SciELO - Scientific Electronic Library Online

 
vol.14 número2Comportamento balístico de compósito de polietileno de altíssimo peso molecular: efeito da radiação gamaSíntese de um poli (ácido âmico) para aplicação como interfase em compósitos termoplásticos de alto desempenho índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Journal

Artigo

Indicadores

Links relacionados

Compartilhar


Polímeros

versão impressa ISSN 0104-1428versão On-line ISSN 1678-5169

Resumo

LENZI, Marcelo K.; LIMA, Enrique L.  e  PINTO, José Carlos. Modeling styrene simultaneous suspension and emulsion polymerization systems. Polímeros [online]. 2004, vol.14, n.2, pp.112-121. ISSN 1678-5169.  https://doi.org/10.1590/S0104-14282004000200015.

Although both emulsion and suspension polymerization processes are performed in heterogeneous media, each process presents its own typical characteristics, such as the particle size distribution, molecular weight distribution, polymer particle nucleation rates, rates of polymerization, and so on. In this work styrene polymerizations are carried out in suspension and emulsion processes simultaneously. The initial reactor charge resembles the recipe of standard styrene suspension polymerizations, while emulsion polymerization constituents are added during the batch. The influence of the moment when emulsion feed is started on the course of the polymerization and the effects on the polymer properties are analyzed. A mathematical model is developed to describe the behavior of the system. Simulation data obtained with the proposed model are in good agreement with experimental conversion, average molecular weight and molecular weight distribution data. It was observed that the polymer particle morphology and the average molecular weight change very significantly with the emulsion feed time and that such changes can lead to bimodal molecular weight distributions. Core-shell polymer particles were obtained, with the core being formed by polymer particles from the suspension polymerization process and the shell formed by polymer particles from the emulsion one.

Palavras-chave : Modeling; core-shell; simultaneous polymerization; semi-batch.

        · resumo em Português     · texto em Português     · Português ( pdf )

 

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons