The reaction of toluene diisocyanate (TDI) with dimethylol propionic acid (DMPA) or diaminopentane sulphonic acid sodium salt and other additives to form the structure of anionic polyurethane (PU) ionomer molecule has been proven by FT-IR spectroscopy.In aqueous solution, the surface tension of anionic PU ionomer molecule is seen to slightly increase with increasing concentration of ES-200. This is because the adsorption of hydrophobic groups of ionomer molecules at the surface of aqueous solution becomes even more ordered. Under the same experimental conditions, the surface tension of anionic PU ionomer molecule appears to slightly decrease with increasing concentration of DMPA, as a result of increased hydrophobic groups of ionomer molecule adsorbed at the surface of aqueous solution. The number average particle size of anionic PU ionomer molecule in aqueous solution appears to steadily increase with an increase in the concentration of DMPA or ES-200. This is because the intermolecular interaction between ionomer±ionomer molecules themselves and between ionomer±water molecules may increase the free volume of anionic PU ionomer molecule, thus causing their number average particle size to increase.Experimental results indicate that both the tensile strength and the modulus of self-cured film of anionic PU ionomer molecule appear to decrease with increasing concentration of DMPA or ES-200, as a result of intramolecular interaction. However, the elongation of self-cured film of anionic PU ionomer molecule is seen to increase with increasing concentration of DMPA or ES-200. This may be the result of weakening crosslinking due to strong intramolecular interaction of ionomer molecule. For the peel strength of self-cured film of anionic PU ionomer coated on the fabric (30% polyester/ 70% cotton), it has been found that the peel strength increases with increasing concentration of DMPA or ES-200, as a result of increased hydrophilic interaction between ionomer molecules themselves.

An efficient synthesis of novel oxazolidinone derivatives is disclosed. Novel oxazolidinone derivatives were synthesized by a copper‐catalyzed N‐arylation reaction with control of the substituents on both the sides of the phenyl ring.

Oxygen‐permeable polyurethane ionomers with dimethyldimethoxysilane or dimethyldimethoxysilane have been successfully synthesized at our lab, and their ionomer structures have been proven by infrared spectra. In our previous paper,1 it was found that the amount of oxygen permeated through the film made by a dimethyldichlorosilane polyurethane ionomer increased with increasing the concentration of dimethyldichlorosilane. Presently, our experimental results also indicate that use of dimethyldimethoxysilane or dimethyldiethoxysilane in preparing polyurethane ionomers does substantially raise the amount of oxygen diffusing into the films made by these ionomers. These results suggest that use of dimethyldichlorosilane, dimethyldimethoxysilane, or dimethyldiethoxysilane, with strong hydrophilic property, in making polyurethane ionomer will give better oxygen permeability of siloxane‐based polyurethane ionomers. It is interesting to point out that both tensile strength and the elongation of a siloxane‐based polyurethane ionomer film become weaker as the concentration of dimethyldimethoxysilane or dimethyldiethoxysilane increases. This may be the result of intramolecular interaction of ionomer molecules, coupled with the reduction of the formation of hydrogen bonding between ionomer‐ionomer molecules and between ionomer‐water molecules. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1932–1938, 2000

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