新型硼酸酯类偶联剂的合成与表征

通过给硼原子提供外源配位电子以改善硼酸酯水解稳定性，合成了具有双键、氨基和羟基等反应活性基团的硼酸酯偶联剂。研究了原料配比、合成工艺、溶剂等对硼酸酯收率及反应速率的影响，并对硼酸酯的结构、物理性能、溶解性、水解稳定性及偶联效果等进行了表征。结果表明，合成的硼酸酯偶联剂由于具有氮-硼内配位作用，表现出优良的水解稳定性；材料的力学性能显示硼酸酯偶联剂对硼酸铝晶须具有良好的表面改性效果。

Synthesis and Characterization of a New Borate Ester as Coupling Agent

Existing coupling agents involving silane, aluminate ester, borate ester, etc are, in our opinion, not quite satisfactory in improving the mechanical properties of aluminium borate whisker/polymer composite. We present a new coupling agent involving borate ester that overcomes the above shortcoming remarkably. We synthesized, according to molecular design, as coupling agent a reactive inter molecular coordination borate ester containing allyl, amino, and hydroxy. We characterized the structure of our new borate ester with IR (infrared) spectrum. We discussed the effects of component ratio, amount of solvent, and synthetic processing on the yield and reaction rate of our new borate ester. We also investigated its hydrolytic stability, solubility, and physical properties. Our research results indicate that the hydrolytic stability of our new inter molecular coordination borate ester containing nitrogen is good as its hydrolytic time reaches 40h. We selected the optimum processing conditions for synthesizing our new borate ester through experiments. The experimentally measured mechanical properties of aluminium borate whisker/polymer composite, as shown in Fig.6, show preliminarily that our new borate ester is indeed better than existing coupling agents.