The present invention discloses a method for preparing glatiramer acetate, comprising: (1) dissolving L-alanine NCA, L-tyrosine NCA, L-glutamic acid-γ-benzyl ester NCA, and L-ε-trifluoroacetyl-lysine NCA in 1,4-dioxane as solvent, stirring until a clarified solution is formed; (2) adding diethylamine for catalysis, stirring at 20-25° C., then slowly pouring the reaction solution into water, collecting the produced white product; (3) adding the obtained product to a solution of hydrobromic acid in acetic acid, stirring at 23.0-25.0° C., pouring the reaction solution into purified water for quenching and stirring, subjecting the mixture to suction filtration to obtain a yellow solid, after repeating 3-5 times, subjecting the solid to blast drying to remove the moisture therein; and (4) dissolving the solid obtained in step (3) in a 1M piperidine aqueous solution at room temperature and stirring, subjecting the obtained solution to dialysis, adding glacial acetic acid to adjust the pH to 5.5-7.0, and lyophilizing.

The present invention discloses a method for preparing glatiramer acetate, comprising: (1) dissolving L-alanine NCA, L-tyrosine NCA, L-glutamic acid-γ-benzyl ester NCA, and L-ε-trifluoroacetyl-lysine NCA in 1,4-dioxane as solvent, stirring until a clarified solution is formed; (2) adding diethylamine for catalysis, stirring at 20-25° C., then slowly pouring the reaction solution into water, collecting the produced white product; (3) adding the obtained product to a solution of hydrobromic acid in acetic acid, stirring at 23.0-25.0° C., pouring the reaction solution into purified water for quenching and stirring, subjecting the mixture to suction filtration to obtain a yellow solid, after repeating 3-5 times, subjecting the solid to blast drying to remove the moisture therein; and (4) dissolving the solid obtained in step (3) in a 1M piperidine aqueous solution at room temperature and stirring, subjecting the obtained solution to dialysis, adding glacial acetic acid to adjust the pH to 5.5-7.0, and lyophilizing.

Provided herein are (phenylene)dialkanamines, and methods of producing such (phenylene)dialkanamines from various furanyl and benzyl compounds. Such furanyl compounds may include, for example, bis(nitroalkyl)furans, bis(aminoalkyl)furans, and nitroalkyl(furan)acetonitriles. Such compounds may include, for example, bis(nitroalkyl)benzenes. Provided herein are also alkyldiamines, and methods for producing such alkyldiamines from furanyl compounds.

A regulation method for preparing γ-polyglutamic acid by sludge substrate fermentation includes: 1) extraction of glutamic acid from sludge protein (high pressure hydrothermal treatment, gravity pressure filtration treatment), 2) secondary metabolic synthesis of γ-polyglutamic acid (activation of domesticated strains and secondary metabolic fermentation strains); and 3) preparation of pure γ-polyglutamic acid (acidification, centrifugation, filtration, precipitation based on polar repulsion, purification, impurity removal and drying). The present invention realizes a recycling of high-value carbon and nitrogen sources of sludge without secondary pollution, and has advantages of simplified operation, good feasibility, and low preparation cost. The synthesized γ-polyglutamic acid has high economic value and broad application prospect.

Compositions including polyaspartic acid and methods for preparing polyaspartic acid using a precondensate of aspartic acid and polyaspartimide are provided herein. Uses for such compositions are also described.

Compositions including polyaspartic acid and methods for preparing polyaspartic acid using a precondensate of aspartic acid and polyaspartimide are provided herein. Uses for such compositions are also described.

An industrial method for preparing a semi-aromatic copolyamide having a general formula A/10.T, wherein: A denotes a unit obtained by polycondensing a lactam or a C.sub.9-C.sub.12 amino acid; and 10.T denotes a unit obtained by polycondensing 1.10-decanediamine and terephtalic acid. The method includes a step for polycondensing the comonomers, the amino acid or the lactam, 1.10-decanediamine and terephtalic acid in the presence of at least one C.sub.1-C.sub.7 linear aliphatic acid. The level of foaming in a reactor is substantially reduced, during the polycondensation step, in relation to the level observed without C.sub.1-C.sub.7 linear aliphatic acid.

An industrial method for preparing a semi-aromatic copolyamide having a general formula A/10.T, wherein: A denotes a unit obtained by polycondensing a lactam or a C.sub.9-C.sub.12 amino acid; and 10.T denotes a unit obtained by polycondensing 1.10-decanediamine and terephtalic acid. The method includes a step for polycondensing the comonomers, the amino acid or the lactam, 1.10-decanediamine and terephtalic acid in the presence of at least one C.sub.1-C.sub.7 linear aliphatic acid. The level of foaming in a reactor is substantially reduced, during the polycondensation step, in relation to the level observed without C.sub.1-C.sub.7 linear aliphatic acid.

A process for the enzyme-catalyzed preparation of prepolymers for the production of plastics, based on an enzyme-catalyzed polymerization of monomer or oligomer compounds in a single phase aqueous solution, as well as the separation of the prepolymers precipitated therefrom and their subsequent use for the production of plastics and plastic articles obtainable therefrom. In particular, the invention relates to respective methods for enzyme-catalyzed preparation of prepolymers with polyamide-type bonding structure for the production of polyamide-based plastics.

A process for the enzyme-catalyzed preparation of prepolymers for the production of plastics, based on an enzyme-catalyzed polymerization of monomer or oligomer compounds in a single phase aqueous solution, as well as the separation of the prepolymers precipitated therefrom and their subsequent use for the production of plastics and plastic articles obtainable therefrom. In particular, the invention relates to respective methods for enzyme-catalyzed preparation of prepolymers with polyamide-type bonding structure for the production of polyamide-based plastics.