Última modificación: 25-07-2016
Resumen
The study of the mechanical properties of commercial polyolefins regarding their wear behavior has become an area of great interest for many technological applications, from automotive to packaging industries. In the last decades, different studies in this field have shown that the blending of commercial polyolefins with suitable materials may enhance their final properties, such as barrier or wear properties.
The synthesis of polyolefins by employing metallocenic catalysts allow to obtain poly(propylene)s(PP) with short side chain branches by incorporating different comonomers into the reactor. These branches modify significantly their crystallinity. In addition, PP can also be blended with other materials in order to obtain composites for different purposes. By using PDMS-based polymers as additives it is possible to improve and alter the superficial, crystalline, tribological and extrusion properties of commercial polyolefins.
In this work, the tribological behavior of different metallocenic isotactic propylene homo and copolymers was studied along with their mixtures with poly(dimethylsiloxane) (PDMS) of different molar masses. It was observed that wear of different metallocenic propylene copolymers alone, depended mostly on the presence and size of lateral short chain branches. Also, wear rate was decreased as the PDMS molecular weight increased. The cristallinity degrees of the samples, as well as their thermal, morphological and rheological properties were also studied in order to infer the effect of the presence of the PDMS additives in the mixtures.