ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
An investigation has been carried out to determine the influence of operating conditions on the character of the final product resulting from the polymerization of ethylene in a radio-frequency discharge. It has been found that low pressures and high ratios of discharge power to gas flow rate lead to the deposition of a powder as well as a film. From visual observations of powder deposition, it has been possible to divide the plane formed by the axis of pressure and flow rate into a region in which powder is deposited together with a film and a region in which only a film is deposited. Numerous physical measurements have been carried out in order to characterize the powder. From these measurements, it has been concluded that the powder is a relatively dense, amorphous, and highly crosslinked polymer composed of short-chain segments containing no more than two adjacent methylene groups. Many forms of unsaturation have been observed which, together with the high crosslink density, explain the measured hydrogen-to-carbon ratio of 2.7 to 2. Evidence of oxidation has been observed through the appearance of hydroxyl and carbonyl bands in the infrared spectrum of the polymer. A mechanism for the formation of the powder has been proposed which suggests that the polymerization of the powder takes place totally in the gas phase.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1973.070170318
Permalink
