Designing seawater-degradable polycarbonate polyurethanes through stepwise-assembled polymer architecture
Journal
Polymer Degradation and Stability
Journal Volume
252
Start Page
112278
ISSN
01413910
Date Issued
2026-10
Author(s)
Abstract
The continuous rise in atmospheric CO₂ concentrations has intensified interest in carbon capture and utilization (CCU) as a sustainable strategy to mitigate global emissions. However, developing seawater‑degradable yet mechanically robust polyurethanes from polycarbonate diols (PCDLs) remains challenging due to the intrinsic stability of carbonate linkages and the hydrophobic nature of the PCDL segment. Here, we present a stepwise-assembled molecular design strategy that incorporates hydrophilic polyethylene glycol (PEG) segments into PCDL-based polyurethanes while maintaining identical overall chemical composition. By varying the sequence of PCDL- and PEG-based prepolymer assembly through one-pot and multi-pot polymerizations, we decouple polymer architecture from monomer identity and modulate chain regularity, crystallinity, and microphase separation. stepwise-assembled architectures exhibit enhanced more organized segmental arrangements, enhanced hydrogen-bond networks, and significantly improved mechanical performance compared with the random copolymer. Water-uptake studies reveal that EO chain length dominates hydrophilicity, whereas architectural sequence governs segmental mixing and accessibility of carbonate domains. Biodegradation tests in seawater show that carbonate linkages undergo partial hydrolytic cleavage, with degradability strongly dependent on polymer sequence; PEG-NCO prepolymer architectures exhibit the highest biodegradation. This work demonstrates that stepwise-assembled synthesis enables polycarbonate polyurethanes that balance durability during use with controlled seawater degradability at end of life. By enabling temporary carbon fixation followed by environmentally compatible degradation, this strategy advances a circular-carbon approach aligned with the principles of Green Chemistry.
Subjects
Microphase separation
Polycarbonate diols (PCDLs)
Polyurethanes
Seawater biodegradation
Publisher
Elsevier Ltd
Type
journal article