Polyamide polymers and their preparation methods

Abstract

The present invention provides a polyamide polymer and a preparation method thereof, belonging to the technical field of polymers. Among them, the polyamide polymer is toughened or toughened and compatibilized by a vinyl polyolefin elastomer graft. By weight, the polyamide polymer includes: 100 parts of polyamide, or 110 - 140 parts of polyamide alloy polymer; 5 - 20 parts of vinyl polyolefin elastomer graft; 0.1 - 2 parts of antioxidant; and 0.1 - 2 parts of lubricant; wherein, the vinyl polyolefin elastomer graft is a graft of vinyl polyolefin elastomer and maleic anhydride; the polyamide alloy polymer is selected from any one of the alloy polymers of polyamide and polyolefin, and the alloy polymers of polyamide and glass fiber.

Description

Technical Field

[0001] The invention belongs to the technical field of polymers, and in particular relates to a polyamide polymer and a preparation method thereof, and more specifically relates to a vinyl polyolefin elastomer graft toughened polyamide, a toughened and volume-enhanced polyamide alloy polymer and a preparation method thereof. Background Art

[0002] Polyamide (PA) materials are widely used in industries such as automobiles, electronic appliances, packaging, daily necessities, and toys due to their superior comprehensive performance, low cost, and easy processing. However, polyamide materials have poor toughness, high notch sensitivity, and low heat resistance in low-temperature environments (0°C~-20°C), which limits the further application of polyamide materials. Although the toughening agents currently on the market can improve the impact resistance of PA, these toughening agents are expensive and cannot solve the problem of poor heat resistance of PA. In order to broaden the application scenarios of PA, PA is often blended with other polyolefin materials or fillers to form polyamide alloy polymers, but due to poor compatibility, the application of PA in toughening and capacity expansion is limited. Therefore, a general toughening and capacity expansion material with a suitable price and excellent comprehensive performance is designed. Summary of the invention

[0003] In view of the above problems, the present invention provides a polyamide polymer and a preparation method thereof, in order to at least partially solve the above technical problems. In this regard, the technical solution provided by the present invention is as follows.

[0004] As a first aspect of the present invention, a polyamide polymer toughened or toughened and expanded with a vinyl polyolefin elastomer graft is provided, which comprises, by weight: 100 parts of polyamide, or 110-140 parts of a polyamide alloy polymer; 5-20 parts of a vinyl polyolefin elastomer graft; 0.1-2 parts of an antioxidant and 0.1-2 parts of a lubricant; wherein the vinyl polyolefin elastomer graft is a graft of a vinyl polyolefin elastomer and maleic anhydride; and the polyamide alloy polymer is selected from any one of an alloy polymer of polyamide and polyolefin, and an alloy polymer of polyamide and glass fiber.

[0005] As a second aspect of the present invention, there is provided a method for preparing a polyamide polymer toughened or toughened and compatibilized with a vinyl polyolefin elastomer graft, comprising: mixing 100 parts of polyamide, 5 - 20 parts of vinyl polyolefin elastomer graft, 0.1 - 2 parts of antioxidant, and 0.1 - 2 parts of lubricant evenly, then feeding them into a twin-screw extruder for blending and extrusion granulation to obtain a polyamide toughened with a vinyl polyolefin elastomer graft; or mixing 100 parts of polyamide, 10 - 40 parts of polyolefin or glass fiber, 5 - 20 parts of vinyl polyolefin elastomer graft, 0.1 - 2 parts of antioxidant, and 0.1 - 2 parts of lubricant evenly, then feeding them into a twin-screw extruder for blending and extrusion granulation to obtain a polyamide alloy polymer toughened and compatibilized with a vinyl polyolefin elastomer graft; wherein, the vinyl polyolefin elastomer graft is obtained by grafting reaction of a vinyl polyolefin elastomer and maleic anhydride.

