extruder, with the aim of enhancing their compatibility. Phthalic anhydride (PAn) and phthalic acid (PAc) were used as potential compatibilizers at different concentrations to improve interfacial interactions between PBT and PEG. Blend morphologies were characterized using scanning electron microscopy, which revealed improved interfacial compatibility and reduced phase separation with the incorporation of small amounts of PAn and PAc. Differential scanning calorimetry analysis indicated changes in the melting temperature (T_m) and glass transition temperature (T_g) of the blends owing to the compatibilizing effects of PAn and PAc. Dynamic mechanical analysis further corroborated the influence of the compatibilizers on the T_g and viscoelastic behavior. Thermogravimetric analysis demonstrated enhanced thermal stability with the addition of either PAn or PAc. Rheological measurements indicated an increase in complex viscosity with increasing compatibilizer content, indicating improved compatibility. The degradation point (T_d) of PBT/PEG blend increased from 158 to 200 and 319°C with the incorporation of 5 phr PAn and 2 phr PAc, respectively. Mechanical properties, including tensile strength, Young's modulus, and Izod impact strength, were evaluated. For instance, the tensile strength of PBT/PEG blend was enhanced from 43.5 to 48.7 and 49.7 MPa by incorporating 5 phr PAn and 2 phr PAc, respectively. However, the impact strength of PBT/PEG blend increased from 3.0 to 4.3 and 4.2 kJ/m² with the addition of 1 phr PAn and 1 phr PAc, respectively. The findings demonstrated that adding 5 phr PAn or 2 phr PAc to the PBT/PEG blends was advantageous, achieving a harmony of performance benefits and compromises. Rheological observations contributed significantly to the mechanical and thermal properties. Overall, the study highlights the significance of utilizing PAn and PAc as effective compatibilizers for enhancing the properties of PBT/PEG blends, making them potential candidates for various applications.     

含异氰酸酯基的低聚物和聚醚增容改性POM/TPU共混物

利用双螺杆挤出机制备了聚甲醛(POM)/热塑性聚氨酯弹性体(TPU)、POM/TPU/含异氰酸酯基的低聚物(Z)以及POM/TPU/Z/聚醚3种共混物。采用力学性能测试、差示扫描量热分析(DSC)、偏光显微镜(PLM)、傅里叶转换红外线光谱 (FTIR)、扫描电子显微镜(SEM)、动态力学性能分析(DMA)等,研究了3种共混物的力学性能、结晶行为及形态结构。结果表明：共混物的缺口冲击强度和断裂伸长率随TPU含量的增加而提高;异氰酸酯基低聚物（Z）和聚醚在促进分散相分散、增强两相间的相容性方面发挥重要作用,降低了聚甲醛的结晶度,能够有效地提高共混物的缺口冲击强度和断裂伸长率。     

Properties and preparation of olefin block copolymer/thermoplastic polyurethane blends

The properties of olefin block copolymer (OBC)/thermoplastic polyurethane (TPU) blends with or without maleic anhydride (MA) modification were characterized and compared. Compared with the OBC/TPU blends, OBC‐g‐MA/TPU blends displayed finer morphology and reduced domain size in the dispersed phase. The crystallization temperatures of TPU decreased significantly from 155.9 °C (OBC/TPU) to 117.5 °C (OBC‐g‐MA/TPU) at low TPU composition in the blends, indicating the inhibition of crystallization through the sufficient interaction of modified OBC with TPU composition. The modified systems showed higher thermal stability than the unmodified systems over the investigated temperature range due to the enhanced interaction through inter‐bonding. The highest improvement in tensile strength was more than fivefold for OBC‐g‐MA/TPU (50/50) in comparison with its unmodified blend via the enhanced interfacial interaction between OBC‐g‐MA and TPU. This also led to the highest Young's modulus of 77.8 ± 3.9 MPa, about twofold increase, among the investigated blend systems. A corresponding improvement on the ductility was also observed for modified blends. The modification did not vary the glass transition temperature and crystalline structure much, thus the improvement in the mechanical properties was mainly attributed to the improved compatibility and interaction from the compatibilization effect as well as increased viscosity from the crosslinking effect for modified blends. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43703.     

In situ reactive compatibilization in polymer blends: Effects of functional group concentrations

Polystyrene (PS) and polyethylene (PE), along with their reactive counterparts, i.e., polystyrene having oxazoline reactive groups (OPS) and polyethylene with carboxylic acid groups (CPE), were melt blended in a Rheomix mixer. These blends were prepared by mixing these polymers in various proportions under a variety of conditions. In an alternate procedure the OPS, CPE graft polymer (OPS-g-CPE) was prepared by melt blending these two polymers beforehand, and subsequently this grafted polymer was used as a compatibilizer for PS–PE blends. The effects of the addition of OPS and CPE, on the one hand, and OPS-g-CPE, on the other hand, on the compatibility of PS–PE blends were investigated. The morphology of these blends was examined with a scanning electron microscope (SEM) and related to their tensile properties. The PS–PE blends are found to have the typical coarse morphology of incompatible blends and poor tensile properties while their reactive counterparts, OPS-CPE blends, have fine grain microstructure and show improved tensile strength throughout the range and improved elongation in the PE-rich blends. Relatively low concentrations of the reactive pair, oxazoline and carboxylic acid, are shown to be necessary to produce improved compatibility. The preblended graft copolymer OPS-g-CPE imparts compatibility to PS–PE blends also but not as effectively. This suggests that the addition of OPS and CPE during melt mixing of PS and PE forms OPS-g-CPE polymer at the interface and that these ingredients act as “in situ reactive compatibilizers” which improve physical properties.     

