Polymer materials, such as extruded polystyrene (XPS), polyurethane (PU) and polystyrene (EPS), are extensively used as thermal insulators in cold regions to protect the engineering from frost damage. However, the performance degradation caused by freeze-thaw cycles (FTC) of polymer material has not been fully quantified. To fill this gap, a series of experiments were carried out by taking XPS board as the test material. After the XPS board was subjected to hundreds of FTC, the volumetric water absorption, thermal conductivity, uniaxial compressive strength and Young's modulus as well as creep strain were measured and analyzed. The results demonstrate that the volumetric water absorption and thermal conductivity change slightly with the FTC. After 400 times of FTC, the volumetric water absorption increased within only 0.1% and the thermal conductivity decreased within 9 × 10⁻⁴ W⋅(m⋅K)⁻¹. Additionally, the uniaxial compressive strength and Young's modulus decrease with the increasing of FTC, and the effect of FTC on Young's modulus is mainly concentrated in the first 50 times. The creep behavior of XPS board belongs to decay creep and the exponential function can describe the creep process well. The results obtained in this study may help us to understand the degradation of XPS board and provide references for the design of controlling engineering damages caused by FTC in cold regions.

聚合物材料，例如挤塑聚苯乙烯（XPS），聚氨酯（PU）和聚苯乙烯（EPS），在寒冷地区被广泛用作隔热材料，以保护工程免受霜冻损害。但是，由聚合物材料的冻融循环（FTC）引起的性能下降尚未完全量化。为了填补这一空白，以XPS板作为测试材料进行了一系列实验。对XPS板进行数百次FTC处理后，测量并分析了其体积吸水率，导热系数，单轴抗压强度，杨氏模量以及蠕变应变。结果表明，体积吸水率和导热系数随FTC的变化而略有变化。经过FTC的400倍后，体积吸水率仅增加了0。^-4  W⋅（m⋅K） ^-1。另外，单轴抗压强度和杨氏模量随着FTC的增加而降低，FTC对杨氏模量的影响主要集中在前50倍。XPS板的蠕变行为属于衰减蠕变，其指数函数可以很好地描述蠕变过程。这项研究获得的结果可能有助于我们了解XPS板的退化情况，并为控制寒冷地区FTC引起的工程损坏的设计提供参考。