Effect of different compatibilisers on nanoclay dispersion, thermal stability, and burning behavior of polypropylene–nanoclay blends

Abstract

ABSTRACT:The dispersion of nanoclays in nonpolar polypropylene (PP) is difficult without the use of a small fraction (1-3%) of modified grafted PP as a compatibiliser. This work reports the effect of different graft-modified polypropylenes on the dispersion of nanoclays in PP, and thermal stability and flammability of the blends. PP has been compounded in a Brabender compounder with a selection of modified PP polymers as compatibilisers. The grafts include maleic anhydride, N-ethylmaleimide, diethylmaleate, diethyl-p-vinylbenzyl phosphonate, and acrylic acid-2-[(diethoxyphosphoryl)methylamino] ethyl ester. Films were cast from the blends by compression molding and the nanocomposite structures assessed using X-ray diffraction. Thermal characterization was performed using DSC and TGA, the burning behavior was observed using limiting oxygen index measurements, and cone calorimetry where samples were exposed to 35 kW/ m 2 external heat flux.

Influence of modified mesoporous silica SBA‐15 on the flammability of intumescent high‐density polyethylene

“…Hence, the dispersion of SBA‐15 within the PE matrix may be further decreased when IFR are present. A decreased dispersion should adversely affect the burning behavior . In that respect, it is also worth recalling that the formation of a physical barrier has a limited effect on the results obtained by UL‐94 V and LOI tests.…”

Investigation of the influence of processing conditions on the thermal, rheological and mechanical behavior of polypropylene nanocomposites

“…Despite the importance of melt intercalation, the effects of processing conditions on the material's properties are not studied very extensively [5]. Most studies deal with the MMT modification and the better dispersion of organoclay in the polymer matrix and also different compatibilizers besides PP‐ g ‐Ma were investigated [6–12]. A novel approach to prepare PP nanocomposites with OH groups as compatibilizer was first reported in 1997 [13].…”

Polypropylene fibers containing dispersed clays having improved fire performance. Part II: characterization of fibers and fabrics from PP–nanoclay blends

“…Polypropylene grafted with diethyl-p-vinylbenzyl phosphonate (DEP) with synthetic procedure described elsewhere [15].…”

“…Levels between 1-3% w/w of grafted PP along with sufficient compounding have been shown to improve the dispersion of the clay platelets in the PP matrix. In a parallel study we have studied the optimisation of nanoclay dispersion in polypropylene by observing the effect of different graft copolymeric modifications of PP [15]. It was found that diethyl-p-vinylbenzyl phosphonate (DEP) and maleic anhydride (commercially available as Polybond 3200) -grafted PP gave the best results for improving the dispersion of the functionalised clays (Cloisite 20A, Southern Clay Products, USA and Elementis Bentone 107 (E107), Elementis Specialities Inc).…”