%0 Journal Article
%T Efficient recycling pathway of bio-based composite polyurethane foams via sustainable diamine.
%A Recupido F
%A Lama GC
%A Steffen S
%A Dreyer C
%A Seidlitz H
%A Russo V
%A Lavorgna M
%A De Luca Bossa F
%A Silvano S
%A Boggioni L
%A Verdolotti L
%J Ecotoxicol Environ Saf
%V 269
%N 0
%D 2024 Jan 1
%M 38128448
%F 7.129
%R 10.1016/j.ecoenv.2023.115758
%X Aminolysis is widely recognized as a valuable chemical route for depolymerizing polymeric materials containing ester, amide, or urethane functional groups, including polyurethane foams. Bio-based polyurethane foams, pristine and reinforced with 40 wt% of sustainable fillers, were depolymerized in the presence of bio-derived butane-1,4-diamine, BDA. A process comparison was made using fossil-derived ethane-1,2-diamine, EDA, by varying amine/polyurethane ratio (F/A, 1:1 and 1:0.6). The obtained depolymerized systems were analyzed by FTIR and NMR characterizations to understand the effect of both diamines on the degradation pathway. The use of bio-based BDA seemed to be more effective with respect to conventional EDA, owing to its stronger basicity (and thus higher nucleophilicity), corresponding to faster depolymerization rates. BDA-based depolymerized systems were then employed to prepare second-generation bio-based composite polyurethane foams by partial replacement of isocyanate components (20 wt%). The morphological, mechanical, and thermal conductivity properties of the second-generation polyurethane foams were evaluated. The best performances (σ10 %=71 ± 9 kPa, λ = 0.042 ± 0.015 W∙ m-1 ∙K-1) were attained by employing the lowest F/A ratio (1:0.6); this demonstrates their potential application in different sectors such as packaging or construction, fulfilling the paradigm of the circular economy.