Low-density polyethylene (LDPE) foams blown with CO₂ typically exhibit severe shrinkage problem and poor surface appearance, which makes them have to be prepared by using hydrocarbon as the blowing agent. In this work, we reported a facile method to prepare LDPE foams with good dimensional stability by simply controlling the linear low-density polyethylene (LLDPE) addition and the dissolved CO₂ content. The rheological evaluation and foaming behaviors showed that the LDPE/LLDPE blend with a mass ratio of 90/10 possessed better foamability than LDPE and the blends of other mass ratio did. Moreover, the presence of 10 wt% LLDPE in LDPE matrix could not only facilitate the cell nucleation and the formation of open-cell structure, but also effectively solve the shrinkage problem of LDPE/LLDPE foams blown with CO₂. The shrinkage behavior was further analyzed by numerical simulation of dimensional stability, and the simulation results agreed well with the experimental results.

用CO ₂吹制的低密度聚乙烯（LDPE）泡沫通常会出现严重的收缩问题和不良的表面外观，这使得它们必须通过使用烃作为发泡剂来制备。在这项工作中，我们报告了一种通过简单控制线性低密度聚乙烯（LLDPE）的添加量和溶解的CO ₂来制备具有良好尺寸稳定性的LDPE泡沫的简便方法内容。流变学评价和发泡行为表明，质量比为90/10的LDPE / LLDPE混合物具有比LDPE更好的发泡性，而其他质量比的混合物则具有更好的发泡性。此外，在LDPE基质中存在10wt％的LLDPE不仅可以促进泡孔成核和开孔结构的形成，而且还可以有效地解决CO ₂吹塑的LDPE / LLDPE泡沫的收缩问题。通过尺寸稳定性的数值模拟进一步分析了收缩行为，模拟结果与实验结果吻合良好。