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Effects of hard- and soft-segment composition on pyrolysis characteristics of MDI, BD, and PTMG-based polyurethane elastomers
| Content Provider | Semantic Scholar |
|---|---|
| Author | Kumagai, Shogo Motokucho, Suguru Yabuki, Ryosuke Anzai, Airi Kameda, Tomohito Watanabe, Atsushi Nakatani, Hisayuki Yoshioka, Toshiaki |
| Copyright Year | 2017 |
| Abstract | A study of the morphology changes in polyurethane elastomers (PUEs) containing different hard- and soft-segment ratios during ramped-heating pyrolysis revealed that selectivity of urethane bond cleavage is controlled by only the segment composition. Several PUEs were synthesized using 4,4′-diphenylmethane diisocyanate, 1,4-butanediol, and poly(oxytetramethylene glycol) (PTMG) to examine the influence of segment composition on pyrolysis characteristics by pyrolysis–gas chromatography/mass spectrometry, evolved gas analysis–mass spectrometry, and isoconversional kinetic studies. Soft-segment-rich PUEs tended to undergo urethane bond cleavage via a 4-membered-ring transition state, while the linkages in other compositions were selectively cleaved via a 6-membered-ring transition state. The reaction selectivity can be explained by the different conformations of the urethane bonds: in the hard-segment domains by H-bonds between urethane unit NH and CO groups, and in soft-segment-rich environments by H-bonds between urethane NH groups and PTMG O linkages. The mechanism of PTMG pyrolysis was the same for all PUEs. |
| Starting Page | 337 |
| Ending Page | 345 |
| Page Count | 9 |
| File Format | PDF HTM / HTML |
| DOI | 10.1016/j.jaap.2017.05.012 |
| Volume Number | 126 |
| Alternate Webpage(s) | http://www.frontier-lab.com/techinfo/publications/pdf/2017-05.pdf |
| Alternate Webpage(s) | https://doi.org/10.1016/j.jaap.2017.05.012 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
