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Desenvolvimento de espumas de um componente (OCF) "verdes" com resistência melhorada ao fogo e à chama
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Resumo(s)
Desenvolveram-se espumas de poliuretano de um componente (OCF) com resistência melhorada ao fogo e à chama, (classificadas como B2 de acordo com a norma DIN 4102-parte 1), para serem eventualmente aplicadas em isolamento térmico.
Foram estudados diferentes retardantes de chama. Obtiveram-se espumas com classificação B2 de acordo com a norma anteriormente referida, concluindo-se que o sucesso da resistência à chama está relacionado com a combinação de mecanismos de combustão e propagação de chama, em fase gasosa e em fase condensada.
Verificou-se também que as espumas otimizadas apresentaram diferente comportamento térmico, causado por diferenças de mobilidade segmentar na região amorfa do polímero.
A formulação das espumas produzidas foi continuamente otimizada, de forma a poderem ser utilizadas para a aplicação pretendida. Para proceder a esta otimização recorreu-se à determinação de algumas propriedades das espumas, entre elas o aspeto visual e a densidade. Foram também estimados o caudal de saída das espumas do interior das latas de aerossol e foram realizados testes de resistência à chama de acordo com a norma DIN 4102.
As formulações otimizadas foram submetidas a análises de HPLC, verificando-se que possuem um conteúdo de MDI monomérico livre inferior a 1%, cumprindo a lei europeia de segurança de produtos químicos e poderem ser comercializadas.
One component polyurethane foams (OCF) with improved resistance to fire and flame, were developed (classified as B2 according to standard DIN 4102-part 1) to be eventually applied in thermal insulation. Different flame retardants have been studied. Several formulations achieved the B2 rating according to DIN4102 standard. The success of flame resistance was concluded, to be related with the combination of mechanisms of combustion and flame propagation both in gas phase and condensed phase. It was also found that the optimum foams had different thermal behavior caused by differences in the segmental mobility of the amorphous region of the polymer. The obtained foam formulations were continuously optimized, in order to make them operational for the intended purpose. In order to optimize these foam formulations, some properties of the foams were studied: visual appearance and density. It was also studied the output from the can of the foam formulations. The fire resistances tests were evaluated in accordance with DIN 4102. The optimized formulations were analyzed by HPLC, confirming that the optimized formulations have a free monomeric MDI content of less than 1%, complying with European safety law of chemicals and thus can be introduced in the market.
One component polyurethane foams (OCF) with improved resistance to fire and flame, were developed (classified as B2 according to standard DIN 4102-part 1) to be eventually applied in thermal insulation. Different flame retardants have been studied. Several formulations achieved the B2 rating according to DIN4102 standard. The success of flame resistance was concluded, to be related with the combination of mechanisms of combustion and flame propagation both in gas phase and condensed phase. It was also found that the optimum foams had different thermal behavior caused by differences in the segmental mobility of the amorphous region of the polymer. The obtained foam formulations were continuously optimized, in order to make them operational for the intended purpose. In order to optimize these foam formulations, some properties of the foams were studied: visual appearance and density. It was also studied the output from the can of the foam formulations. The fire resistances tests were evaluated in accordance with DIN 4102. The optimized formulations were analyzed by HPLC, confirming that the optimized formulations have a free monomeric MDI content of less than 1%, complying with European safety law of chemicals and thus can be introduced in the market.
Descrição
Tese de mestrado em Química Tecnológica, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2013
Palavras-chave
Poliuretano Espuma de um componente Retardante de chama DIN 4102 Isolamento térmico Teses de mestrado - 2013