LOW-DENSITY MICROCELLULAR POLYSTYRENE FOA MS - THERMALLY STIMULATED LIQUID-SOLID PHASE-DECOMPOSITION

Low-density microcellular foams with an apparent density of 0.012-0.06 0 g/cm(3) and average pore size of 1-35 mu m were prepared by thermall y stimulated liquid-solid phase decomposition of the system polystyren e-benzene with predominant freezing-out of the solvent. The character of the phase decomposition stipulates the formation of fibrous anisotr opic structure. The density of foams and the pore size can be varied i n wide ranges by varying the concentration of the initial solutions an d the freezing rate. The freezing rate is a critical factor that contr ols the quality of the obtained foams; when the freezing rate is highe r than the critical value, foams with poor properties are obtained.