Effect of ABS/PMMA/EMA ternary blending sequence on mechanical properties and surface glossiness

Acrylonitrile-butadienestyrene (ABS)/poly(methylmethacrylate) (PMMA)/ethylene methacrylate (EMA) composites were prepared with different blending sequences. All ABS/PMMA/EMA copolymers were designed to achieve the same total chemical composition, in which ABS/PMMA was equal to 80/20 and EMA was fixed at 6 wt%. The effects of different blending sequences on the mechanical and optical properties of ABS/PMMA/EMA blends were investigated. Results indicated that the tensile strengths of ABS/PMMA/EMA blends with different blending sequences were slightly affected, whereas the Izod impact strength of blends significantly varied. The impact toughness of the blends, in which PMMA/EMA was initially blended and then combined with ABS, was approximately twice that of the other blends. This blending sequence also had surface glossiness that was superior to those of the other blends. Differential scanning calorimetry and scanning electron microscopy further revealed that blending sequence influenced the phase miscibility and dispersion of the blends, which led to different mechanical and optical properties.

Study on the effect of processing conditions on the impact strength of PP/SEBS/PC ternary blends using Taguchi experimental analysis

In this study, nine ternary blends of polypropylene (PP)/poly [styrene-b-(ethylene-co butylene)-b-styrene] tri-block copolymer (SEBS)/polycarbonate (PC) were produced at different processing conditions through twin screw extruder. Accordingly, die temperature, screw speed, and blending sequences were altered based on L9 Taguchi experimental design as indications of processing variables. Consequently, the impact strength of each produced sample is considered as the responding variable. Analyzing two important aspects, namely main and interactive effects by using Taguchi analysis, was the especial point of view in our contribution; as a result, not only was the PP/SEBS/PC ternary system studied for the first time, but the SEBS-g-MAH compatibilizer also showed sufficient effects on morphology development. It was observed that the impact strength of PP/SEBS/PC ternary blends is not affected by die temperature significantly, whereas screw speed and blending sequence have had effective impacts. Besides, the optimum processing condition, which is proportional to the highest value of impact strength, is recommended through the mentioned ternary blends. These results are also confirmed while applying image analysis on morphology micrographs.

Microstructure and properties of PET/EPDM, EPDM-g- MA/organoclay ternary hybrid nanocomposites: effect of blending sequence

Poly(ethylene terphthalate) (PET)/organomontmorilonite (OMMT)/maleic anhydride ethylene-propylene-diene rubber (EPDM-g-MA) nanocomposites were prepared via melt blending of the ingredients in a Haake Rheocord mixer. To make the hybrid composites, four different blending routes were examined: 1) preparing EPDM/EPDM-g-MA (EPMA)/organoclay nanocomposite and then blending it with PET, (S1), 2) dispersion of organoclay in PET and then blending it with EPMA, (S2), 3) blending PET with EPMA and then mixing it with organoclay, (S3), 4) blending PET, EPMA and organoclay in a single process, (S4). The microstructure of the PET/(EPMA)/organoclay ternary hybrids were characterized by X-ray diffraction (XRD) and Transmission Electron Microscopy (TEM). The result showed that the blending sequence greatly affects the dispersion of organoclay in the polymer matrix as well as the microstructure of the blends. Mechanical behavior of the blends including tensile and impact properties were also studied. Results revealed that PET/ (EPMA)/organoclay nanocomposites made by mixing sequence, S1, has the maximum tensile and impact strength among the others. This was attributed to its fine “Sea-Island” morphology and good dispersion of the organoclay in the continuous PET matrix.