PBT is solvent-resistant at room temperature and can withstand a continuous operating temperature of 230° F. It offers excellent dimensional stability with high creep resistance and low moisture absorption. Because the material crystallizes rapidly, mold cycles are short and molding temperatures can be lower than for many engineering plastics. Compared to PET, it has somewhat lower strength and rigidity but is more flexible and tougher (higher impact strength). Now start moulding parts in the purging material until all drops are clear of PBT. 2.3 Cylinder Temperature.

It also has a sligtly lower melting point and crystallizes much faster than PET. Hot Runner Temperature. They are crystalline materials with sharp melting and freezing points, which have good flow characteristics and mold in fast cycles. See below for our chart on plastic processing and drying temperatures, along with plastic and abs molding temperatures. The temperature where entire chain movement occurs is called the melting point (Tm) and is greater than the Tg PBT melting point (approximately 225C [437F]) and heat distortion temperatures are lower than for PET.

55 - 110 o C. Run at upper end of range for best surface finish. The glass transition temperature ranges from 22C-43C [71F-109F]. Heat Deflection Temperature @264 psi ºF Melting Point ( Crystalline ) ºF Continuous Service Temperature in Air ºF Thermal Conductivity ºF ELECTRICAL Dielectric Strength, Short Term Volts/mil Volume Resistivity Ohms-cm 4.5 x 10 16 Dielectric Constant 60 Hz Dissipation Factor 60 Hz PBT Polyester 1.31 9,400 50 425,000 Santa Fe Springs, CA 562-968-2100 - Fremont, CA 510-770-1500 - … Melt temperature: 280-310°C ; Mold temperature: 140-160°C to obtain a crystalline PET (for technical applications) For transparent applications, mold temperature should lie between 10 and 50°C; Screw with an L/D ratio of 18-22 is recommended; Extrusion. The processing details in this manual will enhance part quality and productivity. When PET was introduced its melt processing temperature was beyond the range of most injection moulding machines at that time and PBT was introduced as a thermoplastic with many of the properties of PET but had a lower processing temperature. It has a sligtly lower melting point but greater chain flexibility. 245 - 270 o C. ... DO NOT shut down with PBT in the machine barrel of hot runner system. This thermoplastic polyester has very good dimensional stability. Because the melting point of DURANEX® PBT is around 224°C,the appropriate resin temperature is from 250°C to 270°C. While all types of Crastin® PBT are based on PBT, the product line can be divided into groups with com-mon performance advantages. The glass transition temperature ranges from 22C-43C [71F-109F].

It also exhibits high heat resistance, chemical resistance and good electricals. 2.3 Cylinder Temperature. Shrinkage is of the order of 0.015-0.028 mm/mm [1.5 -2.8%].

245 - 270 o C. Must be measured with a pyrometer by taking an airshot through the injection machine nozzle. Another high volume polyester is PBT.

Specific Injection Pressure.

If the temperature exceeds 280°C, decomposition begins; therefore, a temperature around 270°C should be considered as the upper limit. Medium To Fast. The Vicat softening point is approximately 170C [338F]. Melt Temperature.