A subject-matter of the present invention are new complexes comprising cyclic alkylene carbonates and polyamides, processes for their preparation and uses. Additionally, a subject-matter of the invention is the use of alkylene carbonates for recycling, solubilization, purification, and/or powdering of polyamide-based materials.

This invention relates to polyamide-10 and a method for preparing the same, and according to this invention, polyamide-10 having superior mechanical and thermal properties can be prepared by preparing polyamide-10 while controlling the condensation polymerization conditions of 10-aminodecanoic acid.

A method of synthesizing polyamide microparticles may comprise: dehydrating and shearing a mixture comprising a matrix fluid, an emulsion stabilizer at about 0.01 wt % to about 50 wt % based on the weight of the matrix fluid, a solvent at about 13 wt % to about 75 wt % based on the weight of the matrix fluid, and a cyclic amide monomer at about 20 wt % to about 90 wt % based on the weight of the matrix fluid to yield an emulsion having a water content of about 1 wt % or less based on the total weight of the emulsion; adding a deprotonating agent to the emulsion at a concentration of about 0.01 wt % to about 1 wt % based on the weight of the matrix fluid; and contacting the emulsion with a polymerization initiator under conditions effective to polymerize the cyclic amide monomer into a plurality of polyamide microparticles.

A method of synthesizing polyamide microparticles may comprise: dehydrating and shearing a mixture comprising a matrix fluid, an emulsion stabilizer at about 0.01 wt % to about 50 wt % based on the weight of the matrix fluid, a solvent at about 13 wt % to about 75 wt % based on the weight of the matrix fluid, and a cyclic amide monomer at about 20 wt % to about 90 wt % based on the weight of the matrix fluid to yield an emulsion having a water content of about 1 wt % or less based on the total weight of the emulsion; adding a deprotonating agent to the emulsion at a concentration of about 0.01 wt % to about 1 wt % based on the weight of the matrix fluid; and contacting the emulsion with a polymerization initiator under conditions effective to polymerize the cyclic amide monomer into a plurality of polyamide microparticles.

A method of synthesizing polyamide microparticles may comprise: dehydrating and shearing a mixture comprising a matrix fluid, an emulsion stabilizer at about 0.01 wt % to about 50 wt % based on the weight of the matrix fluid, a solvent at about 13 wt % to about 75 wt % based on the weight of the matrix fluid, and a cyclic amide monomer at about 20 wt % to about 90 wt % based on the weight of the matrix fluid to yield an emulsion having a water content of about 1 wt % or less based on the total weight of the emulsion; adding a deprotonating agent to the emulsion at a concentration of about 0.01 wt % to about 1 wt % based on the weight of the matrix fluid; and contacting the emulsion with a polymerization initiator under conditions effective to polymerize the cyclic amide monomer into a plurality of polyamide microparticles.

A method of synthesizing polyamide microparticles may comprise: dehydrating and shearing a mixture comprising a matrix fluid, an emulsion stabilizer at about 0.01 wt % to about 50 wt % based on the weight of the matrix fluid, a solvent at about 13 wt % to about 75 wt % based on the weight of the matrix fluid, and a cyclic amide monomer at about 20 wt % to about 90 wt % based on the weight of the matrix fluid to yield an emulsion having a water content of about 1 wt % or less based on the total weight of the emulsion; adding a deprotonating agent to the emulsion at a concentration of about 0.01 wt % to about 1 wt % based on the weight of the matrix fluid; and contacting the emulsion with a polymerization initiator under conditions effective to polymerize the cyclic amide monomer into a plurality of polyamide microparticles.

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.

Embodiments relate to a polymer film that is excellent in folding characteristics and transparency and maintains excellent mechanical properties even after repeated elongation and shrinkage in the elastic region, a process for preparing the same, and a front panel and a display device comprising the same. The polymer film comprises a polymer resin selected from the group consisting of a polyamide-based resin and a polyimide-based resin and has an MOR.sub.0/9 of Equation A of 2% or less.

Embodiments relate to a polymer film that is excellent in folding characteristics and transparency and maintains excellent mechanical properties even after repeated elongation and shrinkage in the elastic region, a process for preparing the same, and a front panel and a display device comprising the same. The polymer film comprises a polymer resin selected from the group consisting of a polyamide-based resin and a polyimide-based resin and has an MOR.sub.0/9 of Equation A of 2% or less.