Phase morphology, thermomechanical, and crystallization behavior of uncompatibilized and PP‐g‐MAH compatibilized polypropylene/polystyrene blends

Abstract

In this article, we discuss the phase morphology, thermal, mechanical, and crystallization properties of uncompatibilized and compatibilized polypropylene/polystyrene (PP/PS) blends. It is observed that the Young's modulus increases, but other mechanical properties such as tensile strength, flexural strength, elongation at break, and impact strength decrease by blending PS to PP. The tensile strength and Young's modulus of PP/PS blends were compared with various theoretical models. The thermal stability, melting, and crystallization temperatures and percentage crystallinity of semicrystalline PP in the blends were marginally decreased by the addition of amorphous PS. The presence of maleic anhydride‐grafted polypropylene (compatibilizer) increases the phase stability of 90/10 and 80/20 blends by preventing the coalescence. Hence, finer and more uniform droplets of PS dispersed phases are observed. The compatibilizer induced some improvement in impact strength for the blends with PP matrix phase, however fluctuations in modulus, strength and ductility were observed with respect to the uncompatibilized blend. The thermal stability was not much affected by the addition of the compatibilizer for the PP rich blends but shows some decrease in the thermal stability of the blends, where PS forms the matrix. On the other hand, the % crystallinity was increased by the addition of compatibilizer, irrespective of the blend concentration. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42100.

Effect of polystyrenes with different architectures on the β‐nucleating efficiency and toughening of isotactic polypropylene

“…(a), the value of the crystallization temperature ( T c ) for pure iPP is 119.81 °C, and T c values fall around 116 °C for the iPP/PS blends, indicating that the incorporation of PS inhibits the nucleation of iPP. Different results for the influence of PS on iPP nucleation have been reported in the literature . Mucha observed that the crystallization temperature of iPP/PS blends was lower than that of pure iPP, and assumed that there was an interaction between PP and PS which inhibited the nucleation of iPP .…”

“…Parameswaranpillai et al . further argued that, in the process of cooling crystallization, the volume shrinkage of semicrystalline iPP was more serious than that of amorphous PS, which would squeeze the PS particles and result in chain diffusion between iPP and PS at the phase interface . However, Bartczak et al .…”

“…Different results for the influence of PS on iPP nucleation have been reported in the literature. [44][45][46][47][48] Mucha observed that the crystallization temperature of iPP/PS blends was lower than that of pure iPP, and assumed that there was an interaction between PP and PS which inhibited the nucleation of iPP. 44 Parameswaranpillai et al further argued that, in the process of cooling crystallization, the volume shrinkage of semicrystalline iPP was more serious than that of amorphous PS, which would squeeze the PS particles and result in chain diffusion between iPP and PS at the phase interface.…”

“…44 Parameswaranpillai et al further argued that, in the process of cooling crystallization, the volume shrinkage of semicrystalline iPP was more serious than that of amorphous PS, which would squeeze the PS particles and result in chain diffusion between iPP and PS at the phase interface. 45,46 However, Bartczak et al 47 and Wenig et al 48 found that the nucleation rate of iPP/PS blends increased with respect to PS concentration, and attributed this phenomenon to the nuclei being formed at the phase interface and then transferred to the iPP matrix. For the iPP/PS blends we prepared, the dispersed PS is surrounded by the iPP matrix since the T c value of iPP is 119.81 ∘ C from our DSC studies, while the amorphous PS is still in the rubbery state.…”

The Influence of Poly(Lactic Acid) Addition to Thermal Properties of the Blended Polypropylene for Food Packaging Materials

“…A mixture of PP with PLA is an immiscible blend because they are very different in polarity, therefore it is necessary to add a compatibilizer such as polypropylenegrafted maleic anhydride (PP-g-MAH) in order to increase the properties of its blend miscibility. Parameswaranpillai [9] and Xin [10], have used PP-gMAH as a compatibilizer for PP blending with natural fibers [9,10].…”