WO2019137303A1 - Polyamide having high crystallization rate, preparation method therefor and application thereof - Google Patents

Abstract

The present invention provides a polyamide having a high crystallization rate. A crystalline peak width at half maximum ΔT_1/2 of the polyamide is 6-12ºC. The polyamide having the high crystallization rate is composed of a repeating unit formed by dicarboxylic acid and diamine. The polyamide is composed of the following repeating unit derived from the following: (a) aromatic diacid and aliphatic diacid; and (b) 1,10-diaminodecane and aliphatic diamine having the number of carbon atoms of 2-13 in addition to 1,10-diaminodecane, the aromatic diacid being 70-100 mol% of (a); 1,10-diaminodecane being 70-100 mol% of (b). The polyamide having a high crystallization rate in the present invention has a high crystallization rate, shortens the injection molding period of a material, and improves the production efficiency. The present invention also provides a preparation method for the polyamide. The method has simple operations and raw materials which are cheap and easily obtained, and is suitable for large-scale production. No additives such as a nucleating agent for improving the crystalline rate of the polyamide are added, thus having few influences on the basic property of the polyamide.

Description

High crystallization rate polyamide and preparation method and application thereof Technical field

The invention relates to the field of polymer technology, in particular to a high crystallization rate polyamide and a preparation method and application thereof.

Background technique

Polyamide is widely used in the fields of electrical and electronic, automotive, home appliances, sporting goods, etc. due to its excellent mechanical properties, heat resistance, abrasion resistance, chemical resistance and self-lubricating properties. Engineering plastics. High temperature resistant polyamides based on semi-aromatic polyamides have broad application prospects in the electrical and electronic industries due to their higher heat resistance temperature and dimensional stability. The development trend of miniaturization of electrical equipment requires high-temperature polyamides to have a high crystallization rate in order to shorten the molding cycle and reduce molding defects.

Currently, "prepolymerization + solid phase thickening" is the mainstream method for preparing polyamides. In the prior art, the prepolymerized product is usually subjected to a granulation treatment, followed by a solid phase viscosity increasing reaction. The particle morphology of the polyamide prepolymer has an important influence on the structure of the product of the solid phase thickening reaction. For example, Japanese Patent No. JP2000044677, JP2008239908 indicates that the excessively large polymer particles cause a large difference in the degree of surface and internal polymerization, an uneven molecular weight distribution, and a gel generated on the surface of the particles. The uneven structure of the polyamide molecular chain causes the crystallization rate to be slow, which affects the injection molding process. In order to increase the crystallization rate of the polyamide, it is common practice to add 0.1%-5% of the nucleating agent during the blending and extrusion process. However, if the nucleating agent is added in an amount exceeding 0.2%, the mechanical properties and the yellowing resistance of the material may be poor. The effect, and the nucleating agent has limited help in the material crystallization rate increase, can not fundamentally solve the problem of slow material crystallization rate.

Summary of the invention

It is an object of the present invention to overcome the above drawbacks and to provide a polyamide having a high crystallization rate. Another object of the present invention is to provide a process for the preparation of the polyamide.

The invention is achieved by the following technical solutions:

A high crystallization rate polyamide having a crystallization peak half-width ΔT _1/2 of 6-12 °C.

The high crystallization rate polyamide has a nucleating agent content of zero.

The nucleating agent is a substance capable of increasing the crystallization rate of the polyamide, wherein the nucleating agent may be an inorganic nucleating agent and an organic nucleating agent.

The inorganic nucleating agent is kaolin, talc, montmorillonite, graphite, glass fiber, magnesium oxide, aluminum oxide, zinc oxide, silicon dioxide, titanium dioxide, zirconium dioxide, antimony trioxide, calcium carbonate, At least one of calcium fluoride and magnesium sulfate.

The organic nucleating agent is at least one of an adipamide dimer, a polyaryl ether sulfone, a polyphenylene sulfide, a phthalocyanine blue, a phenyl hypophosphite, an acetate, and a carbon fiber.

