Neoprene/phenolic resin adhesives - which are pressure-sensitive and heat-setting, for bonding large surface areas

摘要

The adhesives consist of neoprene and phenolic resin, pref. in approx. equal quantities, in a mutual solvent, pref. hexane. An additional solvent, e.g. acetone and MEK, is used to control the viscosity and spraying props. The adhesives are pref. applied by spraying to form a cobweb structure of fine threads of 0.0025 to 0.025 cm. dia. with free surface exposed between the threads forming leak paths. The adhesive-coated surface is then heated below the m.pt. of the adhesive to remove solvent and moisture, and to vulcanise the neoprene, while a relatively low pressure of 7-14 kp/cm2 is maintained on the joint. The adhesives are suitable for bonding large surfaces of metal, wood etc. e.g. in mfe. of building components. They give bonds of good strength with high resistance to shear.