Construction of Open‐Cellular Poly( <scp>l</scp> ‐Lactic Acid)/Poly( <scp>d</scp> ‐Lactic Acid)/Poly(Tetrafluoroethylene) Foams for Oil–Water Separation Under Excellent Compressive Property and Heat Resistance

ABSTRACT Open‐cellular poly( l ‐lactic acid) (PLLA, referred to as PLA) foams show broad application in various fields, while their poor open structures and insufficient compressive properties limit their performances. In this work, poly( d ‐lactic acid) (PDLA) and poly(tetrafluoroethylene) (PTFE) were incorporated into the PLA system to help prepare foams with outstanding open cell structures, superior compressive properties and excellent heat resistance. It was demonstrated that PDLA promoted the volume expansion ratio (VER) of foams greatly, PTFE facilitated the formation of open cells, and the cell morphology displayed great differences accompanying the change of soaking time and PTFE content. After introducing 5 wt% PDLA and 0.05 wt% PTFE into the PLA system, the foams undergoing 5 min soaking time achieved a VER of 35.22 and a cell density of 1.42 × 10 10 cell/cm 3 , which presented the maximum adsorption capacity of 39.97 g/g for CCl 4 . Notably, its adsorption capacity was still 94.12% of the above value after the adsorption–desorption experiments. Furthermore, its compressive modulus increased from 0.75 to 9.36 MPa, and the adsorption capacity after heat treatment retained 88.39% of the original value. Herein, this study would propose a simple and efficient strategy for fabricating open‐cell foams with enhanced compressive property and heat resistance.