以副产锌泥为原料水热合成阻燃剂硼酸锌

硼酸锌是一种绿色环保型无机阻燃剂。以工业副产锌泥为锌源、硼砂为原料，利用水热法制备硼酸锌（4ZnO·B2O3·H2O）。采用X射线衍射（XRD）、热重（TG-DTA）、扫描电镜（SEM）等分析测试手段，对制备的产品进行表征，并探讨各因素对水热合成反应的影响，建立适宜的反应条件。当水热温度为140 ℃时，锌与硼砂的物质的量比为1∶1.0，固体与液体的质量比为1∶12，水热时间为7 h以上。在此条件下，所得硼酸锌粉体的XRD谱图与4ZnO·B2O3·H2O一致，失水温度高于415 ℃。若在反应体系中添加硬脂酸钠和聚乙二醇，可得到疏水型硼酸锌样品；若添加10%硼酸锌于木粉中，400 ℃时的残碳率比纯木粉高约17%~18%，表明硼酸锌有一定的阻燃性。

Hydrothermal synthesis of flame retardant zinc borate with byproduct zinc mud as raw material

Zinc borate is a kind of green and environmental-friendly inorganic flame retardant.zinc borate（4ZnO·B2O3·H2O） had been synthesized by hydrothermal synthesis method with an industrial by-product zinc mud as zinc source and borax as raw material.The prepared product was characterized by some analytical test methods，such as X-ray diffraction（XRD）， thermal gravimetric（TG-DTA），and scanning electron microscopy（SEM），and the optimum conditions were determined by investigating the factors affecting the hydrothermal synthesis.Results of experiments showed that zinc borate can be most favorably synthesized under such conditions as follows: the hydrothermal temperature was 140 ℃，the hydrothermal time was over 7 h，the amount-of-substance ratio of zinc to borax was 1∶1.0，and the mass ratio of solid to liquid was 1∶12.The XRD pattern of the resulting zinc borate powders was consistent with that of 4ZnO·B2O3·H2O，with dehydration temperature above 415 ℃.Addition of sodium stearate and polyethylene glycol in the reaction system，the hydrophobic zinc borate samples could be obtained.If 10% zinc borate was added in wood flour，the char yield at 400 ℃ was at 17%~18% higher than that of pure wood，and that indicated zinc borate had a certain degree of flame retardancy.