https://repositorio.ufba.br/handle/ri/8297
Tipo: | Artigo de Periódico |
Título: | Precipitation of LDPE-EPDM and LDPE-EVA mixtures from ternary solutions |
Título(s) alternativo(s): | European Polymer Journal |
Autor(es): | Esperidião, Maria Cecília Azevedo Galembeck, Fernando |
Autor(es): | Esperidião, Maria Cecília Azevedo Galembeck, Fernando |
Abstract: | The fast precipitation of mixtures of low-density polyethylene (LDPE) with ethylene-propylene-diene terpolymer (EPDM) and ethylene-vinyl acetate (EVA) copolymer, from xylene solutions by cooling, leads to fractionation of the mixtures. LDPE/EPDM mixtures are also fractionated by cooling followed by nonsolvent addition. Studies by density-gradient centrifugation, IR spectroscopy, optical microscopy and wide-angle X-ray diffraction showed that the composition and morphology of LDPE/EPDM fractions depend on the precipitation procedures. LDPE crystalline structure in each fraction is different, changes with the time and depends on EPDM content. EVA fractions that co-precipitate are richer in -CH2-CH2-units. LDPE/EPDM and LDPE/EVA precipitates showed chemical composition distribution and morphological characteristics different among themselves. Larger aggregates were observed in the LDPE/EPDM precipitates. These differences were attributed to differences in the phase diagrams and in the phase separation mechanisms. |
URI: | http://www.repositorio.ufba.br/ri/handle/ri/8297 |
Data do documento: | 1997 |
Aparece nas coleções: | Artigo Publicado em Periódico (Química) |
Arquivo | Descrição | Tamanho | Formato | |
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ESPERIDIão.pdf Restricted Access | 867,52 kB | Adobe PDF | Visualizar/Abrir Solicitar uma cópia |
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