Melt mixed compatibilized polypropylene/clay nanocomposites. II. Dispersion vs. thermal properties,optical transmittance,and fracture behaviors

Compatibilized polypropylene (PP)/clay nanocomposites using two different types of maleated compatibilizers, polyolefin elastomer-grafted maleic anhydride (POE-g-MA) and PP-grafted maleic anhydride (PP-g-MA), to improve the dispersion of various amounts of commercial organoclay (Closite 20 A) were prepared via a melt-mixing technique. The optical transmittance for the POE-g-MA compatibilized nanocomposites was lower than that of PP-g-MA compatibilized cases, although POE-g-MA greatly increased the interlayer spacing of the clay compared with PP-g-MA. The optical transmittance of POE-g-MA compatibilized cases increased with increasing clay content, as a result from a preferentially POE-g-MA adsorbed onto the surface and edge of clay moiety. PP-g-MA compatibilized system conferred higher tensile strength, Young's modulus, or cutting strength through crystalline yielding effect even at the nanofracture zone of deformation, but lower tear strength than POE-g-MA compatibilized system. The current results suggested that high extent of exfoliation may not guarantee high transparency or strength varied with different deformation behaviors.