About Gneuss Online Viscometer
|
|
Posted On :
Nov-18-2011
| seen (429) times |
Article Word Count :
455
|
|
To ensure product quality and operating efficiency in processing efficiency sensitive polymers, it is crucial to monitor treatment of some key polymers parameters.For that degrade due to hydrolysis, shear, or due to thermal and / or oxidation, is ex very useful to control the viscosity of the polymer line.
|
|
To ensure product quality and operating efficiency in processing efficiency sensitive polymers, it is crucial to monitor treatment of some key polymers parameters.For that degrade due to hydrolysis, shear, or due to thermal and / or oxidation, is ex very useful to control the viscosity of the polymer line.
The example the case described here is the treatment of PET sheet for thermoforming. Under the temperature and moisture is present, the chain of molecular weight decreases. The influence of humidity on the molecular weight of the viscosity of PET (which is
IV, the measured intrinsic viscosity) with different humidity levels during the same time and there
The same temperature is shown in figure 1
Figure 1: Polyester polymer degradation by hydrolysis of IV to melt as a function of water content (280 ° C, the retention time of 1 min), the graph makes it clear that in dealing with the PET
sheet for thermoforming, residual moisture or drying efficiency (in addition to temperature, Reside in this case, the shear stress and pressure) has a significant
effect on the properties of the polymer melt.
If the viscosity of the droplets of polymers which have a serious negative effect on the mechanical properties of the final product. The low molecular weight, will result in tensile strength and decreases when the blade is (in a later production process), the containers moformed deep, thin walls, the thin wall of the container is prone to explode . Another problem is to maintain a uniform thickness of metal tolerance Rances if the viscosity of the polymer varies as the material flows through the death differently depending on the viscosity.
A major reason for various residues variable residence time companion of one hundred drying equipment, drying temperature, dew point gas drying and theimpact in contact with ambient air.
Although all
above factors are held constant, the residual moisture of the material input can vary (eg, season), leading to the melt viscosity and molecular weight of the film. It is well known that problems arise, for example, during the passage of
drying unit to another.
To reduce the effects of changes in viscosity, producers of PET sheet for thermoforming generally produce thick plates as necessary
Reby to use more product than necessary.
By controlling the viscosity, it is possible for producers to adopt corrective measures. Measurement of molecular weight and intrinsic viscosity are typical
ment as possible with the development of complex laboratory equipment, not in real time.
For this reason, a simple and reliable real-time viscosity measurement (and the ability to correlate the intrinsic value of viscosity) offers valuable opportunities for a producer of PET film.
|
|
|
|
Article Source :
http://www.articleseen.com/Article_About Gneuss Online Viscometer_106224.aspx
|
|
Author Resource :
Visit viscometer.co for all types of viscometer according to your need.
|
|
Keywords :
viscometer, digital viscometer,
Category :
Product Reviews
:
Digital Products
|
|
|
|
