Prof. Lennart Bergstrom - Assembly of nanoparticles and nanocellulose‐based hybrids
Date: 8 October 2014 Time: 15:00 - 16:00
Nanocellulose is a renewable nanomaterial with outstanding properties that is attracting a
rapidly growing scientific and technological interest with applications such as composites,
barrier films, scaffold materials, and multifunctional foams and aerogels. Nanocellulose
combines a versatile chemical‐modification capacity, low thermal expansion, and excellent
mechanical properties with a high surface area.
In this presentation, we will show how nanoparticles and nanocellulose can be processed, to
produce composite films and foams with useful properties. Assembly of iron oxide nanocrystals
into ordered arrays or superlattices with both translational and or ientational order
(mesocrystals) is demonstrated and discussed. We discuss the liquid crystal ordering
phenomena with CNC suspensions and compare with the corresponding self‐assembly
processes of other liquid crystal‐forming rod‐like nanoparticles.
We will demonstrate how the microstructure and magnetic, mechanical, and optical properties
of various inorganic‐nanocellulose hybrids can be tailored by controlling the foaming and
assembly of nanocellulose and how the properties can be tailored by nucleation and growth of
inorganic nanoparticles onto the nanocellulose surfaces. Examples include hybrids based on
nanocellulose crystals and amorphous calcium carbonate results in transparent and hard hybrid
coatings and hybrids of cellulose nanofibrils and titania nanoparticles that result in transparent
and flexible free‐standing films with a hardness comparable to concrete. Finally, we will
demonstrate how freeze‐cast foams based on cellulose nanofibres and clays can yield superinsulating,
fire‐retardant and strong ultralight cellular materials.
|Location:||David Sizer Lecture Theatre, Bancroft Building|