Review article

Structuring of polypropylene matrix in composites

Ivan ŠMIT ; Ruđer Bošković Institute, Zagreb
Matjaž DENAC ; University of Maribor, FEB Maribor, Institute of Technology, Maribor, Slovenia
Iztok ŠVAB ; ISOKON, Production and Processing of Thermoplastics, Ltd, Slovenske Konjice, Slovenia
Gregor RADONJIČ ; University of Maribor, FEB Maribor, Institute of Technology, Maribor, Slovenia
Vojko MUSIL ; University of Maribor, FEB Maribor, Institute of Technology, Maribor, Slovenia
Tanja JURKIN orcid.org/0000-0002-8973-5091 ; Ruđer Bošković Institute, Zagreb
Anđela PUSTAK ; Ruđer Bošković Institute, Zagreb

Abstract

Binary isotactic polypropylene (iPP) composites with talc and wollastonite were modified with different elastomers: poly(styrene-bbutadiene-b-styrene) (SBS), poly(styrene-b-ethylene-co-propylene) (SEP), poly(styrene-b-ethylene-co-butylene-b-styrene) (SEBS), SEBS grafted with maleic anhydride (SEBS-g-MA), ethylene/propylene/diene terpolymer (EPDM), and propylene-based metallocene (mEPR) at different content ratios and studied by different microscopic techniques (optical, SEM, TEM), wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC). Complex investigations of the structure-property relationships by comparison of ternary iPP composites with constitutive binary composites and binary blends showed that different factors affect (re)structuring of the semicrystalline polypropylene matrix during its crystallization and solidification during preparation by compression moulding. Structural investigations were focused on determination of influencing factors in crystallite and spherulite growth, phase structure of the iPP crystallites, degree of crystallinity, orientation of filler particles and iPP crystallite, structuring/spherulitization of the iPP matrix, and phase morphology of particles and polypropylene composite and constitutive blend systems. From the interplay of different factors in structuring of the iPP matrix the following influencing factors could be recognized: (i) nucleation by tiny dispersed particles of polymers and filler particles, (ii) orientation of the iPP crystallite and filler particles, (iii) migration/transferring of the iPP chains from melt islands to growing lamellae during solidification, (iv) encapsulation of dispersed/filler particles leading to core-shell morphology, (v) steric hindrance factors generated by filler and dispersed elastomer particles in the spherulitization of the iPP matrix, and (vi) possible partly co-crystallization in the iPP/propylene-based metallocene copolymer (iPP/mEPR) regions.

Keywords

core-shell morphology; crystallization; ethylene/propylene/diene rubber; orientation; phase morphology; polymer composites; polymer matrix structuring; polypropylene; propylene-based metallocene copolymers; spherulitization; styrene block copolymers; talc; wollastonite

Hrčak ID:

50522

URI

https://hrcak.srce.hr/50522

Publication date:

3.4.2010.

Article data in other languages: croatian

Visits: 4.137 *