Twin‐screw extrusion compounding of polypropylene/organoclay nanocomposites modified by maleated polypropylenes

Abstract

Polypropylene/organoclay nanocomposites modified with different maleic anhydride grafted polypropylene (PPgMA) compatibilizers were compounded on a twin-screw extruder. The effectiveness of the feeding sequence and compatibilizer type toward the dispersion of organoclay into PP matrix was critically studied. The composites prepared with side feed appeared to provide better dispersion and modulus improvement over that with hopper feed. The effect of PPgMA compatibilizers, including PB3150, PB3200, PB3000, and E43, with a wide range of maleic anhydride (MA) content and molecular weight was also examined. The structure was investigated with X-ray diffraction and transmission electron microscopy. The relative complex viscosity curves also revealed a systematic trend with the extent of exfoliation and showed promise for quantifying the hybrid structure of the nanocomposites. Mechanical properties were determined by dynamical mechanical analysis and tensile and impact tests. Maleated polypropylene with low-melt flow index and moderate MA content enhanced clay dispersion and resulted in significant improvement in tensile modulus of the nanocomposites.

Melt compounding of different grades polystyrene with organoclay. Part 3: Mechanical properties

“…polyvinyl pyrrolidone, polyethylene glycol, and polyvinyl alcohol. There are some experimental studies suggesting the feasibility of the preparation of PNC from such polymers by melt compounding under selected process conditions, e.g., PP [14], poly[ethylene-co-(vinyl acetate)] (EVA) [15], PA-6 [13,16], etc. However, systematic studies of melt compounding of PNC are scarce.…”

The influence of screw configurations and feed mode on the dispersion of organoclay on PP

“…PP/MMTs are produced using many technologies, and their applications include a range of manufacturing processes at a relatively low cost [1,2] . There is much evidence that supports melting processing as the preferred production method of PP/MMT for commercial use [3][4][5][6][7] . Additionally, the literature suggests that the exfoliation and the dispersion of nanoclays in polypropylene requires the exchange of the sodium cations that are present in the nanoclay layers with the organophilic cations (dimethyl, dihydrogenated tallow, and quaternary ammonium chloride), which alters the initial interlayer spacing and improves the interaction between the clay and the PP [8,9] .…”

A simple micromechanical approach to predict mechanical behaviour of polypropylene/organoclay nanocomposites based on representative volume element (RVE)

“…Consequently, the development of PP/organoclay nanocomposites [6][7][8] has drawn close attention from the researchers and engineers. However, the incompatibility and low interactions between hydrophobic PP and hydrophilic clay become very formidable.…”

“…However, the incompatibility and low interactions between hydrophobic PP and hydrophilic clay become very formidable. Recent studies [6,8] have shown that the use of functional maleic anhydride grafted PP (MAPP) as the compatibiliser can improve the clay dispersion with more effective intercalated structures.…”