ISSN:
0032-3888
Schlagwort(e):
Chemistry
;
Chemical Engineering
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
,
Physik
Notizen:
The Contraves balance rheometer has been used in a study of the gelation and fusion process of three DOP-based PVC-plastisols and the results compared with those obtained with the Brabender plastograph. The tensile properties of samples fused at different temperatures have also been determined. The rheometer results relate to the temperature dependence of the viscosity, shear modulus, and loss angle of the plastisols used. The viscosity- and modulus-temperature curves are to some extent reminiscent of the torque-temperature curves obtained with the plastograph; the fusion temperatures are slightly different. The loss-angle-temperature curves measured with the rheometer exhibit sharp maxima in the vicinity of the Tg-point of the base polymer. The shear modulus decreases with time when the temperature is kept constant (above the fusion point). This effect is possibly associated with crystallite melting. The temperature necessary to reach the maximum strength plateau of films fused at various temperatures was found to agree (within 10°C) with the maximum in the modulus-temperature curves (minimum in loss-angle-temperature curves) when the rheometer shear rate was sufficiently low. On the whole, the rheometer allows for better temperature control. Also, the fact that the results are given in terms of viscosity and shear modulus may have some advantage in interpreting gelation and fusion data.
Zusätzliches Material:
6 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/pen.760141210
