Polymer Solutions, Suspensions, and Emulsions

FIGURE 7.6 Typical ternary phase diaram for a polymer-polymer-common solvent system. The dotted tie lines connect composition of phases in equlibrium. 

As was illustrated in Example 7.3c, AS for the dissolution of one polymer in another is extremely small. For this reason, the true solubility of one polymer in another is relatively rare, although many more examples have come to light in recent years. When such solubility does occur, it generally results from strong interactions (e.g., a large, negative AH), most often hydrogen bonds, between the polymer pairs. Polymer-polymer miscibility has been extensively reviewed [20,21]. 

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