블록 디이소시아네이트와 표면 개질된 무기나노입자의 합성 및 응용

Abstract

In this study, we were prepared water soluble additives to improve water resistance of water borne adhesive. The water soluble additives were prepared by diisocyanate agents reacted with sodium bisulfite in co-solvent media at room temperature. The absence of the isocyanate group was confirmed by FT-IR measure, indicating that the reaction of isocyanate with sodium bisulfite high yield. The stable form of the isocyanate in water reversibly changed in 140-150 ℃ was confirmed by DSC. The water soluble additives were added into water based adhesive of DM-95 to preparing one-part adhesive. After spray coating between PP foam and artificial leather using one-part adhesive, it was dried at 150 ℃ for 30 min. Peel strength was measured by using KS M ISO 11339 method with 100 mm/min speed. Peel strength was improved after added water soluble additives than normal DM-95. In addition, the water resistance of the adhesive is remarkably improved when compared to after immersion in water for 10 hours.

In recent years, silica has been widely used as a filler for coatings and composites. In order to increase compatibility of silica, surface modification is often used. In this study, the surface modification of silica nanoparticles with a silane coupling agent was studied using supercritical carbon dioxide as a solvent. Three types of silane coupling agents were used, including 3- (trimethoxysilyl) propylmethacrylate (MPS), (3-Glycidoxypropyl) trimethoxysilane (GPS) and (3-aminopropyl) trimethoxysilane (APS). Thermogravimetric analysis was employed to estimate the ratio of the silane agent reacted on the silica surface. The silica modified with APS showed a 15% mass loss at 6 h reaction time and the loss was nearly constant after 12 h and 24 h. While a slightly increase in the amount of MPS on the silica surface from 6%, 7% to 9% corresponding to the reaction time of 6, 12, and 24 h, the ratio of GPS coated on silica surface significantly increase up to 6%, 10% and 30% when the reaction time was 6, 12, and 24 h. The increase in the GPS grafting ratio at the longer reaction times was attributed to the fact that the epoxide group of hydrolyzed-GPS could react with hydroxyl groups on the surface of the silica.