Abstract: A urea-modified polyurethane having excellent characteristics is prepared by the reaction between a polyisocyanate and a polyol in the presence of a diamine having the formula ##STR1## in which R.sup.1 and R.sup.2 are independently straight-chain C.sub.2 -C.sub.6 alkyl, and m and n are independently either 1 or 2. The preferred polyol is castor oil, and in preferred methods the reaction is carried out by first forming a prepolymer of the polyisocyanate with the polyol, and then curing this with a solution of the diamine in a further amount of the polyol.

Abstract: The present invention is directed to improved separatory devices employing polyurethane forming compositions, such as hollow fiber separatory devices intended to be used in biomedical applications. The separatory device employs at least one separatory membrane, suitable for the intended end use application, which is secured, potted or sealed in a housing using a cured polyurethane composition. The improvement comprises utilizing as the potting agent a polyurethane composition comprising the reaction product of an NCO-terminated prepolymer and a hydroxy terminated lactone derived polyester. The lactone polyester comprises the reaction product of a lactone such as caprolactone, and a polyol such as 1,6-hexane diol. The lactone derived polyester imparts to the polyurethane-forming composition a desirable balance of properties, including low mix viscosity, high reactivity, i.e., low gel and demold times, and acceptable hardness values, when used as a potting agent in biomedical separatory devices.

Abstract: Novel thixotropic polyurethane compositions particularly useful as sealants for the edges of folded membrane separatory devices are provided which comprise;(a) a prepolymer comprising the reaction product of a polyol having a hydroxyl functionality of at least 2 with one mole per hydroxy group of said polyol of an organic diisocyanate; and(b) a crosslinking agent comprising a polyether polyol having a hydroxyl functionality of at least 2 and a primary amine-terminated polyether having an amine functionality of at least 2.To accelerate curing of the composition, the crosslinking agent can be modified by employing primary hydroxyl-terminated polyethers and/or adding hydroxyl-containing tertiary amines.

Abstract: The present invention is directed to improvements in non-toxic polyurethane compositions and separatory devices employing the same, such as hollow fiber separatory devices intended to be used in biomedical applications. The separatory device employs at least one separatory membrane suitable for the intended end use application which is secured, potted or sealed in a housing using a cured flexible polyurethane composition. The improvement in the polyurethane composition employed in the separatory device is achieved by reacting at least one NCO-terminated prepolymer and at least one polyol in the presence of a ricinoleic acid reactive catalyst. The catalyst reduces the curing time of the polyurethane resin and because it is sufficiently reactive with the NCO-terminated prepolymer, it is incorporated into the structure of the polyurethane and cannot be released during operation of the separatory device.

Abstract: A non-wicking polyurethane casting system has been developed which comprises the reaction product obtained by admixing a polyol containing N-N-N'-N'-tetrakis (2-hydroxypropyl) ethylene diamine, (hereafter referred to as QUADROL) with an isocyanate terminated polyurethane based prepolymer. This non-wicking casting system is useful as a potting compound in biomedical applications such as dialysis and hemoultrafiltration devices and the like.

Abstract: A hollow fiber separatory device is provided wherein a polyurethane prepolymer is cross-linked or cured with an ester of a polyhydric alcohol which contains two or three hydroxyl groups, e.g., propylene glycol monoricinoleate, and an aliphatic acid of at least 12 carbon atoms and one or more epoxy and/or hydroxy groups per molecule.

Abstract: A non-wicking polyurethane casting system has been developed which comprises the reaction product obtained by admixing a polyol containing N-N-N'-N'-tetrakis (2-hydroxypropyl) ethylene diamine, (hereafter referred to as QUADROL) with an isocyanate terminated polyurethane based prepolymer. This non-wicking casting system is useful as a potting compound in biomedical applications such as dialysis and hemoultrafiltration devices and the like.