Banca de QUALIFICAÇÃO: LAURENICE MARTINS PEREIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : LAURENICE MARTINS PEREIRA
DATA : 31/03/2017
HORA: 08:30
LOCAL: SALA 3 - ECT
TÍTULO:

Influence of the addition of styrenic polymers and copolymers on the properties of blends with poly (methyl methacrylate)


PALAVRAS-CHAVES:

Polymer blends, poly (methyl methacrylate), polystyrene, poly (styrene-co-acrylonitrile) and poly (acrylonitrile-co-styrene-co-butadiene)


PÁGINAS: 126
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
ESPECIALIDADE: Polímeros, Aplicações
RESUMO:
The development of new materials to meet the needs of technological advances is a challenge faced by researchers from around the world. With regard to polymeric materials, strategies such as blends polymer is a promising alternative to meet the demand for materials with properties different from those found in conventional polymers. The aim of this work is to evaluate the influence of the addition of styrene, acrylonitrile and butadiene monomers on the mechanical properties when the dispersed phases of polystyrene (PS), poly (styrene-co-acrylonitrile) (SAN) and polyacrylonitrile- Styrene-butadiene) (ABS) were added in the matrix of common poly (methyl methacrylate) (PMMAc) and poly (methyl methacrylate) elastomeric (PMMAel). In order to improve the properties of these materials, the poly (styrene-methyl methacrylate) (SMMA) compatibilizing agent was added. The blends were produced by means of a twin screw extruder and then injection molded. The characterization was carried out using melt index (MFI), capillary rheometry, mechanical tensile test, heat distortion temperature (HDT), softening temperature vicat, Izod impact strength and Shore D hardness. Melt flow index results corroborated the results of capillary rheometry of the pure polymers, since they presented the same viscosity sequence. And the melt flow index of PMMA blends increased with the introduction of styrene polymers. The tensile tests showed that the addition of SAN improved the tensile strength and modulus of elasticity of the blends compared to addition of PS and ABS. In the elongation at break results, the PMMAc/ABS blends showed greater elongation, probably due to the presence of the butadiene domains, and in the blends with PMMAel all presented synergism. In the results of Izod impact resistance the blends with PMMAel matrix presented better results, precisely the blends of PMMAel/SAN and PMMAel/ABS. In the HDT results it was observed that the addition of the 3 dispersed phases increased the thermal distortion resistance of the blends when added to PMMAc and PMMAel. At the Vicat softening temperature, the pure polymer with the highest softening temperature was the SAN, and in the blends the addition of 30% by mass of the dispersed phase favored the increase of the temperature for the blends with SAN and ABS. The addition of styrene polymers in the PMMA influenced less on the Vicat result than on the HDT results, as the temperature increases were higher in the HDT results. In the results of Shore D hardness all the blends polymer presented synergism for this property. It also observed that there was no linear increase or reduction of hardness, with the increase of the percentages of the dispersed phases. The compatibilized blends for all the tests did not show significant changes in the results when compared to the non compatibilized blends. It was concluded that the blends with SAN and ABS presented the best results for the studied properties, indicating that acrylonitrile and butadiene present had an influence on the results.

MEMBROS DA BANCA:
Presidente - 1639676 - EDSON NORIYUKI ITO
Interno - 1755267 - MARIA CAROLINA BURGOS COSTA DO NASCIMENTO
Externo ao Programa - 2254759 - AMANDA MELISSA DAMIAO LEITE
Notícia cadastrada em: 29/03/2017 10:17
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