Polypropylene (PP) blends with acrylonitrile‐butadiene‐styrene (ABS) were prepared using the styrene‐ethylene‐butylene‐styrene copolymer (SEBS) as a compatibilizing agent. The blends were prepared in a co‐rotational twin‐screw extruder and injection molded. Torque rheometry, Izod impact strength, tensile strength, heat deflection temperature (HDT), differential scanning calorimetry, thermogravimetry, and scanning electron microscopy properties were investigated. The results showed that there was an increase in the torque of PA6/ABS blends with SEBS addition. The PP/ABS/SEBS (60/25/15%) blend showed significant improvement in impact strength, elongation at break, thermal stability, and HDT compared with neat PP. The elastic modulus and tensile strength have not been significantly reduced. The degree of crystallinity and the crystalline melting temperature increased, indicating a nucleating effect of ABS. The PP/ABS blends compatibilized with 12.5% and 15% SEBS presented morphology with well‐distributed fine ABS particles with good interfacial adhesion. As a result, thermal stability has been improved over pure PP and the mechanical properties have been increased, especially impact strength. In general, the addition of the SEBS copolymer as the PP/ABS blend compatibilizer has the advantage of refining the blend's morphology, increasing its toughness and thermal stability, without jeopardizing other PP properties.

Tin dioxide (SnO 2) gas sensors with reliable sensing properties and low-cost are most desired for application in the detection of hazardous gases in heavy industries, 1,2 in-house safety monitoring, 3 and food quality control. 4 Most SnO 2based gas sensors are formed by a single heated layer of sensing material deposited over a pair of electrodes, which usually needs high operating temperatures (200-400ºC) to achieve their most desirable sensing response. 3,

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In this work, polyamide 6 (PA6) properties were tailored and improved using a maleic anhydride-grafted acrylonitrile-butadiene-styrene terpolymer (ABS-MA). The PA6/ABS-MA blends were prepared using a co-rotational twin-screw extruder. Subsequently, the extruded pellets were injection-molded. Blends were characterized by torque rheometry, the Molau test, Fourier transform infrared spectroscopy (FTIR), impact strength, tensile strength, Heat Deflection Temperature (HDT), Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Contact Angle, Scanning Electron Microscopy (SEM), and water absorption experiments. The most significant balance of properties, within the analyzed content range (5, 7.5, and 10 wt.%), was obtained for the PA6/ABS-MA (10%) blend, indicating that even low concentrations of ABS-MA can improve the properties of PA6. Significant increases in impact strength and elongation at break have been achieved compared with PA6. The elastic modulus, tensile strength, HDT, and thermal stability properties of the PA6/ABS-MA blends remained at high levels, indicating that maleic anhydride interacted with amine end-groups of PA6. Torque rheometry, the Molau test, and SEM analysis suggested interactions in the PA6/ABS-MA system, confirming the high properties obtained. Additionally, there was a decrease in water absorption and the diffusion coefficient of the PA6/ABS-MA blends, corroborating the contact angle analysis.

Magnetic and flexible nanocomposites of polyamide 6 (PA6)/styrene-(ethylene-butylene)-styrene grafted with maleic anhydride (SEBS-MA) were prepared using Ni-Zn ferrite synthesized by combustion reaction. Thermal treatment was applied to the Ni-Zn ferrite to form a more crystalline phase.The nanocomposites were processed in an internal mixer and later injection molded. The materials were characterized by torque rheometry, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Izod impact strength, tensile strength, magnetic measurements, differential scanning calorimetry (DSC), thermogravimetry (TG), heat deflection temperature (HDT), and scanning electron microscopy (SEM). Ferrite calcination led to a higher degree of crystallinity and nanocomposites with a higher number of crystalline peaks. This favored a higher saturation magnetization. The magnetic hysteresis curves of the nanocomposites indicated a ferrimagnetic behavior. The impact strength and elongation at break increased significantly compared to neat PA6, suggesting the formation of flexible and magnetic nanocomposites. This behavior was ascribed to a chemical reaction between the terminal amine groups of PA6 and the maleic anhydride of SEBS-MA, confirmed by FTIR and torque rheometry. Neat PA6 and the nanocomposites showed similar thermogravimetric, HDT, melting temperature, and crystallization properties. SEM results showed that the dispersed ferrite tends to form agglomerates, especially if calcined. In general, the addition of the non-calcined Ni-Zn ferrite to the PA6 matrix improved the mechanical properties. Conversely, the calcination of ferrite tended to improve the magnetic behavior of the nanocomposites.

Herein, we prepared toughened and electrical nanocomposites of polyamide 6 (PA6)/acrylonitrile‐butadiene‐styrene (ABS) compatibilized with maleic anhydride‐grafted acrylonitrile‐butadiene‐styrene (ABS‐MA). Functionalized multi‐walled carbon nanotubes (MWCNTf) were used as conductive nanofillers. Nanocomposites were processed in an internal mixer and injection molded. Torque rheometry, impact strength, elastic modulus, heat deflection temperature (HDT), differential exploratory calorimetry (DSC), melting and crystallization kinetic curves, electrical conductivity, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were evaluated. Torque increased with the MWCNTf content in the PA6/ABS/ABS‐MA/MWCNTf nanocomposites, suggesting an increase in viscosity. The MWCNTf were well dispersed in the nanocomposites, generating an electrical percolation path. The impact strength of the PA6/ABS/ABS‐MA/MWCNTf nanocomposites was superior to that of pure PA6, indicating improved flexibility and toughness. The addition of 1 pcr of MWCNTf in the PA6/ABS/ABS‐MA system was sufficient for antistatic application, with a 221% higher impact strength, compared to pure PA6. The DSC studies showed that the crystallization temperature of the nanocomposites shifted to higher temperatures. This was due to the MWCNTf that accelerated crystallization. Additionally, the nanocomposites HDT increased by 20°C compared to the PA6 matrix, suggesting a superior thermomechanical strength. The developed nanocomposites show improved mechanical, electrical, and thermomechanical properties. Therefore, they exhibit great technological potential for application in antistatic packaging.

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The development of new ecological materials to promote sustainability is being encouraged. Crosslinked biopolyethylene (BioPE)/noni flour (Morinda citrifolia) biocomposites were prepared using maleic anhydride-grafted polyethylene (PE-g-MA) and dicumyl peroxide (DCP). The biocomposites were processed in an internal mixer and injection molded. Torque rheometry, Izod impact strength, tensile strength, heat deflection temperature (HDT), differential scanning calorimetry (DSC), thermogravimetry (TG), and scanning electron microscopy (SEM) properties were investigated. Torque rheometry curves suggest that the biocomposites did crosslink due to the DCP attack on the BioPE chain. The BioPE/noni flour/PE-g-MA formulation with 0.5% and 1% DCP produced a higher level of crosslinking. As a result, the mechanical properties (impact strength, elastic modulus, and tensile strength) were improved. SEM showed fractured noni flour particles in the BioPE matrix with the formation of a tubular structure. The HDT increased, suggesting that the biocomposites exhibit enhanced thermomechanical strength. Furthermore, the biocomposites thermal properties obtained by DSC underwent few modifications. The TG results showed that the crosslinked biocomposites have better thermal stability than the noncrosslinked biocomposites. The crosslinking process of BioPE/noni flour biocomposites with the PE-g-MA/DCP hybrid is an effective way to improve the performance of these materials.