Comparison between five experimental methods to evaluate interfacial tension between molten polymers

Morphology Evolution of Polymer Blends under Intense Shear During High Speed Thin-Wall Injection Molding

The morphology evolution under shear during different processing is indeed an important issue regarding the phase morphology control as well as final physical properties of immiscible polymer blends. High-speed thin wall injection molding (HSTWIM) has recently been demonstrated as an effective method to prepare alternating multilayered structure. To understand the formation mechanism better and explore possible phase morphology for different blends under HSTWIM, the relationship between the morphology evolution of polymer blends based on polypropylene (PP) under HSTWIM and some intrinsic properties of polymer blends, including viscosity ratio, interfacial tension, and melt elasticity, is systematically investigated in this study. Blends based on PP containing polyethylene (PE), ethylene vinyl alcohol copolymer (EVOH), and polylactic acid (PLA) are used as examples. Compatibilizer has also been added into respective blends to alter their interfacial interaction. It is demonstrated that dispersed phase can be deformed into a layered-like structure if interfacial tension, viscosity ratio, and melt elasticity are relatively small. While some of these values are relatively large, these dispersed droplets are not easily deformed under HSTWIM, forming ellipsoidal or fiber-like structure. The addition of a moderate amount of compatibilizer into these blends is shown to be able to reduce interfacial tension and the size of dispersed phase, thus, allowing more deformation on the dispersed phase. Such a study could provide some guidelines on phase morphology control of immiscible polymer blends under shear during various processing methods.

Morphology evolution and the tri-continuous morphology formation of a PVDF/PS/HDPE ternary blend in melt mixing

Manipulate the perfect tri-continuous structure of the PVDF/PS/HDPE system successfully and it can allow preparation for the functionalization of tri-continuous morphology!

Tailoring the impact behavior of polyamide 6 ternary blends via a hierarchical core–shell structure in situ formed in melt mixing

The hierarchical core–shell structure in PA6/HDPE-g-MA/EPDM ternary blend was firstly formed using simple melt mixing. A super toughness PA6 ternary blends with HDPE-g-MA multi-core structure was obtained.

Study on the Effects of Temperature and Compatibilizer on the Interfacial Tension of PP/PA6 and PP/PET Pairs

The interfacial tension (IFT) of Polypropylene/Polyamide6 (PP/PA6) and Polypropylene/Polyethylene terephthalate (PP/PET) pairs was evaluated as a function of temperature and Glycidyl Methacrylate grafted PP (PP-g-GMA) content, using the pendant drop method (PDM). PP-g-GMA was used as the compatibilizer in both systems. It was observed that IFT values of both systems showed a linear decrease with increasing temperature. Also, presence of a small amount of PP-g-GMA compatibilizer in the PP phase reduced the IFT of polymeric pairs dramatically, while adding more compatibilizer had no influence on IFT, due to the saturation of the interface. The saturation concentrations of GMA in the PP phase were obtained for 0.05 wt.% and 0.025 wt.% in PP/PA6 and PP/PET systems, respectively. The IFT values of compatibilized systems were reduced by 68% for PP/PA6 and 57% for PP/PET pairs compared to non-compatibilized ones.