RESEARCH AND DEVELOPMENT OF HIGH TEMPERATURE STRUCTURAL ADHESIVES
Abstract
Elemental analyses of a phenolic resin after pyrolysis in an inert atmosphere gave additional support to the postulated formation of condensed ring systems. In situ syntheses of semi-inorganic polymers through pyrolysis of siliconephenolic laminates in the presence of H2S at 1500 F resulted in specimens with improved oxidation resistance. Constructive pyrolysis of phenolic laminates at 1800 F showed very large decreases in volume resistivity. Arsenic thioarsenate cure of epoxy-novolac adhesive at lower cure temperature eliminated smoking, but the resulting bonds had poorer tensile shear strengths. Antimony thioarsenate was inferior to arsenic thioarsenate as a curing agent for epoxy-novolac adhesive. Oxidative pyrolysis of bis(2-hydroxyphenyl)methane at 290 to 295 C resulted in dehydration of the hydroxy groups and in cleavage of the methylene bridges. Oxidation of bis(2-hydroxyphenyl)-sulfide at 260 C yielded some spectroscopic evidences for formation of sulfoxide and sulfone moieties. Pyrolysis of diphenyldifluoromethane at 220 to 230 C in the presence of air resulted mostly in benzophenone formation. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 15, 1962
- Accession Number
- AD0276048
Entities
People
- Harold H. Levine
- Sven H. Ruetman