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In this work, PA6/EPDM-MA was added as an impact modifier for highperformance polypropylene (PP) production. PA6/EPDM-MA compounds were processed in an internal mixer, aiming at chemical reaction between maleic anhydride of EPDM-MA and the amine terminal groups of PA6. Afterward, PP/(PA6/EPDM-MA) blends were processed by extrusion and injection molding. Rheological properties were evaluated using torque rheometry; additionally, Fourier transform infrared spectroscopy, Molau test, impact and tensile strengths, Shore D hardness, thermal deflection temperature, X-ray diffraction, differential scanning calorimetry, thermogravimetry, water absorption, contact angle, and scanning electron microscopy tests were performed in injected specimens. PP/(PA6/EPDM-MA) with 70/(15/15)% displayed quite high increase in impact and elongation at break, with gains of 850% and 265%, compared to neat PP. There were no drastic losses in tensile strength, elastic modulus, and Shore D hardness, due to PA6 addition. A significant increase was seen in the thermal stability of PP/(PA6/EPDM-MA), corroborating the increase in structural stability seen in HDT. SEM images showed high interfacial adhesion between PP and PA6/EPDM-MA corroborating higher mechanical properties.Summing up, PA6/EPDM-MA premix acted as an efficient impact modifier for PP. Acquired data show that P6/EPDM-MA system was effective in developing high-performance PP with potential for application in the automotive and electronics industries.high-performance blends, PP/(PA6/EPDM-MA), reactive processing | INTRODUCTIONPolypropylene (PP) is one of the most common industrially applied polymers, mainly due to its low cost, low density, good thermal properties, excellent processability, and reasonable mechanical properties. [1][2][3] However, PP displays low impact strength, which limits its higher performance applications [4] ; hence, PP must be toughened to expand the range of its properties. [5] Toughness is a quite useful parameter that determines whether a given

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The practice of recycling over the years has been increasingly encouraged, with the aim being the manufacturing of materials that contribute to sustainable development. In light of this, the present work evaluated the potential of mixtures of polystyrene (PS)/recycled copolymer polypropylene (PPr), using styrene-(ethylene/butylene)-styrene (SEBS) as a compatibilizing agent. Initially, the mixtures were prepared in a co-rotational twin-screw extruder, and, afterwards, the extruded granules were molded by injection. The properties of torque rheometry, impact strength, tensile properties, differential scanning calorimetry (DSC), heat deflection temperature (HDT), and scanning electron microscopy (SEM) were evaluated. The formulation PS/PPr/SEBS (70/20/10 %wt.) demonstrated an increase in viscosity, corroborating with an increase of 123% and 227% in the elongation at break and impact strength, respectively, compared to neat PS. Though the elastic modulus and tensile strength suffered losses, the reduction was not drastic. Furthermore, the addition of a semi-crystalline recycled material in the amorphous matrix (PS) contributed to an increase in thermomechanical strength, as seen in the HDT. The morphology revealed that SEBS is effective in making PS/PPr mixtures compatible because the dispersed phase is well adhered to the PS matrix and promotes greater morphological stability. Thus, it is possible to add value to discarded material and reduce the costs of the final product, which can reduce pollution.

