Phase studies of a urethane model compound and polyether macroglycols by infrared spectroscopy and the relationship between eutectic composition of soft segment and blood compatibility
✍ Scribed by Isama, Kazuo ;Kojima, Shigeo ;Nakamura, Akitada
- Book ID
- 102873215
- Publisher
- John Wiley and Sons
- Year
- 1993
- Tongue
- English
- Weight
- 607 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0021-9304
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✦ Synopsis
The binary mixtures of a urethane model compound, diethyl 4,4'-methylenebis(N-phenylcarbamate) (MDU), and various polyether macroglycols have been investigated mainly by infrared (IR) spectroscopy. The mixtures of macroglycol and MDU showed two C=O bands (free C=O at higher wave number, hydrogen bonded C=O at lower wave number), and the intensity of free C=O increased while that of hydrogen bonded C=O decreased linearly with increasing molar ratio of macroglycol/MDU. The slope of the increase or decrease suddenly changed at the specific molar ratio around the eutectic composition. The eutectic molar composition for PTM01000/MDU was determined as 1.15 or 1.1 by differential scanning calorimetry (DSC) or infrared (IR) studies while that for PTM03000 / MDU as 0.345 or 0.55 by DSC or IR, respectively. The eutectic compositions for other sets were determined by IR studies as follows: PE01000/MDU, 0.4; PE03000/MDU, 0.16; PPO1000/MDU, 1.4; PP03000/MDU, 0.45. The number of ethylene oxide, tetramethylene oxide, and propylene oxide units to form a eutectic with MDU calculated from these values were 15-20, 10-11, and 23-24, respectively. The similar DSC or IR changes were observed in the various kinds of polyurethanes such as MDI / BD, MDI / PTMO / BD, and MDI / PTMO polymers. The relationship between the eutectic compositions of soft segments (MDI/macroglycol) and the ideal M, of the macroglycols in blood compatibility of segmented polyurethanes are discussed.