Changes in rigidity and depression of the melting transitions of poly(ethylene-co-vinyl acetate-co-carbon monoxide) in CO₂ have been determined with High-Pressure Torsional Braid Analysis (HP-TBA). The results show that the ambient pressure melting temperature was reduced from 56 °C to 40 °C at 73 bar, and to 30 °C at 99 bar CO₂ pressure. Foaming experiments were carried out at 30 and 40 °C at different pressure conditions along the rigidity reduction path. Foam densities in the range 0.20 g/cm³ were achievable at foaming temperatures of 30 and 40 °C, respectively. The present study shows that linking the relative rigidity or the melt strength of the polymer and the depressed melting temperature to CO₂ exposure pressure allows for rational assessments of the lower saturation pressures that would still permit foaming at a given temperature, and the upper saturation pressures beyond which foaming would not significantly lower the foam density.

已经通过高压扭转编织分析法（HP-TBA）确定了在CO _2中的聚（乙烯-乙酸乙烯酯-一氧化碳-一氧化碳）的刚性变化和熔融转变的抑制。结果表明，环境压力熔化温度在73 bar下从56°C降至40°C，在99 bar CO ₂压力下降至30°C 。沿着刚性降低路径，在不同的压力条件下于30和40°C进行了发泡实验。在30和40℃的发泡温度下分别可达到0.20g / cm ^3的泡沫密度。本研究表明，将聚合物的相对刚度或熔体强度与降低的熔体温度联系起来与CO _2有关 暴露压力允许合理评估较低的饱和压力，该较低的饱和压力仍将允许在给定温度下发泡，而较高的饱和压力不会超过该上限，发泡不会显着降低泡沫密度。