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In this study, recycled acrylonitrile-butadiene-styrene terpolymer (ABSr) was reused to produce polyamide 6 (PA6)-based blends. This was achieved through reactive compatibilization using styrene-acrylonitrile-maleic anhydride (SAN-g-MA) copolymer with a high degree of functionalization (6–10% MA). The PA6/ABSr and PA6/ABSr/SAN-g-MA blends were prepared through melt processing and injection molding and then analyzed for their rheological, mechanical, thermomechanical, thermal, and structural properties, as well as morphology. The torque rheometry revealed a maximum reactivity of the PA6/ABSr (70/30 wt%) blend with low SAN-g-MA (5 phr—parts per hundred resin) content, while above this threshold, torque began to decline, indicating compatibilizer saturation in the interface. These findings were further substantiated by the increase in complex viscosity and the lower melt flow index (MFI) of the PA6/ABSr/SAN-g-MA (5 phr) blend. The 5 phr SAN-g-MA reactive compatibilization of the PA6/ABSr blends significantly enhanced its impact strength, elongation at break, tensile strength, and heat deflection temperature (HDT) by 217%, 631%, 12.6%, and 9.5%, respectively, compared to PA6/ABSr. These findings are promising for the plastic recycling field, paving the way for the production of new tailor-made materials at a reduced price. [ABSTRACT FROM AUTHOR]

The production of plastic products from non-renewable raw materials, such as petroleum, damages the environment. Consequently, biocomposites have aroused interest from industry and researchers due to their ecologically correct characteristics, mainly because they come from renewable sources. Therefore, this study aimed to produce biopolyethylene/coffee ground waste (BioPE/CGW) biocomposites and analyze the impact of CGW and polyethylene-graft-maleic anhydride (PE-g-MA) on BioPE. The biocomposites were prepared in a co-rotational twin-screw extruder equipped with a side feeder to feed the CGW. The materials were subsequently injection molded to produce the impact, tensile, and HDT samples. The temperature profiles used during extrusion and injection were between 170 and 180°C. The BioPE and biocomposites were investigated for the vibrational (Infrared Spectroscopy - FTIR), thermal (differential scanning calorimetry), mechanical (tensile, impact, and hardness), thermomechanical (heat deflection temperature (HDT) and Vicat softening temperature (VST)), and morphological (scanning electron microscopy (SEM)) properties. The compatibilizer improved the interface between phases, promoting mechanical and thermomechanical improvements in the biocomposites. PE-g-MA promoted increments in tensile strength and elastic modulus of up to 38% and 25% in the BioPE/CGW30 and an increase of 44% in the elastic modulus compared to BioPE. The thermomechanical investigations showed that HDT increased by 8.8 and 3.3°C and VST increased by 2.5 and 6.6°C compared to BioPE and the BioPE/CGW30, respectively. Biocomposites from renewable and biodegradable sources align with a sustainable development concept. [ABSTRACT FROM AUTHOR]

Formulating polymer blends is of vital scientific and industrial interest because of their low cost and the possibility of producing new materials with tailored properties. In this research, polypropylene (PP)/acrylonitrile–butadiene–styrene (ABS) polymer blends were prepared using styrene-ethylene-butylene-styrene (SEBS) and styrene-ethylene-propylene (SEP) copolymers. The polymer blends were extruded and injection molded to evaluate the mechanical, rheological, thermal, and thermomechanical properties, infrared spectroscopy, and morphology. Incorporating SEBS and SEP copolymers into the PP/ABS blend increased the torque and reduced the melt flow index, indicating higher viscosity than the PP/ABS base system. As a result, improved compatibility of PP/ABS/SEBS and PP/ABS/SEP blends was achieved, thereby improving the mechanical properties of PP/ABS. However, the SEBS copolymer was more effective. Compared to neat PP, the PP/ABS/SEBS blend with 15% SEBS showed increases in impact strength, elongation at break, and heat deflection temperature (HDT) of 87%, 107%, and 7%, respectively. In addition, the elastic modulus and Shore D hardness were in line with neat PP, and thermal stability measured through thermogravimetry exceeded that of PP by 8 °C. Evidence of fractured ABS particles in the PP matrix was seen in the scanning electron microscopy (SEM) morphology, suggesting that SEBS migrated to the interface. SEBS also remained dispersed in the PP matrix, as confirmed by selective phase extraction, which favored a synergic effect of properties in the PP/ABS/SEBS blend (70/15/15%). This blend offered potential for applications such as toys, furniture accessories, packaging, and housewares. [ABSTRACT FROM AUTHOR]

