The effect of addition of poly(propylene‐ g ‐acrylic acid) on the morphology of poly(vinyl methylether) and isotactic polypropylene blend

The interfacial adhesion of blend of isotactic polypropylene/poly(vinyl methylether) (i‐PP/PVME) has been improved by the addition of poly(propylene‐ g ‐acrylic acid) (PP‐ g ‐AA) as a compatibilizing agent. The phase morphologies of the blends are investigated by optical microscopy (OM) and lateral force microscopy (LFM). The i‐PP/PVME (80/20) blend with no addition of PP‐ g ‐AA from extrusion process shows a coarse morphology with the dispersed domain size as large as several micrometers; After the addition of 2.5% PP‐ g ‐AA in the blends, the dispersed PVME domain size decreases greatly. The addition of 5% PP‐ g ‐AA results in a homogeneous morphology. The blending of PP‐ g ‐AA with PVME reduces the crystallization temperature of PP‐ g ‐AA, which is different from that of blending i‐PP with PVME. The increase of the interfacial adhesion is attributed to the specific intermolecular interaction between the acrylic acid group of PP‐ g ‐AA and the ether group of PVME. The specific interaction is studied by Fourier transform infrared spectroscopy. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4098–4103, 2006