JULIO HARADA
3 resultados
Resultados de Busca
Agora exibindo 1 - 3 de 3
Artigo IPEN-doc 30269 Evaluation of graphene incorporation for mechanical properties of polypropylene composites2023 - HARADA, JULIO; MARCONDES, CLAUDIO A.; PEREIRA, MARIA da C.C.; SILVA, LEONARDO G.A.Graphene nanoparticles (GnP) was selected as an alternative reinforcement, nanofillers, to enhance the mechanical properties of polypropylene (PP-homo and PP-copolymer) and using compatibilizer, maleic anhydride graphitized with polypropylene (PP-g-MA) in a twin-screw extruder. The effect of GnP loading and the use of the PP-g- MA compatibilizer were studied. The influence on the mechanical properties of tensile strength, elongation, IZOD impact strength, and melting temperature in PP-homo and PP-copolymer were investigated and compared. Their improvement was observed up to a certain amount, depending on whether it is a homopolymer or copolymer. The PP copolymer has a greater affinity with graphene and the compatibilizer due to the elastomeric comonomer present in the copolymer.Artigo IPEN-doc 28339 Influence of electron beam irradiation on the mechanical properties of pbat/pla polymeric blend2021 - MUNHOZ, PEDRO M.; NASCIMENTO, FERNANDO C.; SILVA, LEONARDO G. de A. e; HARADA, JULIO; CALVO, WILSON A.P.The aim of this research was to evaluate the changes in the mechanical properties of poly(butylene adipate co-terephthalate)/poly(lactic acid) (PBAT/PLA) polymeric blend after the radiation process at different radiation doses. The irradiation was performed in an electron beam accelerator, with 1.5 MeV of energy and 25 mA electric current. The samples were irradiated with doses of 5, 10, 15, 25, 50, 65 and 80 kGy. Both irradiated and non-irradiated samples were characterized by Izod pendulum impact resistance and tensile strength at rupture. The results showed an increase of 44% in relation to Izod impact resistance at a dose of 65 kGy. However, the module of elasticity decreased 56% and tensile strength at rupture decreased 55% at the same radiation dose. In relation to elongation, significant alterations caused by electron beam irradiation was not observed. Therefore, it can be concluded that irradiated blends could be used to make environmentally friendly products, which could absorb impact energy.Artigo IPEN-doc 24873 Investigação das propriedades dos compósitos formados por resina uretânica elastomérica e vermiculita processada2017 - OLIVEIRA, JOSE M.D.; COELHO, ANTONIO C.V.; BARBERATO, FERNANDA; HARADA, JULIO; SILVA, LEONARDO G.A.; CABRAL NETO, ABNERNa tentativa de melhorar a tensão de ruptura da resina uretânica elastomérica (TPU), foi estudada adição de vermiculita processada a esta resina. Os compósitos resultantes foram avaliados em microscopia eletrônica de varredura (MEV), Calorimetria Exploratória Diferencial (DSC), e análise termogravimétrica (TGA). Os resultados de tensão de ruptura obtidos para os compósitos formados pela resina uretânica elastomérica e vermiculita processada apontam para a necessidade estudos complementares de compatibilização e de processamento.