Will molded-in stress effect solvent bonding?
Problems in solvent bonding acrylic-based molded articles may be encountered due to molded-in stresses. Where stresses exist, the solvent will tend to cause crazing. It is therefore extremely important that gating and part design be configured to minimize stress levels when molding the part. Methods of de-gating should be selected so the least amount of stress is experienced by the part.
Molding parameters must be closely monitored and adjusted to keep stress to a minimum. One method of minimizing stress is to run the mold as hot as possible. Some times it is necessary to anneal the parts prior to solvent bonding. Annealing can be conducted in a forced air oven at 20°F below the material's heat distortion temperature.