سلام.کسی میدونه مفهوم exfoliated و intercalated در متن زیر چی میشه؟
In situ polymerization is one method used to prepare exfoliated and intercalated polymer/clay nanocomposites. Generally, in situ polymerization consists of two stages: (i) mixing of the polymer precursor or monomer and the clay; and (ii) in situ polymerization in the presence of clay. In situ polymerization is understood to be responsible for the exfoliation and intercalation of clay in the polymer matrix . The viscosity of the polymer/clay dispersions is important for the in situ formation of polymer nanocomposites. Processing conditions such as mixing temperature and time, shearing speed, molecular weight of prepolymer and incorporation of nano llers are all important factors which in uence the ow nature of the mixture .A lower viscosity means a better ow ability and more homogeneous mixing .Furthermore, low viscosity is very helpful in removing bubbles before any chemi-cal reactions, which is a key step in polymer preparation, especially in the prepara-tion of polyurethane ( PU ) nanocomposites. Re ecting their widespread application ,a variety of intercalated and exfoliated PU/clay nanocomposites have been pro-duced to date. The rheological behavior of PU nanocomposites in solution state has been widely discussed.
In situ polymerization is one method used to prepare exfoliated and intercalated polymer/clay nanocomposites. Generally, in situ polymerization consists of two stages: (i) mixing of the polymer precursor or monomer and the clay; and (ii) in situ polymerization in the presence of clay. In situ polymerization is understood to be responsible for the exfoliation and intercalation of clay in the polymer matrix . The viscosity of the polymer/clay dispersions is important for the in situ formation of polymer nanocomposites. Processing conditions such as mixing temperature and time, shearing speed, molecular weight of prepolymer and incorporation of nano llers are all important factors which in uence the ow nature of the mixture .A lower viscosity means a better ow ability and more homogeneous mixing .Furthermore, low viscosity is very helpful in removing bubbles before any chemi-cal reactions, which is a key step in polymer preparation, especially in the prepara-tion of polyurethane ( PU ) nanocomposites. Re ecting their widespread application ,a variety of intercalated and exfoliated PU/clay nanocomposites have been pro-duced to date. The rheological behavior of PU nanocomposites in solution state has been widely discussed.