Polyplastics Co,.Ltd.

 HOME  > Technical support > Molding technology > Molding technology for DURANEX(R) PBT

Selection of molding conditions

Contents Introduction Selection of molding conditions Moldability Quality of molded products
 Mold design Safety Precautions

>>> [ Standard Molding Conditions ] [ Predrying ] [ Cylinder Temperature ] [ Molding Cycle ] <<<


2.3  Cylinder Temperature

Because the melting point of DURANEX® is around 228℃,the appropriate material temperature is from 240℃ to 260℃. If the temperature exceeds 280℃, decomposition begins; therefore, a temperature around 270℃ should be considered as the upper limit. The effects of cylinder temperatures and residence time in the heated cylinder on mechanical properties of DURANEX 3300 and 3316 are shown in Fig. 1-4, 1-7 in the (a) and 1-8, 1-11 in the (b) It is a matter of opinion what value should be regarded as the limit but in Table 1-1, the longest allowable residence times are estimated from such points as the melt index rises to 2 times of its initial value and the color Difference Meter more than 2.5 of their original levels.

As a precaution to prevent deterioration of property, full attention must be paid to cylinder temperature and the residence time in Table 1-1 as well as to moisture content.

 

Table 1-1 Cylinder temperature vs. allowable residence time of DURANEX®
Grade
Cylinder temperature
250℃
270℃
3300
30min
20min
3316
30min
10min
Caution : Keep in mind that the material temperature, though it depends on the injection machine type, is usually higher by 5 to 10℃ than the cylinder temperature.

 

 

(a) Residence Time in the Heated Cylinder vs. Various Properties of DURANEX 3300

 

Duranex fig.1-5 Duranex fig.1-5

Duranex fig.1-6Duranex fig.1-7

 

 

 

(b) Residence Time in the Heated Cylinder vs. Various Properties of DURANEX 3300

 

Duranex fig.1-9

Duranex fig.1-10Duranex fig.1-11

 

 


>>> [ Standard Molding Conditions ] [ Predrying ] [ Cylinder Temperature ] [ Molding Cycle ] <<<

Contents Introduction Selection of molding conditions Moldability Quality of molded products
 Mold design Safety Precautions

 

 

Fake Products on Market

Recommended browser is Internet Explorer ver 8.0 or higher.

OUTPUT PAGE

WEB@TSC
Technical Documents PDF Plastic Pavilion Group introduction movie