Effect of organoclay and silane grafting of polyethylene on morphology, barrierity, and rheological properties of HDPE/PA6 blends

Abstract

Silane-grafted high-density polyethylene (HDPE-g-Si) was prepared by reactive extrusion. The grafted polyethylene (PE) was then melt compounded with organically modified montmorillonite and polyamide-6 (PA6) to form ternary nanocomposite. Fourier Transfer Infrared was used for investigation of grafting efficiency of specimens. Dispersion of clay in the blends and individual polymers were examined by X-ray diffraction (SAXS) and transmission electron microscopy (TEM). Scanning electron microscopy and dynamic rheology were also used for further study of microstructure along with compatibilization effect of silane grafting and adding organoclay in the blends. SAXS and TEM study showed that nanoclay was delaminated by PA6 or HDPE-g-Si chains, whereas the intercalation of neat HDPE in clay layers was negligible especially in higher level of clay. The morphological studies indicated that silane-grafted HDPE had hydrophilic characteristics and, therefore, was more compatible with PA6 than neat PE. Furthermore, in the same way adding nanoclay to this blends resulted in more uniform and finer morphology. And finally, results of oxygen and hydrocarbon permeability measurement demonstrated synergetic effect of silane grafting and presence of clay on barrierity improvement of samples.

Processing – morphology – property relationships of polyamide 6/polyethylene blend–clay nanocomposites

“…Nanocomposites based on polyethylene (PE) and polyamide (PA) blends have also been studied. In particular, the effect of the composition and of filler level was investigated [19][20][21][22][23][24]. In our previous works we presented the properties of high density polyethylene (HDPE) and polyamide 6 (PA6) blends containing an organically modified montmorillonite (OMM) [25,26].…”

Synergistic Effect of 30 B and 15 A Organoclays and Compatibilizer on Improved Barrier Properties of HDPE/PA6 Composites: Preparation and Characterization

“…The common chemical mechanism recognized for this compatibility is that a grafting chemical reaction occurred between the maleic anhydride groups of the HDPE-g-MAH molecules and the amide and terminal amino groups of PA6 at the PE-PA interface to in-situ form a PA-g-Cp copolymer. The formed copolymer then resulted in the covalent intermolecular interactions between PE and PA and the connection and compatibility between polymeric phases [18][19][20]. According to the SEM images of the HDPE/PA6 nanocomposites (Figure 2A1-A3), the presence of the Oclays caused a notable reduction in the size of the PA6 spherical particles and the improvement of the phase dispersion.…”

Preparation of Modified Silane Composite Emulsion and Its Effect on Surface Properties of Cement-Based Materials

“…The indexes of gas permeability were 0.0332, 0.0414, and 0.0305 ln/min after coating with isobutyl-triethoxysilane emulsion, compound emulsion, and TEOS, respectively, when the strength grade was C40. The permeability of concrete was somewhat reduced, but was less than 0.1 ln/min, which means it still had excellent gas permeability [30,31]. It is mainly due to the infiltration of silane emulsion into the cement-based materials, which can participate in the hydration reaction of the surface layer of the cement-based materials, but does not completely block the concrete pores or form a dense mold material on the surface of the cement-based materials.…”