Processing of sucrose to low density carbon foams

A novel process for preparation low density carbon foams from sucrose has been demonstrated. A resin prepared by heating aqueous acidic sucrose solution when heated in an open Teflon mould at 120 °C undergoes foaming and then setting in to a solid organic foam. The solid organic foam undergoes carbonization in air by dehydration at 250 °C under isothermal condition. Carbon foams thus obtained sintered at temperature in the range 600–1,400 °C showed density in the range 115–145 mg/cc and electrical conductivity in the range 1.5 × 10⁻⁵ to 0.2 ohm⁻¹ cm⁻¹, respectively. The carbon foams contain spherical cells of size in the range 450–850 μm and the cells are interconnected through circular or oval shape windows of size in the range 80–300 μm. The carbon foam samples sintered at 1,400 °C showed compressive strength of 0.89 MPa.