An investigation on the mechanical and dynamic rheological properties of single and hybrid filler/polypropylene composites based on talc and calcium carbonate

This paper presents the impact of accelerated aging on selected mechanical and thermal properties of isotactic polypropylene (iPP) composites filled with sedimentary hybrid natural filler-Opoka rock. The filler was used in two forms: an industrial raw material originating as a subsieve fraction natural material, and a rock calcinated at 1000 °C for production of phosphorous sorbents. Fillers were incorporated with constant amount of 5 wt % of the resulting composite, and the material was subjected to accelerated weathering tests with different exposition times. The neat polypropylene and composites with calcium carbonate as a reference filler material were used for comparison. The aim of the research was to determine the possibility of using the Opoka rock as a new hybrid filler for polypropylene, which could be an alternative to the widely used calcium carbonate and silica. The thermal, mechanical, and structural properties were evaluated by means of differential scanning calorimetry (DSC), tensile tests, scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR/ATR) prior to and after accelerated aging. As a result, it was found that the composites of polypropylene with Opoka were characterized by similar or higher functional properties and higher resistance to photodegradation compared to composites with conventional calcium carbonate. The results of measurements of mechanical properties, structural and surface changes, and the carbonyl index as a function of accelerated aging proved that Opoka was an effective ultraviolet (UV) stabilizer, significantly exceeding the reference calcium carbonate in this respect. The new hybrid filler of natural origin in the form of Opoka can therefore be used not only as a typical powder filler, but above all as a UV blocker/stabilizer, thus extending the life of polypropylene composites, especially for outdoor applications.

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Hybridization Effect of Kaolin and Calcium Carbonate on Tensile and Thermal Properties of Compatibilized Polypropylene Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.803.93 ◽

2014 ◽

Vol 803 ◽

pp. 93-98

Author(s):

M.T. Muhammad Faheem ◽

M. Muhammad Safwan ◽

A.M. Mustafa Al Bakri

Keyword(s):

Thermal Properties ◽

Calcium Carbonate ◽

Hybrid Composites ◽

Testing Machine ◽

Thermoplastic Composites ◽

Melt Mixing ◽

Tensile Testing Machine ◽

Hybrid Filler ◽

Polypropylene Composites ◽

Hybridization Effect

In this study, effect of combination between two fillers, Kaolin and Calcium Carbonate into Polypropylene (PP) composites was investigated. Hybrid thermoplastic composites from Kaolin and Calcium Carbonate were manufactured via melt mixing process involving Brabender internal mixer. Polypropylene grafted Maleic Anhydride (PP-g-MA) was also blend together with Polypropylene and both fillers during melt mixing. Single filler system composites were also introduced in this study in order to have comparison with hybrid filler system composites. Tensile, morphological and thermal properties of hybrid composites were discovered by Instron 5569 tensile testing machine, scanning electron microscopy (SEM) and thermogravimetric analyzer (TGA). Tensile test shows that additional of two fillers, kaolin and calcium carbonate could increase the strength and modulus of PP matrix. Calcium carbonate gives better strength and modulus for PP matrix compared to kaolin. However, the usage of calcium carbonate and kaolin deteriorate the elongation at break of PP matrix. The usage of two different fillers also embellish PP matrix by improve the thermal stability of the composites.

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