Motivated by environment preservation, the increased use of eco-friendly materials such as biodegradable polymers and biopolymers has raised the interest of researchers and the polymer industry. In this approach, this work aimed to produce bioblends using poly (lactic acid) (PLA) and high-density biopolyethylene (BioPE); due to the low compatibility between these polymers, this work evaluated the additional influence of the compatibilizing agents: poly (ethylene octene) and ethylene elastomer grafted with glycidyl methacrylate (POE-g-GMA and EE-g-GMA, respectively), polyethylene grafted with maleic anhydride (PE-g-MA), polyethylene grafted with acrylic acid (PE-g-AA) and the block copolymer styrene (ethylene-butylene)-styrene grafted with maleic anhydride (SEBS-g-MA) to the thermal, mechanical, thermomechanical, wettability and morphological properties of PLA/BioPE. Upon the compatibilizing agents’ addition, there was an increase in the degree of crystallinity observed by DSC (2.3–7.6% related to PLA), in the thermal stability as verified by TG (6–15 °C for TD10%, 6–11 °C TD50% and 112–121 °C for TD99.9% compared to PLA) and in the mechanical properties such as elongation at break (with more expressive values for the addition of POE-g-GMA and SEBS-g-MA, 9 and 10%, respectively), tensile strength (6–19% increase compared to PLA/BioPE bioblend) and a significant increase in impact strength, with evidence of plastic deformation as observed through SEM, promoted by the PLA/ BioPE phases improvement. Based on the gathered data, the added compatibilizers provided higher performing PLA/BioPE. The POE-g-GMA compatibilizer was considered to provide the best properties in relation to the PLA/BioPE bioblend, as well as the PLA matrix, mainly in relation to impact strength, with an increase of approximately 133 and 100% in relation to PLA and PLA/BioPE bioblend, respectively. Therefore, new ecological materials can be manufactured, aiming at benefits for the environment and society, contributing to sustainable development and stimulating the consumption of eco-products.

RESUMOO reômetro de torque é um equipamento que reproduz em escala laboratorial o processamento de polímeros. Neste equipamento, a velocidade de rotação dos rotores, temperatura e tempo de processamento são parâme-tros predeterminados e impostos ao sistema investigado; avalia-se o torque necessário para a fusão, mistura e homogeneização da amostra. Através do gráfico do torque em função do tempo e do gráfico da temperatura em função do tempo de processamento, cujos valores estão relacionados com as propriedades reológicas, estrutura e massa molar das amostras, é possível obter informações sobre o comportamento dos polímeros em fluxo, ou seja, durante o processamento. Neste trabalho, foi investigado o efeito do polietileno graftizado com ácido acrílico (PEgAA) e do polietileno graftizado com anidrido maléico (PEgMA) no biopolietileno (Bio-PE) e no poli(ε-caprolactona) (PCL) por reometria de torque. Foi verificado que o PEgAA e o PEgMA promoveram aumento no torque dos sistemas Bio-PE/PEgAA, Bio-PE/PEgMA, PCL/PEgAA e PCL/PEgMA, possivelmente resultante de interações e/ou reações químicas ocorridas nesses sistemas poliméricos. Espectros de FTIR evidenciaram possíveis interações e/ou reações químicas entre os grupos funcionais dos políme-ros grafitizados e o Bio-PE e o PCL. Valores de torque mais altos foram observados nos sistemas com parâ-metros de solubilidade (δ) mais próximos, corroborando com os cálculos propostos por Hansen. Palavras-chave:Bio-PE, PCL, PEgAA, PEgMA, reometria de torque, parâmetro de solubilidade. ABSTRACTThe torque rheometer is equipment that enables to simulate the polymer processing in a laboratory scale. A set of parameters, i.e., rotor speed, temperature and processing time are predefined and imposed to the compounds under analysis. The necessary torque for melting and mixing the compound is measured. Through the plots of torque as a function of time and temperature, which are linked to the rheological properties, microstructure and molar weight of the samples, it is possible to acquire information regarding the flow behavior of polymers, meaning during processing. In this work, the effect of acrylic acid-grafted polyethylene (PEgAA) and maleic anhydride-grafted polyethylene (PEgMA) in bio-polyethylene (Bio-PE) and in poly(ε-caprolactone) (PCL) was performed by torque rheometry. PEgAA and PEgMA increased the torque rheometry values of the polymeric systems under investigation, i.e, Bio-PE/PEgAA, Bio-PE/PEgMA, PCL/PEgAA and PCL/PEgMA, possibly due to chemical interaction and/or reactions occurred during the processing. FTIR spectra presented possible interactions and/or chemical reactions between the functional groups of grafted polymers and Bio-PE and PCL. Higher torques were observed for the systems with similar solubility parameters agreeing with the mathematical calculations provided by Hansen.

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