Impregnação de filmes do compósito de policarbonato (PC) e sílica-gel (Si) com corante fotocrômico em fluido supercrítico

Autor: Nanci Pinheiro, Onélia Aparecida Andreo dos Santos, Fernanda de Almeida Fin de Lima
Rok vydání: 2010
Předmět:
Zdroj: Acta Scientiarum. Technology. 32
ISSN: 1807-8664
1806-2563
DOI: 10.4025/actascitechnol.v32i1.1999
Popis: The aim of this work was to study the impregnation of the photochromic dye Reversacol Graphit ® in composite films of polycarbonate (PC) and silica gel, with the purpose of finding applications in photochromic lenses. Pure PC films were also impregnated in the same conditions, to verify the effect of the silica-gel addition. The composites films were produced in Si:PC ratios of 1:40 and 1:80 (m m -1 ), using the casting method . For the impregnation of the dye Reversacol Graphit ® in the obtained films, the supercritical process was used due to its efficiency and benefits. The impregnation was made in the times of 15, 30, 45, 60, 90, 120, 150 and 180 minutes. The adopted temperature and pressure were 60oC and 120 bar, respectively. The amount of pigment impregnated in Si:PC films – 1:40 and 1:80 (m m -1 ) was 29 and 23% of dye mass per composite mass, respectively, and for pure PC film it was only 2.2% dye mass per composite mass. From the thermal analyses, it was verified that the composite films presented greater thermal stability. From the technique of electronic microscopy, it was observed that pure PC films and the composites Si:PC – 1:40 and 1:80 (m m -1 ) presented a smooth and homogeneous surface.
Databáze: OpenAIRE