Accession Number : ADA304641

Title :   On-Line Mass Spectrometric Monitoring of the Polymerization of a Phenolic-Resin-Based Material.

Descriptive Note : Technical note,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER

Personal Author(s) : Aikens, David A. ; Wood, George M. ; Upchurch, Billy T.

PDF Url : ADA304641

Report Date : DEC 1975

Pagination or Media Count : 15

Abstract : Polymerization of phenolic-resin-based materials requires elevated temperatures. The low thermal conductivity of these materials has led to the use of dielectric heating techniques in lieu of standard convection oven heating to obtain a satisfactory cure. The curing rate and therefore the quality of the cured material depends on the heating rate and the maximum temperature attained, parameters which are extremely difficult to measure in dielectric heating units. The dielectric curing of these materials has been monitored by using a mass spectrometer to measure the partial pressure of phenol in the gas evolved during polymerization. The resulting plots of phenol partial pressure as a function of time have a characteristic shape, and these may be used to indicate the attainment of complete curing. The validity of the mass spectrometric technique was confirmed by chemical analysis of the polymerized samples.

Descriptors :   *POLYMERIZATION, *PHENOLS, *MASS SPECTROMETRY, MONITORING, REAL TIME, COMPOSITE MATERIALS, HIGH TEMPERATURE, DIELECTRICS, PRESSURE MEASUREMENT, THERMAL CONDUCTIVITY, VOLATILITY, MASS SPECTROMETERS, CURING, ONLINE SYSTEMS, CONVECTION(HEAT TRANSFER), CONCENTRATION(CHEMISTRY), FORMALDEHYDE, PHENOLIC PLASTICS, PARTIAL PRESSURE.

Subject Categories : Polymer Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE