Improvement of the extrusion foaming properties of externally plasticized cellulose acetate by reactive melt mixing using a multifunctional reactive oligomer
Externally plasticized cellulose acetate was modified by reactive melt mixing with a multi-functional oligomer (chain extender). The modified compound was characterized in terms of molecular properties and viscosity. The reactive modification was applied in an extrusion foaming process using 1,3,3,3-Tetra-fluoropropene (HFO-1234ze) as blowing agent. The reactive modification in the foam extrusion process can be used to affect the rheology and thereby foaming properties of the cellulose acetate compound to optimize the cell morphology of the resulting foam sheets or boards.