Growth and Disappearance of Nanobubbles during the Foaming of Polycarbonate

Autor:	Motohisa Kato, Tsuneo Chiba, Hiromu Saito, Yoshihito Fukasawa, Takashi Inoue
Rok vydání:	2008
Předmět:	Coalescence (physics) Ostwald ripening Materials science Number density Micrometer scale Polymers and Plastics Nanotechnology Field emission microscopy Nanopore symbols.namesake Chemical engineering visual_art Materials Chemistry visual_art.visual_art_medium symbols Polycarbonate
Zdroj:	Polymer Journal. 40:339-342
ISSN:	1349-0540 0032-3896
DOI:	10.1295/polymj.pj2007138
Popis:	We investigated the structural development of bubbles during the foaming of polycarbonate under carbon dioxide (CO2) by using a field emission scanning electron microscope (FE-SEM). Numerous CO2 nanopores having a size of around 50 nm were obtained by rapidly cooling the nanobubbles. At an early stage of the foaming, the size and number density of the nanobubbles increased over time. However, the number density of the bubbles later decreased and only a small number of nanobubbles grew to a larger size of micrometer scale, suggesting that most of the initially formed nanobubbles do not grow but disappear during the foaming. The disappearance of the nanobubbles might be attributed to the coalescence of neighboring nanobubbles and Ostwald ripening in which large bubbles grow at the expense of the small nanobubbles.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::bb55aeb8aecd048403fb11b63062ebe7 https://doi.org/10.1295/polymj.pj2007138 Zobrazit plný text záznamu