INFLUENCE OF MIXING SEQUENCE ON THE PROPERTIES OF BLENDS OF PS/SBRr COMPATIBILIZED WITH SBS

Blends of polystyrene (PS) containing styrene-butadiene rubber (SBRr) wastes were prepared using 5% the styrenebutadiene-styrene compatibilizer agent (SBS). The blends were initially processed in a corrotational twin screw extruder and subsequently, the extruded pellets were molded by injection. The blends were mechanically characterized (Impact and Bending) and morphologically (SEM). The main objective was to analyze the influence of mixing sequence on the morphology and mechanical properties of these blends. The results showed that the impact strength increased significantly, while losses in the resistance to flexure property occurred in comparison to the polymer matrix. When the SBS and PS were mixed together in a first extrusion step, prior to incorporation of SBRr in a second extrusion step, an optimization of the impact strength increased by 302% in relation to polystyrene matrix. These results show a good perspective of application of these industrial wastes (SBRr), since they can add value to a material that would otherwise be discarded

Development of Polymer Blends in order to Toughening of Polymers: A review

Polymers are materials of large use in the various sectors of the world economy. The use of polymeric materials in daily life, instead of the classic materials has increased in recent decades. However, for certain structural applications polymers need to get tougher. One of the principal toughening techniques based on physical mixture of two or more components, forming the so-called polymer blends. The addition of rubber or not vulcanized in polymer compositions is reported in the literature as a means of generating mixtures of easy processing, and economically advantageous to increase the toughness of the thermoplastic matrix of interest. Moreover, it can be an alternative for the recycling of waste tires and footwear coming from industries, as well reduce harmful effects on the environment. Therefore, the present study aims to present a review of the definitions, benefits, thermodynamic fundamentals and toughening polymers.</p

O Protagonismo Infantojuvenil nos Processos Educomunicativos

Neste volume “O protagonismo infantojuvenil nos processos educomunicativos”, reunimos 53 artigos que transitam sobre a temática do protagonismo infantojuvenil em diversas experiências e processos educomunicativos e para facilitar sua leitura e busca por temas de seu interesse, eles estão organizados em 8 capítulos que abordam a educomunicação a partir do fazer das crianças e da apropriação da produção midiática.&nbsp;Expressão artística, rádio, vídeo, jornalismo, cultura digital, redes sociais entre outros são os temas abordados pelos autores destes trabalhos. convidamos o leitor&nbsp;a mergulhar nesta jornada educomunicativa, vivendo e revivendo junto conosco essas experiências vividas por outros, refletindo em cada texto sobre como estamos, como evoluímos e como seguimos os passos daqueles que com sua ousadia, amor e luta elaboraram os fundamentos da educomunicação