Abstract
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.
Highlights
A combinação de materiais conhecidos, tais como metais, cerâmicas e polímeros, promove contínua geração de novos produtos com melhores propriedades
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
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
Summary
Os reagentes utilizados neste estudo foram: policarbonato (PC-GE123R), com Mw= 120.000 g. Os filmes foram obtidos pela técnica casting, que consiste na evaporação do solvente, à temperatura ambiente, de uma fina camada da solução polimérica adicionada em uma placa de vidro lisa e adequadamente limpa. Os filmes de PC puro e Si:PC (1:40) e (1:80) m m-1 foram devidamente cortados e pesados para obtenção de massas aproximadamente iguais. Para cada tempo de impregnação, era inserido um filme na célula de tingimento, juntamente com o corante Reversacol Graphit® em pó, devidamente pesado. O corante ficava na parte inferior da célula de tingimento em um suporte poroso, de forma que, ao entrar em contato com o fluido supercrítico, ele passava para a região de distribuição de fluido e, após, permanecia em equilíbrio estático com o filme polimérico (SANTOS et al, 2001). Esquema do tingimento dos filmes com corante fotocrômico e detalhe do suporte poroso
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
