Polyamide master batch as well as preparation method and application thereof

Abstract

The invention discloses a polyamide master batch, the polyamide master batch contains polyamide, an X component phosphorus antioxidant and a Y component hindered amine antioxidant, and the weight ratio of the X component to the Y component is 0.005-5.000. The polyamide master batch contains few foreign matters, and can be used for preparing polyamide fibers and fiber products with good oxidation resistance and few foreign matters after being diluted by matrix polyamide slices.

Description

Technical Field

[0001] The present invention relates to a polyamide masterbatch, in particular to a polyamide masterbatch with uniformly dispersed antioxidant and less foreign matter. Background Art

[0002] Polyamide fiber is one of the earliest synthetic fibers to enter industrial production worldwide. Polyamide boasts excellent mechanical properties, chemical resistance, abrasion resistance, and moisture absorption, making it widely used in clothing, rubber skeleton materials, airbags, and military products. However, polyamide is susceptible to oxidative degradation during synthesis, product preparation, storage, and use, resulting in molecular weight loss and color changes. Therefore, improving the thermal and oxidative stability of polyamide has long been a focus of research.

[0003] Adding antioxidants is an effective means of preventing oxidative degradation of polyamide. Antioxidant polyamide masterbatches are often prepared by mixing antioxidant-added polyamide masterbatches with conventional polyamide. Chinese patent CN114957982A discloses a nylon antioxidant masterbatch. Nylon powder, an antioxidant, a light stabilizer, and a lubricant are first mixed to form a premix. This premix is ​​then fed into an extruder and extruded into pellets to produce the nylon antioxidant masterbatch. The total weight of the nylon powder, antioxidant, light stabilizer, and lubricant is 100 parts, with 2-6 parts of antioxidant, 7-10 parts of light stabilizer, 8-12 parts of lubricant, and the balance being nylon powder. This nylon antioxidant masterbatch can prevent or mitigate oxidation during processing. However, when antioxidants are added in large quantities, compatibility between the antioxidant and nylon is poor, leading to the formation of foreign matter. Furthermore, the antioxidant effect of any antioxidant is limited, and yellowing cannot be effectively prevented during processing. Therefore, it is necessary to improve the compatibility of antioxidants and nylon in masterbatch, improve the ratio of compound antioxidants, and improve the antioxidant effect while maintaining the original mechanical properties of the product. Summary of the Invention

[0004] The object of the present invention is to provide a polyamide masterbatch with less foreign matter and a preparation method thereof. The polyamide masterbatch can be diluted with a matrix polyamide slice and used to make a polyamide product with good oxidation resistance, less foreign matter and high strength.

[0005] The technical solution of the present invention is:

[0006] A polyamide masterbatch contains polyamide, a phosphorus antioxidant (component X) and a hindered amine antioxidant (component Y), wherein the weight ratio of the component X to the component Y is 0.005 to 5.000.

[0007] The X component preferably accounts for 500 to 50,000 ppm of the polyamide masterbatch.

[0008] The polyamide masterbatch preferably further contains a hindered phenol antioxidant as component Z, and the weight ratio of component X to the sum of component Y and component Z is preferably 0.003 to 2.000.

[0009] The Z component preferably accounts for 100,000 ppm or less of the polyamide masterbatch.

[0010] The weight ratio of -NH- groups in the polyamide masterbatch to the sum of the X component, the Y component, and the Z component is preferably 0.3 to 15.0.

[0011] The present invention also discloses two methods for preparing polyamide masterbatches. One method is to add a phosphorus-based antioxidant (X component) and a hindered amine antioxidant (Y component) at any stage of the polyamide synthesis process, wherein the weight ratio of the components X to Y is 0.005 to 5.000.

[0012] Another method is to mix polyamide resin, X component phosphorus antioxidant and Y component hindered amine antioxidant, and then use an extruder to granulate to obtain polyamide resin masterbatch, wherein the weight ratio of X component to Y component is 0.005 to 5.000.

