Autoadhesion of Glassy Polymers

Summary: Thick bulk films of linear amorphous polymers with different chain architecture and molecular weight were brought into contact with themselves in a lap-shear joint geometry at bonding temperatures (T) below the glass transition temperatures of their bulk (T), at a small contact pressure, in order to form autoadhesive joints. As-bonded joints were shear-fractured in tension at ambient temperature, and their lap-shear strength was measured as a function of T, bonding time and molecular weight. The kinetics of the process of the development of the lap-shear strength at T < T was investigated, and the molecular mechanisms governing this process were discussed. The quasi-equilibrium surface glass transition temperatures of the investigated polymers were estimated and compared with the corresponding values of T.