[0006] In the embodiments of the present invention, the vinyl polyolefin elastomer (EPOE) is a non-polar compound, while the polyamide (PA) is a polar compound. When the two are directly blended, the compatibility is poor, and it is difficult to achieve the purpose of toughening polyamide with a vinyl polyolefin elastomer. Aiming at the problem of poor compatibility between the two, the present invention proposes to carry out graft modification on the vinyl polyolefin elastomer. By utilizing the characteristic of the relatively high degree of branching of the vinyl polyolefin elastomer, maleic anhydride is grafted onto its side chains, so that the vinyl polyolefin elastomer contains polar groups, thereby improving the compatibility with polyamide during mixing, and further achieving the purpose of toughening polyamide with the vinyl polyolefin elastomer graft. The obtained polyamide toughened with the vinyl polyolefin elastomer graft has the advantages of excellent mechanical properties, thermal stability, and low cost. In addition, the vinyl polyolefin elastomer graft of the present invention can not only toughen polyamide and improve the disadvantage of poor strength of polyamide, but also improve the compatibility between polyamide and other polymer materials (such as polyolefin or glass fiber), thereby significantly improving the toughness and compatibility of the polyamide alloy polymer formed by polyamide and other polymer materials. Moreover, the preparation methods of the polyamide toughened with the vinyl polyolefin elastomer graft and the polyamide alloy polymer toughened and compatibilized in the present invention are relatively simple, have high repeatability, and low cost, and can be industrially prepared. Detailed implementation mode

[0007] Polyolefin elastomer (POE) is a random copolymer with a high α-olefin content obtained by copolymerization of ethylene and α-olefin under the action of a catalyst. Since the molecular weight distribution index (PDI is generally 1.4-2.1) of polyolefin elastomer (POE) is relatively narrow, the side groups in the molecular structure can form connection points in the molecular structure to play a role of connection and buffering, so that the material can disperse and buffer the impact when it is impacted. However, POE has long side chains and poor compatibility with short-chain polyolefins such as polyethylene and polypropylene, which reduces the application of POE in toughening and capacity-enhancing alloy materials such as polyamides and polyolefins. In addition, the process requirements for the preparation of POE are relatively strict, and there are certain technical barriers in multiple links such as polymerization process, catalysts, and α-olefins, which cannot achieve larger-scale production.

[0008] In view of the current problems of POE, the present invention proposes to use vinyl polyolefin elastomer (EPOE) as raw material, and through grafting modification thereof, give EPOE polar groups, enhance its compatibility with polyamide, as well as with polymer materials such as polypropylene (PP) and polyethylene (PE), thereby achieving the purpose of using vinyl polyolefin elastomer grafts to toughen polyamide, toughen and compatibility polyamide and other polymer materials.

[0009] Specifically, as the first aspect of the present invention, a polyamide polymer toughened or toughened and expanded with a vinyl polyolefin elastomer graft is provided, which comprises, by weight: 100 parts of polyamide or 110-140 parts of polyamide alloy polymer; 5-20 parts of vinyl polyolefin elastomer graft; 0.1-2 parts of antioxidant and 0.1-2 parts of lubricant; wherein the vinyl polyolefin elastomer graft is a graft of vinyl polyolefin elastomer and maleic anhydride; and the polyamide alloy polymer is selected from any one of an alloy polymer of polyamide and polyolefin and an alloy polymer of polyamide and glass fiber.

[0010] In an embodiment of the present invention, vinyl polyolefin elastomer (EPOE) is a non-polar compound, while polyamide (PA) is a polar compound. When the two are directly blended, the compatibility is poor, and it is difficult to achieve the purpose of toughening polyamide with EPOE. In response to this, the present invention proposes grafting maleic anhydride onto EPOE, using maleic anhydride to endow EPOE with polar groups, and then mixing the obtained vinyl polyolefin elastomer graft with polyamide, and the compatibility is significantly improved, thereby achieving the toughening of polyamide with the vinyl polyolefin elastomer graft. Alternatively, mixing the vinyl polyolefin elastomer graft with polyamide and other polymer materials (such as polyolefin or glass fiber) also significantly improves the compatibility, thereby achieving the toughening and compatibilizing of polyamide and other polymer materials with the vinyl polyolefin elastomer graft, and obtaining a polyamide alloy polymer. In addition, compared with POE, EPOE has a higher degree of branching, can be grafted with more maleic anhydride, and the obtained vinyl polyolefin elastomer graft significantly improves the compatibility with polyamide, or significantly improves the compatibility with polyamide and other polymer materials, thereby achieving the purpose of toughening polyamide or toughening and compatibilizing polyamide alloy polymer, and the obtained polyamide or polyamide alloy polymer has excellent mechanical properties and thermal stability.