The postconsumer waste of vulcanized styrene–butadiene rubber (SBRr) is a raw material rich in additives with potential reuse in the plastics processing industry. The present investigation evaluated the effectiveness of styrene–ethylene/butylene–styrene copolymer (SEBS) in the compatibilization of biopolyethylene (BioPE)/SBRr blends. The blends were processed in a twin-screw extruder and injection molded to evaluate the melt flow index (MFI), impact strength, tensile strength, Shore D hardness, thermogravimetry (TG), differential scanning calorimetry (DSC), and heat deflection temperature (HDT). Morphology was studied by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The BioPE/SBRr/SEBS blend (70/20/10 wt%) showed the lowest MFI, which indicates a higher viscosity and, consequently, higher compatibility that led to increments of 120% and 698.6% on impact strength and elongation at break, respectively, compared to the noncompatibilized system. The reduction in elastic modulus, tensile strength, and Shore D hardness confirmed the increased flexibility of the BioPE/SBRr/SEBS blends. Melting and crystallization properties of the polymer blends were comparable to the BioPE matrix, suggesting that 20 wt% SBRr content did not severely deteriorate the thermal behavior. SEM analysis showed that SEBS induced a morphology with extensive plastic deformation, confirming the high impact strength and elongation at break. BioPE/SBRr blends compatibilized with SEBS offer significant technological potential, indicating that SBRr can be introduced into the productive chain and contribute to sustainability. [ABSTRACT FROM AUTHOR]

Acrylonitrile‐EPDM‐styrene (AES) was applied as an impact modifier for poly(lactic acid) (PLA), and the combined effect of dicumyl peroxide (DCP) crosslinking and annealing heat treatment was investigated. Torque rheometry, melt flow index (MFI), mechanical properties (impact, tensile, and Shore D hardness), X‐ray diffraction (XRD), infrared spectroscopy (FTIR), heat deflection temperature (HDT), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were investigated. There was a considerable torque increment and fluidity drop in the PLA/AES/DCP blends caused by the crosslinking process and the formation of PLA‐g‐AES. Consequently, the impact strength and elongation at break properties improved. As an engineering terpolymer, AES was decisive in maintaining high elastic modulus, Shore D hardness, and HDT values. The PLA/AES/DCP (0.8 phr) composition leaned towards a synergism of mechanical properties, gaining 505.6% and 264.8% in impact strength and elongation at break, respectively, compared to neat PLA. FTIR and XRD analysis revealed high crystallinity, with samples presenting large crystals. The higher crystallinity had a deleterious effect on the mechanical properties of the PLA/AES/DCP blends. However, there was a marked improvement in HDT and higher toughness compared to PLA. The results before and after annealing the PLA/AES/DCP (0.8 phr) blend are promising for constructing new semi‐biodegradable materials for additive manufacturing. [ABSTRACT FROM AUTHOR]

Low‐density biopolyethylene (BioLDPE) ecocomposites added with particles of eggshell (ES) residue were produced using linear low‐density polyethylene grafted with maleic anhydride (LDPE‐g‐MA) as a compatibilizing agent. BioLDPE/ES and BioLDPE/ES/LDPE‐g‐MA compounds were processed in a twin‐screw extruder, and the specimens were injection molded. Torque rheometry increased and melt flow index reduced more prominently for the BioLDPE/LDPE‐g‐MA biocomposite with 20 phr ES, suggesting higher viscosity. Consequently, there was a higher level of ES particles breakdown, generating greater distribution and dispersion, as verified in optical microscopy and scanning electron microscopy images. This finding was supported by Fourier transform infrared spectroscopy, considering the intense absorption band at 871 cm−1 for BioLDPE/ES (20 phr)/LDPE‐g‐MA biocomposite, indicating a higher level of ES particles dispersion in BioLDPE matrix. Therefore, BioLDPE/ES (20 phr)/LDPE‐g‐MA biocomposite increased the elastic modulus, tensile strength, Shore D hardness, and heat deflection temperature by 51.4%, 16.9%, 16.4%, and 14, 6%, respectively, related to BioLDPE. Additionally, the flexibility was kept as seen in the elongation at break and impact strength, including not fractured during the impact test. Reported results for the biocomposites are valuable mainly for the polymer additive sector, since the ES has the potential to improve BioLDPE properties, expanding the range of applications. [ABSTRACT FROM AUTHOR]