[0013] The polyamide masterbatch of the present invention has few foreign matters and can be made into polyamide fibers and fiber products with excellent antioxidant properties after being blended with matrix polyamide chips. DETAILED DESCRIPTION

[0014] Elements such as carbon, hydrogen, and nitrogen in the molecular structure of polyamide react chemically with oxygen to generate alkyl radicals, peroxide radicals, and amino radicals. Alkyl radicals can further oxidize to peroxide radicals. However, peroxide radicals are unstable, and some can further generate hydroperoxides, accelerating the oxidative decomposition of polyamide. Consequently, polyamide is susceptible to oxidative degradation during thermal processing and use, resulting in a decrease in relative molecular weight and color change. Improving the thermo-oxidative stability of polyamide has long been a focus of research. Adding antioxidants is an effective means of preventing oxidation in polymers. Currently, commonly used antioxidants for polymers include phosphorus-containing compounds, hindered phenolic compounds, and hindered amine compounds. However, adding large amounts of antioxidants to polyamide can affect its compatibility with the polyamide, leading to the formation of foreign matter in the polyamide masterbatch, which in turn affects the oxidation resistance and mechanical properties of the final fiber and fiber products. Therefore, there is a need to improve existing antioxidant formulations to reduce the formation of foreign matter in polyamide masterbatch.

[0015] The present invention provides a polyamide masterbatch that exhibits both antioxidant properties and low foreign matter content. The masterbatch comprises polyamide, a phosphorus-based antioxidant (X component), and a hindered amine antioxidant (Y component). The phosphorus-based antioxidant (X component) can capture hydroperoxides, while the hindered amine antioxidant (Y component) can simultaneously capture peroxide radicals, alkyl radicals, and amino radicals. Through the synergistic effect of components X and Y, the polyamide masterbatch of the present invention exhibits excellent antioxidant properties.

[0016] In addition to the aforementioned effects, component X can also inhibit oxidation of component Y in air, thereby improving the antioxidant efficiency of component Y and effectively preventing yellowing of the polyamide masterbatch and the final polyamide product. To achieve this effect, the present invention limits the weight ratio of component X to component Y to 0.005 to 5.000. Under the same conditions as the content of component Y, when the weight ratio of component X to component Y is greater than 5.000, after the tasks of capturing hydroperoxides and inhibiting the oxidation of component Y are completed, some component X will still remain alone. This not only increases the production cost of the polyamide masterbatch, but also a large amount of component X will become foreign matter. After the polyamide masterbatch is diluted with the matrix polyamide chips, it is easy to increase viscosity and form gels during subsequent processing, which causes significant wear and tear on processing equipment. The strength of the resulting product (such as fiber or film) is too low, making the production and processing of the product difficult. When the weight ratio of component X to component Y is less than 0.005, the excessive amount of component X cannot fully capture hydroperoxides and inhibit the oxidation of component Y, resulting in a weakened antioxidant effect of the overall antioxidant and an inability to inhibit yellowing of the polyamide masterbatch. Considering the cost, processability, and yellowing inhibition effect of the polyamide masterbatch, the weight ratio of component X to component Y is preferably 0.010 to 2.000.

[0017] In addition to meeting the aforementioned weight ratio of component X to component Y, further controlling the content of component X can achieve a better antioxidant effect. This is because if the content of component X is too low, it cannot effectively capture hydroperoxides, and thus cannot effectively inhibit the yellowing of polyamide products made from the diluted polyamide masterbatch. If the content of component X is too high, a large amount of component X will also become foreign matter in the polyamide masterbatch, and after dilution with the matrix polyamide chips, it will easily increase viscosity and produce gels during subsequent processing, causing significant wear and tear on processing equipment, reducing the strength of the resulting product (such as fiber or film), and increasing the difficulty of product production and processing. Based on this, the proportion of component X in the polyamide masterbatch of the present invention is preferably 500 to 50,000 ppm, and more preferably 500 to 10,000 ppm.

