Model MDI/butanediol polyurethanes: Molecular structure, morphology, physical and mechanical properties

Christenson, C. P.; Harthcock, M. A.; Meadows, M. D.; Spell, H. L.; Howard, W. L.; Creswick, Michael; Guerra, Rodrigo; Turner, Richard

doi:10.1002/polb.1986.090240703

Cited by 150 publications

(96 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In all the PUs, sharp bands appearing between 3308 and 3363 cm 21 are due to the presence of hydrogen-bonded NÀ ÀH groups. 19 However, the hydrogen-bonded carbonyl bands 20 of the urethane merge with the imine bands appearing between 1664 and 1728 cm 21 . NMR analysis also confirms the disappearance of À ÀOH and À ÀNCO groups and the formation of the urethane polymer chain.…”

Section: Solubilitymentioning

confidence: 98%

Synthesis and characterization of novel Schiff base polyurethanes

Raghu

Gadaginamath

Jeong

et al. 2009

J of Applied Polymer Sci

View full text Add to dashboard Cite

Eight different types of novel polyurethanes (PUs) were synthesized through the polyaddition reaction of 4,4 0 -(ethane-1,2-diylidenedinitrilo)diphenol and 4,4 0 -(pentane-1,5-diylidenedinitrilo)diphenol with four different diisocyanates: 4,4 0 -diphenylmethane diisocyanate, toluene 2,4-diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate. The resulting PUs were soluble in polar, aprotic solvents. Structures of the diols and PUs were established with ultraviolet-visible, fluorescence, Fourier transform infrared (FTIR), 1 H-NMR, and 13 C-NMR spectroscopy data. FTIR and NMR spectral data indicated the disappearance of both hydroxyl and isocyanate groups in the PUs. The thermal properties were investigated with thermogravimetry and differential scanning calorimetry. The weight losses, glass transitions, onset temperatures, and crystalline melting temperatures were measured. All the PUs exhibited semicrystalline and amorphous morphologies, as indicated by X-ray diffraction.

show abstract

Section: Solubilitymentioning

confidence: 98%

Synthesis and characterization of novel Schiff base polyurethanes

Raghu

Gadaginamath

Jeong

et al. 2009

J of Applied Polymer Sci

View full text Add to dashboard Cite

show abstract

“…The absorption bands at about 3290 and 3190 cm Ϫ1 are assigned to the NOH stretching vibration. Several groups [22][23][24] proved that the splitting of the bonded NOH band was related to different acceptors with which the NOH groups were hydrogen bonded, and the bands at 3325 and 3260 cm Ϫ1 were assigned to NOH groups bonded with carbonyl (in hard segments) and ether oxygen (in polyether soft segments) in the PU system, respectively. Here the bands at 3290 cm Ϫ1 should be assigned to NOH bonds, mainly with ether oxygen (in PEG soft segments).…”

mentioning

confidence: 99%

Study on synthesis and thermal properties of polyurethane–imide copolymers with multiple hard segments

Liu

2002

J of Applied Polymer Sci

View full text Add to dashboard Cite

Different multiple hard segment polyurethane-imide copolymers (MHPUI) were synthesized and characterized. FTIR spectroscopy confirmed the characteristic absorption of the MHPUI copolymer. The difference in the imide group FTIR absorption bands in different MH segment PUI copolymers was found in this study and was explained by the different MH segment types, hard segment contents, and hard segment rigidity with different interactions of the molecular chains. The hard segment interaction in MHPUI with an increase of the structure rigidity of the short hard segments is strengthening. The DSC analysis revealed that the glass-transition temperature of the soft segment of PUI rose in value from Ϫ42 to Ϫ3.4°C with the introduction of MH and different MH segments. The DSC results suggest that the soft segment is more compatible with the hard segment rigidity increase. The TGA results showed the hard segment structure symmetry has a more important role in the MHPUI thermal stability. Every sample containing symmetrical structure short hard groups (4,4Ј-diphenylmethane diisocyanate or 4,4Ј-diaminodiphenylmethane) is more thermally stable than that with worse symmetry structure groups (2,4-toluene diisocyanate or 3,3Ј-dichloro-4,4Ј-diaminodiphenylmethane). The three-step mechanism of PUI thermal degradation was further verified by the TGA study. The thermally unstable group was confirmed as urethane or a urea-urethane segment. The TGA results showed that MHPUI copolymers with higher separation of the soft-hard phase have higher thermal stability.

show abstract

“…The MDI polymers B2 and B0 were prepared as part of a previous multitechnique study, 9 and the original sample labels are used here. The B2 polymer is formed by the reaction of a soft-segment prepolymer (OCN-X-NCO) and a hard segment prepolymer (HO-Y-OH) (see Chart 1 for identity of X, Y units).…”

Section: Introductionmentioning

confidence: 99%

Near-Edge X-ray Absorption Fine Structure Spectroscopy of MDI and TDI Polyurethane Polymers

et al. 1999

View full text Add to dashboard Cite

The sensitivity of near-edge X-ray absorption fine structure (NEXAFS) to differences in key chemical components of polyurethane polymers is presented. Carbon 1s NEXAFS spectra of polyurethane polymers made from 4,4′-methylene di-p-phenylene isocyanate (MDI) and toluene diisocyanate (TDI) isocyanate monomers illustrate that there is an unambiguous spectroscopic fingerprint for distinguishing between MDIbased and TDI-based polyurethane polymers. NEXAFS spectra of MDI and TDI polyurea and polyurethane models show that the urea and carbamate (urethane) linkages in these polymers can be distinguished. The NEXAFS spectroscopy of the polyether component of these polymers is discussed, and the differences between the spectra of MDI and TDI polyurethanes synthesized with polyether polyols of different molecular composition and different molecular weight are presented. These polymer spectra reported herein provide appropriate model spectra to represent the pure components for quantitative microanalysis.

show abstract

Model MDI/butanediol polyurethanes: Molecular structure, morphology, physical and mechanical properties

Cited by 150 publications

References 44 publications

Synthesis and characterization of novel Schiff base polyurethanes

Synthesis and characterization of novel Schiff base polyurethanes

Study on synthesis and thermal properties of polyurethane–imide copolymers with multiple hard segments

Near-Edge X-ray Absorption Fine Structure Spectroscopy of MDI and TDI Polyurethane Polymers

Contact Info

Product

Resources

About