One-Pot Reaction of Waste PET to Flame Retardant Polyurethane Foam, via Deep Eutectic Solvents-Based Conversion Technology

Synthesis and characterization of polyurethane flexible foams provided from PET derivatives, fly ash, and glass wastes

“…1 a and b the FT-IR analysis evidenced the characteristic vibrations of polyurethane structure for all samples filled with fly ash [ 32 ] and glass waste. The signal from 3332 cm −1 was assigned to NH stretching and the peak from 1721 cm −1 attributed to C O stretching confirmed the formation of urethane groups due to the reaction between the OH groups and NCO groups from MDI [ 32 ]. Vibrations of CH 2 , respectively CH 3 groups were registered at 2925 cm −1 and 2857 cm −1 .…”

“…A recent study [ 32 ] uses fly ash from fluidized bed combustion - a waste product that is rarely utilized in industry - as a filler in modified PUR foam; the PUR foams demonstrated better thermal stability, lower carbon levels, and improved calorific values with up to 20 wt percent of filler. Thus, our study involved two steps: i) the breakdown of PET waste coming from soft-drink bottles, and ii) the development of PUR foams composites with various contents of the filling agents.…”

Synthesis and Mechanical Performances of Polyurethane Bio-Based Adhesives Resulted from the Depolymerization of Lignocellulose Biomass

“…The signal from 3310 cm –1 was attributed to NH stretching, while the signal from 1722 cm –1 was assigned to C=O stretching, confirming the formation of urethane groups as a result of the reaction between the OH groups from component A and NCO groups from MDI (component B). 31 Vibrations of CH 2 groups were registered at 2877 cm –1 . The NCO signal from 2102 cm –1 was assigned to the terminal groups of the polymeric chain.…”

Dual Functionality of MFI Zeolite Nanosheets as a PET Depolymerization Catalyst and a Flame Retardant in Repolymerized Polyurethane

“…Subsequently, all polyols were mixed for 1 h at a temperature of 80 °C. The glycolysis reactions were then conducted under reflux conditions for 2 h at 140, 160, and 180 °C in a nitrogen atmosphere. − …”