Compatibility effect on the thermal degradation behaviour of polypropylene blends with polyamide 6, ethylene propylene diene copolymer and polyurethane

• Published in: Polymer degradation and stability Vol. 90; no. 3; pp. 481 - 487
• Main Authors: Roeder, J., Oliveira, R.V.B., Becker, D., Gonçalves, M.W., Soldi, V., Pires, A.T.N.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.2005; Elsevier Science
• Subjects: Applied sciences; Chemical reactions and properties; Compatibiliser; Degradation; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Polymer blends; Thermal decomposition; Compatibiliser; Thermal decomposition; Polymer blends; Property composition relationship; Propylene polymer; Thermoplastic rubber; Organic anhydride; Experimental study; Compatibilizer; Functional polymer; Heterogeneous mixture; Thermal stability; Thermal properties; Amide 6 polymer; EPDM rubber; Morphology; Aliphatic polymer; Polyurethane; Olefin polymer; Compatibility; Activation energy; Thermal degradation
• ISSN: 0141-3910; 1873-2321
• DOI: 10.1016/j.polymdegradstab.2005.04.008

The morphology and thermal behaviour of polypropylene/polyamide 6 (PP/PA6), polypropylene/copolymer ethylene propylene diene (PP/PEBAX) and polypropylene/rigid polyurethane (PP/PUR) blends compatibilised with polypropylene- graft-maleic anhydride (PP- g-MA) were studied using scanning electron microscopy and thermogravimetric analyses. The study focuses on the influence of different blends obtained by mixing a thermoplastic, thermoplastic elastomer or thermoset with PP, compatibilised with PP- g-MA. The compatibilising effect of PP- g-MA in an immiscible PP/PA6 blend induces a homogeneous dispersion due to interfacial adhesion. For the PP/PEBAX and PP/PUR binary blends studied slight changes in the morphology were observed with a continuous phase but the PEBAX or PUR domains remained in the PP matrix. The deconvolution of the TGA curve permitted an evaluation of the decomposition stage of the undiluted and blend systems. Thermal stability is slightly influenced by the position of the maximum decomposition rate temperature of the first derivative thermogravimetric curve (DTG). However, the DTG curve profile remains consistent. The activation energy of undiluted PP was in the range of 162–169 kJ mol −1 determined by the Ozawa method. The stabilized activation energy value for all blends studied above a 0.4 weight-loss fraction is discussed.