| 摘要 |
<p>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.</p> |
