Masterbatch compositions

The extrudate samples and the solidification experiment clearly show the importance of the melting process on the mixing quality of the extruder discharge. The cases shown here are for color masterbatches in natural or white resins, but the concept applies to any solid mixture or blend added to the hopper of an extruder. Color masterbatches were used here because it is much easier to visualize than other compositional variations or thermal gradients. 

A similar kind of synergy was investigated by Cui et al.,90 who prepared by melt blending nano-modified ATH using oxalic acid, a red phosphorus masterbatch and high impact polystyrene (HIPS). Unfortunately, the use of variable amounts of HIPS in the compositions has limited the possibility to see evidence of synergistic effects. The authors have stressed the well-developed and robust character of the char layer formed after UL-94V flame test for the composition HIPS/modified ATH/ Red phosphorus (68/20/12). The use of FTIR confirmed also that both P-O-P and P-O-C groups were present in the char. 

Special considerations chemical composition of filler surface affects nucleation of filler traces of heavy metals decrease thermal stability and cause discoloration siuface free energy of fillers determines interaction large difference in thermal properties of fillers and polymer may cause stress hydrotalcite is used as acid neutralizer with stabilizing packages anatase titanium dioxide decreases UV stability presence of transition metals (Ni, Zn, Fe, Co) affects thermal and UV stability calcium carbonate and talc were found to immobilize HALS stabilizers in PP with organic masterbatches such as ethylene diamine phosphate V-0 classification can be obtained with 20-25 wt%, at the same time tensile strength and impact strength are substantially reduced... 

JMAC antimicrobial masterbatches are described. The products are based on the controlled release of silver ions. A silver chloride/titanium dioxide composite particle releases silver ions on contact with water and then maintains an equilibrium concentration in solution, releasing more ions as required to give effective preservation. Its antibacterial performance in PP mouldings, in thin section PE, itylon, PETP and PP fibres is reported. JMAC masterbatches are available in most polymeric carriers including PE, PP, polystyrene, ABS, PETP and nylon, with typical addition rates of around 1%. 

Tables 4.28 and 4.29 show effect of a montmorillonite nanoclay employed as a masterbatch (PolyOne Nanoblend 1001) in polypropylene on polypropylene-based composite containing 50% (w/w) maple wood flour and on flexural strength and modulus of the WPC.

Types calcium stearate, microcrystals of noble metals, Safoam (proprietary composition of nucleating agent and foaming agent masterbatch in PVC), talc ... 

Many of the factors that are considered when choosing the physical form of an additive have been mentioned above. Here, "physical form" simply refers to the means by which an additive is integrated into the final product. Thus the ideal physical form of an additive might be in a precompounded pellet that consistently matches the exact resin formulation needed for a product, supplied in flexible volumes by a large resin provider or compounder. More realistically, the form might be a compounded resin with a similar composition as the formulation that is needed, but which still requires adjustment or extra additives added at the press. These additive forms might be a masterbatch or... 

Lee, S. H., Kim, M. W., BQm, S. H., and Youn, J. R. 2008. Rheological and electrical properties of polypropylene/MWCNT composites prepared with MWCNT masterbatch chips. European Polymer Journal 44 1620-1630. 

A special grade, FR-372 has been designed for PP fibre and textiles. The usual method of application is via a masterbatch containing 30-40% of flame retardant. This concentrate is then diluted in the PP to reach around 3-5% of FR-372 in the final composition. 

CORIs are used for the reactive processing, compounding of alloys and blends, color masterbatches, and fiber-reinforced composition. The quality of the... 

Fig. 17.19 Typical thermal expansion behavior of PP/elastomer/masterbatch nanocomposites during the first and second heating runs in this example, the composition is 30 wt% elastomer and 3 wt%...

Fig. 17.26 SEM images of PP/EPDM/Si02 ((80/20/3) (a and b) and PP-g-MA/EPDM/Si02 (80/20/3) (c and d) ternary composites prepared using hydrophilic silica (a and c) one-step simultaneous mixing and (b and d) two-step mixing (elastomer and the filler were mixed by means of a two-roll mill at room temperature for 10 min to get masterbatch first, and then the masterbatch was melt blended with pure PP or PP-g-MA) (Yang et al. 2007)...

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