Predrying conditions before molding

Drying conditions. Required drying time is dependent on the thickness of resin layer. Normally 10 h or more at 356°F (180°C) is recommended. 

A shelf-type dryer with hot air circulation with a temperature control range of 392°F (200°C) or more is recommended. 

TABLE 10.8 Aurum Melt Viscosity and Molecular Weight 

Grade Melt viscosity, P, at 752°F (400°C) Melt flow, g/10 min, at 752°F (400°C) Molecular weight, LALLS  

At least 356°F (180°C) is required for predrying in order to keep less than 100 ppm, which is needed to obtain appropriate molded parts. An exposure to air even after drying can result in moisture absorption that affects molded parts. Before molding, resin should be removed from conditions of moisture. 

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