Lightweight and insulation polylactide/poly(butyleneadipate-co-terephthalate) foam with good cushioning performance prepared by supercritical CO2
Chenxi Sun, Zhen Yu, Lijiang Jia, Xin Zhang, Yingjie Zhao, Zhenxiu Zhang
Abstract
Herein, biodegradable polylactide (PLA) foams were prepared by supercritical CO 2 . To address the foaming challenges posed caused by the low crystallization rate and the weak melt strength of PLA, the blending of PLA and poly(butyleneadipate-co-terephthalate) (PBAT) was adopted in this work, the diphenylmethane diisocyanate (MDI) was utilized to boost the compatibility and rheological features of the PLA/PBAT combination. The effects of MDI and PBAT on the crystallization and rheological of the blends were studied. In PLA/PBAT foam, the density prepared was adjustable from 0.02 to 0.025 g/cm 3 , and the heat-conductivity was a minimum of 0.028 W/(m·K). In addition, the effect of PBAT on PLA cushioning performance was studied, the PLA/PBAT foam prepared has good mechanical properties, which can be used for cushioning packaging and heat insulation. The hardness of the PLA/PBAT blend foam slowly reduced as the PBAT increased, and the elasticity gradually increased. Notably, with 10 phr of PBAT, the compressive strength of the blend foam at 25 ℃ and 60 ℃ was 57 KPa and 55 KPa, respectively. This work broadens the application prospect of PLA and has a positive impact on promoting the high-value utilization of biobased polymers. • Biodegradable PLA/PBAT foam prepared by sc-CO 2 . • The blend foam densities range from 0.02 to 0.025 g/cm 3 . • Thermal conductivity was as low as 0.028 W/(m·K). • The foam has good cushioning properties.