Foaming of polymers with carbon dioxide – The year-in-review – 2019

Abstract This is a review article focused on publications that appeared in 2019 to serve as a critical assessment and summary of observations of the most recent trends in polymer foaming research with the physical blowing agent carbon dioxide. The factors that drive research along with the challenges and approaches to address them to advance the field are presented as they pertain to foaming of (1) biodegradable polymers, (2) polyurethanes, (3) commodity polymers, as well as the (4) generation of functionally gradient foams, (5) development of unique experimental systems, and (6) efforts directed on modeling. Critical perspectives are provided on how the polymer foam morphology is modulated or altered by polymer structure, polymer crystallinity, nucleating agents, or degree of curing.