Abstract: Novel fire resistant insulating structural building elements are provided which are comprised of unitized structures such as walls, roofs, ceilings, and floors in combination with a layer of plastic foam insulation to which is in turn bonded a coating of gypsum plaster by a layer of bonding agent. The novel elements of the invention find particular utility in the rapid and economic construction of thermally insulated and fire resistant buildings. Additionally, a method is disclosed for a facile and economic way of providing thermal barrier protection for exposed plastic foam insulation in existing buildings by the application of a bonding agent and a plaster coat on said foam.

Abstract: A novel process for the preparation of polyisocyanurate spray foams is disclosed. The catalyst combination comprises (i) N,N-dimethylcyclohexylamine, and (ii) a tetra (lower-alkyl) quaternary ammonium salt of an alkanoic acid. The use of this catalyst combination in the preparation of polyisocyanurate spray foams enables the systems to be sprayed under conditions of low ambient temperature upon cold substrates and to achieve good adhesion between the foam and substrate under such conditions. The polyisocyanurate foams produced using the novel catalyst combination of the invention are characterized by having high resistance to flame and heat distortion.