Desenvolvimento de nanocompósitos de blendas poliméricas com matriz de poliamida 6 e argila.

Abstract

The aim of this work is to develop polymer/clay nanocomposites from polymer blends with polyamide 6 (PA6) matrix. First, the effect of polyethylene grafted with acrylic acid (PEgAA) and polyethylene grafted with maleic anhydride (PEgMA) functionalized polymers and Ethylene-Methyl Acrylate - Glycidyl Methacrylate (EG) terpolymer on PA6 and PA6/Cloisite 20A (CL20A) system. It was observed that PA6 presented higher reactivity with PA6. However, in the presence of the clay, EG terpolymer showed better result and was chosen to be used in the development of the nanocomposites. The blends and the nanocomposites were characterized by X-Ray diffraction (XRD), Thermogravimetry (TG), Dtfferential scanning calorimetry (DSC), Heat distortion temperature (HDT), Oscillatory rheometry, Mechanical properties and Scanning electron microscopy (SEM). XRD tests results indicated that the PA6/EG/CL20A and PA6/EG/PEAD/CL20A systems presented a partially exfoliated structure. TG tests showed that the PA6/CL20A and PA6/EG/CL20A systems were the CL 20A clay was premixed with PA6, showed higher thermal stability than that of PA6 and other systems. DSC results revealed the presence of a melting peak at ~ 212 • C, in the binary and ternary systems were the clay was pre-mixed with PA6, which was attributed to the y phase of PA6. The results of tensile and impact tests showed that only the PA6/EG/CL20A ternary and PA6/EG/PEAD/CL20A quaternary systems where the CL20A clay was premixed with PA6, presented balanced mechanical properties when compared to PA6. For the systems containing clay, it was observed by SEM that the clay was well dispersed in either PA6 or in the blends without the presence of clay agglomerates. The results of XRD, DSC and HDT indicated that for systems where the clay was premixed with PA6, the clay is preferably located in the PA6 phase. As for systems where the clay was premixed with the EG, the clay is preferably located in the EG phase.