新型硅硼磷阻燃剂的合成以及在防火涂料中的应用

以9，10?二氢?9?氧杂?10?磷杂菲?10?氧化物（DOPO）、二甲氧基甲基乙烯基硅氧烷（DTTLL）和硼酸［B（OH）₃］合成了一种分子结构中含有硅硼磷的阻燃剂（SiBP）。分别用傅里叶变换红外光谱仪（FTIR）和氢核磁共振光谱仪（¹H?NMR）表征了SiBP 的化学结构。用热失重分析仪（TG）表征了SiBP的热稳定性，在氮气氛围下SiBP的起始分解温度为110 ℃，并且在氮气气氛下800 ℃的残炭率高达40 %。以硅丙乳液为基体，通过加入多聚磷酸铵（APP）为协效阻燃剂，SiBP为主阻燃剂，双季戊四醇（Di?PE），三聚氰胺（MEL），无机填料硅微粉进行复配制备一种防火涂料。利用极限氧指数测定仪（LOI），UL 94垂直燃烧测试、TG、大木板燃烧实验对其防火性能进行详细的表征和分析，利用扫描电子显微镜观察炭层燃烧后的微观和宏观形貌。通过压缩性能测试仪、电子万能试验机对炭层强度和涂料剥离强度进行表征。结果表明，当APP为10份（质量份，下同）、SiBP为20份、Di?PE为4份、MEL为8份、硅微粉为25份时，极限氧指数提高到29.2 %，UL 94达到V?0级，残炭率为38.5 %，剥离强度提高到0.325 kN/m，炭层压缩强度增加到1.4 MP，亲水性增加。

Synthesis of new silicon boron phosphorus flame retardant and its application for fire retardant coatings

A flame retardant containing phosphorus， silicon and boron in its molecular structure （SiBP） was synthesized using 9，10?dihydro?9?oxa?10?phosphine?10?oxide， dimethoxymethyl vinyl siloxane， and boric acid as raw materials， and its chemical structure was characterized using Fourier?transform infrared spectroscopy and hydrogen nuclear magnetic resonance spectroscopy （¹H?NMR）. The thermal stability of SiBP was also characterized by thermogravimetry （TG）. The SiBP exhibited an initial decomposition temperature of 110 ℃ in nitrogen atmosphere was， resulting in a residual char yield of up to 40 wt% at 800 ℃. A flame?retardant coating was prepared by using silicone acrylic lotion as a matrix， silicon powders as an inorganic filler， SiBP as a main flame retardant， and ammonium polyphosphate （APP） as a synergistic flame retardant together with dipentaerythritol （Di?PE） and melamine （MEL）. The fire?resistant performance was characterized and analyzed through limiting oxygen index （LOI）， UL 94 vertical combustion test， TG， and large board combustion test. The micro and macro morphologies of the char layer after combustion were observed using scanning electron microscope. The strength of char layer and the peel strength of coating were characterized using compression tester and electronic universal testing machine. The results indicated that when the addition amounts of APP， SiBP， Di?PE， MEL， and silicon powders were 10， 20， 8， and 25 phr， respectively， the flame?retardant coating achieved an LOI of 29.2 % along with a UL 94 V?0 classification and a carbon residue rate of 38.5 wt%， and its peel strength increased to 0.325 kN/m. In addition， the compressive strength of the char layer increased to 1.4 MPa along with an increase in hydrophilicity.