Procedures to Retard or Eliminate Demixing of Polymer Mixtures

3 Procedures to Retard or Eliminate Demixing of Polymer Mixtures 

The various procedures that will be discussed are listed in Table 12-5 in order to present an overview of the basic ideas. Each heading in this table is considered briefly in this section. 

Thermodynamically stable mixtures will of course form stable blends. This implies miscibility on a molecular level. It is desirable for some applications but not for others, like rubber modification of glassy polymers. 

Advantage can be taken of this enhanced stability of blends of low molecular polymers by chai n-extending or cross-linking the macromolecules in such mixtures after they have been formed or applied to a substrate. This procedure is the basis of many formulations in the coatings industry. 

Many synthetic polymers are essentially nonpolar and do not participate in specific interactions like acid-base reactions, hydrogen-bonding, or dipole-dipole interactions. In that case, intermolecular interactions arc of the van der Waals type 

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