The high crystallization rate polyamide does not contain any additives such as a nucleating agent capable of increasing the crystallization rate of the polyamide. The high crystallization rate polyamide constitutes a repeating unit from a dicarboxylic acid and a diamine.

The dicarboxylic acid is at least one selected from the group consisting of an aromatic diacid or an aliphatic diacid; and the diamine is at least one selected from the group consisting of aliphatic diamines having 2 to 13 carbon atoms. .

The high crystallization rate polyamide consists of repeating units derived from:

(a) an aromatic diacid and an aliphatic diacid;

(b) 1,10-decanediamine and an aliphatic diamine having 2 to 13 carbon atoms other than 1,10-nonanediamine;

Among them, the aromatic diacid accounts for 70-100 mol% of (a), and the 1,10-decanediamine accounts for 70-100 mol% of (b).

The aliphatic diacid is selected from the group consisting of oxalic acid, malonic acid, 1,4-succinic acid, 1,5-glutaric acid, 1,6-hexanedioic acid, 1,7-pimelic acid, 1 , 8-octanedioic acid, 2-methyl suberic acid, 1,9-sebacic acid, 1,10-sebacic acid, 1,11-undecanedioic acid, 1,12-dodecanedioic acid At least one of 1,13-tridecanedioic acid and 1,14-tetradecanedioic acid; preferably at least one of 1,6-hexanedioic acid and 1,10-sebacic acid.

The aliphatic diamine having 2-13 carbon atoms is selected from the group consisting of ethylenediamine, propylenediamine, carnitine, cadaverine, 2-methylpentanediamine, 1,6-hexanediamine, 1, 7-heptanediamine, 1,8-octanediamine, 2-methyloctanediamine, 2,4,4-trimethylhexamethylenediamine, 5-methyl-nonanediamine, 1,9 At least one of hydrazine diamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecanediamine; preferably 1,6-hexanediamine, 1 At least one of 8-octyldiamine, 1,12-dodecanediamine, and 1,13-tridecanediamine.

The aromatic diacid is terephthalic acid.

A method for preparing a high crystallization rate polyamide, comprising the steps of:

(A) prepolymerization step: adding a dicarboxylic acid, a diamine, a reaction aid to the reaction vessel, heating the reaction vessel, and performing a prepolymerization reaction. After the reaction is completed, the prepolymer is pressurized by the pressure in the reaction vessel. Spraying out;

(B) prepolymer pulverization step: pulverizing the cooled prepolymer, the pulverized prepolymer is a powder granule prepolymer, and the powder granule prepolymer having a particle diameter of less than 80 μm accounts for all powder granule prepolymerization. The weight percentage of the substance is not less than 70%;

(C) Tackifying reaction step: The powdery granular prepolymer is subjected to a viscosity-increasing reaction to obtain a polyamide.

Preferably, in the prepolymer pulverization step, the powdery granular prepolymer having a particle diameter of more than 500 μm accounts for not more than 5% by weight of the total powdery granular prepolymer.

The dicarboxylic acid is at least one selected from the group consisting of an aromatic diacid or an aliphatic diacid; and the diamine is at least one selected from the group consisting of aliphatic diamines having 2 to 13 carbon atoms. .

The high crystallization rate polyamide consists of repeating units derived from:

(a) an aromatic diacid and an aliphatic diacid;

(b) 1,10-decanediamine and an aliphatic diamine having 2 to 13 carbon atoms other than 1,10-nonanediamine;

Among them, the aromatic diacid accounts for 70-100 mol% of (a), and the 1,10-decanediamine accounts for 70-100 mol% of (b).

The aliphatic diacid is selected from the group consisting of oxalic acid, malonic acid, 1,4-succinic acid, 1,5-glutaric acid, 1,6-hexanedioic acid, 1,7-pimelic acid, 1 , 8-octanedioic acid, 2-methyl suberic acid, 1,9-sebacic acid, 1,10-sebacic acid, 1,11-undecanedioic acid, 1,12-dodecanedioic acid At least one of 1,13-tridecanedioic acid and 1,14-tetradecanedioic acid.

