Poly(acrylonitrile-co-butadiene-co-styrene) Reinforced with Hollow Glass Microspheres: Evaluation of Extrusion Parameters and Their Effects on the Composite Properties

Abstract

Hollow glass microspheres (HGMs) filled poly(acrylonitrile-co-butadiene-co-styrene) (ABS) composites were prepared by means of a twin-screw extruder. S038 HGMs were incorporated at different percentages of 2.5, 5.0, and 7.5 wt%. The HGMs were added into the twin-screw extruder at two different feeding zones, and the effect of HGMs loading and specific feeding zone addition on the composites produced was evaluated with regard to morphological, thermal, rheological, physical, and mechanical properties. As a result, the composite density was reduced while the thermal stability, storage modulus, complex viscosity, and tensile and flexural modulus were improved when compared with the ABS matrix. The results also indicate that the addition of 5.0 wt% of HGMs at the feeding zone closer to the die maintains the integrity of the HGMs and promotes composites with higher mechanical properties and lower density when compared with the composites obtained with the addition of HGMs closer to the hopper.

Preparation and Characterization of Hollow Glass Microspheres- Reinforced Poly (acrylonitrile-co-butadiene-co-styrene) Composites

“…Furthermore, this result indicates that large-scale polymer relaxations are restrained by the presence of HGM effectively, which agrees with the HDT results. In addition, the incorporation of HGM improves the stiffness of ABS, which is consistent with the results obtained in other studies 11,13,14 .…”

“…The HGM are submitted to less shear forces when fed at this zone and therefore maintain their structure during the extrusion process. In our previous study 11 , the HGM were incorporated at the extruder feeding point and the results showed that HGM were broken due to the higher residence time at the extruder associated with higher shear forces of the twin-screw extrusion process. The addition of ABS powder along with the HGM seems to promote better incorporation of the reinforcement by the polymer matrix, however, according to Figure 2 The SEM micrograph of the composite with 5.0 wt.% of HGM and 45 wt.% of high impact ABS is shown in Figure 2(d).…”

“…SEM micrographs of the composites with 2.5, 5.0 and 7.5 wt.% of HGM with 5.0 wt.% of ABS SV-165 incorporated at the central extruder zone (Z2) are shown in Figure 2. It is possible to observe that some HGM were removed from the ABS matrix at the time of the fracture probably due to the low chemical affinity between reinforcement and matrix 11 . The ABS polarity is restricted to the acrylonitrile monomer, the remaining of its structure being of a nonpolar character, while HGM presents some polarity due to the hydroxyl groups at the microsphere surface.…”

“…Reduction a materials density, therefore its weight, without reducing its mechanical properties is one the main challenges of the automotive industries 3,11 . The density and HDT values of the composites studied are presented in Table 2.…”

“…Dynamic rheological analysis can provide information on the evolution of the polymeric materials in the melt state, which can be used to anticipate the internal structures and processing properties of polymeric materials 11,13 . Storage modulus (G') represents the elastic response of a material, which relates to the potential energy stored by the material during deformation.…”