Institute of Polymers, Composites and Biomaterials, Italian National Research Council, P.le. E. Fermi 1, 80055 Portici, Naples, Italy. Electronic address:
Published: January 2024
AI Article Synopsis
Article Abstract
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 ∙K) 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.
Foam-based wound dressing materials produced by dispersing gas phases in a polymeric material are soft, adapt to the body shape, and allow the absorption of wound exudate due to their porous structure. Most of these formulations are based on synthetic substances such as polyurethane. However, biopolymers have entered the field as a new player thanks to their biocompatible and sustainable nature.
Today, plastic plays a pervasive role in everyday life. Their improper disposal can create ongoing environmental challenges. Polyurethane (PU) is a polymer with elastomeric properties that exhibits significant adhesion and durability.
Polyurethane (PUR) soft foams release malodorous and potentially toxic compounds when exposed to oxidative conditions. Current chamber test methods cannot distinguish between pre-existing volatiles and those formed during oxidation, nor can they assess the formation rates of oxidation products. We subjected PUR soft foam to oxidative treatment in a continuous air flow at 120 °C.
Polyurethane foams (PFs) are widely used in mattresses, upholstery, and insulation, but disposal is difficult due to the disintegration time and environmental hazards of synthetic polyol. This work investigates a sustainable alternative by replacing poly(ethylene glycol) (PEG) with corn cob fibers and incorporating antibacterial silver nanoparticles (AgNPs). Corn cob fibers and sodium hydroxide-treated fibers were used to make foams, with corn cob fibers substituting PEG at 5-30 wt %.
Key Laboratory of Bio-based Polymeric Materials Technology and Application of Zhejiang Province, Laboratory of Polymers and Composites, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Zhejiang, Ningbo 315201, PR China. Electronic address:
Wound healing is a complex process and the mechanism of the tissue repair process involves many complex steps: inflammation, proliferation, and maturation. Wounds can be divided into two main categories: acute and chronic wounds. Non-healing wounds usually follow a bacterial infection.