[0018] To obtain a polyamide masterbatch with excellent antioxidant properties, the content of the Y component cannot be too low, otherwise it will not be able to completely capture peroxide free radicals, alkyl free radicals, and amino free radicals. The content of the Y component cannot be too high, otherwise it will increase the production cost of the polyamide masterbatch. Excessive Y component will reduce the interaction between polyamide molecules, resulting in a decrease in the viscosity of the polyamide product during processing after the polyamide masterbatch is diluted with the matrix polyamide chips. In the present invention, the proportion of the Y component in the polyamide masterbatch is preferably 5000-100000ppm, more preferably 10000-50000ppm.

[0019] The present invention has no particular limitation on the phosphorus-based antioxidant of the X component. From the perspectives of improving the antioxidant properties of the polyamide masterbatch, maintaining hygroscopicity, and processability, poly(dipropylene glycol) phenyl phosphite (antioxidant PDP), bis(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphate (antioxidant PEP36), tris(2,4-di-tert-butylphenyl) phosphite (antioxidant IR168), bis(2,4,6-tri-tert-butylphenyl) pentaerythritol diphosphite (antioxidant 633), tetra(2,4-di-tert-butylphenyl) phosphite (antioxidant IR168), and tetra(2,4-di-tert-butylphenyl) phosphite (antioxidant IR168). At least one of tris(2,4-di-tert-butylphenol)phosphite (antioxidant IR168) and bis(2,4-dicumylphenyl)pentaerythritol diphosphite (antioxidant 9228).

[0020] The present invention has no particular limitation on the hindered amine antioxidant of the Y component. From the perspectives of improving the antioxidant properties of the polyamide masterbatch, maintaining hygroscopicity, and processability, preferred are poly{[6-[(1,1,3,3-tetramethylbutyl)amino]]-1,3,5-triazine-2,4-[(2,2,6,6-tetramethyl-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]} (HS944), poly(4-hydroxyethyl-2,2,6,6-tetramethyl-1-piperidinethanol) succinate (UV622), and 2,2,6,6-tetramethyl-1-(undecanyloxy)-4-piperidinol carbonate (LA-81). , 1,3,5-triazine-2,4,6-triamine-NN"'-[1,2-ethanediylbis[[[4,6-bis[butyl(1,2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,5-triazin-2-yl]imino]3,1-propanediyl]]-bis[N'-N"-dibutyl-N',N"-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)] (HALS119), N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,3-benzenedicarboxamide (UV660), and bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (TINUVIN770).

[0021] To fully capture alkyl and amino radicals in polyamide and effectively inhibit oxidative yellowing of polyamide masterbatches and their products, the polyamide masterbatch of the present invention preferably also contains a hindered phenolic antioxidant, component Z. However, the content of component Z should be limited, as this increases the production cost of the polyamide masterbatch. Excessive component Z will oxidize in air to form quinone compounds, which can easily cause yellowing of the polyamide masterbatch and its products. In the present invention, component Z preferably accounts for less than 100,000 ppm of the polyamide masterbatch, and more preferably less than 50,000 ppm.

[0022] At the same time, according to the mechanism of action of each antioxidant, in order to suppress the compatibility of the antioxidant and polyamide due to excessive decomposition and cross-linking reaction of each antioxidant component, and taking comprehensive consideration of the cost, strength, and yellowing inhibition effect of the polyamide masterbatch, the present invention also preferably has a weight ratio of the X component to the sum of the Y component and the Z component (X component / (Y component + Z component)) of 0.003 to 2.000, and the total amount of the X component, the Y component, and the Z component preferably accounts for 10,000 ppm to 300,000 ppm of the polyamide masterbatch, thereby suppressing the generation of foreign matter in the polyamide masterbatch.

[0023] The present invention has no particular limitation on the hindered phenol antioxidant of the Z component. From the perspectives of improving the antioxidant properties of the polyamide masterbatch and after dilution, processability, and reducing foreign matter, tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]pentaerythritol ester (antioxidant 1010), β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester (antioxidant 1076), 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene (antioxidant 330), 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-tri At least one of 1,2-dimethyl-2,4,8,10-tetraoxaspiro[5.5]undecane (AO80), 2,2'-methylenebis(4-methyl-6-tert-butylphenol) (antioxidant 2246), 2,6-di-tert-butyl-4-methylphenol (antioxidant BHT), and N,N'-(hexane-1,6-diyl)bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide] (antioxidant 1098).