The aliphatic diamine having 2-13 carbon atoms is selected from the group consisting of ethylenediamine, propylenediamine, carnitine, cadaverine, 2-methylpentanediamine, 1,6-hexanediamine, 1, 7-heptanediamine, 1,8-octanediamine, 2-methyloctanediamine, 2,2,4-trimethylhexamethylenediamine, 5-methyl-nonanediamine, 1,9 At least one of decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, and 1,13-tridecanediamine.

The aromatic diacid is terephthalic acid.

Preferably, in the prepolymerization step, a nylon salt may be added before heating the reaction vessel; the nylon salt includes hexamethylenediamine adipate, hexamethylenediamine sebacate, hexamethylenediamine 12 At least one of an acid salt, hexamethylenediamine tridecanate, hexamethylenediamine tetradecanoate, and hexamethylenediamine hexadecandioate.

The reaction auxiliary agent is at least one selected from the group consisting of a catalyst and a molecular weight modifier.

The catalyst is added in an amount of 0.02-0.2 wt% based on the total weight of the added dicarboxylic acid, diamine, molecular weight regulator, nylon salt, catalyst; the catalyst is selected from the group consisting of phosphoric acid, phosphorous acid, and secondary Phosphoric acid, phenylphosphonic acid, phenylphosphinic acid, phosphate, phosphite, hypophosphite, phenylphosphonate, phenylphosphinate, triphenyl phosphate, triphenyl phosphite, phosphite At least one

The molecular weight modifier is added in an amount of 0.5 to 2.5% by weight based on the total weight of the dicarboxylic acid, the diamine, the nylon salt, the molecular weight modifier, and the catalyst to be added; the molecular weight modifier is selected from the group consisting of monobasic acid At least one of or one of the monoamines.

The monobasic acid is selected from the group consisting of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutylene. At least one of acid, cyclohexanecarboxylic acid, benzoic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid; preferably at least one of formic acid, acetic acid, and benzoic acid One.

The monoamine is selected from the group consisting of methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, cyclohexylamine, At least one of dicyclohexylamine, aniline, toluidine, diphenylamine, naphthylamine; preferably decylamine and/or benzylamine.

Preferably, there is agitation in the reaction vessel in the prepolymerization step.

Preferably, the tackifying reaction is carried out under vacuum or nitrogen.

Preferably, in the prepolymerization step, the reaction temperature is 210-260 ° C, and the reaction time is 1-3 hours.

The viscosity increasing reaction step, the reaction temperature is 230-260 ° C, the reaction time is 6-16 hours, and the vacuum degree is 50-9000 Pa.

Preferably, the viscosity increasing reaction step comprises a reaction temperature of 245-255 ° C, a reaction time of 8-12 hours, and a vacuum degree of 100-1000 Pa.

a high crystallization rate polyamide prepared by the method for preparing a high crystallization rate polyamide;

The high crystallization rate polyamide is used in the fields of electrical and electronic equipment, automobile parts, office supplies, household goods and the like.

The invention has the following beneficial effects:

The polyamide of the present invention has the advantage of high crystallization rate, and the crystallization peak half-width ΔT _1/2 is 6-12 ° C without adding a nucleating agent or the like which accelerates the crystallization rate of the polyamide, which shortens the material injection molding. Molding cycle to improve production efficiency. The polyamide of the present invention does not contain any additives such as an nucleating agent for increasing the crystallization rate of the polyamide, and does not have any influence on the basic properties of the polyamide. The preparation method of the polyamide of the invention is such that the granular prepolymer having a particle diameter of less than 80 μm accounts for not less than 70% by weight of the particulate prepolymer, so that the heat transfer during the thickening process is more rapid, and the particle surface The heat can quickly diffuse into the interior of the particles, promoting the near-surface polymerization of the particles and inhibiting gel formation on the surface of the particles. The method is simple in operation, cheap and easy to obtain raw materials, and is suitable for mass production.

Detailed ways:

The invention is further illustrated by the following detailed description of the preferred embodiments of the invention, but the embodiments of the invention are not limited by the following examples.

