Estudo da interação de blenda elastomérica SBR-BR com cargas particuladas na formação de compósitos

• Ano de defesa: 2003
• Autor(a) principal: Venter, Sandro Aurélio de Souza
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual de Maringá; Brasil; Programa de Pós-Graduação em Química; UEM; Maringá, PR; Departamento de Química
• Palavras-chave em Português: Pneu; Elastômeros; Sílica; Negro de fumo; Análises térmicas; Degradação.; Ciências Exatas e da Terra; Química
• Link de acesso: http://repositorio.uem.br:8080/jspui/handle/1/3883

The use of elastomeric materials without filler has limited applications due great susceptibility the polymers to change temperatures. In the current days carbon black is the most used filler to reinforce elastomers in the tyre industry. Silica has showed an interesting reinforced filler due to produce tyre with smaller adherence with the tracks, reducing the fuel consumption and resulting lower emission of poluent gases to atmosphere. In this work the filler-polymer interaction was study with carbon black, silica and carbon black-silica association as filler and SBR-BR blend as elastomeric material. Extraction process with toluene shows higher gel content polymer-filler to composite SBR-BR/20 phr SiO2 (BdR = 38,4%) characterizing the best polymer-filler interadions. This composite shows the lower abrasion index in the mecanic tests too. The filler-filler interactions that take the formation of agglomerates werw monitored by EDS. EDS analysis of SBR-BR/silica composites showed that 30 phr one happens agglomerations silica-silica, not observed in lower concentractions compared to composite with 30 phr silica. These composites presented high abrasion index. Thermogravimetric studies of composites SBR-BR/filler showed that high silica filled ones present lower activation energy and has degradation process started at low temperatures, evidencing a less effective polymer-filler interaction. Composites samples SBR-BR filled with carbon-black-silica associations in the concentractions 40-25e 50-15 phr, present the same BdR values. The activation energy to high concentraction of silica gel showed a decrease in this parameter indicating silica agglomerations in this case, that wasn?t observed in gel of composite filled with 15 phr silica. The pirolysis products of the polybutadiene, monitored by mass spectrometer, showed the produce of fragments with 4 and 5 carbons. To gels filled with different carbon black-silica associations, these fragments have the same number of carbons with high degree of insaturactions, that can be indicating resonance in these fragments. It was verified from IR spectra main peacks at 2900, 1640, 1540cm-1 and 1000 to 900cm-1 range, for the sample not pirolysed. The pirolysis products show the IR spectra with bands in the sane range, with the difference of CO2 bands.