2 experiment






2.1 preparation of dissolved limb






Mix TEOS, Siwan coupling agent, ethanol and acetoacetate in a certain proportion, slowly add a proper amount of deionized water, and then adjust the pH value of banyan liquid to about 4 with dilute hydrochloric acid, fully mix for 1-2h, and then aging for 5-6h for standby.






2.2 the preparation of the film is carried out by kw-4a sizing machine with the rotating coating method. The speed of rotation depends on the size of the element, the concentration of the coating solution and the thickness of the film. Under the action of centrifugal force, Rongye forms a uniform colloidal layer on the surface of the whole component. After the solvent on the surface evaporates, it is dried and solidified in the air blast drying oven to obtain the wear-resistant coating.






2.3 performance test






Pencil hardness test method is used for coating hardness test, and scratch test is used for adhesion test. Wear resistance test: place the resin sheet horizontally, and then place the 240 sandpaper on the coating surface, load a certain quality of silicon code on the sandpaper, pull the sandpaper at a certain speed during the test, so that the sandpaper can be evenly scratched from the coating surface, so as to show the wear resistance of the minimum silicon code with obvious scratches, as shown in Figure I. The surface morphology of the film was observed by SEM.










3 results and discussion






3.1 effect of different solvents on the surface properties of coatings


The effects of ethanol, propafenone, ethanol and acetic acid on the growth of cotyledons were studied? The effect of Kunhe solution as banyan agent on the surface properties of the coating. The results are shown in table L.






It can be seen from table 1 that when ethanol is used as the solvent alone, there are pockmarks on the surface of the coating, because the polarity of ethanol is strong, and the sol prepared is not good for the resin substrate, so there will be pockmarks. When Bingsheng and haiheke liquid containing Bingfen are used as solvent, the coating is easy to crack. There are many reasons for the cracks in the coating drying process. Generally speaking, they are related to the stress in the microzone of the sol, and there are many reasons for the stress, such as the surface tension in the evaporation process of the liquid phase, the difference of the thermal expansion coefficient of the interface, etc. because of the low boiling point and the strong volatility of propions, it is very easy to cause the cracks in the drying process of the sol due to the fast removal of solvent and water Uneven film tension leads to coating cracking. When ethanol and acetoacetate 1-quinclol solution were used as solvent, it not only improved the wettability of the sol to the resin substrate, but also inhibited the rapid volatilization of solvent and water, so that the coating could contract evenly without cracking, so the surface of the coating was smooth and flat.