[0024] While controlling the ratio and content range of antioxidant components X, Y, and Z can effectively exert antioxidant effects, improper addition can also affect the compatibility of the antioxidant with polyamide. The -NH- groups in polyamide form hydrogen bonds with the antioxidant, contributing to compatibility between the polyamide and the antioxidant. The more hydrogen bonds formed, the stronger the interaction and the better the compatibility. Therefore, the weight ratio of -NH- groups to the sum of components X, Y, and Z in the polyamide masterbatch—that is, the value of -NH- / (components X + Y + Z)—needs to be adjusted to ensure compatibility between the polyamide and the antioxidant. If this ratio is too small, the polyamide contains too few -NH- groups relative to the total amount of antioxidant, resulting in fewer hydrogen bonds between the -NH- groups in the polyamide and the antioxidant, a weaker interaction, poor compatibility between the polyamide and the antioxidant, and the formation of foreign matter in the polyamide masterbatch. If this ratio is too large, the total amount of antioxidant is too small relative to the total amount of -NH- groups in the polyamide, and the antioxidant properties of the polyamide masterbatch are not effectively improved. The weight ratio of -NH- groups to the sum of components X, Y, and Z is preferably 0.3 to 15.0.

[0025] The polyamide masterbatch described in the present invention can be a common material in the prior art, such as polyamide 6, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyamide 612, polyamide 46, polyamide 1010, polyamide 54, polyamide 56, polyamide 59, polyamide 510, polyamide 511, polyamide 512, polyamide 513, polyamide 514, polyamide 515, polyamide 516, polyamide 517, polyamide 518, etc.

[0026] The present invention also discloses a preparation method of the polyamide masterbatch. Depending on the adding time, the antioxidant can be added during the polymerization process or can be added by blending.

[0027] The method of adding the antioxidant during the polymerization process refers to adding the phosphorus antioxidant component X and the hindered amine antioxidant component Y at any stage of the polyamide synthesis process, and the weight ratio of the component X to the component Y is 0.005 to 5.000.

[0028] Another blending and adding method is to mix the polyamide resin, the phosphorus antioxidant (component X) and the hindered amine antioxidant (component Y), and then use an extruder to granulate to obtain a polyamide resin masterbatch, wherein the weight ratio of the component X to the component Y is 0.005 to 5.000.

[0029] In the above two adding methods, a hindered phenol antioxidant as component Z may also be added. The weight ratio of component X to the sum of component Y and component Z is preferably 0.003 to 2.000.

[0030] The polyamide masterbatch can be prepared by conventional methods. The present invention provides an example of obtaining a polyamide resin masterbatch by copolymerization:

[0031] (1) preparing a salt solution of aliphatic diamine, aliphatic diacid and ion exchange water, wherein the temperature of the salt solution shall not exceed 60° C. and the concentration of the nylon salt solution shall be between 30% and 70%;

[0032] (2) The obtained brine solution is concentrated and then subjected to polymerization reaction. The reaction is first carried out at 190-260°C and 1.3-2.2 MPa for 1-4 hours, and then the pressure is reduced to normal pressure and the temperature is controlled at 230-285°C. Finally, the reaction is continued at -0.1-0 MPa for 0.5-3 hours, and the pellets are discharged to obtain polyamide resin masterbatch.

[0033] The antioxidant can be added before the salt solution is prepared, before concentration, or before polymerization, or during the polymerization process. In addition, a catalyst, a capping agent, a matting agent, a weathering agent, etc. can also be added during the polymerization process.

[0034] The raw material of the polyamide can be caprolactam, aminoundecanoic acid, laurolactam, or a combination of a dibasic acid and a diamine, wherein the diamine can be one or more of pentamethylenediamine, decanediamine, and hexamethylenediamine; the dibasic acid is selected from one of succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, and octadecanedioic acid, preferably one or more of adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, or octadecanedioic acid.

[0035] The polyamide masterbatch of the invention has less foreign matter, and the fiber and fiber products prepared from the polyamide masterbatch after dilution have good oxidation resistance and mechanical properties.

[0036] The testing method involved in the present invention is as follows:

[0037] 1. Yellowing value

[0038] Polyamide masterbatch and conventional polyamide chips were blended in a ratio of 10:90 and melt-spun at 285°C and 2500 m / s to produce polyamide yarn. The resulting yarn was then stretched to an elongation of 35% to 40% to produce polyamide fiber of type 36T-33f. The polyamide fiber was then formed into a 26-gauge tubular braid, scoured, dried, and then treated at 200°C for 10 minutes. The yellowing value of the tubular braid before and after heat treatment was measured using a Datacolor 650 spectrophotometer (manufactured by Datacolor Asia Pacific (HK) Ltd.).

[0039] 2. Strength

[0040] After the polyamide masterbatch and ordinary polyamide chips are blended in a ratio of 10:90, they are melt-spun at 285°C and 2500m / s to obtain polyamide yarn. The obtained yarn is then stretched to an elongation of 35% to 40% after stretching, to obtain polyamide fiber of variety 36T-33f. The strength of the polyamide fiber is tested by a strength-elongation tester (Tensilon, a tensile testing machine manufactured by Intech). The stress-strain curve is measured at a test speed of 200mm / min and a distance of 200mm between the two clamps. The load at break is read and divided by the initial fineness to calculate the strength. This operation is repeated 5 times using the same standard, and the simple average of the results is calculated.

[0041] 3. Types and contents of antioxidants

[0042] The polyamide masterbatch was dissolved in dimethyl sulfoxide (DMSO) and centrifuged to obtain an antioxidant mixture. The mixture was then analyzed by high-performance liquid chromatography (HPLC) (Agilent 1290 Infinity II, USA), and the type and content of the antioxidants were determined by chromatographic analysis.

[0043] 4. Moisture absorption rate difference ΔMR

[0044] Polyamide masterbatch and ordinary polyamide chips are blended in a ratio of 10:90 and then melt-spun at 285°C and 2500 m / s to obtain polyamide yarn. The obtained yarn is then stretched to have an elongation of 35% to 40% after stretching, thereby obtaining polyamide fiber of variety 36T-33f. Finally, the polyamide fiber is made into a tubular braid (26 needles).

[0045] (1) Select three samples of woven fabric weighing approximately 1 g, place them in a weighing bottle of known mass, and place them in a dryer at 60°C. Remove the bottle cap and allow it to dry for 30 minutes. Then, replace the bottle cap and take out the weighing bottle.

[0046] (2) Place the weighing bottle in a constant temperature and humidity chamber at 20°C and 65% RH. Remove the bottle cap and allow it to equilibrate for 24 hours. Then replace the bottle cap and take out the weighing bottle. Weigh the sample using a precision balance. The mass obtained minus the mass of the weighing bottle is the sample weight W1.

[0047] (3) Place the weighing bottle in a constant temperature and humidity chamber at 30°C and 90% RH, remove the bottle cap, and allow it to equilibrate for 24 hours. Then replace the bottle cap and take out the weighing bottle. Weigh the sample using a precision balance. The mass of the weighed bottle minus the mass of the weighing bottle is the sample weight W2.

[0048] (4) Place the weighing bottle in a dryer at 105°C, remove the bottle cap, and dry for 2 hours. Then, put the bottle cap back on and take it out. After cooling it in a drying dish at room temperature, use the same precision balance to weigh it. The mass obtained minus the mass of the weighing bottle is the sample weight W3.

[0049] (5) Calculation:

[0050] MR1=(W1-W3) / W3

[0051] MR2=(W2-W3) / W3

[0052] The moisture absorption rate difference ΔMR (%) = MR2 - MR1, and the result is the average value of the three samples.

