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CN-122011375-A - Preparation method of copolyester amide

CN122011375ACN 122011375 ACN122011375 ACN 122011375ACN-122011375-A

Abstract

The invention discloses a preparation method of copolyester amide, which comprises the following steps of (1) putting diacid and dihydric alcohol into a reaction kettle according to the mol ratio of carboxylic acid groups to alcoholic hydroxyl groups (2.0-2.1), carrying out esterification and dehydration reaction for 2-3 hours at 150-190 ℃, then carrying out reduced pressure distillation to remove redundant dihydric alcohol and byproducts to obtain ester group-containing dicarboxylic acid, (2) putting diacid, the ester group-containing dicarboxylic acid, aliphatic diamine, lactam, a stabilizer, a blocking agent and other auxiliary agents into a salt forming kettle, carrying out polymerization reaction for 3-5 hours at 220-250 ℃ and 1.0-1.8 MPa, vacuumizing to a melt index of 35-40 g/10min, and discharging while the vacuum is hot to obtain the copolyester amide. The invention can control the molecular weight and molecular weight distribution of copolyamide, so that the whole molecular chain structure is uniform, and the synergistic optimization of the performances of polyester and polyamide is realized to the greatest extent.

Inventors

  • GUO HONG
  • MENG HAICHENG

Assignees

  • 上海东睿新材料股份有限公司

Dates

Publication Date
20260512
Application Date
20260206

Claims (9)

  1. 1. A method for preparing a copolyester amide, comprising the steps of: (1) Adding aliphatic dibasic acid and/or aromatic dibasic acid and aliphatic dihydric alcohol or cycloaliphatic dihydric alcohol into a reaction kettle according to the mol ratio (2.0-2.1) of carboxylic acid group to alcohol hydroxyl group, adding an esterification catalyst, and carrying out esterification dehydration reaction for 2-3 hours at 150-190 ℃; (2) The preparation method comprises the steps of (1) putting aliphatic dibasic acid and/or aromatic dibasic acid, the dicarboxylic acid containing ester groups, aliphatic diamine, lactam, stabilizer, end-capping agent and other auxiliary agents into a salifying kettle in proportion, charging nitrogen into the kettle to replace air, gradually heating to 220-250 ℃, and carrying out polymerization reaction for 3-5 h under the pressure of 1.0-1.8 MPa, and vacuumizing to the melt index of 35-40 g/10min after pressure relief; (3) After the reaction is finished, introducing nitrogen to release vacuum, and discharging while the mixture is hot to obtain the copolyester amide; The usage amount of the dicarboxylic acid containing ester groups is 5% -15% of the mole amount of the dicarboxylic acid, the lactam is at least one of cyclic lactams with 6-12 carbon atoms, and the usage amount of the lactam is 40% -50% of the total weight of the raw materials.
  2. 2. The method for producing a copolyester amide according to claim 1, wherein in said step (1), said aliphatic dibasic acid is at least one of 1, 4-succinic acid, 1, 5-glutaric acid, 1, 6-adipic acid, 1, 7-pimelic acid, 1, 8-suberic acid, 1, 9-azelaic acid, 1, 10-sebacic acid, undecanedioic acid and dodecanedioic acid, said aromatic dibasic acid is at least one of phthalic acid, isophthalic acid and terephthalic acid, said aliphatic dibasic alcohol is at least one of 1, 4-butanediol, 1, 5-pentanediol, neopentyl glycol and 1, 6-hexanediol, and said alicyclic dibasic alcohol is at least one of 1, 4-cyclohexanedimethanol, 1, 2-cyclohexanediol and 2-methyl-1, 3-cyclohexanediol.
  3. 3. The method for preparing the seed copolyester amide according to claim 1, wherein the ester group-containing dicarboxylic acid is a ternary copolymerized "ABA" structure ester group-containing dicarboxylic acid, and has the following structure: HOOC-(CH 2 ) m -COO-(CH 2 ) n -OOC-(CH 2 ) m -COOH Wherein n is an integer of 4 to 10, and m is an integer of 4 to 14.
  4. 4. The method for producing a seed copolyester amide according to claim 1, wherein in the step (1), the vacuum degree of reduced pressure distillation is 1 to 100pa, and the distillation temperature exceeds the boiling point of glycol by 10 to 30 ℃.
  5. 5. The method according to claim 1, wherein in the step (2), the molar ratio of the total carboxylic acid groups of the aliphatic dibasic acid and/or aromatic dibasic acid and the ester group-containing dicarboxylic acid to the total amine groups of the aliphatic diamine is (1.00-1.05): 1.
  6. 6. The method for producing a seed copolyester amide according to claim 5, wherein the aliphatic diamine is one or more of 1, 4-butanediamine, 1, 5-pentanediamine, 2-methylpentanediamine, hexanediamine, decanediamine and dodecanediamine.
  7. 7. The preparation method of the copolyester amide according to claim 1, wherein the stabilizer is one or more of a light stabilizer, a heat stabilizer, a hindered phenol antioxidant and a pentaerythritol ester antioxidant, and the amount of the stabilizer is 0.05% -1% of the total weight of the raw materials.
  8. 8. The method for preparing the copolyester amide according to claim 1, wherein the end capping agent is one or more of stearic acid, adipic acid and glacial acetic acid, and the addition amount of the end capping agent is 0.2% -0.5% of the total weight of the raw materials.
  9. 9. The method for preparing the copolyester amide according to claim 1, wherein the other auxiliary agents comprise one or more of reinforcing agents, lubricants, plasticizers, nucleating agents, antistatic agents and delustrants, and the addition amount of the other auxiliary agents is 0.5% -1.5% of the total weight of the raw materials.

