摘要：
In order to improve the dirt resistance and water resistance of fireproofing coating of tunnel surface,waterborne epoxy resin was taken as adhesive,organic silicon polymer,nanometer silicon dioxide and titanium dioxide were taken as antifoulants,brucite fibre was taken as inorganic flame retardant,ammonium polyphosphate(APP)/melamine(MEL)/pentaerythrotol(PER) was taken as organic flame retardant system,the appropriate proportions of organic flame retardant system's components were determined by thermo analysis,the effects of nanometer silicon dioxide,nanometer titanium dioxide,and organic silicon against on the dirt resistance of fireproofing coating were studied by fire test,thermo-gravimetric analysis,sticky dirty resistance test and water resistance test,and the excellent new-type multifunctional fireproofing coating with dirt resistance and water resistance was developed by screening and optimization experiments of formula,fire endurance test and microscopic analysis.Analysis result shows that when themass ratio of APP,PER and MEL is 2 ∶ 1 ∶ 1,the charring temperature peak of epoxy resin decreases from 331 °C to 277 °C under the catalysis of APP on PER,and the carbon residue rate of epoxy resin increases by 10％ in the temperature range of 270 °C-800 °C.The charring peak temperature of APP-PER is lower about 66 °C than the decomposition temperature of MEL and about 100 °C than the charring temperature of epoxy resin degree,which is helpful to form expanding carbonaceous layer with good heat insulation effect.When 5 ％ organic silane or 3 ％ nanometer silica and 5 ％ nanometer titanium dioxide is added into the flame retardant system comprised of APP,PER and MEL,the fireproofing time of coating is 60 min or 80 min.When quantitative organic silane,nanometer silicon dioxide and nanometer titanium dioxide are added into the flame retardant system together,the fireproofing time of coating increases to 100 min.Then 10％ zinc stannate is added into the system,the fireproofing time of coating increases to 120 min.The increase of fireproofing time shows the significant coordination fireproofing effect of the components.The final formula of optimized intumescent fireproofing coating is that the mass ratio of waterborne epoxy resin,silane,composite flame retardant,curing agent,composite nanometer powder and zinc stannate is 40 ∶ 5 ∶ 33 ∶ 4 ∶ 8 ∶ 10,its dirt resistance grade is 1,its fireproofing time is more than 120 min,and there are no peeling and cracking phenomena after 800 h immersion.8 tabs,18 figs,25 refs.%为了提高隧道表层防火涂料的抗污性和耐水性,选用水性环氧树脂作为成膜剂,有机硅烷、纳米二氧化硅和纳米二氧化钛作为抗污剂,水镁石纤维作为无机阻燃剂,聚磷酸铵(APP)/三聚氰胺(MEL)/季戊四醇(PER)作为有机阻燃体系,用热分析法确定了有机阻燃体系各组分的合适比例,通过耐火试验、热重分析、抗黏污试验与耐水性试验,分析了纳米二氧化硅、纳米二氧化钛、有机硅烷对涂料抗污性的影响,经过配方的筛选与优化试验,综合耐火极限测试和微观分析结果,开发出抗污耐水性优良的新型多功能防火涂料.分析结果表明:APP、PER和MEL的质量比为2∶1∶1时,PER在APP的催化作用下,环氧树脂成炭温度峰值由331°C降至277°C,270°C～800°C范围内环氧树脂残炭率提高约10％;APP-PER的成炭温度峰值比MEL的分解温度低约66°C,比环氧树脂的成炭温度峰值低约100°C,有利于形成隔热效果较好的膨胀炭质层;APP、PER与MEL作为阻燃体系时,加入5％有机硅烷或加入3％纳米二氧化硅和5％纳米二氧化钛,涂料的耐火时间分别为60 min或80 min,当同时加入定量的有机硅烷、纳米二氧化硅和纳米二氧化钛时,涂料的耐火时间可延长至100 min,再加入10％锡酸锌时,涂料的耐火时间可进一步延长至120 min,表现出组分间显著的协同防火效应;最终优选的膨胀型防火涂料配方为:水性环氧树脂、有机硅烷、阻燃复合剂、固化剂、复合纳米粉、锡酸锌的质量比为40∶5∶33∶4∶8∶10,该防火涂料耐污性水平为1级,耐火极限时间超过120 min,浸水800 h后无脱落与开裂现象.
