resumo
The influence of myristyl alcohol (CH3(CH2)13OH), cetyl alcohol (CH3(CH2)15OH) and behenyl alcohol (CH3(CH2)21OH) on the structure, morphology, size and surface properties of calcium carbonate (CaCO3) has been investigated. Changes in the nature of the washing solvent, in the CnOH/Ca2+ and CO32-/Ca2+ molar ratios and in temperature have been also evaluated. The sole polymorph produced was rhombohedral calcite. At room temperature, while microspheres composed of submicrocubes were produced at a high molar ratio CO32-/Ca2+ and low CH3(CH2)15OH concentration, a stoichiometric molar ratio CO32-/Ca2+ and high CH3(CH2)15OH concentration induced the formation of microcubes and microboxes. In the presence of this alkanol (12 % molar) a significant enhancement of the water contact angle (ca. 40 degrees) resulted in a sample obtained with a stoichiometric CO32-/Ca2+ ratio. These results emphasize the key role played by the three non-ionic surfactants in the formation of materials with variable crystal shape and wettability and thus technological interest for a range of applications.
palavras-chave
IONIC LIQUID; GROWTH; CRYSTALLIZATION; MORPHOLOGY; ALCOHOL; ETHANOL; WATER; NANOPARTICLES; ARAGONITE; VATERITE
categoria
Crystallography
autores
Fernandes, M; Paz, FAA; Mano, JF; Bermudez, VD
nossos autores
Filipe Alexandre Almeida Paz
Investigador PrincipalProjectos
Bio-inspired deposition of a biomineral on biopolymers and on biopolymer/siloxane hybrids for biomedical applications (PTDC/CTM-BPC/112774/2009)
Centre for Research in Ceramics and Composite Materials - CICECO (LA0011: 2013-2014) (PEst-C/CTM/LA0011/2013)
Rational design of hybrid organic-inorganic interfaces: the next step towards advanced functional materials (HINT)
agradecimentos
This work was financially supported by Fundacao para a Ciencia e a Tecnologia (FCT) (contracts PTDC/CTM-BPC/112774/2009, Pest-C/CTM/LA0011/2013, Pest-OE/QUI/UI0616/2014, PTDC/FIS/115048/2009 and PTDC/CTM-BIO/1814/2012) and COST Action MP1202