Organoclay surface

The exchange of inorganic cations by organic surfactant ions in the clay galleries not only makes the organoclay surface compatible with monomer or polymer matrix, but also de-... 

Dzhangurazov, B. Zh. Kozlov, G. V. Mikitaev, A. K. The influence of interfacial adhesion level on nanofiller structure in nanocomposites polymer/organoclay. Surface. X-raying, Synchrotron and Neutron Studies, 2011, 7, 96-99. 

This method was first reported by Heinemann et al. [1] for the polymerization of ethylene with the catalysts depicted in Figure 3.15 in the presence of clays with different types of organic modifications. Figure 3.16 compares the ethylene uptake curves with homogeneous and clay-supported MBI catalyst. Lower activity and more stable polymerization rate were observed for the clay-supported system. As water present on the clay surface acts as a catalyst poison [71], the low polymerization activity observed for the clay-supported system was attributed to water traces remaining on the organoclay surface. 

Further the Eq. (9) allows to estimate the value (p In Fig. 8.2 the dependence j((p.j.) for nanocomposites LLDPE/MMT is adduced. As one can see, reduction at (Pjj, increasing is observed, that is, formed on organoclay surface densely packed (and, possibly, subjecting to epitaxial crystallization [9]) interfacial regions as if pull apart nanoclusters, reducing statistical segments number in them. As it follows from the Eqs. (9) and (8), these processes have the same direction, namely, nanocomposite elasticity modulus increase. 

S-SBR, and organoclay it can be assumed that the surface silanol groups of the layered silicates react with the carboxyl groups of the XNBR and, thus, direct rubber-filler bonds are formed. In this way, the high elongation properties can be explained. 

The dispersive and polar parts of the surface energies were calculated from contact angle measurements with test liquids of different surface tension and polarity, using a modified Wihelmy technique [79] Organoclay filler yF = + = 24.3 mJ m + 1.0 mJ m 2 EPDM = I = 24.2 mj... 

---