High‐performance blends based on polyamide 6 (PA6) were prepared using a hybrid mixture of acrylonitrile/EPDM/styrene (AES) and maleic anhydride grafted ethylene–propylene–diene (EPDM‐MA). Samples were processed in a twin‐screw extruder and injection molded. The torque curves of the PA6/AES/EPDM‐MA blends shifted to higher torque values with added EPDM‐MA, suggesting a chemical interaction between the components. The melt flow index (MFI) results for the PA6/AES/EPDM‐MA blends confirmed the intensification of the flow resistance. Intense infrared absorption peaks for NH and CO indicated that the amine groups of PA6 reacted with the maleic anhydride in EPDM‐MA. The 60/25/15 wt% PA6/AES/EPDM‐MA blend showed an impact strength over 800 J/m, heat deflection temperature (HDT) of 62.3°C, elongation at break of 115%, and contact angle of 59.1°, corresponding to increases of 1718%, 10.5%, 297%, and 10%, respectively, compared to neat PA6. When examined by scanning electron microscopy, the morphology showed a fracture surface with a high degree of plastic deformation and the formation of elastic microfibrils, contributing to the super toughening of the PA6/AES/EPDM‐MA (15%) system. These results indicate the technological potential of the PA6/AES/EPDM‐MA (15 wt%) blends for application in industrial sectors that require super‐tough plastics. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) has been gaining prominence in academia and industry, mainly due to being a biopolymer and biodegradable material. Nevertheless, mainly due to its high fragility, work has been carried out in order to seek alternatives to improve this drawback. Hence, this work aims to evaluate the effect of the vinyl acetate content using two types of EVA (EVA1 with 28% and EVA2 with 19%) in dynamically vulcanized PLA/EVA blends, using several dicumyl peroxide (DCP) contents, that is, 0.3, 0.5, and 0.7 phr. Blends were produced using an internal mixer, and the tensile, impact and HDT specimens were injection molded. By FTIR and torque rheometry, it was verified that, upon DCP addition, there was evidences of reticulation, resulting in crosslinked PLA, crosslinked EVA, as well as PLA‐g‐EVA. Through tensile and impact strength tests, it was observed substantial increases in the elongation at break, and in impact strength, mainly for the compounds with higher content of vinyl acetate (EVA1). Impact specimens made with PLA/EVA120 0.7 DCP, PLA/EVA130 0.5 DCP, and 0.7 DCP, did not completely break, due to the probable development of the in situ PLA‐g‐EVA compatibilizer among the present phases. Therefore, it is believed that a more homogeneous microstructure was obtained, as observed by SEM images, highlighted upon the DCP content increase. It was verified that the highest vinyl acetate content is of paramount importance for obtaining PLA/EVA blends with better compatibility as well as EVA1 being more susceptible to crosslinking using DCP, resulting in blends with greater toughness. [ABSTRACT FROM AUTHOR]

Polypropylene/Syagrus Cearensis fiber composites compatibilized with polypropylene‐graft‐maleic anhydride (PP‐g‐MA) and styrene(ethylene‐butylene)‐styrene copolymer (SEBS‐g‐MA) were successfully produced using a co‐rotating twin‐screw extruder followed by injection molding. The composites were characterized by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The mechanical properties were determined by Izod impact and tensile testing. Thermal properties were obtained by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). Heat deflection temperature (HDT) was determined to study the thermomechanical properties of the composites. XRD and DSC indicated the presence of two polypropylene polymorphs: α and β. The unmodified PP/Fiber composites showed an incompatible behavior, presenting low fiber/matrix interaction and poor interfacial adhesion. The poor compatibility led to low elongation at break and impact strength but high tensile strength. PP‐g‐MA coupling agent promoted some adhesion to the PP/fiber interfaces but not enough to improve the impact strength. The composites with PP‐g‐MA exhibited improved tensile modulus and strength. The enhanced PP/fiber interfacial interaction promoted by SEBS‐g‐MA generated a better interplay of mechanical properties, improving impact strength and elongation at break while preserving the elastic modulus and tensile strength. In general, the fibers enhanced the thermomechanical stability of PP, as evidenced by higher HDT values. [ABSTRACT FROM AUTHOR]

