关键词: 活性硅醇, 聚氨酯, 复合材料, 二氧化硅, 聚合

Abstract: Active silanol can be obtained from water glass by purification and be used as an internal crosslinking agent in the synthesis of polyurethane. Polyurethane aqueous dispersions with different amount of active silanol were investigated and analyzed by measuring their particle size,water absorption rate,contact angle,potentiodynamic polarization curves,thermogravimetry and scanning electron microscopy. The results showed that average particle size of the water dispersion reached the minimum of 28.83nm,when the amount of active silanol was 30%. With the increase of the amount of active silanol,the water absorption rate of the coating increased,but the contact angle decreased. And the potentiodynamic polarization curves showed that when the amount of active silanol was 70%,the corrosion current density of the coating was the lowest and the polarization resistance was the highest. Infrared spectroscopy and scanning electron microscopy can respectively determine that structure of the dispersions contained Si-O-Si and Si-O-C groups and the coating contained silica particles,which indicated that active silanol took part in the chain reaction in the state of inorganic particles. Besides,thermogravimetric analysis demonstrated that the introduction of active silanol significantly improved the thermal stability of the coating.

Key words: active silanol, polyurethane, composites, silica, polymerization