Development Of Coatings' Hydrophilic Stain-Resistance Additives

Pollution of coatings not only seriously influences decorative effects of film coatings,but also affects special functions of functional coatings.Thereby developing the stain resistance coatings is necessary.There are various approaches to improving the stain resistance of coatings.Reaction hydrophiling agents are added in coatings to develop hydrophilic stain-resistance coatings in this paper.Hydrophilic effects of two representative silane coupling agents and their effects on anti-staining performances of coatings are first studied.The result shows that siloxy in silane coupling agent is somehow hydrophilic,which is good for improving anti-staining performances of coatings.But this can not let the coatings,anti-staining performances reach a good level because siloxy contents of coupling agents are not enough.Polyethoxysiloxanes with higher siloxy content are synthesized through part hydrolyzation and polymerization reaction by using tetraethoxysilane as raw materials.In the process of synthesis,effects of the water,catalyst and temperature on products are studied.After synthesis,products' effects on coatings' anti-contamination performances are researched.In order to solve the problem of the increment of coatings' gloss and to improve the hydrophilic rate,polyethoxysiloxanes are modified with various long-chain alcohols.In the process of modification,the reactivity of various long chain alcohols and the stability of the product are studied.Meanwhile the best alcohol is selected according to coatings' water contact angles and cleaning rates.Then the optimal ratio of alcohol and tetraethoxysilane is determined through the study on the hydrophilization rate of the polymers.Coatings with various anti-staining agent contents are prepared by adding different anti-staining agents into paint.The optimal usage of hydrophilic anti-staining additives is determined by the evaluation of hydrophilic abilities and anti-staining performances.Other performances of coatings are tested to determine whether anti-staining agents with the optimal adding usage would have effects on coatings.