Composite Preparation by GASP

A small amount of clay dispersed in a polymer matrix gives better final properties. The dispersion is controlled by various interactions between filler particles and polymer chains however, it is difficult to achieve a homogeneous dispersion on a nanoscale without the pretreatment of clay surfaces, since, in many cases, the hydrophilic clay surface and hydrophobic polymer chains are incompatible. 

The GASP method aUows for a wide range of vaporizable monomers to be utiHzed in the preparation of nanocomposites. Moreover, the GASP method does not require prehomogenizing and postpolymerization stages, which are often performed during the Hquid process. The obtained polymer/clay nanocomposites 

The synthesis of polymer/inorganic compound nanocomposites, accomplished by multistep reactions in solutions, has been bothered by the serious problem of coagulating inorganic particles, espedaUy, fine metal particles in the polymer matrices [78-81]. In order to prevent coagulation, El-Shall and coworkers utilized 

Inorganic nanoparticles such as metal/semiconductors (M/SC) immobilized in polymer matrices have attracted considerable interest in recent years due to their distinct individualistic and cooperative properties [84]. Although the control of size and shape of M/SC nanoparticles has been widely investigated, the fundamental mechanism of nanostructural formation and evolution is still poorly understood. A novel cryochemical solid-state synthesis technique has been developed to produce M/SC nanocomposites [85]. This method is based on the low-temperature cocondensation of M/SC and monomer vapors, followed by the low-temperature solid-state polymerization of the cocondensates. As a result of the method of stabilizing the metal particle without requiring any specific coordination bonds between the particle surface and the polymer matrix, generated nanoparticles (Ag-nanocrystal mean size 50 A) were embedded in the polymer matrix with well-controlled shapes and a narrow size distribution [86]. 

The polymer/metal particle composites have been synthesized by utilizing fine metal surfaces as effective initiation sites for radical polymerization of vaporized vinyl monomers. On the metal surfaces, GASP of vinyl monomers is initiated and induces the formation of polymer thin-film coatings of the fine metal particles. Andou et al. demonstrated that GASP of MMA on a zero-valent iron (Fe(0)) 

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