[0011] Specifically, the polyamide polymer toughened with the vinyl polyolefin elastomer graft, by weight, includes: 100 parts of polyamide, 5-20 parts of vinyl polyolefin elastomer graft, 0.1-2 parts of antioxidant, and 0.1-2 parts of lubricant. Alternatively, the polyamide polymer toughened and compatibilized with the vinyl polyolefin elastomer graft, by weight, includes: 110-140 parts of polyamide alloy polymer (including 100 parts of polyamide, 10-40 parts of polyolefin or glass fiber), 5-20 parts of vinyl polyolefin elastomer graft, 0.1-2 parts of antioxidant, and 0.1-2 parts of lubricant.

[0012] According to an embodiment of the present invention, the vinyl polyolefin elastomer graft is a graft of vinyl polyolefin elastomer (EPOE) and maleic anhydride, wherein the maleic anhydride grafting rate of the vinyl polyolefin elastomer graft is 0.5%-1.4%. Within this range, the grafting rate of maleic anhydride ensures the compatibility between EPOE and polyamide. If the maleic anhydride grafting rate is less than 0.5%, it is likely to result in poor compatibility between EPOE and polyamide and the purpose of toughening cannot be achieved; if the grafting rate of maleic anhydride is greater than 1.4%, the cost will increase and the toughening effect will not be significantly improved. Similarly, within this range, the grafting rate of maleic anhydride also ensures the compatibility between EPOE and polyamide and other polymer materials, thereby achieving the purpose of toughening and compatibilizing polyamide and other polymer materials.

[0013] According to an embodiment of the present invention, vinyl polyolefin elastomer (EPOE), such as that produced by Hefei Zhongke Kele New Materials Co., Ltd., is obtained by polymerization reaction with only ethylene (CH2=CH2) as a single raw material under the catalytic action of a main catalyst and a co-catalyst. The main catalyst is a diimine nickel catalyst or a diimine palladium catalyst. As the sole raw material for synthesizing vinyl polyolefin elastomer, ethylene significantly reduces the cost and technical difficulty of synthesizing EPOE compared with the synthesis of polyolefin elastomer (POE) by copolymerization of ethylene and α-olefin, thereby reducing the cost of toughening polyamide with vinyl polyolefin elastomer graft. Further, the diimine nickel catalyst has the structure shown in formula (1), and a diimine palladium catalyst can also be used. The diimine palladium catalyst has the same structure as the diimine nickel catalyst, and the only difference is that nickel (Ni) is replaced by palladium (Pd).

[0014] Formula (1); wherein, R1 and R8 are each independently selected from any one of hydrogen, C1-C6 alkyl, halogen, halogen-substituted C1-C6 alkyl, nitro, C1-C6 alkoxy, and trifluoromethyl; R2, R7, R9, and R 12 are each independently selected from hydrogen, C1-C6 alkyl, halogen, and halogen-substituted C1-C6 alkyl; R3, R6, R 10 , and R 11 are each independently selected from any one of hydrogen, C1-C6 alkyl, halogen, halogen-substituted C1-C6 alkyl, phenyl, and diphenylmethyl. R4 and R5 are each independently selected from hydrogen, C1-C6 alkyl, C1-C6 haloalkyl, phenyl, and a substituted phenyl of C6-C 30 . X is selected from any one of halogen, C1-C6 alkane, C2-C6 alkene, allyl, and benzyl, and the halogen is selected from Cl or Br.

[0015] According to an embodiment of the present invention, the co-catalyst used in the process of synthesizing EPOE is selected from at least one of alkylaluminoxane, alkylaluminum, phenylaluminum, alkylaluminum chloride, and borate. The molar ratio of the co-catalyst to the diimine nickel catalyst is (1-5000):1, and the molar ratio of the co-catalyst to the diimine palladium catalyst is (1-5000):1. The temperature of the polymerization reaction is 30-150 °C, the pressure of the polymerization reaction is 0.1-3 MPa, and the time of the polymerization reaction is 0.1-78 h.

[0016] According to an embodiment of the present invention, the antioxidant is selected from one or more of pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (antioxidant 1010), tris(2,4-di-tert-butylphenyl) phosphite (antioxidant 168), n-octadecyl 3,5-di-tert-butyl-4-hydroxyphenylpropionate (antioxidant 1076), bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite (antioxidant 9228), and distearyl thiodipropionate (antioxidant DSTDP); the lubricant is selected from at least one of ethylene bisstearamide (EBS) and pentaerythritol stearate (PETS).

