Autor: Valeria Dulio, Riccardo Po, Raffaella Borrelli, Alessandro. Guarini, Claudio Santini
Rok vydání: 1995
Předmět:
Zdroj: Angewandte Makromolekulare Chemie. 225:109-122
ISSN: 1522-9505
0003-3146
Popis: Low-molecular-weight compounds extracted from recycled poly(ethylene terephthalate) (PET) from post-consumer soft-drink bottles, treated at 150–220°C in vacuo or extruded at several temperatures and two different mass flow rates, were characterized by high performance liquid chromatography (HPLC), size exclusion chromatography (SEC) and desorption chemical ionization/mass spectrometry (DCI/MS). Among these products, cyclic and linear oligomers (polymerization degree 2–6) were identified, and their distribution was determined. As a consequence of vacuum treatment of PET, the overall oligomer content decreases with increasing temperatures. Conversely, the extrusion at crescent temperatures causes an increase of the oligomer concentration; the same effect was observed by increasing the residence time. A further effect was represented by the enlargement of molecular weight distributions, i.e. larger rings and longer chains were formed in greater amounts at higher temperatures and residence times; a significant fraction of medium-molecular-weight oligomers (Mn = 1400–1900) was also formed.
Databáze: OpenAIRE
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