二水偏硼酸钙的湿法改性及表征

Wet Chemical Surface Modification and Characterization of Calcium Metaborate Dihydrate

以硼酸和氢氧化钙为原料,在常温常压下合成六水偏硼酸钙,对合成产物进行了化学成分、X射线衍射分析表征,结果表明产物为单一物相的六水偏硼酸钙(CaO.B2O3.6H2O)。在140℃下烘干3 h得到二水偏硼酸钙(CaO.B2O3.2H2O)。以硬脂酸钠、油酸为改性剂对二水偏硼酸钙进行湿法改性,考察了硬脂酸钠、油酸的用量、改性时间、改性温度等因素对二水偏硼酸钙湿法改性的影响。对改性产物进行了红外光谱、活化指数和接触角表征。结果表明:在硬脂酸钠用量为5%,二水偏硼酸钙在60℃下改性反应60 min,改性产物的活化指数可达95.27%,接触角为106.3°,改性效果明显;在油酸用量为5%,二水偏硼酸钙在90℃下改性反应90 min,改性产物的活化指数可达到95.79%。

The reaction of boric acid with calcium hydroxide afforded calcium metaborate hexahydrate at the room temperature.The obtained product was characterized by chemical analysis and XRD,the results indicated that the product is pure calcium metaborate hexahydrate.Calcium metaborate hexahydrate was treated at 140 ℃ for 3 h to afford calcium metaborate dehydrate(CaO·B2O3·2H2O).In order to make the synthesized calcium metaborate dihydrate have good compatibility with polymer materials,surfactant was used to modify the product by the wet chemical process.Sodium stearate and oleic acid were selected as modification reagents,respectively.Influences of temperature,time and adding amount of surfactant on the modification of calcium metaborate dihydrate were discussed.The preferred modification result for calcium metaborate dihydrate was achieved when 10 g calcium metaborate dihydrate was treated at 60 ℃ for 60 min by adding 0.5 g sodium stearate,while 10 g calcium metaborate dihydrate was treated at 90 ℃ for 90 min by adding 0.5 g oleic acid.The modified calcium metaborate dihydrate was evaluated by FT-IR,contact angle and activation index.The activation index of the modified calcium metaborate can reach to 95.27% and the corresponding contact angle is up to 106.3° by using sodium stearate,while the activation index of the modified calcium metaborate can reach to 95.79% by using oleic acid.