Influence of surface modification on thermal, adhesive properties and impact behavior of TPU films for laminated glass

Abstract The poor adhesion of TPU films limits their extensive application in lightweight laminated glass (LLG). A simple and effective method is reported in this paper to obtain modified TPU films by silane coupling agent (SCA) treatment. The polar groups (such as urethane groups, carboxyl groups, etc.) on the surface of TPU films reacted chemically with the reactive groups of SCA. Meanwhile, hydrogen bonds were formed between the silicon hydroxyl groups generated by the hydrolysis of SCA. Therefore, the adhesivity and thermal stability of TPU films were improved. Moreover, the surface of TPU films became rough after modification, hence the interfacial bonding area between TPU film and glass increased, which furthered the bonding effect of TPU film with glass plate. Compared with unmodified TPU films, the tensile shear bond strength (TSBS) of modified TPU films increased by nearly 28%, and the initial decomposition temperature increased from 277 °C to a maximum of 295.3 °C. The impact resistance of LLG was significantly improved due to the improvement of the adhesivity of TPU film.