Creep response of thixotropic ambient temperature cure adhesives measured by DMTA in static tension and shear

摘要: Abstract The technology for bonding in rods into timber structures repair, reinforcement and forming primary connections is now well established. An ambient temperature cure adhesive required on site overhead application thixotropic (shear thinning) characteristics are essential. At the same time bonded-in components may experience service temperatures of 50 °C or more, especially roof spaces. It commonly supposed that an with a glass transition ( Tg ) below in-service will suffer from potential creep unless it tightly cross-linked. In this paper properties three epoxy-based, adhesives investigated, which less heavily cross-linked possess values between 30 60 °C. subjected to load tension within Dynamic Mechanical Thermal Analyser used static mode step-wise increase range stress levels. A unique laminated shear specimen has been developed comprising layer sandwiched by two thin wood veneers so can be stressed shear. results demonstrate +15 °C limit, behaving as classic viscoelastic polymers above they behave like rubbers no creep. high stresses eventually fail rupture bonds. conclusion, seen combination physical chemical properties, enable them function under load.