Effects of filler treatments on the mechanical, flow, thermal, and morphological properties of talc and calcium carbonate filled polypropylene hybrid composites

Abstract

ABSTRACT:Commercially available neoalkoxy titanate (Lica 12) and organosilane (3-aminopropyltriethoxysilane) coupling agents were used to treat talc and calcium carbonate (CaCO 3 ) to compare their effects with those of untreated fillers upon their incorporation into polypropylene (PP). Commercial stearic acid treated CaCO 3 was also used to widen the scope of the study. Single-filler PP composites (containing either talc or CaCO 3 ) and hybrid-filler composites (containing a mixture of talc and CaCO 3 ) were compounded on a twin-screw extruder and subsequently injection-molded into dumbbells. The silane and titanate treatments dramatically increased the elongation at break for both the single-filler and hybrid-filler composites, whereas stearic acid did not. There was also a moderate improvement in the impact strength of the composites, particularly those treated with Lica 12. The hybrid composites, through the synergistic coalescence of positive characteristics from talc and CaCO 3 , had exceptionally good impact properties, more so with the aid of the coupling agents. For example, the impact strength value of a Lica 12 treated hybrid composite was the greatest for all the composites studied, overshadowing the superiority of the CaCO 3 -filled PP composites, which predominantly had the highest impact properties. Further investigations of the thermal and morphological properties were also conducted to facilitate the determination of the coupling mechanisms and their interesting effects on the hybrid composites.

Filler treatment effects on the weathering of talc-, CaCO3- and kaolin-filled polypropylene hybrid composites

“…This is in contrast to the claims of some researchers who have observed additional reinforcing effects upon filler treatment [14,15]. Filler 'over-treatment' and/or post-treatment particle aggregation has been thought to be the main factors that have caused this weakening [21]. It should be noted that the amount of coupling agents used in this study was determined merely from the recommended dosage or formulation from the supplier.…”

Sustainable Carbonaceous Biofiller from Miscanthus: Size Reduction, Characterization, and Potential Bio-composites Applications

“…The practice of using fillers to improve the stiffness of plastics is common in the automotive, packaging, and other industries, with a notable example being talc reinforced polypropylene composite (Leong et al 2005). A plastic car part, for example, can contain the following basic components: a polypropylene matrix, a filler such as talc, coupling agents, and other additives (Dellock et al 2014;Mohanty et al 2015a).…”

Review of titanate coupling agents and their application for dental composite fabrication

“…The impact strength value of a LICA 12-treated hybrid composite was the highest for all the composites studied. Treatment with LICA 12 can induce good filler orientation, dispersion, and interaction with the PP matrix 59,67) . Coupling agents, such as LICA 09, LICA 01, and 1:1 mixture of LICA 12 and LICA 01, have been used in blends of PP/highdensity polyethylene (HDPE) (80/20 weight ratio) with a filler percentage of up to 30%.…”

“…Numerous studies indicate that TCAs provide good interfacial bonding, improve mechanical properties, enhance homogeneous filler dispersion, and modify the rheological behavior of composites 2,9,45,46,[56][57][58][59][60] . Thus, titanate adhesion promoters allow higher filler loading of particulate matter to either improve the properties or decrease the cost of the system without adversely affecting its viscosity.…”