Recyclability of In Situ Microfibrillar Poly(ethylene terephthalate)/High‐Density Polyethylene Blends

Abstract

Repetitive processing was employed to assess the recyclability of in situ microfibrillar poly(ethylene terephthalate) (PET)/high‐density polyethylene (HDPE) blends which were fabricated through a “rectangular slit die extrusion–hot stretching–quenching” process. For comparison, the conventional PET/HDPE blends were also obtained using the same processing operation but without hot stretching. The morphological observation indicated that slit die extrusion and hot stretching successfully made the dispersed PET phase deform in situ into well‐defined microfibrils. The average diameter of the microfibrils increased with the processing cycles. The rheological properties obtained from the parallel‐plate dynamic rheometer suggested that the microfibrillar blends have higher viscosity and viscoelastic moduli (storage and loss moduli) as well as better flow stability than the conventional PET/HDPE blend. More importantly, with the increase in the processing cycles, an increase in yield strength and unchanged tensile modulus were observed for in situ microfibrillar blends, while a decrease in these properties for conventional blend, indicating that the in situ microfibrillar PET/HDPE blends have promising recycling potential.magnified image

Study of PET/PP/TiO2 microfibrillar‐structured composites, Part 2: Morphology and mechanical properties

“…As noticed in Figure 2(a), the protruding TiO 2 particles severely damage the PET/PP interface, thus resulting in debonding between the fibrils and matrix. Consequently, the crack easily initiates and propagates through the polymer/fiber interface under impact load, which results in a sharp decrease in impact strength 35, 36. In addition, the damaged PET fibrils also contribute to the droplet of the impact strength.…”

Simultaneously reinforce and toughen polypropylene by in‐situ introducing polylactic acid microfibrils

“…It suggests that the viscosity ratio of PLA and iPP is variable with the increasing of mixing rotor speed. A decrease of viscosity ratio could be a favorable factor for breakup of particles . If the viscosity ratio of PLA and iPP decreases with the increasing rotor speed, the PLA particle size would decrease.…”

Recycling Polymer Blends

“…HDPE/PET blends where recycled in the presence of a stabilizer aiming to get a particular new morphology without adding other modifiers or compatibilizers (Jiang et al 2007). More in detail, PET and HDPE were first processed by extrusion with a top temperature of 270 C and then they were hot-stretched in the molten state to promote the formation of microfibrillar PET within the HDPE main phase and immediately quenched to freeze this morphology.…”