ISSN:
0032-3888
Keywords:
Chemistry
;
Chemical Engineering
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:
The flow behavior of molding compounds such as phenolics, melamines, and ureas was examined by a monohole flow test in which the compounds were high frequency-preheated up to the test temperature just prior to being put into the monohole mold. The effect of temperature, pressure, and water content on the flowability has been clarified as follows: (1) The relation between log flow rate and reciprocal absolute temperature consists of two straight lines with different slopes, showing dual activation energies for flow above and below an inflection point. The phenomenon suggests the existence of a phase transition in a resin flow. (2) The inflection point shifts to the lower temperature side with an increase of pressure and water content. (3) The influence of water content on the flowability varies largely according to compatibility between resins and water. (4) The temperature dependence of flow rate in a urea compound decreases during storage due to the advancement of condensation.
Additional Material:
9 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pen.760210508
