Accession Number:

ADA621044

Title:

New Approaches to Maximizing Thermo-oxidation Resistance of Polycyanurate Networks

Descriptive Note:

Briefing charts

Corporate Author:

AIR FORCE RESEARCH LAB EDWARDS AFB CA

Personal Author(s):

• Guenthner, Andrew J.
• Davis, Matthew C.
• Vij, Vandana
• Yandek, Gregory R.
• Lamison, Kevin R.
• Reams, Josiah T.
• Haddad, Timothy S.
• Mabry, Joseph M.

Report Date:

2014-08-13

Pagination or Media Count:

20.0

Abstract:

Among thermosetting resins, polycyanurate networks derived from cyanate ester monomers offer excellent flame, smoke, and toxicity characteristics along with enhanced thermo-oxidative stability compared to epoxy resins. Recent structure-property investigations in polycyanurate networks have revealed new insights into the relationship between the chemical moieties found in the networks and the corresponding levels of thermo-oxidative resistance. In particular, it appears that the presence of methyl groups next to tertiary or quaternary carbons has a decidedly negative impact on thermo-oxidative stability during TGA heating ramp tests. In the case of silicon-containing cyanate esters, thermo-oxidative stability can be improved significantly by the incorporation of silicon only in cases where either a large portion of the chemical repeat unit is formed from inorganic groups, or the thermo-oxidative stability of the carbon-containing analog is relatively poor compared to other organic polycyanurate networks.

Descriptors:

• *CYANATES
• CHEMICALS
• ESTERS
• MONOMERS
• THERMAL STABILITY
• THERMOSETTING PLASTICS

Subject Categories:

• Organic Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE