A polyimide-forming composition includes a particulate polyimide precursor composition having an average particle size of 0.1 to 100 micrometers wherein the polyimide precursor composition comprises a substituted or unsubstituted C.sub.4-40 bisanhydride, and a substituted or unsubstituted divalent C.sub.1-20 diamine; an aqueous carrier; and a surfactant. A method of manufacturing an article including a polyimide includes the steps of forming a preform comprising the polyimide-forming composition; and heating the preform at a temperature and for a period of time effective to imidize the polyimide precursor composition and form the polyimide. An article prepared by the method, and a layer or coating including a polyimide and a surfactant are also described.

The invention relates to a method of manufacturing a heart valve, comprising: a step of injection moulding a first part (110) of the heart valve from a first block-copolymer, wherein the injection moulding is performed at a temperature below an order-disorder transition temperature of the block copolymer, such that a phase structure is present in the molten block-copolymer; a step of injection moulding a second part (114) of the heart valve from a second block-copolymer that is different to the first block-copolymer, by over-moulding over the first part (110) to form an over-moulded structure, wherein the injection moulding is performed at a temperature below order-disorder transition temperatures for the first and second block copolymers, such that a phase structure is present in the molten second block-copolymer and remains present in the first block-copolymer; and a step of cooling the over-moulded structure, without heating it above the order-disorder transition temperatures between the step of injection moulding the second part (114) and the step of cooling, so as to preserve an arrangement of the phase structures created during the steps of injection moulding and produce anisotropic physical properties in the second part (114). The invention also relates to the thus manufactured heart valve.

A method includes subjecting an ophthalmic device mold-forming material to drying conditions in a first inert gas environment for a time period sufficient to substantially dry the ophthalmic device mold-forming material; molding a first ophthalmic device mold part and a second ophthalmic device mold part from the dried ophthalmic device mold-forming material; and subjecting the first ophthalmic device mold part and the second ophthalmic device mold part to a second inert gas environment for a time period sufficient to substantially remove all oxygen in the first ophthalmic device mold part and the second ophthalmic device mold part.

A polyimide-forming composition includes a particulate polyimide precursor composition having an average particle size of 0.1 to 100 micrometers wherein the polyimide precursor composition comprises a substituted or unsubstituted C.sub.4-40 bisanhydride, and a substituted or unsubstituted divalent C.sub.1-20 diamine; an aqueous carrier; and a surfactant. A method of manufacturing an article including a polyimide includes the steps of forming a preform comprising the polyimide-forming composition; and heating the preform at a temperature and for a period of time effective to imidize the polyimide precursor composition and form the polyimide. An article prepared by the method, and a layer or coating including a polyimide and a surfactant are also described.

A polyimide-forming composition includes a particulate polyimide precursor composition having an average particle size of 0.1 to 100 micrometers wherein the polyimide precursor composition comprises a substituted or unsubstituted C.sub.4-40 bisanhydride, and a substituted or unsubstituted divalent C.sub.1-20 diamine; an aqueous carrier; and a surfactant. A method of manufacturing an article including a polyimide includes the steps of forming a preform comprising the polyimide-forming composition; and heating the preform at a temperature and for a period of time effective to imidize the polyimide precursor composition and form the polyimide. An article prepared by the method, and a layer or coating including a polyimide and a surfactant are also described.

A polyimide-forming composition includes a particulate polyimide precursor composition having an average particle size of 0.1 to 100 micrometers wherein the polyimide precursor composition comprises a substituted or unsubstituted C.sub.4-40 bisanhydride, and a substituted or unsubstituted divalent C.sub.1-20 diamine; an aqueous carrier; and a surfactant. A method of manufacturing an article including a polyimide includes the steps of forming a preform comprising the polyimide-forming composition; and heating the preform at a temperature and for a period of time effective to imidize the polyimide precursor composition and form the polyimide. An article prepared by the method, and a layer or coating including a polyimide and a surfactant are also described.