Mechanical and sorption properties of poly(ethylene-co-vinyl acetate)(EVA) compatibilized acrylonitrile butadiene rubber/natural rubber blend systems

Poly (ethylene-co-vinyl acetate) (EVA) has been used as a compatibilizer for heterogeneous natural rubber/acrylonitrile butadiene rubber (NR/NBR) blends. NR/NBR (50/50) blends were compatibilized with varying amounts, from 0 to 10 parts per hundred rubber (phr), of EVA. The compatibility of the blend components in presence of EVA has been evaluated in terms of mechanical and sorption characteristics. The mechanical properties were found to be improved by the addition of EVA upto 6 phr. The solvent resistance of the compatibilized samples has been observed to be higher compared to the uncompatibilized blends; attributed to the increased interfacial adhesion between the blend components. DSC studies showed a shift of glass transition temperatures of the blend components towards higher temperatures indicating increased rigidity of the matrix in presence of EVA.     

Novel thermoplastic natural rubber based on thermoplastic polyurethane blends: influence of modified natural rubbers on properties of the blends

Three different forms of natural rubber: maleated natural rubber (MNR), epoxidized natural rubber (ENR) and natural rubber-graft-poly(methyl methacrylate) (NR-g-PMMA) were prepared. Degree of functional groups in rubber molecules was quantified using the integrated peak areas of ¹H NMR. It was found that the modified rubbers with similar level of functionality had been successfully prepared. Thermoplastic natural rubber (TPNR) based on blending of thermoplastic polyurethane (TPU) and various forms of rubber were then prepared using melt blending method. The properties of the blends were studied and compared together in relation to different types of natural rubbers prepared (i.e., unmodified NR, MNR, ENR and NR-g-PMMA). It was found that the blends with modified NR exhibited superior stiffness, entropy effect and damping factor compared to other blends with unmodified NR. This is attributed to the chemical interaction between the functional groups of modified NR molecules and polar functional groups in TPU molecules which facilitated higher interfacial adhesion between both phases. The chemical interaction was verified by ATR-FTIR and TSSR techniques. It was also found that the MNR/TPU blend showed the highest tensile modulus, mechanical and elastic properties with smallest and finer grain dispersion of co-continuous phase compared to ENR/TPU, NR-g-PMMA/TPU and unmodified NR/TPU blends, respectively. This might be due to higher chemical interactions between MNR and TPU phases. Furthermore, the incorporation of rubber did reduce hardness (i.e., <60 Shore A) with improvement of elasticity of the blends compared with the original TPU (i.e., ~85 Shore A).     

Ethylene vinyl acetate as compatibilizer on cure characteristics and mechanical properties of (natural rubber)/(Recycled acrylonitrile‐butadiene rubber) blends

Ethylene vinyl acetate (EVA) has been used as a compatibilizer for (natural rubber)/(recycled acrylonitrile‐butadiene rubber) (NR/NBRr) blends, vulcanized by sulfur. EVA offers excellent heat, ozone, and weather resistance, whereas the vinyl acetate groups provide oil resistance to the blend. It exhibits good tear resistance and may be crosslinked. However, EVA exhibits poor low‐temperature flexibility. NBR gloves have excellent resistance to punctures, tears, and many types of chemicals, while NR has good physical and mechanical properties. NR/NBRr blends were prepared with various compositions with the EVA content fixed. Tensile properties, hardness, and swelling behavior tests were performed to determine the compatibility of NR/NBRr blends in the presence of EVA. Results indicated that incorporation of EVA into NR/NBRr blends improved tensile strength, modulus, and elongation at break compared with NR/NBRr blends without EVA. The improvement in hardness and reduction in resilience on compatibilization are due to an increase in crosslink density, which gives NR/NBRr blends better swelling resistance. Scanning electron microscopy of the fracture surfaces indicates that, with the addition of EVA in NR/NBRr blends, better adhesion between NR and NBRr was obtained, thus improving the compatibility of NR/NBRr blends. J. VINYL ADDIT. TECHNOL., 23:135–141, 2017. © 2015 Society of Plastics Engineers     

Interaction of thermoplastic polyurethane with polyamide 1212 and its influence on the thermal and mechanical properties of TPU/PA1212 blends

To improve the heat resistance of polyester‐based thermoplastic polyurethane (TPU), in the present work, polyamide 1212 (PA1212) was chosen as a modifier and a series of TPU/PA1212 blends with different compositions were prepared using a twin screw extruder. The solubility parameters, characteristic of chemical structures, hydrogen‐bonding interaction, as well as interfacial tension of the single component and blends were taken into account to describe the good compatibility of TPU/PA1212 blends. The effect of PA1212 content on the rheological behaviors, morphology, mechanical, and thermal properties of TPU/PA1212 blends were systematically investigated with scanning electron microscope, tensile strength measurement, thermal gravimetry analysis, differential scanning calorimetry, and Vicat softening temperature (VST). The results showed that PA1212 formed submicron dispersion domains in the TPU matrix, indicating good compatibility between TPU and PA1212. A slight increase of the tensile strength was achieved as PA1212 content is relatively low. Because of the strong hydrogen‐bonding interaction between TPU and PA1212, the thermal stability of the blends is improved, and VST values rise up from about 80 (pure TPU) to 100°C, showing attractive potential application. POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers