Formulation systems usable for fabricating a three-dimensional object made of a polyamide-containing material, by three-dimensional 3D inkjet printing, and methods and systems utilizing same, are provided. The formulation systems are formed of at least a first and second model formulations containing a lactam and a catalyst for inducing anionic ring opening polymerization of the lactam in the first formulation, and an activator for promoting anionic ring opening polymerization of the lactam in the second formulation, and are further characterized as: including in the first and/or second formulation a compound capable of increasing a rate of said polymerization upon exposure to said curing energy; including as an activator a lactam-blocked polyisocyanate; and/or as including in the first model formulation at least one material capable of reducing a melting point of said first model formulation. Formulation systems usable at a selected ratio are also provided.

The present invention relates to a method for preparing a polyamide by anionic ring-opening copolymerization in consideration of the reactivity between a monomer and an alkali metal-based initiator. The present invention relates to a method for preparing a polyamide by anionic ring-opening copolymerization and a polyamide prepared thereby, in which, by adding a metal hydride, which is an alkali metal-based initiator, to a lactam having higher reactivity therewith, a production rate of an anion-initiated monomer is increased, thus enabling polymerization with a high conversion rate within a short polymerization reaction time to obtain a polymer having a uniform molecular weight. In the method for preparing the polyamide by anionic ring-opening copolymerization (AROP), a metal hydride is added as an alkali metal-based initiator in an amount of 0.01-20 parts by weight based on 100 parts by weight of two or more lactams, and the alkali metal-based initiator is mixed with a lactam having higher reactivity among two lactams. Therefore, the metal hydride, which is the alkali metal-based initiator, is added to the monomer having high reactivity therewith to increase a production rate of an anion-initiated monomer and improve a conversion rate into a random copolymer.

The present invention relates to a method for preparing a polyamide by anionic ring-opening copolymerization in consideration of the reactivity between a monomer and an alkali metal-based initiator. The present invention relates to a method for preparing a polyamide by anionic ring-opening copolymerization and a polyamide prepared thereby, in which, by adding a metal hydride, which is an alkali metal-based initiator, to a lactam having higher reactivity therewith, a production rate of an anion-initiated monomer is increased, thus enabling polymerization with a high conversion rate within a short polymerization reaction time to obtain a polymer having a uniform molecular weight. In the method for preparing the polyamide by anionic ring-opening copolymerization (AROP), a metal hydride is added as an alkali metal-based initiator in an amount of 0.01-20 parts by weight based on 100 parts by weight of two or more lactams, and the alkali metal-based initiator is mixed with a lactam having higher reactivity among two lactams. Therefore, the metal hydride, which is the alkali metal-based initiator, is added to the monomer having high reactivity therewith to increase a production rate of an anion-initiated monomer and improve a conversion rate into a random copolymer.

Formulation systems usable for fabricating a three-dimensional object made of a polyamide-containing material, by three-dimensional 3D inkjet printing, and methods and systems utilizing same, are provided. The formulation systems are formed of at least a first and second model formulations containing a lactam and a catalyst for inducing anionic ring opening polymerization of the lactam in the first formulation, and an activator for promoting anionic ring opening polymerization of the lactam in the second formulation, and are further characterized as: including in the first and/or second formulation a compound capable of increasing a rate of said polymerization upon exposure to said curing energy; including as an activator a lactam-blocked polyisocyanate; and/or as including in the first model formulation at least one material capable of reducing a melting point of said first model formulation. Formulation systems usable at a selected ratio are also provided.

Formulation systems usable for fabricating a three-dimensional object made of a polyamide-containing material, by three-dimensional 3D inkjet printing, and methods and systems utilizing same, are provided. The formulation systems are formed of at least a first and second model formulations containing a lactam and a catalyst for inducing anionic ring opening polymerization of the lactam in the first formulation, and an activator for promoting anionic ring opening polymerization of the lactam in the second formulation, and are further characterized as: including in the first and/or second formulation a compound capable of increasing a rate of said polymerization upon exposure to said curing energy; including as an activator a lactam-blocked polyisocyanate; and/or as including in the first model formulation at least one material capable of reducing a melting point of said first model formulation. Formulation systems usable at a selected ratio are also provided.

The present invention relates to a method for producing a polyamide by coordinated anionic ring-opening polymerization and a polyamide produced thereby, wherein metal alkoxide as an initiator and metal hydride as a catalyst are added to enable polymerization having a narrow molecular weight distribution and uniform molecular weight within a short polymerization reaction time at a low temperature, without a separate vacuum process, as compared with an existing polymerization method.

The present invention relates to a method for producing a polyamide by coordinated anionic ring-opening polymerization and a polyamide produced thereby, wherein metal alkoxide as an initiator and metal hydride as a catalyst are added to enable polymerization having a narrow molecular weight distribution and uniform molecular weight within a short polymerization reaction time at a low temperature, without a separate vacuum process, as compared with an existing polymerization method.

Provided are a method for preparing a polyamide by using a molecular weight controller having a double active group in anionic ring-opening copolymerization of a polyamide, thereby enabling molecular weight to be controlled through the addition reaction of the molecular weight controller, and a polyamide prepared thereby.

Provided are a method for preparing a polyamide by using a molecular weight controller having a double active group in anionic ring-opening copolymerization of a polyamide, thereby enabling molecular weight to be controlled through the addition reaction of the molecular weight controller, and a polyamide prepared thereby.

Provided are a method for producing a polyamide including an amide-based molecular weight controller and a polyamide produced thereby, wherein the amide-based molecular weight controller may easily control the molecular weight of the polyamide to have a narrow molecular weight distribution so as to prevent an increase in the molecular weight due to a basic intermediate produced in anionic polymerization and a side reaction generated under a high-temperature polymerization condition.