Reactive extrusion of recycled poly(ethylene terephthalate) with polycarbonate by addition of chain extender

Film blowing of Poly(ethylene terephthalate) (PET) is challenging due its inherently low melt viscosity and poor melt strength. In this study, it is shown how the rheological properties of a commercial PET can be altered by reactive extrusion using either pyromellitic dianhydride (PMDA) or a multifunctional epoxy (Joncryl® ADR 4368) as chain extender, in order to improve the processing behavior during film blowing. The modified materials were characterized by shear and elongation rheometry and relevant processing characteristics, like melt pressure, bubble stability, and film thickness uniformity, were used to assess the influence of the type of modifier on processing and product performance. It is shown that PMDA is useful to increase the melt strength which leads to an improved bubble stability, while epoxy modified PET shows a reduced drawability that can cause problems at high take-up ratios. On the other hand, the epoxy modifier indicates a pronounced strain hardening during elongational deformation, and therefore leads to a better film thickness uniformity compared to the neat PET and the PET modified with PMDA. The differences with respect to processing performance are discussed and ascribed to the molecular structure of the materials.

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Chain Extension and Thermal Behavior of Recycled Poly(Ethylene Terephthalate) Modified by Reactive Extrusion with Triphenyl Phosphite

MATEC Web of Conferences ◽

10.1051/matecconf/20166706052 ◽

2016 ◽

Vol 67 ◽

pp. 06052 ◽

Cited By ~ 1

Author(s):

Dan Qin ◽

Chaosheng Wang ◽

Huaping Wang ◽

Xiaoting Jiang

Keyword(s):

Thermal Behavior ◽

Ethylene Terephthalate ◽

Reactive Extrusion ◽

Chain Extension ◽

Triphenyl Phosphite ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene

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Tensile and Impact Properties of Recycled Poly(Ethylene Terephthalate) and Polycarbonate Composites Reinforced with Silane Treated Hollow Glass Microspheres

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.772.33 ◽

2018 ◽

Vol 772 ◽

pp. 33-37

Author(s):

Nattakarn Hongsriphan ◽

Pajaera Patanathabutr ◽

Kanyakarn Lappokachai

Keyword(s):

Mechanical Properties ◽

Interfacial Adhesion ◽

Ethylene Terephthalate ◽

Chain Extender ◽

Glass Microspheres ◽

Hollow Glass Microspheres ◽

Hollow Glass ◽

Poly Ethylene Terephthalate ◽

Fixed Composition ◽

Poly Ethylene

Recycled poly (ethylene terephthalate) or R-PET is conventionally melt blended with polycarbonate with the presence of chain extender in order to produce polymer blend that provides good mechanical properties and cost effectiveness. This research was carried out to improve properties of such a blend by compounding them with silane treated hollow glass microspheres (HGMs), which mixing procedure was emphasized how it could affect mechanical properties. R-PET/PC/HGM composites of a fixed composition were melt compounded with three different mixing procedures. It was found that the compounding HGMs with PC and then R-PET obtained the most rigidity specimens than the all-in-one compounding or the compounding HGMs with R-PET and then PC. Silane treated HGMs were well distributed in the polymer matrix presenting good interfacial adhesion. However, the notched impact strength of all composites were inspected to be in the same range.

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Improving the properties of recycled PET/PEN blends by using different chain extenders

Journal of Polymer Engineering ◽

10.1515/polyeng-2015-0268 ◽

2016 ◽

Vol 36 (6) ◽

pp. 615-624 ◽

Cited By ~ 3

Author(s):

Simge Can ◽

N. Gamze Karsli ◽

Sertan Yesil ◽

Ayse Aytac

Keyword(s):

Ethylene Terephthalate ◽

Chain Extender ◽

Degree Of Crystallinity ◽

Recycled Pet ◽

H Nmr ◽

Loading Level ◽

Poly Ethylene Terephthalate ◽

Chain Extenders ◽

Izod Impact ◽

Poly Ethylene

Abstract The main aim of this study was to improve the mechanical properties of the recycled poly(ethylene terephthalate)/poly(ethylene 2,6-naphthalate) (r-PET/PEN) blends by enhancing the miscibility between PET and PEN with the usage of chain extenders. This idea was novel for the recycled PET-based r-PET/PEN blends, as investigation of the effects of the chain extender usage on the properties of r-PET/PEN blends has not been studied in the literature, according to our knowledge. 1,4-Phenylene-bis-oxazoline (PBO), 1,4-phenylene-di-isocyanate (PDI), and triphenyl phosphite (TPP) were selected as chain extenders. The maximum tensile strength value was observed for the 1.0PDI sample. Moreover, PDI-based blends exhibited better Izod impact strength when compared with all other samples. The miscibility and degree of crystallinity values of all blends were discussed by means of thermal analysis. 1H-nuclear magnetic resonance (1H-NMR) analysis was carried out to determine transesterification reaction levels. According to 1H-NMR results, the increase in the level of transesterification was around 40% with the usage of PDI. The optimum loading level for selected chain extenders was determined as 1 wt.%, and PDI-based blends exhibited better properties when compared with those of the blends based on PBO and TPP at this loading level.

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