[0017] According to an embodiment of the present invention, the melt index of EPOE is 3 - 13 g / 10 min, the number-average molecular weight (M n n) is 100,000 - 200,000, the molecular weight distribution index (PDI = M w w / M n n, M w w being the weight-average molecular weight) is 1.0 - 2.0, the degree of branching is 30 - 60 branches / 1000 carbons, the density is 0.860 - 0.9 g / cm 3 3, and the melting point is 55 - 65 °C. In the embodiment of the present invention, EPOE has a relatively high degree of branching, and a higher grafting rate can be obtained when it is grafted with maleic anhydride, thereby significantly improving the compatibility between EPOE and maleic anhydride. In addition, EPOE has a wide range of melt indices, which can effectively improve the mechanical properties and processing properties of polyamide. The melt index can be selected from 3 - 5 g / 10 min, 5 - 9 g / 10 min, and 9 - 13 g / 10 min. The molecular weight distribution index of EPOE is relatively narrow, and the number-average molecular weight distribution is relatively uniform, which can reduce cracks when subjected to impact, thereby improving the impact strength of polyamide.

[0018] According to an embodiment of the present invention, the polyolefin is selected from polypropylene (PP) or polyethylene (PE). Due to the wide range of melt indices of EPOE, it can also effectively improve the mechanical properties of polyamide and polyolefin. The molecular weight distribution index of EPOE is relatively narrow, and the number-average molecular weight distribution is relatively uniform, which can reduce cracks when subjected to impact, thereby also improving the impact strength of polyamide and polyolefin. Moreover, the branches of EPOE are relatively short, and the molecular structure is more similar to that of polypropylene (PP) and polyethylene (PE), making the toughening and compatibilizing effect of the vinyl polyolefin elastomer graft on PP and PA, or PE and PA better.

[0019] As a second aspect of the present invention, there is provided a method for preparing a polyamide polymer toughened or toughened and compatibilized with a vinyl polyolefin elastomer graft, comprising: mixing 100 parts of polyamide, 5-20 parts of vinyl polyolefin elastomer graft, 0.1-2 parts of antioxidant and 0.1-2 parts of lubricant evenly, and then feeding them into a twin-screw extruder for blending and extrusion granulation to obtain a polyamide toughened with a vinyl polyolefin elastomer graft; or mixing 100 parts of polyamide, 10-40 parts of polyolefin or glass fiber, 5-20 parts of vinyl polyolefin elastomer graft, 0.1-2 parts of antioxidant and 0.1-2 parts of lubricant evenly, and then feeding them into a twin-screw extruder for blending and extrusion granulation to obtain a polyamide alloy polymer toughened and compatibilized with a vinyl polyolefin elastomer graft; wherein the vinyl polyolefin elastomer graft is obtained by grafting reaction of vinyl polyolefin elastomer (EPOE) with maleic anhydride.

[0020] In the embodiments of the present invention, first, the grafting reaction of EPOE and maleic anhydride is carried out to improve the polarity of EPOE. Subsequently, the raw materials required for preparing the toughened polyamide and the toughened and compatibilized polyamide alloy polymer are transported into a twin-screw extruder for blending and extrusion granulation to obtain a polyamide toughened with a vinyl polyolefin elastomer graft, or a polyamide alloy polymer toughened and compatibilized with a vinyl polyolefin elastomer graft. This preparation method is relatively simple, has strong processability and is repeatable.

[0021] According to the embodiments of the present invention, obtaining a vinyl polyolefin elastomer graft comprises: in the presence of zinc hydroxide, an initiator initiates the grafting reaction of EPOE and maleic anhydride. Among them, the grafting rate of EPOE and maleic anhydride is 0.5%-1.4%; the initiator is selected from one or more of benzoyl peroxide (BPO), dicumyl peroxide (DCP), di-tert-butyl peroxide (DTBP), 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane (T101), 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxynonane (301), and bis(tert-butylperoxyisopropyl)benzene (BIPB).

[0022] Specifically, the method for preparing a vinyl polyolefin elastomer graft includes: conveying EPOE, zinc hydroxide, an initiator, and maleic anhydride into a premixer, mixing at 300 - 1000 revolutions per minute for 8 - 16 minutes to obtain a premix; subsequently feeding the obtained premix into a twin-screw extruder, extruding after blending and cooling by the twin-screw extruder, and initiating a grafting reaction on the vinyl polyolefin elastomer (EPOE) chain segment by the initiator during extrusion to graft maleic anhydride, and obtaining a vinyl polyolefin elastomer graft after pelletizing by a pelletizer. The body temperature of the twin-screw extruder is set at 180°C, the temperature of zone 1 is set at 120 ± 10°C, the temperature of zone 2 is set at 180 ± 10°C, the temperature of zone 3 is set at 200 ± 10°C, the temperature of zone 4 is set at 200 ± 10°C, and the rotational speed of the twin-screw extruder is 400 revolutions per minute.

