SYNTHESIS AND EVALUATION OF THERMALLY STABLE POLYMERS. PART I. POLYMER SYNTHESIS. PART II. POLYMER EVALUATION

Technical Report · Mon May 01 00:00:00 EDT 1961

OSTI ID:4044443

Brown, G P; Goldman, A; Doyle, D C

Poly-m-phenoxylene was synthesized with number average molecular weights approaching 4,000 and, in one case, a weight average molecular weight of 6,800. The synthesis routes studied included self-condensation of alkali metal salts of m-bromophenol, condensation of salts of resorcinol with m-dibromobenzene, and self-condensation of resorcinol. In addition to polymer, four syntheses provided small amounts of crystalline material indicated as being cyclic oligomers, presumably trimer and tetramer. Study of a variety of reaction conditions indicates that anhydrous conditions are essential to minimize carbon-carbon coupling; and that purity of the starting material m-bromophenol is probably the most important cause for failure, as yet,to achieve higher molecular weights, but that low rates of reaction under heterogeneous conditions may adversely affect molecular weights by promoting cyclization reactions. A single sample of poly-m-phenoxylene, having low functional group content, was tested via thermogravimetric analysis and was shown to possess outstanding thermal stability, 3% weight loss up to 500 deg C. The results of concluding thermal stability studies and preliminary heatsoftening studies are presented. Topics treated include: methods of kinetic analysis of thermogravimetric data, illustrated for zero-order (octamethylcyclotetrasiloxane) and first-order (polytetrafluoroethylene) volatilization; effects of varying sample geometry in thermogravimetry; thermoparticulate analysis as a means of observing incipient and vestigial volatilization; differential thermal analysis, volume dilatometry, x-ray and electron diffractometry, methods of observing mechanical, electrical and nuclear magnetic relaxation effects, and a new heat-softening test. As a part of the study of nuclear magnetic resonance, some styrene-divinylbenzene copolymers of various degrees of cross-linking are compared. (auth)

• Research Organization: General Electric Co. General Engineering Lab., Schenectady, N.Y.
• DOE Contract Number: AF33(616)-7076
• NSA Number: NSA-15-022193
• OSTI ID: 4044443
• Report Number(s): WADD-TR-61-255
• Resource Relation: Other Information: Orig. Receipt Date: 31-DEC-61
• Country of Publication: United States
• Language: English

Related Subjects

CHEMISTRY
ALKALI METALS
BENZENE
BONDING
BROMINATED HYDROCARBONS
CARBON
CHEMICAL REACTIONS
DIFFRACTION
FLUORINATED HYDROCARBONS
HEATING
MOLECULES
NUCLEAR MAGNETIC RESONANCE
PHENOLS
POLYETHYLENES
POLYMERS
PREPARATION
QUALITATIVE ANALYSIS
RESORCINOL
SALTS
SILICONES
STABILITY
STYRENE
VINYL RADICALS
WEIGHT
X RADIATION