Abstract
The mechanism of silica particle formation in monomer microemulsions is studied using dynamic light scattering (DLS), atomic force microscopy, small-angle X-ray scattering (SAXS), and conductivity measurements. The hydrolysis of tetraethylorthosilicate (TEOS) in methylmethacrylate (MMA) microemulsions (MMA = methylmethacrylate) is compared with the formation of SiO2 particles in heptane microemulsions. Stable microemulsions without cosurfactant were found for MMA, the nonionic surfactant Marlophen NP10, and aqueous ammonia (0.75 wt%). In the one-phase region of the ternary phase diagram, the water/surfactant ratio (R w) could be varied from 6 to 18. The DLS and SAXS measurements show that reverse micelles form in these water-in-oil (w/o) microemulsions. The minimum water-to-surfactant molar ratio required for micelle formation was determined. Particle formation is achieved from the base-catalyzed hydrolysis of TEOS. According to atomic force microscopy measurements of particles isolated from the emulsion, the particle size can be effectively tailored in between 20 and 60 nm by varying R w from 2–6 in heptane w/o microemulsions. For MMA-based microemulsions, the particle diameter ranges from 25 to 50 nm, but the polydispersity is higher. Tailoring of the particle size is not achieved with R w, but adjusting the particle growth period produces particles between 10 and 70 nm.
Similar content being viewed by others
References
Grasset F, Marchand R, Marie AM, Fauchadour, D, Fajardie FJ (2006) Colloid Interface Sci 299:726
Boutonnet M, Kizling J, Touroude R, Maire G, Stenius P (1991) Catal Letters 9:347
Boutonnet Kizling M, Bigey C, Touroude R (1996) Appl Catal A 135:L13
Boutonnet Kizling M, Regali F (1998) Stud Surf Sci Catal 118:495
Fang JY, Wang J, Ng SC, Chew CH, Gan LM (1997) Nanostruct Mater 8:499
Althues H, Kaskel S (2002) Langmuir 18:7428
Texter J (2001) Reactions and synthesis in surfactant systems. Marcel Dekker, New York
Kumar P, Mittal KL (1999) Handbook of microemulsion science and technology. Marcel Dekker, New York
Pillai V, Shah DOJ (1996) Magn Magn Mater 163:243
Lopez Perez JA, Lopez Quintela MA, Mira J, Rivas J, Charles SWJ (1997) Phys Chem B 101:8045
Lopez-Quintela MA, Quiben-Solla J, Rivas J (1997) Surf Sci Series 66:247
Mira J, Lopez-Perez JA, Lopez-Quintela MA, Rivas J (1997) Mater Sci Forum 235–238:297
Tojo C, Blanco MC, Lopez-Quintela MA (1998) Synthesis of nanoparticles in microemulsions: a comparisons study between experimental and simulation results. In Proceedings of the International Workshop on Non-Crystalline Solids, Santiago de Compostela, vol 5, World Scientific, Singapore, pp 451–456
Li Y, Park CW (1999) Langmuir 15:952
Lopez-Quintela MA, Rivas J, Blanco MC, Tojo C (2003) Nanoscale Mater 135
Palkovits R, Althues H, Rumplecker A, Tesche B, Dreier A, Holle U, Fink G, Cheng CH, Shantz DF, Kaskel S (2005) Langmuir 21:6048
Chang C-L, Fogler HS (1996) AIChE Journal 42:3153
Osseo-Asare K (2000) Surf Sci Series 92:147
Chang C-L, Fogler HS (1997) Langmuir 13:3295
Eicke HF, Borkovec M, Das-Gupta BJ (1989) Phys Chem 93:314
Velazquez MM, Valero M, Ortega FJ (2001) Phys Chem B 105:10163
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Scholz, S., Althues, H. & Kaskel, S. Growth of silica nanoparticles in methylmethacrylate-based water-in-oil microemulsions. Colloid Polym Sci 285, 1645–1653 (2007). https://doi.org/10.1007/s00396-007-1736-3
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00396-007-1736-3