[0023] Specifically, the method for preparing a polyamide toughened by a vinyl polyolefin elastomer graft includes: weighing polyamide, a vinyl polyolefin elastomer graft, an antioxidant, and a lubricant in proportion and conveying them into a premixer, mixing at 800 - 1500 revolutions per minute for 10 - 20 minutes to obtain a premix; subsequently feeding the obtained premix into a twin-screw extruder, and after blending and cooling by the twin-screw extruder, pelletizing by a pelletizer to obtain a polyamide toughened by a vinyl polyolefin elastomer graft; the body temperature of the twin-screw extruder is set at 180°C, the temperature of zone 1 is set at 120 ± 10°C, the temperature of zone 2 is set at 180 ± 10°C, the temperature of zone 3 is set at 200 ± 10°C, the temperature of zone 4 is set at 200 ± 10°C, and the rotational speed of the twin-screw extruder is 500 revolutions per minute.

[0024] Specifically, the method for preparing a polyamide alloy polymer toughened and compatibilized by a vinyl polyolefin elastomer graft includes: weighing polyamide, polyolefin or glass fiber, a vinyl polyolefin elastomer graft, an antioxidant, and a lubricant in proportion and conveying them into a premixer, mixing at 800 - 1500 revolutions per minute for 10 - 20 minutes to obtain a premix; subsequently feeding the obtained premix into a twin-screw extruder, and after blending and cooling by the twin-screw extruder, pelletizing by a pelletizer to obtain a polyamide alloy polymer toughened and compatibilized by a vinyl polyolefin elastomer graft; the body temperature of the twin-screw extruder is set at 180°C, the temperature of zone 1 is set at 120 ± 10°C, the temperature of zone 2 is set at 180 ± 10°C, the temperature of zone 3 is set at 200 ± 10°C, the temperature of zone 4 is set at 200 ± 10°C, and the rotational speed of the twin-screw extruder is 500 revolutions per minute.

[0025] In summary, the present invention uses vinyl polyolefin elastomer grafted with maleic anhydride to toughen polyamide, toughen and compatibilize polyamide and other polymer materials (such as polyolefins or glass fibers), which can not only improve the disadvantages of poor strength of the obtained polyamide and polyamide alloy polymers, but also improve the toughness of polyamide and polyamide alloy polymers, and the thermal stability is also improved.

[0026] The technical solution of the present invention will be further described in detail below in conjunction with specific embodiments.

[0027] Preparation of vinyl polyolefin elastomer (EPOE): Under the N2 atmosphere, a stir bar, 250 equivalents of MAO (methylaluminoxane, used as a cocatalyst and for removing water and other impurities), and 48 mL of n-hexane were added to a 350 mL pressure-resistant bottle. The reaction temperature was adjusted to 100 °C, the pressure of ethylene gas was adjusted, and a dichloromethane solution of 2 mL of diimine nickel catalyst was injected into the pressure bottle. The valve was closed, and the pressure of ethylene gas was adjusted to 20 bar. After reacting for 0.5 h, the reaction was stopped. A 5% methanol hydrochloric acid solution was added to precipitate the solid, and the solid was washed three times with pure methanol and dried to obtain vinyl polyolefin elastomer (EPOE). The melt index of the obtained EPOE was 4.3 g / 10 min, the number-average molecular weight was 136,000, the molecular weight distribution index was 1.97, the degree of branching was 43 branches / 1000 carbons, and the density was 0.893 g / cm 3 and the melting point was 57 °C.

[0028] Specifically, the structure of the diimine nickel catalyst is as follows:

[0029] 。

[0030] Preparation of the grafted product of vinyl polyolefin elastomer: By weight, 100 parts of the above-prepared EPOE, 1.2 parts of maleic anhydride, 0.15 parts of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane (initiator T101), and 0.3 parts of Zn(OH)2 were taken. In the presence of zinc hydroxide (Zn(OH)2), the initiator initiated the grafting reaction of EPOE and maleic anhydride to obtain the maleic anhydride grafted product of vinyl polyolefin elastomer, abbreviated as EPOE-g-MAH, and the measured grafting rate was 0.73%.

