Influence of Mold Temperature on the Internal Structure and Creep Variation in the Thickness Direction of sPS Injection Moldings
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K. Banik
Abstract
In this work, an effort was made to study the effect of mold temperature variation on the creep behavior of syndiotatctic polystyrene (sPS) injection moldings. The resulting molecular orientation, crystallinity and molecular packing density in the moldings due to processing were characterized to understand the creep variation in the thickness direction. The moldings were sliced off in definite layers by milling from both the surfaces and the creep behavior was characterized. The results indicated that the development of internal structures and the resulting creep behavior is strongly interdependent with creep strain decreasing as the core of the molding is reached. A higher mold temperature generally freezes-in more crystalline regions and enhances the molecular packing density inside the part that affects the tendency to creep. The frozen-in molecular orientation on the other hand showed only a negligible effect.
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© 2007, Carl Hanser Verlag, Munich
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Articles in the same Issue
- Contents
- Contents
- Regular Contributed Articles
- Characteristic Curves based on 3D Non-isothermal Flow Computations in Single-screw Extruder for Non-Newtonian Fluids
- Investigation on the Structure and Properties of Different PE Blown Films
- Influence of Mold Temperature on the Internal Structure and Creep Variation in the Thickness Direction of sPS Injection Moldings
- Preparation of Foam from PVC Plastisol
- Effects of Zinc Salts of Sulfonated Natural Rubber on Mechanical Properties, Morphology and Compatibility of Natural Rubber/Chlorosulfonated Polyethylene Blends
- Polypropylene-Clay Nanocomposites Fibers Structure and Performance
- Rapid Communications
- Constant Temperature Microfeature Embossing with Slowly Crystallizing Polymers
- PPS News
- PPS News
- Seikei-Kakou Abstracts
- Seikei-Kakou Abstracts