HANSER Hanser Publishers, Munich • Hanser Gardner Publications ...
HANSER Hanser Publishers, Munich • Hanser Gardner Publications ...
HANSER Hanser Publishers, Munich • Hanser Gardner Publications ...
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where<br />
Mw = molecular weight<br />
JC — resin dependent constant<br />
The approximate value of JC for LDPE is<br />
JC = 2.28 <strong>•</strong> 10" 4<br />
and for polyamide 6<br />
K'= 5.21 <strong>•</strong> 10" 14<br />
according to the measurements of LAUN [21].<br />
These values are based on zero viscosity.<br />
1.3.7.8 Viscosity of Two Component Mixtures<br />
The viscosity of a mixture consisting of a component A and a component B can be<br />
obtained from [17]<br />
where<br />
7] = viscosity<br />
C = weight per cent<br />
Indices:<br />
M: mixture<br />
Ay B: components<br />
1.4 Viscoelastic Behavior of Polymers<br />
(1.48)<br />
Polymer machinery can be designed sufficiently accurately on the basis of the relationships<br />
for viscous shear flow alone. However, a complete analysis of melt flow should include<br />
both viscous and elastic effects, although the design of machines and dies is rather difficult<br />
when considering melt elasticity and therefore rarely used. WAGNER [18] and FISCHER<br />
[19] made attempts to dimension dies taking elastic effects into account.<br />
For a more complete picture of melt theology the following expressions for the viscoelastic<br />
quantities according to LAUN [20, 21] are presented. The calculation of the deformation<br />
of the bubble in film blowing is referred to as an example of the application of Maxwell's<br />
model.