Abstract:
［Objective］Inorganic potassium silicate coatings had comprehensive advantages suchas ultra-low volatile organic compound（VOC）emissions，low cost，weather resistance，flame retardancyand breathability. However，the poor water resistance limits their application.［Methods］High SiO2/K2O ratio potassium silicate that feature storage ability was firstly prepared by compounding low SiO2/K2O ratio potassium silicate with silica sol，further modified by potassium methylsilicate（PMS） and methyl trimethoxysilane to enhance its water resistance. Finally，the waterborne inorganic potassium silicate coating was obtained by carefully mixing styrene acrylic latex，fillers and other additives，and the adhesion，hardness，water resistance，and other properties of the coatings were characterized.［Results］The results showed that the potassium silicate with 5. 4 SiO2/K2O ratio had storage stability，and the PMS-modified samples exhibited significantly enhanced resistance to alkaline water. When the PMS content was 5% and the emulsion content was 6%，the prepared coating exhibited optimal performance，achieving Class 1 adhesion，H pencil hardness，a surface drying time of 6 minutes，and no abnormalities after 168 hours of alkaline resistance testing.［Conclusion］ This coating had good water resistance and basically met the requirements of T/CSTM 00632. 3—2022 Technical Requirement for Coatings Used in Architectural Finishing Engineering-Part 3：Inorganic Architectural Coatings System，featuring application prospects in interior wall coatings.
Key words:
high SiO2/K2O ratio potassium silicate,
inorganic coating,
waterborne coating,
water resistance
摘要： 【目的】无机硅酸钾涂料具有超低挥发性有机化合物（VOC）排放、成本低、耐候、阻燃和透气等综合优势，但耐水性差的缺陷限制了其应用。【方法】首先通过低模数硅酸钾溶液与硅溶胶复配，得到贮存稳定的高模数硅酸钾溶液，然后分别利用甲基硅酸钾（PMS）和甲基三甲氧基硅烷（Z-6070）对硅酸钾改性以增强其耐水性，最后复配苯丙乳液、填料和助剂等制备水性无机硅酸钾涂料，并对涂料的附着力、硬度、耐水性等性能进行了检测。【结果】硅酸钾溶液模数为 5. 4时其具有良好的贮存稳定性，PMS改性后的样品具有更优异的耐碱性，当 PMS的用量为 5%，苯丙乳液用量为 6%时，制备的涂料性能最优，附着力为 1级，铅笔硬度为 H，表干时间 6 min，168 h耐碱性无异常。【结论】该涂料具有较好的耐水性，基本满足 TCSTM 00632. 3—2022《建筑涂饰工程用涂料产品技术要求第 3部分：无机建筑涂料体系》的要求，在内墙涂料方面具有应用前景。
关键词:
高模数硅酸钾溶液,
无机涂料,
水性涂料,
耐水性
CLC Number: