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DURANEX thermoplastic polymer, commonly known as PBT
(Polybutylene telephthalate), is a highly crystalline plastics.
DURANEX is available in a wide variety of grades in four
categories as shown below.
- Unreinforced grades and grades reinforced
with glass fiber and/or other inorganic fillers.
- Slow burning and flame retardant grades.
Because the heat deflection temperatures of
unreinforced grades are not sufficiently high for some industrial
applications, most molded parts are made of reinforced grades;
therefore, considerations to prevent deformation in molding
are essential. Through such considerations include design of
product shapes, mold design, and selection of grades, only the
first two of these will be explained in this section.
DURANEX contains ester linkage in its
polymer chain and care should be taken to avoid polymer degradation
due to hydrolysis throughout the molding operation. Key points
regarding this problem are how to control moisture level of
the pellets, material temperature and the residence time in
the cylinder.
Some aspects of general mold design for DURANEX are
common to those for DURACON, so we recommend that you
also refer to "Molding
technology for DURACON".
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Molding technology for Duranex