环戊烷发泡硬质聚氨酯泡沫长期导热系数预测

本文以环戊烷发泡硬质聚氨酯泡沫为研究对象，采用薄片室温老化原理连续测量两种密度样品165天长期导热系数，发现导热系数的升高呈现2个阶段。通过对所得曲线进行函数拟合发现导热系数变化符合对数关系，对数方程求解初步得到25年后50mm制品的导热系数。考虑到制样过程中无法避免样品表面发生开孔，最后对函数计算得到的数据进行修正，修正结果显示两种密度样品的长期导热系数均不超过0.029 W(m•K)-1。

Long-Term Thermal Conductivity Prediction on Rigid Polyurethane Foam Blown with Cyclopentane

Thermal conductivities are tested periodically on two different density rigid polyurethane foams blown with cyclopentane. By cutting products into thin slices and after aging 165 days in room temperature, the rising curves display two different ascending steps during test period and they are proved to be true of logarithmic relationship by function fitting. Finally the values obtained from logarithmic function need to be corrected by subtracting surface cell size destroyed in cutting. The results indicate that thermal conductivity of 50mm thick product will not exceed 0.029 W(m•K)-1 after using 25 years in practice.