[0031] Example 1

[0032] Prepare a polyamide toughened with a vinyl polyolefin elastomer graft by using the amounts of each component shown in Table 1. Among them, in parts by weight, weigh 100 parts of polyamide (PA-YH800), 10 parts of EPOE-g-MAH, 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 0.2 part of antioxidant DSTDP, and 0.2 part of lubricant EBS (P-130). After mixing evenly, feed them into a premixer and mix for 20 minutes at 1500 revolutions per minute to obtain a premixed material. Subsequently, feed the premixed material into a twin-screw extruder, cool it after blending by the twin-screw extruder, and pelletize it through a pelletizer to obtain a polyamide toughened with a vinyl polyolefin elastomer graft. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of the first zone is 120 °C, the temperature of the second zone is 180 °C, the temperature of the third zone is 200 °C, the temperature of the fourth zone is 200 °C, and the main motor speed of the twin-screw extruder is 500 revolutions per minute.

[0033] Example 2

[0034] Prepare a polyamide alloy polymer toughened and compatibilized with a vinyl polyolefin elastomer graft by using the amounts of each component shown in Table 1. Among them, in parts by weight, weigh 100 parts of polyamide (PA-YH800), 20 parts of polypropylene (PP-K7227H), 10 parts of EPOE-g-MAH, 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 0.2 part of antioxidant DSTDP, and 0.2 part of lubricant EBS (P-130). After mixing evenly, feed them into a premixer and mix for 20 minutes at 1500 revolutions per minute to obtain a premixed material. Subsequently, feed the premixed material into a twin-screw extruder, cool it after blending by the twin-screw extruder, and pelletize it through a pelletizer to obtain a polyamide alloy polymer toughened and compatibilized with a vinyl polyolefin elastomer graft. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of the first zone is 120 °C, the temperature of the second zone is 180 °C, the temperature of the third zone is 200 °C, the temperature of the fourth zone is 200 °C, and the main motor speed of the twin-screw extruder is 500 revolutions per minute.

[0035] Comparative Example 1

[0036] Prepare a polyamide material according to the dosage of each component shown in Table 1. Among them, by weight, it includes: 100 parts of polyamide (PA-YH800), 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 0.2 part of antioxidant DSTDP, and 0.2 part of lubricant EBS (P-130). After mixing evenly, it is sent to a premixer and mixed at 1500 revolutions per minute for 20 minutes to obtain a premixed material. Subsequently, the premixed material is fed into a twin-screw extruder, cooled after being blended by the twin-screw extruder, and pelletized by a pelletizer to obtain a polyamide material. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of the first zone is 120 °C, the temperature of the second zone is 180 °C, the temperature of the third zone is 200 °C, the temperature of the fourth zone is 200 °C, and the main machine speed of the twin-screw extruder is 500 revolutions per minute.

[0037] Comparative Example 2

[0038] Prepare a polyamide alloy polymer according to the dosage of each component shown in Table 1. Among them, by weight, it includes: 100 parts of polyamide (PA-YH800), 20 parts of polypropylene (PP-K7227H), 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 0.2 part of antioxidant DSTDP, and 0.2 part of lubricant EBS (P-130). After mixing evenly, it is sent to a premixer and mixed at 1500 revolutions per minute for 20 minutes to obtain a premixed material. Subsequently, the premixed material is fed into a twin-screw extruder, cooled after being blended by the twin-screw extruder, and pelletized by a pelletizer to obtain a polyamide alloy polymer. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of the first zone is 120 °C, the temperature of the second zone is 180 °C, the temperature of the third zone is 200 °C, the temperature of the fourth zone is 200 °C, and the main machine speed of the twin-screw extruder is 500 revolutions per minute.

[0039] Comparative Example 3

[0040] Prepare a polyamide toughened with the toughening agent N413 of Nengzhiguang according to the dosage of each component shown in Table 1. Among them, by weight, it includes: 100 parts of polyamide (PA-YH800), 10 parts of the toughening agent N413 of Nengzhiguang (a toughening agent formed by grafting maleic anhydride on POE, with a grafting rate of 0.4% - 0.8%), 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 0.2 part of antioxidant DSTDP, and 0.2 part of lubricant EBS (P-130). After mixing evenly, it is sent to a premixer and mixed at 1500 revolutions per minute for 20 minutes to obtain a premixed material. Subsequently, the premixed material is fed into a twin-screw extruder, cooled after being blended by the twin-screw extruder, and pelletized by a pelletizer to obtain a polyamide toughened with the toughening agent N413 of Nengzhiguang. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of the first zone is 120 °C, the temperature of the second zone is 180 °C, the temperature of the third zone is 200 °C, the temperature of the fourth zone is 200 °C, and the main machine speed of the twin-screw extruder is 500 revolutions per minute.

