申请人:——
公开号:US20040087803A1
公开(公告)日:2004-05-06
This invention relates to the reversible protection of hydroxy-silane functional groups by acid cleavable protecting groups. The development of reversible protecting groups greatly enhances the current utility of silanes while introducing further novel applications. For instance, reversibly protected silanes are of particular value in applications where room temperature cure and/or adhesion is of value, such as coatings, high resolution imaging, caulks, adhesives, sealents, gaskets, and silicones. Reversibly protected silanes can also be beneficially used in reticulating agents, and in sizing agents, tires, and release coatings. The incorporation of reversibly protected silanes into coating resins is of particular value. The reversibly protected silane can be incorporated into the coating resin by polymerizing a monomer containing the reversibly protected silane into the resin or by post-addition into the coating formulation. The reversibly protected silane remains protected under basic conditions, such as in a coating formulation that contains a volatile base, for instance ammonium hydroxide. However, deprotection occurs under mildly acidic conditions. Thus, as a coating formulation containing a volatile base dries the volatile base evaporates and deprotection occurs. This allows for controlled room temperature crosslinking to occur with hydroxy-functionalized polymers. The present invention more specifically discloses a modified silane compound consisting of a silane having 3 or 4 acetal moieties bonded thereto.
本发明涉及通过酸可解保护基对羟基硅烷官能团进行可逆保护。可逆保护基的开发极大地增强了硅烷的当前实用性,同时引入了进一步的新应用。例如,可逆保护的硅烷在需要室温固化和/或粘附的应用中具有特殊价值,如涂料、高分辨率成像、密封胶、粘合剂、密封剂、垫片和硅烷。可逆保护的硅烷也可以有益地用于交联剂、浸渍剂、轮胎和脱模涂层。将可逆保护的硅烷纳入涂层树脂中具有特殊价值。可逆保护的硅烷可以通过将含有可逆保护的硅烷的单体聚合到树脂中或通过后加入涂料配方中来纳入涂层树脂中。在碱性条件下(例如含有挥发性碱的涂料配方中),可逆保护的硅烷保持受保护状态。然而,在温和酸性条件下脱保护。因此,当含有挥发性碱的涂料配方干燥时,挥发性碱蒸发并发生脱保护。这允许与羟基化聚合物发生可控的室温交联。本发明更具体地揭示了一种改性硅烷化合物,其由具有3或4个缩醛基团的硅烷组成。