Organoclay ternary blends

Development of Ethylene Vinyl Acetate/Natural Rubber/ Organoclay Ternary Blends... 

The solution-blending method was also employed by Srivastava et al. to prepare EPDM/ EVA/organoclay ternary nanocomposites [67,68]. EVA, with 45 wt% vinyl acetate (VA), and EPDM were blended in a 50/50wt/wt ratio with 2-8 wt% H3(Ci6)i organoclay in hot toluene... 

More recently, some authors [59] and [65] have studied the effect of ternary blend morphologies on mechanical properties. Martins [65] prepared ternary nanocomposites of PP (-t-PP-g-acrylic acid)/ EVA/organoclay (60/40/5) by different blending procedures. He showed different localization of the... 

Table 9.3 gives the tensile and impact properties of the PBT/EVA-g-MAH/ organoclay ternary nanocomposite as well as diose of PBT and PBT/EVA-g-MAH blend. ° It can be found that the impact strength of the ternary nanocomposite is in between that of the PBT and PBT/EVA-g-MAH blend. As shown in Fig. 9.8, the fine dispersion of elastic EVA-g-MAH in die continuous PBT phase is responsible for the remarkable impact strength improvement to the PBT. 

Tab e9.3 Tensileand impact properties of PBT, PBT/EVA-g-MAH blend, and PBT/ EVA-g - MAH/organoclay ternary nanocomposite (reprinted from ref. [50] with permission from VSP)... 

Chiu et al [134] also prepared polyamide 6 ternary nanocomposites with organoclay (5 wt%) and maleated polyolefin elastomer (10 wt%) as fillers. Izod impact strength of this ternary nanocomposite was 51.6 J/m, which was much higher than the binary clay nanocomposite (22.8 J/m) and neat polyamide (37.7 J/m), but significantly lower than the tough binary blend (104.8 J/m). This again ascertains the necessity to have a higher rubber content of >15 wt%... 

Figure 11.20. Variation of notched impact strength with mSEBS loading iu binary polyamide 6/mSEBS blends and ternary polyamide 6/organoclay (3wt%)/mSEBS naiiocomposites [131]...

Table 11.3. Mechanical properties of neat polyamide 66 (BO), polyamide 66/organoclay nanocomposite (95/5) (Bl), polyamide 66/SEBS-g-MA binary blend (85/15) (B2), and ternary nanocomposites, N1 to N4 [143]...

Very few papers have been published on the preparation of polymer blend nanocomposite from organoclays and poly(ethylene oxide)/poly(methyl methacrylate) (PEO/PMMA) blend by the solution blending method." In this section, we discuss how the blending sequence affects the microstructure of the ternary hybrid nanocomposites and especially the dispersion states of the organoclays in the polymer matrix. 

Unfortunately, however, the impact strength of die ternary nanocomposite is lower than that of the PBT/EVA-g-MAH blend. It should be noted, however, the uniform dispersion of the intercalated organoclay in the continuous PBT phase leads to higher tensile strength and modulus of the ternary nanocomposite compared to the PBT/EVA-g-MAH blend. It was also reported diat die thermal stability of the nanocomposite was improved in comparison to that of the PBT/ EVA-g-MAH blends, due to the clay layer structure. 

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