The raw materials used in the invention are all derived from commercially available products;

Example 1-10 Preparation of a high crystallization rate polyamide:

Pre-polymerization step: According to the ratio of Table 1, a weighed dicarboxylic acid, a diamine, a nylon salt is added to an autoclave equipped with a magnetic coupling stirring, a condenser tube, a gas phase port, a feed port, and a pressure explosion port. , benzoic acid, sodium hypophosphite, after vacuuming, filling N ₂ to normal pressure, repeating vacuuming, filling N ₂ process three times, and finally raising the N ₂ pressure to 0.3 MPa. The temperature was raised to 220 ° C over 2 hours with stirring, and the reaction mixture was stirred at 220 ° C for 1 hour, and then the temperature of the reactant was raised to 230 ° C with stirring. The reaction was continued at a constant temperature of 230 ° C and a constant pressure of 2.2 MPa for 2 hours. The pressure was kept constant by removing the formed water, and after the completion of the reaction, it was discharged in a spray state, and the prepolymer was vacuum dried at 80 ° C for 24 hours. .

Prepolymer pulverization step: The prepolymer was placed in a YK-160 type rocking granulator. The screen and drum speed are adjusted to control the particle size of the prepolymer. Thereafter, the prepolymer particles were quickly transferred to a GFG high-efficiency boiling dryer, and the drying temperature was set to 90 ° C and dried for 10 minutes to obtain a particulate prepolymer. The particle size distribution of the powdery particulate prepolymer is shown in Table 1. Among them, the YK-160 type swinging granulator and the GFG high-efficiency boiling dryer are all manufactured by Changzhou Rongsheng Drying Equipment Co., Ltd.

The viscosity-increasing reaction step: the pre-pulverized prepolymer is heated to 150 ° C at a heating rate of 50 ° C / hour; the temperature is raised to 200 ° C at a heating rate of 30 ° C / hour; and the temperature is raised to 230 at a heating rate of 10 ° C / hour. °C; Finally, the temperature was raised to 250 ° C at a heating rate of 5 ° C / hour, the temperature was maintained at a vacuum of 100 Pa, and the obtained polyamide was tested for relative viscosity, melting point and crystallization peak half-width. The results are shown in the table. 1 in.

Comparative Example 1-10 Preparation of Polyamide:

Pre-polymerization step: According to the ratio of Table 1, a weighed dicarboxylic acid, a diamine, a nylon salt is added to an autoclave equipped with a magnetic coupling stirring, a condenser tube, a gas phase port, a feed port, and a pressure explosion port. , benzoic acid, sodium hypophosphite, after vacuuming, filling N ₂ to normal pressure, repeating vacuuming, filling N ₂ process three times, and finally raising the N ₂ pressure to 0.3 MPa. The temperature was raised to 220 ° C over 2 hours with stirring, and the reaction mixture was stirred at 220 ° C for 1 hour, and then the temperature of the reactant was raised to 230 ° C with stirring. The reaction was continued at a constant temperature of 230 ° C and a constant pressure of 2.2 MPa for 2 hours. The pressure was kept constant by removing the formed water. After the completion of the reaction, the prepolymer was vacuum dried at 80 ° C for 24 hours to obtain a preheat. Polymer.

Prepolymer granulation step: 600 g of water was added to 3000 g of prepolymer and mixed well. After discharging, it was placed in a YK-160 type rocking granulator. The particle size of the prepolymer is controlled by adjusting the speed of the screen and the drum. Thereafter, the prepolymer particles were quickly transferred to a GFG high-efficiency boiling dryer, and the drying temperature was set to 90 ° C, and dried for 10 minutes to obtain a particulate prepolymer. The particle size distribution of the particulate prepolymer is shown in Table 1.

