中文摘要：

为了探究聚甲基丙烯酸甲酯（PMMA）在近玻璃化转变温度下应力松弛现象的相关规律，对其在近玻璃化转变温度处进行了压缩应力松弛实验，得到了若干组实验数据。对于聚合物在玻璃化转变温度以下的松弛过程，WLF方程无法适用，因此采用Arrhenius方程从能量的角度对其松弛过程进行分析，得到了在近玻璃化转变温度下PMMA松弛时间常数τ和温度T的关系，为PMMA在玻璃化转变温度以下松弛移动因子的确定提供了理论支持。

英文摘要：

To explore the related laws of stress relaxation phenomenon about polymethyl methacrylate （PMMA） near its glass transition temperatures, the compression stress relaxation experiments were made at temperatures near glass transition temperature,and several groups of experimental data were obtained. For the relaxation process below the polymer glass transition temperature,WLF equation can＇t be applied, so analyzed its relaxation process from the perspective of energy by using the Arrhenius equation,which obtained the relationship between relaxation time constant τ and temperature T of PMMA near its glass transition temperature, and it provided theoretical support for calculating the relaxation movement factor below the glass transition temperatures of PMMA.