Solvent effects on silica domain growth in silica/siloxane composite materials
- Sandia National Labs., Albuquerque, NM (United States)
- Univ. of Cincinnati, Cincinnati, OH (United States)
- Dow Corning Corp., Midland, MI (United States)
The effect of solvent addition on the phase separation, mechanical Properties and thermal stability of silica/siloxane composite materials prepared by in situ reinforcement was examined. The addition of a solvent enhances the miscibility of the reinforcement precursor, a partial hydrolyzate of tetraethoxysilane (TEOS-PH), with the polydimethylsiloxane (PDMS) polymer. As a result, the phase separation at the micron level, termed the large-scale structure, diminished in size. This decrease in particle size resulting from the addition of moderate amounts of solvent was accompanied by an improvement in the mechanical properties. However, solvent addition in the excess of 50 weight percent led to a decrease in mechanical properties even though the large-scale structure continued to diminish in size. Small Angle X-Ray Scattering (SAXS) was used to examine the Angstrom level or small-scale structure. This small-scale structure was only affected by the presence of solvent, not the amount. The silica/siloxane composite materials showed the same thermal transition temperatures as the original PDMS material.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 95318
- Report Number(s):
- SAND--95-1331C; CONF-951033--5; ON: DE95014838; CRN: C/SNL--SC9101028
- Country of Publication:
- United States
- Language:
- English
Similar Records
Molecular Dynamics Studies on the Effects of Water Speciation on Interfacial Structure and Dynamics in Silica-Filled PDMS Composites
Molecular weight dependence of domain structure in silica-siloxane molecular composites