A formulation to produce urethane linkages reacts cyclocarbonate groups with diamines. Aliphatic polyhydroxyl precursor molecules are first epoxidized. The invention does not require complete epoxidation, as it makes use of the unepoxidized hydroxyl groups of the precursor molecule. These hydroxyl groups are combined with isocyanate groups of prepolymer molecules to form urethane links. The use of prepolymers increases the networking, flexibility, and impact-resistance of the final product. The known formulations for amine hardeners also require complete carbonation of the epoxy groups to form reactive cyclocarbonate groups, which are reacted with diamines to form an amine hardener. In the proposed invention, both cyclocarbonate and epoxy groups are used to combine with the different diamine molecules by making use of the different reactivities of aliphatic, cycloaliphatic, and aromatic amine groups. This procedure not only increases the networking in the final polyurethane, it ensures that there are enough reactive amines to form the amine hardener. In addition, the resulting urethane contains hydroxyl groups which impart water-compatibility. The amine hardener can then be combined with any commercial epoxy resin to form a polyurethane that is water-compatible, non-toxic, has a low viscosity, and a high degree of penetrance into a surface, and after curing is impact-resistant, abrasion-resistant, chemical-resistant, strong, and flexible.
环
碳酸酯基团与二胺反应生成聚
氨酯连接体的配方。脂肪族多羟基前体分子首先进行环氧化。本发明不要求完全环氧化,因为它利用了前体分子中未氧化的羟基。这些羟基与预聚物分子的
异氰酸酯基团结合形成聚
氨酯链节。使用预聚物可增加最终产品的网络性、柔韧性和抗冲击性。
胺类固化剂的已知配方还要求环氧基团完全碳化以形成活性环
碳酸酯基团,环
碳酸酯基团与二胺反应形成
胺类固化剂。在本发明中,利用脂肪族、环脂族和芳香族胺基团的不同反应活性,环
碳酸酯基团和环氧基团均可与不同的二胺分子结合。这一过程不仅能增加最终聚
氨酯的网络,还能确保有足够的反应性胺来形成胺固化剂。此外,生成的聚
氨酯含有羟基,可赋予其
水相容性。然后,胺固化剂可与任何商用环氧
树脂结合,形成一种与
水相容、无毒、粘度低、表面渗透性高的聚
氨酯,固化后具有抗冲击性、耐磨性、耐
化学性、强度和柔韧性。