Separation and determination of polyurethane amine catalysts in polyether polyols by using UHPLC–Q‐TOF‐MS on a reversed‐phase/cation‐exchange mixed‐mode column

Abstract

A simple, selective, and accurate ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry method was established and validated for the efficient separation and quantification of polyurethane amine catalysts in polyether polyols. Amine catalysts were primarily separated in polyether polyol-based sample by solid-phase extraction, and further baseline separated on a reversed-phase/cation-exchange mixed-mode column (SiELC Primesep™ 200) using 0.1% trifluoroacetic acid/acetonitrile as a mobile phase in gradient elution mode at a flow rate of 0.2 mL/min. High-resolution quadrupole time-of-flight mass spectrometry analysis in electrospray ionization positive mode allowed the identification as N,N'-bis[3-(dimethylamino)propyl]urea, N-[2-(2-dimethylaminoethoxy)ethyl]-N-methyl-1,3-propanediamine, and N,N,N',N'-tetramethyldipropylenetriamine. The method was validated and presented good linearity for all the analytes in blank matrices within the concentration range of 0.20-5.0 or 0.1-2.0 μg/mL with the correlation coefficients (R ) ranging from 0.986 to 0.997. Method recovery ranged within 81-105% at all three levels (80, 100, and 120% of the original amount) with relative standard deviations of 1.0-6.2%. The limits of detection were in the range of 0.007-0.051 μg/mL. Good precision was obtained with relative standard deviation below 3.2 and 0.72% for peak area and retention time of three amines, respectively.

Determination of End-Group Functionality of Propylene Oxide-Based Polyether Polyols Recovered from Polyurethane Foams by Chemical Recycling

“…10,15,16,19,24,27 Size-exclusion chromatography (SEC) 9,10,13,16,24,27 or viscosity 9,14,19 RPs are evaluated by nuclear magnetic resonance (NMR) 10,17,20,24,27 and Fourier transform infrared spectroscopy (FTIR). [15][16][17]20 The presence of low molar mass, aminofunctionalized side products, aromatic diamines, and other impurities such as residual catalyst and reagent soluble in RPs can be assessed by NMR, 10,17,20,24,27 SEC, 9,10,13,16,24 gas chromatography, 10,12,14,28 and LC on a reversed 13,22 or mixed-mode 29 stationary phase. Despite the large number of characterization techniques used to evaluate the quality of RPs, methods to determine end-group functionality of RPs are lacking.…”

“…Characterization methods to evaluate the quality of RPs include conventional determination of hydroxyl number, acid value, and water content. ,,,,, Size-exclusion chromatography (SEC) ,,,,, or viscosity ,, is used to determine the RP chain length, while structure and purity of RPs are evaluated by nuclear magnetic resonance (NMR) ,,,, and Fourier transform infrared spectroscopy (FTIR). − , The presence of low molar mass, amino-functionalized side products, aromatic diamines, and other impurities such as residual catalyst and reagent soluble in RPs can be assessed by NMR, ,,,, SEC, ,,,, gas chromatography, ,,, and LC on a reversed , or mixed-mode stationary phase. Despite the large number of characterization techniques used to evaluate the quality of RPs, methods to determine end-group functionality of RPs are lacking.…”