Investigation of kinetics and morphology development for polyurethane-urea extended by DMTDA

Abstract

The relationship between the reactions kinetics and morphology development during the polyurethane-urea (PUU) curing process has been investigated simultaneously by in situ Fourier transform infrared spectroscopy (FTIR). The data of the FTIR spectra showed that with the increase of conversion, the absorbance of NH bands increases and its band sites shifts to lower wavenumbers; the absorbance of free urethane carbonyl kept nearly constant at low conversion, and then decreased much because of the interaction of the formed urea links, and then changed little at high conversion owing to the diffuse control. The band sites of hydrogen bonded urea carbonyl similarly shifted to lower wavenumbers and the absorbance of the hydrogen bonded urea carbonyl, associated with the phase separation of hard segments, became stronger with buildup of hydrogen bond between urea links. The carbonyl bands available during curing process were further assigned. Both interactions, such as hydrogenised effect and phase separation, played a major role in the matrix formation of the PUU polymer.

References

1. Broyer E Macosko C W Critchfield F E et al.Curing and heat transfer in polyurethane reactionmoldingPolymer Engineering and Science 1978 18(5)382387. doi:10.1002/pen.760180509
2. Richter E B Macosko C W Kinetics of fast (RIM) urethanepolymerizationPolymer Engineering ⪼ience 1978 18(13)10121018. doi:10.1002/pen.760181308
3. Pannone M C Macosko C W Kinetics of isocyanate aminereactionsJournal of Applied Polymer Science 1987 34(7)24092432. doi:10.1002/app.1987.070340707
4. Priester R D Mcclusky J V Cortelek D I et al.In-mold rim kinetics via mid-infrared fiber opticFT-IRJournal of Reinforced Plastics andComposites 1994 13(1)6886. doi:10.1177/073168449401300105
5. Hsu T J Lee L J Reaction injection moldingof polyureas I. Kinetics studyPolymer Engineering ⪼ience 1988 28(15)955963. doi:10.1002/pen.760281504
6. Priester R D Mcclusky J V O'Neill R E et al.FT-IR-A probe into the reaction kinetics and morphologydevelopment of urethane foamsJournal ofCellular Plastics 1990 26(4)346367. doi:10.1177/0021955X9002600405
7. Li Z F Yang G H Zhao D X et al.Effect of organic tin on the morpholoyg and mechanicalproperties during polyurethane-urea curing processSpectroscopy and Spectral Analysis 2000 20(5)715717 (in Chinese)
8. Li Z F Yang G H Xu C M Effect of the crosslink density on the morphology and propertiesof reaction-injection-molding poly(urethane urea) elastomersJournal of Polymer Science Part A: Polymer Chemistry 2004 42(5)11261131. doi:10.1002/pola.11077
9. Coleman M M Lee K H Skrovanek D J et al.Hydrogen bonding in polymers 4. Infrared temperaturestudies of a simple polyurethaneMacromolecular 1986 19(8)21492157. doi:10.1021/ma00162a008
10. Li Z F Yang G H Li D H et al.The effect of temperature on the structure and propertiesof polyurethane-urea by FTIRSpectroscopyand Spectral Analysis 2000 20(3)318321 (in Chinese)