Reactively processed blends

Unlike incompatible heterogeneous blends of elastomer-elastomer, elastomer-plastic, and plastic-plastic, the reactively processed heterogeneous blends are expected to develop a variable extent of chemical interaction. For this reason the material properties, interfacial properties, and phase morphology of reactively processed blends would differ significantly from heterogeneous mixtures. 

In dealing with the reactive processing (blending) of multicomponent immiscible systems we must, however, also consider chemical reaction rates. Thus, we have to... 

Keywords compatibilization, functionalization, reactive processing, blends, copolymer crosslinking, in-situ formed copolymers, low molecular weight compatibilizers, miscibility. 

Inoue, T. and Marechal, P. (1997) Reactive processing of polymer blends polymer-polymer interface aspects, in Processing of Polymers, ed. Meijer, H.F..H. Materials. Science and Technology, A Comprehensive Treatment, eds. Cahn, R.W., Haasen, P. and Kramer, E.J. (VCH, Weinheim) p. 429. 

Id. Thus, it is expected that in the modified PRP-EVA blend, probably due to interface modification by reactive processing, a transesterification between the pendant MAH group in MAH-PP, and acetate groups in the EVA elastomer, as predicted in reaction Scheme 1, the dispersed rubber particles become more efficient in craze initiation. 

Bhowmick A.K., Chiba T., and Inoue T., Reactive processing of rubber-plastic blend Role of a chemical compatibilizer, J. Appl. Polym. Sci., 50, 2055, 1993. 

Stewart, M. E., Cox, A. J., and Naylor, D. M Reactive processing of poly(ethylene 2,5-naphthalene dicarboxylate)/poly(ethylene terephthalate) blends, Polymer, 34, 4060-4067 (1993). 

Keywords Dynamic vulcanization Polymer blends and alloys Reactive processing Thermoplastic elastomers Thermoplastic vulcanizates... 

From a plastics industry point of view, combining the various compounding, reactive processing and blending operations with the finished product fabrication operation, in a single line and under one roof, holds the potential for the product fabricator to become the... 

The conceptual breakdown in Fig. 1.9 (27) simply indicates the fact that in compounding, blending, and reactive processing, the base polymer(s) undergo two thermomechanical elementary-step experiences, and that the product of the first are value-added and microstructured pellets, while the second is used primarily for fabricating finished products. The important elementary steps for each experience, and the physical mechanisms that affect them, are different, because of the different objectives in each. 

The success of RIM has spurred interest in other means of reactive processing. Reactive extrusion and reactive blending are two related processes with interesting potential. Reactive extrusion refers to processes in which... 

In the blends discussed above, the interaction among the components and the compatibilizing agent is purely physical. However, to extend the range of possibilities for optimized blends preparation, reactive processing, where covalent chemical bonds are created between the partners, offers great potential. 

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