Effects of pre-treatment methods on surface properties and adhesive strength of stretched acrylic sheet

To investigate the influence and mechanism of different surface pretreatment methods on the surface properties of oriented organic glass and its bonding strength with thermoplastic polyurethane (TPU). AFM, FTIR, and contact angle measuring instruments were used to measure the surface chemical composition, roughness, and surface contact angle of oriented organic glass after acid treatment, plasma treatment, and transition layer treatment. The bonding strengths between oriented organic glass and TPU before and after pretreatment were tested by using a 90 degrees peel test. The results show that the surface roughness and polarity of oriented organic glass increase after acid treatment and plasma treatment, and the surface wettability is improved, resulting in 14% and 22% increase in bonding strength, respectively. The pre-treatment of the transition layer improves the chemical compatibility between the substrate and TPU. After treatment, the surface polarity of the oriented organic glass is similar to that of TPU, reducing the interfacial tension, and improving the interfacial bonding performance significantly. The bonding strength increases from 4.44 kN/m to 23.61 kN/m.