The relative role of coalescence and interfacial tension in controlling dispersed phase size reduction during the compatibilization of polyethylene terephthalate/polypropylene blends

Abstract

The breaking thread and the sessile drop methods have been used to evaluate the interfacial tension between a polypropylene (PP) and a polyethylene‐terephthalate (PET). An excellent correlation was found between the two. The breaking thread technique was then used to evaluate the interfacial tension of these blends at various levels of a styrene‐ethylene butylene‐styrene grafted with maleic anhydride (SEBS‐g‐MA) compatibilizer. In order to evaluate the relative roles of coalescence and interfacial tension in controlling dispersed phase size reduction during compatibilization, the morphology of PP/PET 1/99 and 10/90 blends compatibilized by a SEBS‐g‐MA were studied and compared. The samples were prepared in a Brabender mixer. For the 10/90 blend, the addition of the compatibilizer leads to a typical emulsification curve, and a decrease in dispersed phase size of 3.4 times is observed. For the 1/99 blend, a 1.7 times reduction in particle size is observed. In the latter case, this decrease can only be attributed to the decrease of the interfacial tension. It is evident from these results that the drop in particle size for the 10/90 PP/PET blend after compatibilization is almost equally due to diminished coalescence and interfacial tension reduction. These results were corroborated with the interfacial tension data in the presence of the copolymer. A direct relationship between the drop in dispersed phase size for the 1/99 PP/PET blend and the interfacial tension reduction was found for this predominantly shear mixing device. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35: 2271–2280, 1997

Effect of Fiber Type and Coupling Treatment on Properties of High-Density Polyethylene/Natural Fiber Composites

“…where ΔH exp is the experimental heat of fusion or crystallization determined from DSC, ΔH is the assumed heat of fusion or crystallization of fully crystalline HDPE, taken as 276 J/g as previously reported (Lepers et al 1997), and W f is the weight fraction of HDPE in the composites. For each treatment level, three replications were tested.…”

Crystallization Behaviors of Polypropylene/Polyamide-6 Blends Modified by a Maleated Thermoplastic Elastomer

“…Such significant reduction is attributed to a decrease of the interfacial tension and the coalescence inhibition of the dispersed PA6 particles due to the formation of TPE-g-PA6 interfacial copolymer. 27 When only 6 wt % TPEg is added, the size of PA6 particles is significantly reduced with respect to the noncompatibilized blend due to the compatibilization With the further increasing concentration of TPEg, the average particle size of PA6 further decreases. This causes a portion of the smaller PA6 particles below the critical size to crystallize at the temperature lower than the usual bulk T c for PA6.…”

The role of nanoclay partitioning and fibril formation on dyeability of blend nanocomposite fibres

“…The majority of blends are intended to combine the superior physical properties of engineering polymer with excellent processability and low cost of polyolefin [8][9][10][11]. The type of morphology and the shape of disperse phase play key roles in inducing desired properties to the blend [12][13][14][15][16][17][18][19]. Estatiev and Fakirov [20] introduced a novel concept of developing microfibrillar composites (MFCs) from immiscible polymer blends.…”