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1

Modification of substandard EPDM with amorphous thermoplastic polyesters (PETG and PEF): microstructure and physical properties

Paszkiewicz S., Irska I., Piesowicz E.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 2

8--14

EN

The phase morphology, thermal behavior and mechanical properties of two series of polymer blends based on ethylene/propylene/diene rubber (EPDM) and amorphous homologues of poly(ethylene terephthalate), i.e. glycol modifi ed poly(ethylene terephthalate) (PETG) and poly(ethylene furanoate) (PEF), were investigated. The morphology of the blends shows a two phase structure in which the minor phase (amorphous polyester) is dispersed as domains in the major (EPDM) continuous matrix phase. Differential calorimetry studies confi rmed that both systems were immiscible and exhibits two glass transitions. The melting peak area of EPDM in the blends decreased as the amount of the other component increased. The values of stress at strain of 100% were improved upon the increasing content of PETG in EPDM system, while only slight decrease of this value was observed. Moreover, the strong improvement of hardness and thermo-oxidative stability along with an increasing content of amorphous polyester phase was reported.

2

Effect of Manganese and Iron Content on Morphology of Iron Intermetallic Phases in AlSi7Mg0.3 Alloy

Podprocká R., Bolibruchová D.

Archives of Foundry Engineering

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2018

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Vol. 18, iss. 2

95--99

EN

Iron is presented as an impurity in Al-Si alloys and occurs in the form of the β-Al5FeSi phase formations. The presence of iron and other elements in the alloy causes the formation of large intermetallic phases. Due to the high brittleness of this phase, it reduces the mechanical properties and increases the porosity. Manganese is used to inhibit the formation of this detrimental phase. It changes the morphology of the phase to polyhedral crystals, skeletal formations, or Chinese script. The present article deals with the influence of various amounts of manganese (0.1; 0.2; 0.4; 0.6 wt. %) on the formation of iron-based intermetallic phases in the AlSi7Mg0.3 alloy with different levels of iron content (0.4; 0.8, 1.2 wt. %). The increase of iron content in each alloy caused the creation of more intermetallic compounds and this effect has been more significant with higher concentrations of manganese. In alloys where the amount of 1.2 wt. % iron is present, the shape of eutectic silicon grain changes from angular to short needle type.

3

Phase Morphology of Polypropylene-Polyethylene Terephthalate Blend Fibres

Körmendy E., Marcinčin A., Hricová M., Kovačic V.

Fibres & Textiles in Eastern Europe

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2005

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Vol. 13, no. 1 (49)

20--23

EN

The article deals with the phase morphology of polypropylene-polyethylene terephthalate (PP/PET) blend fibres. The development of the morphology of the blend PP/PET fibres in the spinning and drawing processes, in dependence on molecular weight and the rheological properties of PET in the dispersed phase has been investigated. In experimental work both the length and diameter of PET deformed particles in PP matrix have been evaluated. In general, it was found that the length of the PET microfibrils in PP fibres after spinning and drawing is indirectly proportional to the molecular weight of the PET. However, in the drawing process the increment of the microfibril length of the dispersal phase is higher for PET with a higher molecular weight in comparison to the length after spinning. This means that the length of PET particles in the PP matrix is strongly influenced by spinning conditions for a lower molecular weight of PET and by the drawing conditions for a higher molecular weight of PET.

PL

Artykuł dotyczy morfologii fazowej włókien z mieszaniny polipropylenu i poli(tereftalanu etylenu). Badano morfologię włókien z mieszaniny PP/PET podczas przędzenia i rozciągania, w zależności od ciężaru cząsteczkowego i właściwości reologicznych PET w fazie dyspersyjnej. Oceniano eksperymentalnie długość i średnicę zdeformowanych cząstek PET w matrycy PP Stwierdzono, że zasadniczo długość mikrofibryl PET we włóknach PP po przędzenia i rozciąganiu zależy odwrotnie proporcjonalnie od ciężaru cząsteczkowego PET. Jednakże, przyrost długości mikrofibryl w fazie dyspersyjnej w stosunku do długości po przędzeniu jest w procesie rozciągania wyższy dla PET o wyższym ciężarze cząsteczkowym. Oznacza to, że długość cząstek PET w matrycy PP jest silnie zależna od warunków przędzenie dla PET o niższym ciężarze cząsteczkowym, i od warunków rozciągu dla PET o wyższym ciężarze cząsteczkowym.