Aerogels, emulsions, and composites: Controlling structure with organic sol-gel chemistry

Conference · Wed Apr 01 04:00:00 EST 1992

OSTI ID:7030589

Pekala, R W; Alviso, C T; Hulsey, S S; Kong, F M

The sol-gel polymerization of resorcinol with formaldehyde is a proven synthetic route for the formation of organic aerogels. These materials can also be pyrolyzed in an inert atmosphere to form vitreous carbon aerogels. Both resorcinol-formaldehyde and carbon aerogels are characterized by high porosity (50--98%), ultrafine cell/pore sizes (< 100 mn), high surface area (400--1000 m{sup 2}/g), and a solid matrix composed of interconnected colloidal-like particles or fibrous chains with characteristic diameters of 10 nm. While this nanostructure and the low Z (atomic number) composition are responsible for the unique optical, thermal, acoustic, mechanical, and electrical properties of organic aerogels, there are certain applications in which a larger scale structure is also desired in combination with the unique features of the aerogel. In order to achieve this goal, we have been emulsifying our resorcinol-formaldehyde sols to form foams which retain the aerogel framework but have some cells/pores as large as 2 {mu}m. In another approach, we have infused an emulsion-derived polystryene foam with a resorcinol-formaldehyde sol to form a new composite foam. This paper addresses the chemistry-structure-property relationships of organic aerogels, their emulsion-derived derivatives, and composite foams.

• Research Organization: Lawrence Livermore National Lab., CA (United States)
• Sponsoring Organization: DOE; USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7030589
• Report Number(s): UCRL-JC-109956; CONF-921110--25; ON: DE92019575
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation &amp; Manufacture
ALDEHYDES
AROMATICS
CARBON
CHEMICAL REACTIONS
COLLOIDS
COMPOSITE MATERIALS
COMPRESSION
DECOMPOSITION
DENSITY
DEVELOPERS
DISPERSIONS
ELECTRON MICROSCOPY
ELEMENTS
EMULSIONS
FOAMS
FORMALDEHYDE
GELS
HYDROXY COMPOUNDS
MATERIALS
MICROSCOPY
NONMETALS
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PETROCHEMICALS
PETROLEUM PRODUCTS
PHENOLS
PHYSICAL PROPERTIES
PLASTICS
POLYMERIZATION
POLYMERS
POLYOLEFINS
POLYPHENOLS
POLYSTYRENE
POLYVINYLS
PYROLYSIS
RESORCINOL
SCANNING ELECTRON MICROSCOPY
SOL-GEL PROCESS
SYNTHESIS
SYNTHETIC MATERIALS
THERMAL CONDUCTIVITY
THERMOCHEMICAL PROCESSES
THERMODYNAMIC PROPERTIES