Start
Jan 13, 2011 - 16:00
End
Jan 13, 2011 - 17:30
Venue
Creativity hall (Room 118) Chemical Eng.
Event Type
Speaker
Dr. Guruswamy Kumaraswamy Scientist Complex Fluids and Polymer Engineering Polymer Science and Engineering National Chemical Laboratory Pune.
Title
Making and assembling materials in surfactant hexagonal phases
Abstract: I will describe our recent work on polymerization and assembly of particles in surfactant hexagonal mesophases. We have demonstrated that synthesis of condensation polymers in a hexagonal mesophase results in the formation of rod-like colloidal objects. As the monomer polymerizes it swells the hexagonal phase and as the molecular weight increases it phase separates. This phase separated object is assembled into a hombohedral object and finally into a rod-like object by matrix mediated nteractions. I will also discuss assembly of particles in the hexagonal esophase. We show that the size of the nanoparticulate inclusion d in surfactant mesophase characterized by size a determines particle rganization in the mesophase. Small particles viz.d < a are templated y the mesophase while for d ~ a there is a coexistence between a ispersed particle phase and string like particle aggregates. For d > a the particles organize into networks of string-like aggregates. This behaviour is generic independent of the particle surface chemistry. We show the formation of networks of inorganic oxides metals proteins and polymer hydrogels in hexagonal mesophases. I will describe our use of this strategy to generate free standing macroporous materials.Bio-sketch: Dr. Guruswamy Kumaraswamy is a scientist at the National Chemical Laboratory Pune India where his group investigates soft complex materials such as polymers surfactants and colloids. Dr. Guruswamy received his B. Tech. from IITB Mumbai in 1994; his M.S. (1996) and Ph.D. (2000) from the California Institute of Technology USA (all degrees in Chemical Engineering). He spent a year as a VW Postdoctoral fellow at the Max Planck Institute for Colloids and Interfaces Germany before joining NCL in 2001. In addition to his science Dr. Guruswamy is passionate about science outreach to school students (see http://www.excitingscience.org)