[0053] 5. -NH- content in polyamide masterbatch

[0054] A certain amount of polyamide masterbatch was taken and the antioxidant was removed by filtration with solvent toluene to obtain polyamide. The hydrogen spectrum of the polyamide was tested using H-NMR (AVANCE 600, Bruker, Germany), and the characteristic peaks of the hydrogen element (the characteristic peak of the hydrogen element on -NH- and the characteristic peak of the hydrogen element on -CH2) were found. The content of -NH- in the polyamide was calculated based on the peak area.

[0055] 6. Filter pressure difference ΔP of polyamide masterbatch

[0056] Polyamide masterbatch and standard polyamide chips were blended at a ratio of 10:90 and tested using a small filterability tester (CN-25-05m / m, manufactured by CHUBU KAGAKU KIKAI SEISAKUSHO CO., LTID.). The filter screen had a pore size of 5μm, the test temperature was the melting point of the polyamide + 35°C, and the discharge rate was 10g / min. The pressure before the filter screen 30 minutes after the start of feeding was recorded as the initial pressure P1, and the final pressure P2 was recorded 6 hours after the initial pressure. The 6-hour filter pressure rise was calculated as ΔP = P2 - P1. A smaller ΔPa indicates a lower level of foreign matter in the polyamide masterbatch.

[0057] The abbreviations of the antioxidants involved in the embodiments of the present invention are as follows.

[0058] X ingredient:

[0059] (1) Poly(dipropylene glycol) phenyl phosphite (abbreviated as antioxidant PDP);

[0060] (2) Tris(2,4-di-tert-butylphenyl)phosphite (abbreviated as antioxidant IR168);

[0061] (3) Bis(2,4-dicumylphenyl)pentaerythritol diphosphite (abbreviated as: antioxidant 9228);

[0062] (4) Bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphate (abbreviated as antioxidant PEP36).

[0063] Y ingredient:

[0064] (1) Poly{[6-[(1,1,3,3-tetramethylbutyl)amino]]-1,3,5-triazine-2,4-[(2,2,6,6-tetramethyl-piperidinyl)imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]} (abbreviation: HS944);

[0065] (2) Poly(4-hydroxyethyl-2,2,6,6-tetramethyl-1-piperidinylethanol) succinate (abbreviation: UV622);

[0066] (3) Bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate (abbreviation: TINUVIN770);

[0067] (4) 2,2,6,6-tetramethyl-1-(undecyoxy)-4-piperidinol carbonate (abbreviation: LA-81);

[0068] (5) N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,3-benzenedicarboxamide (abbreviation: UV-660).

[0069] Z ingredient:

[0070] (1) 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione (abbreviated as Antioxidant 1790);

[0071] (2) 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene (abbreviated as antioxidant 330);

[0072] (3) N,N'-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine (abbreviated as antioxidant 1024);

[0073] (4) 3,9-bis[1,1-dimethyl-2-[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane (abbreviation: AO80);

[0074] (5) N,N'-(hexane-1,6-diyl)bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide] (abbreviated as:

[0075] Antioxidant 1098).

[0076] Example 1

[0077] Pentamethylenediamine, adipic acid, and ion-exchanged water were prepared into a 60% saline solution, which was then placed in a concentrator for concentration. Component X (antioxidant PDP) and component Y (HS944) were then added and transferred to a polymerization reactor for polymerization. The reactor temperature was set at 290°C. The temperature was initially raised while maintaining the pressure at 2 MPa. When the reactor temperature reached 250°C, the pressure was released. Once it reached atmospheric pressure, the pressure was reduced and the set temperature was set to 285°C. After 5 minutes, the pressure was reduced to 30 kPa and maintained until the target viscosity was reached. The solution was then discharged and pelletized to produce polyamide resin masterbatch. The final reactor temperature was 285°C. Component X accounted for 1000 ppm of the polyamide masterbatch, and component Y accounted for 9500 ppm. The specific formulation and physical properties are shown in Table 1.

