Direct reactive blend processing

In multiphase polymeric systems, the properties of the end products do not solely depend on the properties of the pure components, but other various parameters also have a great impact (Fig. 1). In order to emphasize these factors, the following systems are taken into consideration (I) elastomer toughened styrene system, (2) elastomer toughened polycarbonate blends, and (3) direct reactive blend processing. 

In this example of model reactive polymer processing of two immiscible blend components, as with Example 11.1, we have three characteristic process times tD,, and the time to increase the interfacial area, all affecting the RME results. This example of stacked miscible layers is appealing because of the simple and direct connection between the interfacial layer and the stress required to stretch the multilayer sample. In Example 11.1 the initially segregated samples do create with time at 270°C an interfacial layer around each PET particulate, but the torsional dynamic steady deformation torques can not be simply related to the thickness of the interfacial layer, <5/. However, the initially segregated morphology of the powder samples of Example 11.1 are more representative of real particulate blend reaction systems. 

Wool-Cellulasic Fibers. One of (he oldest fiber blends in (he textile market is (he combination of wool and cotton or wool and viscose. In a one-bath process, selected direct and acid dyes are applied at pH 4.5-5.0 at 98 ItXfC. A phenolsulfonie acid condensation prodact is added as a reserving agent, to prevent the direct dyes from dyeing the wool under acid conditions, if optimum wetfastness properties are required, fiber-reactive dyes can be applied to both fibers by use of a two-bath process. 

Copolymer formation by Reactive Compatibilization is a heterogeneous reaction taking place across a melt-phase boundary. Often this process occurs by direct reaction between chemical functionalities on some fraction of each of the two polymers. In some cases a third reactive species may be added to the blend to promote copolymer formation by one of several mechanisms. 

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