The viscosity increasing reaction step: the granulated prepolymer is heated to 150 ° C at a heating rate of 50 ° C / hour; the temperature is raised to 200 ° C at a heating rate of 30 ° C / hour; and then raised to a temperature rising rate of 10 ° C / hour to 230 ° C; Finally, the temperature was raised to 250 ° C at a heating rate of 5 ° C / hour, the temperature was constant, the vacuum was 100 Pa, the viscosity-increasing reaction was carried out, and the obtained polyamide was tested for relative viscosity, melting point and crystallization peak half-width, and the results are listed in in FIG. 1.

standard test:

(1) Relative viscosity (η _r ) test: Refer to the People's Republic of China standard GB12006.1-89, the polyamide viscosity number measurement method for testing. The specific test method is to measure the relative viscosity η _r of the polyamide with a concentration of 0.25 g/dl in 98 wt% concentrated sulfuric acid at 25 ± 0.01 ° C, using the NCY-2 automatic viscometer manufactured by Shanghai Silda Scientific Instrument Co., Ltd. measuring.

(2) Melting point (T _m ) test: The test was carried out in accordance with ASTM D3418-2003, Standard Test Method for Transition Temperatures of Polymers By Differential Scanning Calorimetry. The specific test method is to test the melting point of the sample by using a Perkin Elmer Dimond DSC analyzer; the nitrogen atmosphere has a flow rate of 40 mL/min; the temperature is first raised to 350 ° C at 10 ° C / min, maintained at 350 ° C for 5 min, and then at 10 ° C / The temperature was cooled to 50 ° C, and the temperature was raised to 350 ° C at 10 ° C / min, and the endothermic peak temperature at this time was taken as the melting point Tm.

(3) Crystalline peak width at half maximum (ΔT _1/2 ): The test was carried out in accordance with ASTM D3418-2003, Standard Test Method for Transition Temperatures of Polymers By Differential Scanning Calorimetry. The specific test method is to test the melting point of the sample by using a Perkin Elmer Dimond DSC analyzer; the nitrogen atmosphere has a flow rate of 40 mL/min; the temperature is first raised to 350 ° C at 10 ° C / min, maintained at 350 ° C for 5 min, and then at 10 ° C / Min was cooled to 50 ° C, the exothermic peak onset temperature was set to the melting point T1, and the exothermic peak end temperature was set to the melting point T2, ΔT _1/2 = (T1-T2)/2.

(4) Particle size distribution ratio test: according to the national standard GB/T 20405.3-2006 (Urine absorbent for incontinent: Test method for characteristics of polymer matrix absorbent materials - Part 3: Screening method for particle size distribution Test) to test.

Table 1: Example and Comparative Example and Sample Test Results

Continued Table 1:

Continued Table 1:

As can be seen from Table 1, the polyamide of the present invention has a crystal half-width ΔT _1/2 of 6-12 ° C and an excellent crystallization rate. On the other hand, the polyamide of Comparative Example 1-10 had a crystal half-width ΔT _1/2 12.5-23.5 ° C and a slow crystallization rate.

Claims (14)

1. A high crystallization rate polyamide characterized in that its crystallization peak half-width ΔT1/2 is 6-12 °C.
2. The high crystallization rate polyamide according to claim 1, wherein said high crystallization rate polyamide has a nucleating agent content of zero.
3. The high crystallization rate polyamide according to claim 1, wherein said high crystallization rate polyamide comprises repeating units derived from a dicarboxylic acid and a diamine.
4. The high crystallization rate polyamide according to claim 3, wherein the dicarboxylic acid is at least one selected from the group consisting of an aromatic diacid or an aliphatic diacid; and the diamine is selected from the group consisting of carbon At least one of aliphatic diamines having 2 to 13 atomic numbers.
5. A high crystallization rate polyamide according to claim 4, characterized in that it consists of repeating units derived from:

   (a) an aromatic diacid and an aliphatic diacid;

   (b) 1,10-decanediamine and an aliphatic diamine having 2 to 13 carbon atoms other than 1,10-nonanediamine;

