六环石粉分散工艺及所制细木工板负离子释放量分析

Study on dispersion technology of hexacyclic stone powder and negative ion release of blockboard

为提高细木工板负离子释放性能,以六环石粉为研究对象,在单因素试验的基础上,采用响应曲面优化法探究分散剂质量分数、超声时间和超声温度对六环石粉分散性能的影响规律,得出预测模型及优化工艺参数,并对分散前后的六环石粉进行了表征;将分散后的六环石粉加入脲醛树脂中并采用装饰人造木皮对细木工板进行贴面处理,对其负离子释放量进行测试分析。结果表明,六环石粉最佳分散工艺为聚羧酸盐质量分数0.28%、超声温度30℃、超声时间50 min,此时吸光度为0.868,与验证结果接近,回归模型准确。扫描电镜分析结果表明,分散后的六环石粉粉体间的团聚现象明显改善;傅里叶红外光谱分析结果表明,添加六环石粉和分散剂后的脲醛树脂混合胶未产生新的官能团。负离子释放量分析发现,采用分散后六环石粉与脲醛树脂混合胶压制的细木工板负离子释放量高于分散前的,负离子释放量提高了20.9%;在6个月的时间内,采用分散后六环石粉与脲醛树脂混合胶压制的细木工板负离子释放量衰减量为30个/cm^(3),衰减率为4.1%。

In order to improve the negative ion release performance of blockboard, the dispersing effect of different dispersants on hexacyclic stone powder was investigated. Among them, polycarboxylate had the best dispersing effect. A single factor test was used to explore the dispersing agent mass ratio and ultrasonic treatment conditions to disperse the hexacyclic stone powder. On this basis, the response surface optimization method was used to explore the influence of dispersant mass ratio, ultrasonic time and ultrasonic temperature on the dispersing performance of hexacyclic stone powder and obtained the prediction model and optimized the process parameters. The hexacyclic stone powder before and after dispersion was analyzed by the scanning electron microscopy, and the mixed solution of hexacyclic stone and urea-formaldehyde resin was analyzed by the Fourier infrared spectroscopy(FT-IR). The dispersed hexacyclic stone powder was added to the urea-formaldehyde resin, and the decorative artificial veneer was used to cover the blockboard. The amount of negative ion released by the negative ion blockboard was examined. The results showed that the polycarboxylate mass ratio had the greatest influence on the dispersibility of hexacyclic stone powder. The best dispersion process for hexacyclic stone powder was the polycarboxylate mass ratio of 0.28%, ultrasonic temperature of 30 ℃, ultrasonic time of 50 min, and the absorbance under this process was 0.868, which was close to the verification results obtained by three parallel experiments, and the error was small. The verified regression model was accurate and had practical value. It solved the problem of easy agglomeration of hexacyclic stone powder and dispersion in the medium. The scanning electron microscope results showed that the agglomeration of the hexacyclic stone powder after dispersion was significantly weakened, and the hexacyclic stone powder was effectively dispersed. The FT-IR results showed that the mixed resin after adding the hexacyclic stone powder and dispersant did not produce new functional group, indicating that the hexacyclic stone powder and urea-formaldehyde resin were physically combined. The analysis of the negative ion release amount showed that the negative ion release of blockboards fabricated by the mixed glue of hexacyclic stone powder and urea-formaldehyde resin after dispersion was higher than that of the undispersed hexacyclic stone powder. When the blockboard was fabricated by the hexacyclic stone powder and urea-formaldehyde resin mixture, the negative ion release amount was increased by 20.9%. Within six months, the attenuation of negative ions release amount by blockboards fabricated with the hexacyclic stone powder after dispersion was 30 ions/cm^(3), and the attenuation rate was 4.1%.