[0078] Examples 2 to 29

[0079] The preparation method was the same as in Example 1, except that the amount and type of antioxidants were varied for polymerization. The specific formulation and physical properties are shown in Tables 1 and 2.

[0080] Example 30

[0081] Polyamide 56 (PA56) chips, component X (antioxidant IR168), component Y (TIVUVIN770), and component Z (antioxidant 1098) were added to a mixer, mixed, and extruded into pellets. Component X accounted for 3,000 ppm of the polyamide composition, component Y accounted for 25,000 ppm of the polyamide composition, and component Z accounted for 25,000 ppm of the polyamide composition. The specific formulation and physical properties are shown in Table 2.

[0082] Examples 31 to 35

[0083] The preparation method is the same as that of Example 30. The specific formula and physical properties are shown in Tables 2 and 3.

[0084] Examples 36 to 39

[0085] The preparation method was the same as in Example 1, except that the amount and type of antioxidant were changed for polymerization. The specific formulation and physical properties are shown in Table 3.

[0086] Comparative Example 1

[0087] The preparation method was the same as in Example 1, without adding any X component, to obtain a polyamide masterbatch. The specific formula and physical properties are shown in Table 3.

[0088] Since no X component antioxidant is added, the yellowing of the fiber and fiber products obtained by diluting the polyamide masterbatch cannot be effectively inhibited.

[0089] Comparative Example 2

[0090] The preparation method was the same as in Example 1, but without adding any Y component, to produce a polyamide masterbatch. The specific formula and physical properties are shown in Table 3.

[0091] Since no Y component antioxidant is added, the yellowing of the fiber and fiber products obtained by diluting the polyamide masterbatch cannot be effectively inhibited.

[0092] Comparative Example 3

[0093] The preparation method was the same as in Example 1 to obtain a polyamide masterbatch. The specific formulation and physical properties are shown in Table 3.

[0094] Since the weight ratio of the sum of component X and component Y is too small, the yellowing of the fiber and fiber products obtained by diluting the polyamide masterbatch cannot be effectively suppressed.

[0095] Comparative Example 4

[0096] The preparation method was the same as in Example 1 to obtain a polyamide masterbatch. The specific formulation and physical properties are shown in Table 3.

[0097] Since the weight ratio of the sum of component X and component Y is too large, the fiber and fiber products obtained by diluting the polyamide masterbatch have low strength, high filtration pressure during processing, and high foreign matter content.

[0098]

[0099]

[0100]

Claims

1. A polyamide masterbatch, characterized by: The polyamide masterbatch contains polyamide, a phosphorus antioxidant (component X) and a hindered amine antioxidant (component Y), and the weight ratio of the component X to the component Y is 0.005-5.

000.

2. The polyamide masterbatch according to claim 1, wherein: The X component accounts for 500 to 50,000 ppm of the polyamide masterbatch.

3. The polyamide masterbatch according to claim 1, wherein: The polyamide masterbatch further contains a hindered phenol antioxidant as component Z, and the weight ratio of component X to the sum of component Y and component Z is 0.003 to 2.

000.

4. The polyamide masterbatch according to claim 3, wherein: The Z component accounts for less than 100,000 ppm of the polyamide masterbatch.

5. The polyamide masterbatch according to claim 3 or 4, characterized in that: The weight ratio of -NH- groups in the polyamide masterbatch to the sum of components X, Y and Z is 0.3 to 15.

0.

6. The method for preparing the polyamide masterbatch according to claim 1, wherein: The phosphorus antioxidant (X component) and the hindered amine antioxidant (Y component) are added at any stage of the polyamide synthesis process, and the weight ratio of the component X to the component Y is 0.005 to 5.

000.

7. The method for preparing the polyamide masterbatch according to claim 1, wherein: The polyamide resin, the phosphorus antioxidant (component X) and the hindered amine antioxidant (component Y) are mixed and then extruded and granulated using an extruder to obtain a polyamide resin masterbatch. The weight ratio of the component X to the component Y is 0.005 to 5.

000.

8. Use of the polyamide masterbatch according to claim 1 in fibers.

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