Structure of polypropylene parts from multicavity injection mould

• Autorzy: Jaruga T. , Bociąga E.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The examination of structure of injection moulded parts, coming form different cavities of injection mould with geometrically balanced runners, was the purpose of this research. The parts were manufactured from polypropylene. Design/methodology/approach: The method of optical microscopy was used. The samples were prepared from microtomed slices from parts and next they were observed in polarized light. The skin-core morphology was analyzed and spherulitic structure was described by spherulites size measuring. Findings: The differences in morphology and spherulite size for parts from particular mould cavities were found. They are caused by different thermal conditions in each cavity. Research limitations/implications: An injection mould with geometrically balanced runners was used for investigation. The differences in parts' structure occur for each injection mould, but they are dependent on the cavities layout and runners configuration. Practical implications: Knowledge about the differences in structure of parts from different cavities is the reason to look to the solution by minimizing the temperature inequality in the injection mould. Originality/value: Despite using geometrically balanced runners the cavities are not filled equally and the parts have different structure. In some recent works the issue of flow imbalance in multicavity injection moulds was analyzed and even some solutions of this problem were proposed. All investigation was focused on simultaneous plastic flow into all cavities, but there were no investigation of parts' structure and properties.

Słowa kluczowe

EN

plastic forming; injection moulding; polymer structure

PL

obróbka plastyczna; wtryskiwanie; budowa polimerów

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2007
• Tom: Vol. 28, nr 7
• Strony: 429--432
• Opis fizyczny: Bibliogr. 16 poz., il., wykr.

Twórcy

autor

Jaruga T.

autor

Bociąga E.

• Institute of Polymer Processing and Production Management, Częstochowa Univesity of Technology, Al. Armii Krajowej 19c, 42-200 Częstochowa, Poland,

Bibliografia

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