Description

Preparation method of copolyester amide Technical Field The invention belongs to the technical field of polyester hot melt adhesives, and particularly relates to a preparation method of copolyester amide for clothing lining cloth, textile fiber and adhesives. Background Polyamide is a generic term for polymers containing recurring amide groups in the molecular backbone, which is a semi-crystalline polymer with high strength, good toughness, excellent wear resistance and corrosion resistance, and is widely used in textile, electronic, mechanical and other industries. The copolyamide is prepared by a copolymerization method of several polyamide monomers, the regularity of macromolecules is reduced by copolymerization, the disorder of intermolecular arrangement is increased, the effects of greatly changing the melting point, the solubility, the crystallinity, the transparency and the like of the polyamide monomers are achieved while the composition and the structure of the polyamide monomers are changed, so that the copolyamide with a series of special properties of low melting point and softening point, good transparency, high bonding strength, good softness and the like is prepared, and the copolyamide is widely applied to the hot melt adhesive industry and is favored in the processes of heat sealing, finishing and the like of clothing lining cloth. However, the copolyamide has the advantages of high molecular polarity, poor dimensional stability caused by extremely easy water absorption, poor water washing resistance and the like when applied to the fields of clothing lining cloth and the like, and the copolyester has the same excellent performance as polyamide, but has low water absorption rate of ester bonds relative to amide bonds, so that the ester bonds can better improve the defect of poor water resistance of the copolyamide and improve the dimensional stability, and the copolyester amide is also an important material by combining the advantages of the two. The copolyester amide is a novel polymer material formed by copolymerizing a polyester chain segment and a polyamide chain segment, has excellent performances of water resistance, flexibility, temperature resistance, high strength and the like of polyester, and is widely applied to the field of polymer industry. For a long time, development of a method for efficiently preparing copolyester amide, realization of parameter control such as ester bond to amide bond ratio, polymer molecular weight and distribution thereof, and the like have been the focus of research in the field. Patent document CN111748092a discloses a method for preparing polyesteramide, wherein the content of diethylene glycol (DEG) in the polyesteramide is controlled to be 0.3-6wt%, and the copolyester is prepared by esterification or transesterification of ethylene glycol and aromatic dicarboxylic acid (or derivatives thereof), and then polycondensation is performed with polyamide monomer. However, the document discloses that the copolyester prepolymer is synthesized by esterification or transesterification at the temperature of 200-270 ℃, and the copolyamide monomer is added to react together at the initial stage of the reaction or in the reaction process, or the copolyamide and the copolyester prepolymer are independently prepared, and then the copolyamide is reacted with the polyamide monomer to generate the copolyamide. However, the molecular weight and molecular weight distribution of the copolyester amide prepared by the method are difficult to control, and the addition mode of the polyamide monomer brings certain difficulty and complexity to the process operation. Patent document CN109134850a discloses a preparation method of polyesteramide and fiber application, which adds dihydric alcohol, terephthalic acid and/or its derivative, diamine and/or its derivative into a reaction vessel, controls the heating program, and makes 90% -100% terephthalic acid and/or its derivative undergo the esterification and acylation reaction to obtain the polyesteramide. However, the method is difficult to realize the proportion of an amide bond to an ester bond in the copolyester amide, the dispersibility of molecular weight distribution causes uneven molecular chain structure, and phenomena such as yarn breakage, yarn breakage and the like occur in the spinning process. Disclosure of Invention The invention provides a preparation method of copolyester amide, which aims to solve the problems that a reaction system is difficult to control, the polymerization degree of an amide chain segment is uncontrollable, the application range of a product is narrow and the like in the existing preparation of copolyester amide. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The preparation method of the copolyester amide comprises the following steps: (1) Adding aliphatic dibasic acid and/or aromatic dibasic acid and aliphatic dihydric alcohol or cycloal