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:
Stable, high molecular weight polymers of formaldehyde have been studied to determine their molecular structure. The polymer chain was shown to be a polyoxymethylene by chemical analysis and infrared absorption spectra. Infrared techniques also revealed hydroxyl end groups which were replaced by acetate groups on esterification. The endgroups, which were also measured by chemical methods, were used to determine the number-average molecular weight over the range 20,000 to 98,000. Values obtained by assuming two endgroups per molecule agreed with osmotic pressure results, thus showing this to be an essentially unbranched polymer. Two theoretically possible branch-point structures were investigated by chemical methods; none could be detected, further indicating a linear polymer structure. Indirect evidence of narrow molecular weight distribution was obtained by comparing melt viscosity properties with those of other polymers of known wide and narrow distribution.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1959.070010206
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