Improving the Foaming Behavior of PBAT by Graft Modification: Mechanisms, Characteristics, and Degradation.

As a biodegradable material, poly (butylene adipate-co-terephthalate) (PBAT) has important environmental significance, but its linear molecular chain structure makes it difficult to foam, and the traditional crosslinking modification will reduce its degradation performance. In this work, N-vinyl-2-pyrrolidone (NVP) was grafted to PBAT using dicumyl peroxide (DCP) as initiator, then the PBAT-g-NVP foam was prepared by supercritical N₂. The results showed that the grafting reaction improved the melt strength and foaming performance, but the degradation performance was maintained. The grafting mechanism, rheological properties, thermal properties and foaming behavior were also studied. The rheological properties showed that the melt strength of PBAT-g-NVP was significantly improved. The foaming window was widened and the cell structure became uniform. When there were 0.4 wt% DCP and 3 wt% NVP, the expansion ratio of PBAT-g-NVP foam was 10.5 and the maximum compressive stress was 253.2 kPa. In addition, the degradation degree of PBAT-g-NVP foam reached 98% in 35 d. The products prepared by this work have a wide application prospect in the field of disposable packaging or medical supplies. [ABSTRACT FROM AUTHOR]