Surface modification of the Nylon 6,6 and wasted glass fiber-Nylon 6.6 coatings using atmospheric plasma treatment

Polymers tend to have low surface free energy, a significant cause of adhesion properties with other substances. Plasma treatment is an optimal method to improve surface properties. This work used a recycled glass fiber-polymer coating, and another based on Nylon 6,6. The surface modification of both layers was carried out with an atmospheric plasma treatment at different times. Chemical analysis of the plasma treated and the untreated surface were analyzed by infrared spectroscopy and X-ray diffraction. Atomic force microscopy (AFM) investigated the morphology and topography surface. The plasma treatment results improve wettability and surface free energy. The contact angle decreases for Nylon 6,6 from 68 degrees to 0 degrees and for glass fiber-polymer from 56 degrees to 18 degrees. However, the wettability remains over time in Nylon 6,6 layer, and the composite material reverts in 15 days. The high surface free energy after plasma treatment was mainly due to an increase in the polar component by inserting polar groups. The % crystallinity increases with plasma treatment due to the loss of the amorphous part of the polymer by plasma etching. AFM analysis shows an improvement in the roughness surface after treatment. These results greatly interest in enhancing adhesion with other substrates.