Surface modifcation and adhesion improvement of polyester flms

摘要

Facile surface modifcation of polyester flms was performed via chemical solutions treatment. Surface hydrolysis was carried out by means of sodium hydroxide solutions, leading to the formation of carboxylate groups. Three commercial polyester flms of 100 μm in thickness were used in this work: AryLiteTM, Mylar TM, and TeonexTM, hydrolysis time being the main modifcation parameter. FTIR-ATR analysis, topography and contact angle (CA) measurements, surface free energy (SFE) and T-Peel adhesion tests were carried out to characterize the modifed flms. A quantitative estimate of the carboxylates surface coverage as a function of treatment time was obtained through a supramolecular approach, i.e. the ionic self-assembly of a tetracationic porphyrin chromophore onto the flm surface. The surface free energy and critical surface tension of the hydrolyzed polyesters was evaluated by means of Zisman, Saito, Ber thelot and Owens-Wendt methods. It was shown that NaOH solution treatment increases roughness, polarity and surface free energy of polymers. As a result, T-Peel strengths for modifed Mylar TM and TeonexTM flms were respectively 2.2 and 1.8 times higher than that for the unmodifed flms, whereas AryLiteTM adhesion test failed.