Authors Pompe, G. ; Pötschke, P. ; Pionteck, J.
Title Reactive Melt Blending of Modified Polyamide and Polypropylene: Assessment of Compatibilization by Fractionated Crystallization and Blend Morphology
Date 10.10.2002
Number 9851
Abstract The melting and crystallization behavior of nonreactive and reactive melt-mixed blends of polypropylene and carboxylic-modified polyamide (mPA) as the dispersed phase was investigated. It was found that the size of the mPA particles decreases and the crystallization behavior of the mPA particles changes in dependence on the mixing time of the blends with oxazoline-modified PP (mPP). This indicates that an <I>in situ</I> reaction occurs between the oxazoline groups of mPP and the carboxylic acid groups of mPA, resulting in a compatibilizing effect. In blends with mPP, the crystallization of the dispersed mPA phase splits into two steps. Below a critical particle size, the mPA does not crystallize at temperatures typical for bulk crystallization. These finely dispersed mPA particles crystallize coincidently with the PP phase, and this part increases with increasing mixing time. Analysis of the crystallization heat of both steps in connection with the particle volume distribution permits the estimation of the critical particle size to be <IMGSRC="/giflibrary/12/le.gif"BORDER="0">4 <IMGSRC="/giflibrary/12/mu.gif"BORDER="0"ALIGN="ABSBOTTOM">m. These investigations showed that the effect of fractionated crystallization can be used to follow the morphology development and to evaluate the efficiency of compatibilizing interfacial reactions during processing. &copy; 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3445-3453, 2002
Publisher Journal of Applied Polymer Science
Citation Journal of Applied Polymer Science 86 (2002) 3445-3453

Back to list