Foaming behavior, influencing factors

Several factors can be identified as being crucial for the foaming of immiscible polymer blends the blend morphology, the phase size of the blend constituents, the interfacial properties between the blend partners, and, last but not least, the properties of the respective blend phases such as the melt-rheological behavior, the glass transition temperature, the gas solubility, as well as the gas diffusion coefficient. Most of these factors also individually influence the melt-rheological behavior of two-phase blends. 

The behavior of proteins at interfaces influences the formation of foams and emulsions (32). Stabilization of foams and emulsions depends, to a great extent, on the formation, rheological, and mechanical properties of the interfacial film ( ). Factors which ensure optimum film properties in simple systems may retard film formation or cause destabilization in foams or emulsions (3 ) for example, many rheological properties of films are maximum in the isoelectric pH range of specific proteins, yet most proteins have minimum solubility in this pH range (34). Thus, environmental and processing factors which... 

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