According to one embodiment, a system for manufacturing a fully impregnated thermoplastic prepreg includes a mechanism for moving a fabric or mat and a drying mechanism that removes residual moisture from at least one surface of the fabric or mat. The system also includes a resin application mechanism that applies a reactive resin to the fabric or mat and a press mechanism that presses the coated fabric or mat to ensure that the resin fully saturates the fabric or mat. The system further includes a curing oven through which the coated fabric or mat is moved to polymerize the resin and thereby form a thermoplastic polymer so that upon exiting the oven, the fabric or mat is fully impregnated with the thermoplastic polymer. During at least a portion of the process, humidity in the vicinity of the coated fabric or mat is maintained at substantially zero.

The present invention relates to a process for producing a polyamide powder (PP) comprising at least one semicrystalline polyamide (P) and at least one additive (A). The semicrystalline polyamide (P) and the at least one additive (A) are initially compounded with one another in an extruder and subsequently introduced into a solvent (SV) in which the at least one semicrystalline polyamide (P) then crystallizes to obtain the polyamide powder (PP). The present invention further relates to the thus obtainable polyamide powder (PP) and to the use of the polyamide powder (PP) as sintering powder (SP) and also to a process for producing a shaped body by selective laser sintering of a polyamide powder (PP).

A process tear production of high molecular weight polyamide polymers, such as 6/66 copolymers, using a reactant stream that includes at least one lactam and cyclic oligomers. The stream is reacted with at least one diamine at an elevated temperature ring-open the cyclic oligomers to produce amide pre-polymers that are end-capped with amine groups. The pre-polymers are then reacted with at least one diacid at an elevated temperature to form polyamide 6/66 copolymers. The cyclic oligomers may be formed as by-products during standard polymerization of polyamide polymers from monomers such as caprolactam, hexamethylene diamine and adipic acid.

A process tear production of high molecular weight polyamide polymers, such as 6/66 copolymers, using a reactant stream that includes at least one lactam and cyclic oligomers. The stream is reacted with at least one diamine at an elevated temperature ring-open the cyclic oligomers to produce amide pre-polymers that are end-capped with amine groups. The pre-polymers are then reacted with at least one diacid at an elevated temperature to form polyamide 6/66 copolymers. The cyclic oligomers may be formed as by-products during standard polymerization of polyamide polymers from monomers such as caprolactam, hexamethylene diamine and adipic acid.

A three-dimensional star-shaped α-helix polypeptide having a high-efficiency gene delivery capability, and a preparation method and an application thereof. A dendrimer is used as an initiator and dichloromethane is used as a reaction solvent to initiate high-speed ring-opening polymerization of different types of N-carboxylic anhydride monomers, and groups having different electrical properties are introduced at the ends via click chemistry reactions. The abundant amino groups on the surface of the dendrimer provide enough polymerization sites to enable the polypeptide to form a three-dimensional spherical topological structure, and the topological structure provides an opportunity for initial acceleration of the ring-opening polymerization reaction. The higher positive charge density caused by polypeptide side chain modified guanidine/amino groups etc. achieves a high-efficiency gene loading capability by the electrostatic effect between positive and negative charges, and the α-helix rigid structure on the secondary structure thus enables the polypeptide to have stronger membrane penetration capability.

A three-dimensional star-shaped α-helix polypeptide having a high-efficiency gene delivery capability, and a preparation method and an application thereof. A dendrimer is used as an initiator and dichloromethane is used as a reaction solvent to initiate high-speed ring-opening polymerization of different types of N-carboxylic anhydride monomers, and groups having different electrical properties are introduced at the ends via click chemistry reactions. The abundant amino groups on the surface of the dendrimer provide enough polymerization sites to enable the polypeptide to form a three-dimensional spherical topological structure, and the topological structure provides an opportunity for initial acceleration of the ring-opening polymerization reaction. The higher positive charge density caused by polypeptide side chain modified guanidine/amino groups etc. achieves a high-efficiency gene loading capability by the electrostatic effect between positive and negative charges, and the α-helix rigid structure on the secondary structure thus enables the polypeptide to have stronger membrane penetration capability.

A method produces polyamide fine particles by polymerizing a polyamide monomer (A) in the presence of a polymer (B) at a temperature equal to or higher than the crystallization temperature of a polyamide to be obtained, wherein the polyamide monomer (A) and the polymer (B) are homogeneously dissolved at the start of polymerization, and polyamide fine particles are precipitated after the polymerization. Polyamide fine particles have a number average particle size of 0.1 to 100 μm, a sphericity of 90 or more, a particle size distribution index of 3.0 or less, a linseed oil absorption of 100 mL/100 g or less, and a crystallization temperature of 150° C. or more. In particular, a polyamide having a high crystallization temperature includes fine particles having a smooth surface, a narrow particle size distribution, and high sphericity.

A method produces polyamide fine particles by polymerizing a polyamide monomer (A) in the presence of a polymer (B) at a temperature equal to or higher than the crystallization temperature of a polyamide to be obtained, wherein the polyamide monomer (A) and the polymer (B) are homogeneously dissolved at the start of polymerization, and polyamide fine particles are precipitated after the polymerization. Polyamide fine particles have a number average particle size of 0.1 to 100 μm, a sphericity of 90 or more, a particle size distribution index of 3.0 or less, a linseed oil absorption of 100 mL/100 g or less, and a crystallization temperature of 150° C. or more. In particular, a polyamide having a high crystallization temperature includes fine particles having a smooth surface, a narrow particle size distribution, and high sphericity.

A method produces polyamide fine particles by polymerizing a polyamide monomer (A) in the presence of a polymer (B) at a temperature equal to or higher than the crystallization temperature of a polyamide to be obtained, wherein the polyamide monomer (A) and the polymer (B) are homogeneously dissolved at the start of polymerization, and polyamide fine particles are precipitated after the polymerization. Polyamide fine particles have a number average particle size of 0.1 to 100 μm, a sphericity of 90 or more, a particle size distribution index of 3.0 or less, a linseed oil absorption of 100 mL/100 g or less, and a crystallization temperature of 150° C. or more. In particular, a polyamide having a high crystallization temperature includes fine particles having a smooth surface, a narrow particle size distribution, and high sphericity.

A method produces polyamide fine particles by polymerizing a polyamide monomer (A) in the presence of a polymer (B) at a temperature equal to or higher than the crystallization temperature of a polyamide to be obtained, wherein the polyamide monomer (A) and the polymer (B) are homogeneously dissolved at the start of polymerization, and polyamide fine particles are precipitated after the polymerization. Polyamide fine particles have a number average particle size of 0.1 to 100 μm, a sphericity of 90 or more, a particle size distribution index of 3.0 or less, a linseed oil absorption of 100 mL/100 g or less, and a crystallization temperature of 150° C. or more. In particular, a polyamide having a high crystallization temperature includes fine particles having a smooth surface, a narrow particle size distribution, and high sphericity.