Abstract: The present invention relates to a polyurethane polymer composition prepared by reacting a mixture comprising: a} at least one polyethylene glycol, and either b) at least one poly-isocyanate, having a functionality greater than 2 or c) at least one di-isocyanate and at least one polyol or at least one macropolyol having a functionality greater than 2, wherein the polyol or macropolyol is present at an amount of 0.1 to 9 wt % of the mixture. The invention also relates to a process for preparing a polyurethane xerogel in the form of a molded article, said process comprising the steps of: i.) preparing said mixture; ii.) dispensing the reaction mixture formed in step i) into a mold; iii.) allowing the reaction mixture to react and cure; iv.) removing the molded article from the mold; and v.) hydrating the molded article.

Abstract: The present invention relates to a polyurethane polymer prepared from a mixture comprising: (a) at least one polyol of formula (I), wherein at least three of X1, X2, X3, X4 and X5 are each independently an OH-terminated polyoxyalkylene group, and the remainder of X1, X2, X3. X4 and X5 are each independently H or absent, and Z is a central linking unit; (b) at least one di- or poly-isocyanate; and (c) optionally at least one OH-terminated chain extender. Further aspects of the invention relate to a process for preparing a polyurethane, and to a process for preparing a contact lens.

Abstract: The present invention relates to a thermoplastic polyurethane contact lens prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; and (c) at least one diol of formula (I): wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a contact lens.

Abstract: The present invention relates to a polyurethane polymer composition comprising polyethyleneglycol dialkyl ether. There is also provided a process for preparing a polyurethane. The invention also relates to a process for preparing a polyurethane xerogel in the form of a molded article, said process comprising the steps of: i. preparing a mixture of a. at least one polyethylene glycol or at least one polyol of formula I, wherein at least three of X1, X2, X3, X4 and X5 are each independently an OH-terminated group, and the remainder of X1, X2, X3, X4 and X5 are each independently H or absent, and Z is a central linking unit, a. at least one di- or poly-isocyanate, b. optionally at least one OH-terminated chain extender, and c. at least one polyethyleneglycol dialkyl ether; ii. dispensing the reaction mixture formed in step i) into a mold; iii. allowing the reaction mixture to react and cure; iv. removing the molded article from the mold; and v. hydrating the molded article.

Abstract: The present invention relates to a polyurethane prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; (c) at least one polydialkyl siloxane diol; and (d) at least one diol of formula (I) wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate, polydialkyl siloxane diol and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a polyurethane.

Abstract: The present invention relates to polyurethane polymer compositions prepared by reacting a mixture comprising: a) at least one poly(ethylene glycol), b) at least one polyoxyalkylene diol (typically PPG or a copolymer of ethylene oxide and propylene oxide), c) at least one di- or poly-isocyanate, d) at least one polyol or macropolyol having a functionality greater than 2, or a mixture of such polyols or macropolyols having a functionality greater than 2, e) optionally an additional compound comprising at least one hydroxyl group and at least one primary or secondary amine group. The present invention also relates to an article comprising such a polymer, in particular a medical device such as a contact lens. A process for preparing a polyurethane hydrogel is also provided.

Abstract: The present invention relates to a polyurethane polymer composition prepared by reacting a mixture comprising: a} at least one polyethylene glycol, and either b) at least one poly-isocyanate, having a functionality greater than 2 or c) at least one di-isocyanate and at least one polyol or at least one macropolyol having a functionality greater than 2, wherein the polyol or macropolyol is present at an amount of 0.1 to 9 wt % of the mixture. The invention also relates to a process for preparing a polyurethane xero-gel in the form of a moulded article, said process comprising the steps of: i.) preparing said mixture; ii. ) dispensing the reaction mixture formed in step i) into a mould; iii. ) allowing the reaction mixture to react and cure; iv. ) removing the moulded article from the mould; and v. ) hydrating the moulded article.

Abstract: The present invention relates to a polyurethane polymer prepared from a mixture comprising: (a) at least one polyol of formula (I), wherein at least three of X1, X2, X3, X4 and X5 are each independently an OH-terminated polyoxyalkylene group, and the remainder of X1, X2, X3. X4 and X5 are each independently H or absent, and Z is a central linking unit; (b) at least one di- or poly-isocyanate; and (c) optionally at least one OH-terminated chain extender. Further aspects of the invention relate to a process for preparing a polyurethane, and to a process for preparing a contact lens.