In this work, blends based on poly (lactic acid) (PLA)/acrylonitrile-butadiene-styrene (ABS) compatibilized with maleic anhydride-grafted (SEBS-g-MA) were prepared in a co-rotational twin-screw extruder by varying the concentrations of the compatibilizing agent. The influence of the compatibilizing agent on the morphology, mechanical, thermal, thermomechanical, and rheological properties of the prepared materials was analyzed. The effect of annealing on the properties of the blends was also investigated using injection-molded samples. The X-ray diffraction (XRD) results proved that the increments in crystallinity were an effect of annealing in the PLA/ABS/SEBS-g-MA blends, resonating at higher heat deflection temperatures (HDTs). The impact strength of the PLA/ABS blends compatibilized with 10 wt% SEBS-g-MA was significantly increased when compared to the PLA/ABS blends. However, the hardness and elastic modulus of the blends decreased when compared to neat PLA. The refined morphology shown in the scanning electron microscopy (SEM) analyses corroborated the improved impact strength promoted by SEBS-g-MA. The torque rheometer degradation study also supported the increased compatibility between SEBS-g-MA, PLA, and ABS. The TGA results show that the PLA/ABS and PLA/ABS/SEBS-g-MA blends are more thermally stable than the neat PLA polymer at higher temperatures. The results showed that the ideal composition is the heat-treated PLA/ABS/SEBS-g-MA (60/30/10 wt%), given the high impact strength and HDT results. The results of this work in terms of mechanical improvement with the use of compatibilizers and annealing suggest that the PLA/ABS/SEBS-g-MA system can be used in the production of 3D-printing filaments. [ABSTRACT FROM AUTHOR]

Nylon 6/acrylonitrile-butadiene-styrene nanocomposites were prepared by mixing in a molten state and injection molded for application in electromagnetic interference shielding and antistatic packaging. Multi-wall carbon nanotubes (MWCNT) and maleic anhydride-grafted ABS compatibilizer were incorporated to improve the electrical conductivity and mechanical performance. The nanocomposites were characterized by oscillatory rheology, Izod impact strength, tensile strength, thermogravimetry, current-voltage measurements, shielding against electromagnetic interference, and scanning electron microscopy. The rheological behavior evidenced a severe increase in complex viscosity and storage modulus, which suggests an electrical percolation phenomenon. Adding 1 to 5 phr MWCNT into the nanocomposites produced electrical conductivities between 1.22 × 10−6 S/cm and 6.61 × 10−5 S/cm. The results make them suitable for antistatic purposes. The nanocomposite with 5 phr MWCNT showed the highest electromagnetic shielding efficiency, with a peak of –10.5 dB at 9 GHz and a value around –8.2 dB between 11 and 12 GHz. This was possibly due to the higher electrical conductivity of the 5 phr MWCNT composition. In addition, the developed nanocomposites, regardless of MWCNT content, showed tenacious behavior at room temperature. The results reveal the possibility for tailoring the properties of insulating materials for application in electrical and electromagnetic shielding. Additionally, the good mechanical and thermal properties further widen the application range. [ABSTRACT FROM AUTHOR]

In this work, the copolymers ethylene-glycidyl methacrylate (E-GMA), ethylene methyl methacrylate-glycidyl methacrylate (EMA-GMA), and styrene-(ethylene-butylene)-styrene grafted with maleic anhydride (SEBS-g-MA) were used to compatibilize polystyrene (PS)/poly(caprolactone) (PCL) blends. The blends were processed in a co-rotating twin-screw extruder and injection molded. Samples were investigated by torque rheometry, capillary rheometry, impact strength, tensile strength, heat deflection temperature (HDT), dynamic-mechanical thermal analysis (DMTA), thermogravimetry (TG), and scanning electron microscopy (SEM). Torque rheometry indicated that glycidyl methacrylate functional groups and maleic anhydride groups interact with PCL. Capillary rheometry evidenced that at shear rates lower than 10,000 s−1, the PS/PCL/SEBS-g-MA blends presented the highest apparent viscosity among the blends. Such behavior was possibly due to the good interaction between SEBS-g-MA and the PS and PCL phases. Consequently, the properties of impact strength, elongation at break, tensile strength, and elastic modulus were improved by 30%, 109%, 33.8%, and 13.7%, respectively, compared with the non-compatibilized PS/PCL system. There was a reduction in the HDT of all blends compared with neat PS, given the elastomeric characteristics of PCL and compatibilizers. The DMTA results revealed two independent peaks in the blends (one around −53 °C concerning the PCL phase and another at 107 °C related to PS), confirming their immiscibility. The PS/PCL/SEBS-g-MA blends showed higher morphological stability, confirming their good mechanical properties. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]