Polymer Gels as Precursors to High-Performance Materials
Abstract
The three types of materials covered in this investigation were (1) thermoreversible gels of organic polymers (such as polyethylene), (2) non- reversible gels obtained by the hydrolysis of organometallics and used as precursors to inorganic ceramics (silica and titania), and (3) hybrid composites prepared by having siloxane polymers present during the in-situ generation of the ceramic species. The kinetics of the gelation process were determined by measuring the shear moduli of the gels as a function of time for various compositions and catalyst concentrations. Of particular interest was the observed decreases in gelation time with increase in concentration of either catalyst (through increases in reaction rates) or polymer (through increases in the number of high molecular weight species necessary for gelation). Composites obtained by densification of the gels were characterized by NMR imaging, neutron and x-ray scattering, and impact strength measurements. The polymer components in the hybrid organic-inorganic composites was found to greatly increase their impact strengths.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 06, 1993
- Accession Number
- ADA270937
Entities
People
- J. E. Mark
Organizations
- University of Cincinnati