Polyurethane (PU) anionomers were prepared as aqueous dispersions using dimethylol propionic acid (DMPA) as the stabilizing moiety. The principal diols used were polytetrahydrofuran of molecular weight 1000 (PTHF1000) and cyclohexane dimethanol (CHDM). The diisocyanates used in this study were isoph
Synthesis and properties of highly hydrophilic polyurethane based on diisocyanate with ether group
โ Scribed by Ken Kojio; Yoshitaka Mitsui; Mutsuhisa Furukawa
- Publisher
- Elsevier Science
- Year
- 2009
- Tongue
- English
- Weight
- 553 KB
- Volume
- 50
- Category
- Article
- ISSN
- 0032-3861
No coin nor oath required. For personal study only.
โฆ Synopsis
Highly hydrophilic polyurethane elastomers (PUEs) were synthesized from 1,2-bis(isocyanate) ethoxyethane (TEGDI), poly(ethylene oxide-co-propylene oxide) copolyol (EOPO) and 1,4-butane diol/1,1,1-trimethylol propane (75/25) (wt/wt) by a prepolymer method. 4,4 0 -Diphenylmethane diisocyanate (MDI)-based PUEs were synthesized as a control as well. Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC) measurements revealed that the degree of microphase separation of the TEGDI-based PUEs was much weaker than for the MDI-based PUEs. Young's modulus and elongation at break of the TEGDI-based PUEs were quite lower and larger than for the MDI-based PUEs, respectively. This is due to quite weak cohesion force of the hard segment chains in the TEGDIbased PUEs. The degree of swelling of the TEGDI-based PUEs was five times larger than for the MDI-based one. This is associated with the hydrophilic nature of TEGDI and weak cohesion force in the TEGDI-based PUEs.
๐ SIMILAR VOLUMES
The curing behaviour of a series of polyurethanes based on modiยฎed methyleneยฑdiphenyl diisocyanate (MDI) and poly(propylene oxide) polyols was studied using isothermal Fourier-transform infrared spectroscopy (FTIR), temperature-ramped differential scanning calorimetry (DSC) and adiabatic exotherm ex
## Abstract A polyurethane (PU)/clay nanocomposite was synthesized from polyol, polymeric 4,4โฒโdiphenyl methane diisocyanate (PMDI), and modified clay with PMDI. To achieve the modified clay with PMDI, the silanol group of the clay and the NCO group of the PMDI were reacted for 24 h at 50ยฐC to form
Three series of polyurethanes were prepared having 42 wt % hard segments based on 4,4ะ-dicyclohexyl methane diisocyanate (H 12 MDI) with trans,trans isomer contents in the 13 to 95 mol % range and 1,4-butanediol chain extender. The soft segments were based on macrodiols poly(hexamethylene oxide) (PH