   Among them, the aromatic diacid accounts for 70-100 mol% of (a), and the 1,10-decanediamine accounts for 70-100 mol% of (b).
6. The high crystallization rate polyamide according to claim 5, wherein the aliphatic diacid is selected from the group consisting of oxalic acid, malonic acid, 1,4-succinic acid, 1,5-glutaric acid, 1,6-adipate, 1,7-pimelic acid, 1,8-octanedioic acid, 2-methyloctanedioic acid, 1,9-sebacic acid, 1,10-sebacic acid, 1, At least one of 11-undecanedioic acid, 1,12-dodecanedioic acid, 1,13-tridecanedioic acid, 1,14-tetradecanedioic acid; preferably 1,6-hexane At least one of an acid and 1,10-sebacic acid.
7. The high crystallization rate polyamide according to claim 4, wherein the aliphatic diamine having 2 to 13 carbon atoms is selected from the group consisting of ethylenediamine, propylenediamine, carnitine, cadaverine, 2 -methylpentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 2-methyloctanediamine, 2,2,4-trimethylhexa Methyldiamine, 5-methyl-nonanediamine, 1,9-nonanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecane At least one of the amines; preferably at least one of 1,6-hexanediamine, 1,8-octanediamine, 1,12-dodecanediamine, and 1,13-tridecanediamine.
8. The high crystallization rate polyamide according to claim 5, wherein the aromatic diacid is terephthalic acid.
9. A method for preparing a high crystallization rate polyamide according to any one of claims 1-8, comprising the steps of:

   (A) prepolymerization step: adding a dicarboxylic acid, a diamine, a reaction aid to the reaction vessel, heating the reaction vessel, and performing a prepolymerization reaction. After the reaction is completed, the prepolymer is pressurized by the pressure in the reaction vessel. Spraying out;

   (B) prepolymer pulverization step: pulverizing the cooled prepolymer, the pulverized prepolymer is a powder granule prepolymer, and the powder granule prepolymer having a particle diameter of less than 80 μm accounts for all powder granule prepolymerization. The weight percentage of the substance is not less than 70%;

   (C) Tackifying reaction step: The powdery granular prepolymer is subjected to a viscosity-increasing reaction to obtain a polyamide.
10. The method for preparing a high crystallization rate polyamide according to claim 9, wherein in the prepolymer pulverizing step, the powdery granular prepolymer having a particle diameter of more than 500 μm accounts for all of the powdery granular prepolymer. The weight percentage does not exceed 5%.
11. The method for preparing a high crystallization rate polyamide according to claim 9 or 10, wherein in the prepolymerization step, a nylon salt may be added before heating the reaction vessel; the nylon salt is selected from a diamine. In the adipate, hexamethylene diamine sebacate, hexamethylene diamine dodecanoate, hexamethylene diamine tridecanoate, hexamethylene diamine tetradecanoate and hexamethylene diamine hexadecanate At least one.
12. The method for producing a high crystallization rate polyamide according to claim 9, 10 or 11, wherein the reaction auxiliary agent is at least one selected from the group consisting of a catalyst and a molecular weight modifier.
13. The method for preparing a high crystallization rate polyamide according to claim 12, characterized in that the addition of the catalyst is based on the total weight of the added dicarboxylic acid, diamine, molecular weight regulator, nylon salt, and catalyst. The amount is 0.02-0.2 wt%, and the catalyst is selected from the group consisting of phosphoric acid, phosphorous acid, hypophosphorous acid, phenylphosphonic acid, phenylphosphinic acid, phosphate, phosphite, hypophosphite, phenylphosphonate, phenylphosphinium. At least one of an acid salt, a triphenyl phosphate, a triphenyl phosphite, a phosphite triester; based on the total weight of the added dicarboxylic acid, diamine, nylon salt, molecular weight regulator, and catalyst The molecular weight modifier is added in an amount of 0.5 to 2.5% by weight, and the molecular weight modifier is at least one selected from the group consisting of at least one of monobasic acids or at least one of monoamines.
14. Use of a high crystallization rate polyamide prepared by the method for producing a high crystallization rate polyamide according to any one of claims 9 to 13, characterized in that the high crystallization rate polyamide is applied to electrical and electronic equipment, automobile parts , office supplies, household goods and other fields.