热固性聚氨酯粉末物性参数的测定及应用

Determination and Application of Physical Properties of Thermosetting Polyurethane Powder

为获取热固性聚氨酯粉末离散元接触模型的关键物性参数,应用于废旧热固性塑料粉末混合再生制备的精确模拟计算。以120目的聚氨酯超细粉末为例,融合了Johnson-Kendall-Roberts(JKR)模型及其尺度变换准则,借助 MATLAB图像处理技术,利用 Minitab软件对关键物性参数:碰撞恢复系数、静摩擦因数、JKR表面能,进行了Box-Behnken试验设计,得到仿真试验的堆积角回归模型,以多次真实试验测定的堆积角均值38.45°为响应值,对回归模型进行接触参数寻优,获得关键接触参数的最佳组合为:碰撞恢复系数0.25,静摩擦因数0.69,JKR表面能 6.97 J/m 2 ,最后将仿真得到的堆积角与真实试验值进行对比验证,误差在5%以内,无显著性差异。结果表明,以堆积角为参照虚拟标定的热固性聚氨酯粉末接触参数是可行的;同时探究了接触参数应用于混合搅拌再生试验的混合效率可达到80.34%,研究成果为废旧热固性塑料再生材料的制备提供了理论依据。

In order to obtain the key physical parameters of the discrete element contact model of thermosetting polyurethane powder,it was applied to the accurate simulation calculation of the mixed regeneration preparation of waste thermosetting plastic powder.Taking the 120 mesh polyurethane ultrafine powder as an example,the Johnson-Kendall-Roberts(JKR)model and its scale transformation criteria were combined.Using MATLAB image processing technology,Minitab software was used to calculate the key physical parameters,which were collision recovery coefficient,static friction coefficient and JKR surface energy.The Box-Behnken experiment was designed to obtain the cumulative angle regression model of the simulation test.The average of the stacking angle measured by multiple real tests was 38.45°,and the contact parameters were optimized for the regression model.When the collision recovery coefficient was 0.25,the static friction coefficient was 0.69,and the JKR surface energy was 6.97 J/m 2 ,the key contact parameters could achieve the best collaboration.Finally,comparing the simulated stacking angle with the actual test value,the error was in 5%,and there was no significant difference.The results show that the contact parameters of the thermosetting polyurethane powder with virtual reference calibration are feasible.At the same time,the mixing efficiency of the contact parameters applied to the mixing and stirring regeneration test could reach 80.34%.And the research results show a theoretical basis for the preparation of waste thermosetting plastics recycling materials.