Abstract: The present invention relates to a polyurethane polymer composition comprising polyethyleneglycol dialkyl ether. There is also provided a process for preparing a polyurethane. The invention also relates to a process for preparing a polyurethane xerogel in the form of a molded article, said process comprising the steps of: i. preparing a mixture of a. at least one polyethylene glycol or at least one polyol of formula (I), wherein at least three Of X1, X2, X3, X4 and X5 are each independently an OH-terminated group, and the remainder of X1, X2, X3, X4 and X5 are each independently H or absent, and Z is a central linking unit, a. at least one di- or poly-isocyanate, b. optionally at least one OH-terminated chain extender, and c. at least one polyethyleneglycol dialkyl ether; ii. dispensing the reaction mixture formed in step i) into a mold; iii. allowing the reaction mixture to react and cure; iv. removing the molded article from the mold; and v. hydrating the molded article.

Abstract: The present invention relates to a polyurethane prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; (c) at least one polydialkyl siloxane diol; and (d) at least one diol of formula (I) wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate, polydialkyl siloxane diol and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a polyurethane.

Abstract: The present invention relates to a thermoplastic polyurethane contact lens prepared from a mixture comprising: (a) at least one polyethylene glycol; (b) at least one di-isocyanate; and (c) at least one diol of formula (I): wherein n is an integer from 1 to 25; wherein the polyethylene glycol, di-isocyanate and diol are reacted under substantially anhydrous conditions. Further aspects of the invention relate to a process for preparing a contact lens.

Abstract: The present invention relates to a method of using non-macrogelled polymer-solvent combinations to form devices, in particular medical devices and/or cosmetic devices, more specifically contact lenses. The method of using polymer solvent combinations is suitable for forming useful 3D dimensionally stable structures which may include curved surfaces, which may be significantly different to those curved surfaces achieved by using simple meniscus effects.

Abstract: A linear random block copolymer comprising segments of polyethylene oxide and a relatively more hydrophobic polymer, e.g. polypropylene oxide connected by hydrophobic segments containing urethane and urea groups formed from the reaction of a di-isocyanate and a diamine, wherein the diamine comprises less than 2% by weight of the total weight of the reactants used in the preparation of the copolymer.

Abstract: A linear random block copolymer comprising segments of polyethylene oxide and a relatively more hydrophobic polymer, e.g. polypropylene oxide connected by hydrophobic segments containing urethane and urea groups formed from the reaction of a di-isocyanate and a diamine, wherein the diamine comprises less than 2% by weight of the total weight of the reactants used in the preparation of the copolymer.

Abstract: A microgel is produced by a two-stage process wherein the monomers are first polymerized in the absence of solvent for a controlled period, and in a second stage solvent is added and polymerization is completed. The polymer is preferably a polyurethane formed from a polyalkylene glycol, a triol and a diisocyanate. The molecular weight is typically 100,000 to 200,000. The microgels form granules which may be compressed into solid form. Such solid forms containing an active agent, such as a protein, are useful as sustained delivery devices.

Abstract: A solution polymerization process for the preparation of a polymeric material having a weight average molecular weight from 5,000 to 20,000,000 and comprising cross-linked particles which are capable of forming a sol in the reaction solvent, which process comprises:(i) polymerizing one or more monomers, the or at least one of which is a cross-linking agent, in a solvent which (a) has a solubility parameter from 2.5 cal.sup.1/2 ml.sup.-3/2 below to 1.0 cal.sup.1/2 ml.sup.-3/2 above the solubility parameter of the bulk polymeric material and (b) is of the same or adjacent hydrogen bonding group as the bulk polymeric material;(ii) monitoring the polymerization until polymeric material as herein defined is obtained; and(iii) terminating the polymerization before gelation is observed.

Abstract: a porous solid material for plant propagation which includes granules of a porous expanded mineral, such as perlite or vermiculite, distributed within a porous, open-cell foamed hydrophilic water-retentive polyurethane matrix. The material may be molded into sheets of break-off units for seed germination and propagation.