[0041] Comparative Example 4

[0042] Prepare a polyamide alloy polymer toughened and compatibilized with Nengzhiguang N413 toughening agent according to the dosage of each component shown in Table 1. Among them, by weight, it includes: 100 parts of polyamide (PA-YH800), 20 parts of polypropylene (PP-K7227H), 10 parts of Nengzhiguang N413 toughening agent, 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 0.2 part of antioxidant DSTDP, and 0.2 part of lubricant EBS (P-130). After mixing evenly, it is sent to a premixer and mixed at 1500 rpm for 20 minutes to obtain a premix. Subsequently, the premix is fed into a twin-screw extruder, cooled after being blended by the twin-screw extruder, and pelletized by a pelletizer to obtain a polyamide alloy polymer toughened and compatibilized with Nengzhiguang N413 toughening agent. Among them, the barrel temperature of the twin-screw extruder is 180 °C, the temperature of zone 1 is 120 °C, the temperature of zone 2 is 180 °C, the temperature of zone 3 is 200 °C, the temperature of zone 4 is 200 °C, and the main machine speed of the twin-screw extruder is 500 rpm.

[0043] Table 1

[0044]

[0045] Test the melt flow rate, density, tensile strength, fracture strain, flexural modulus, and notched impact of the polymers obtained in the above Examples 1-2 and Comparative Examples 1-4. The specific test results are shown in Table 2.

[0046] The test method for the melt flow rate is: adopt the test method of ASTM D1238, the temperature is 275 °C, the weight mass is 5.0 kg, repeat the experiment 3 times, and record the experimental results.

[0047] The methods for tensile strength and fracture strain are: according to the test method of GB / T1040-2018, use a universal tensile testing machine, control the tensile rate at 50 mm / min to conduct a material tensile test, repeat the tensile experiment five times, and record the experimental results.

[0048] The test method for the flexural modulus is: according to the test method of GB / T9341-2008, use a flexural testing machine, set the flexural time at 3 min, repeat the experiment 3 times, and record the experimental results.

[0049] The test method for the notched impact test is: according to the test methods of GB / T1843-2008 and GB / T1043.1-2008, use a cantilever beam and a simply supported beam notched impact testing machine to conduct tests respectively, repeat the experiment five times, and record the experimental results.

[0050] Table 2

[0051]

[0052] As can be seen from Table 2 above, when using the maleic anhydride grafted product of vinyl polyolefin elastomer to toughen polyamide, its performance in terms of tensile strength, impact strength, fracture strain, etc. is comparable to that of the toughened polyamide with the commercially available Nengzhiguang N413 toughening agent (POE grafted maleic anhydride toughening agent) (such as Example 1 and Comparative Example 3). Moreover, after using the maleic anhydride grafted product of vinyl polyolefin elastomer to toughen polyamide, the Vicat softening temperature of the polyamide exceeds that of the toughened polyamide with the commercially available Nengzhiguang N413 toughening agent (POE grafted product), making the applicable range of the maleic anhydride grafted product of vinyl polyolefin elastomer wider. Further, by comparing Example 1 and Comparative Example 1, it can be found that for the polyamide toughened with the maleic anhydride grafted product of vinyl polyolefin elastomer, its flexural modulus and impact strength are greatly improved, indicating that the maleic anhydride grafted product of vinyl polyolefin elastomer as the main modifier not only improves the disadvantage of poor strength of polyamide, but also greatly improves the toughness of the toughened polyamide, and all mechanical properties are comparable to those of the polyamide toughened with the commercially available Nengzhiguang N413 toughening agent (POE grafted maleic anhydride toughening agent), and its thermal stability even exceeds that of the commercially available N413 toughening agent, indicating that the polyamide toughened with the maleic anhydride grafted product of vinyl polyolefin elastomer can meet the usage requirements of engineering plastic parts in fields such as automobiles and has great application prospects. Even further, by comparing Example 2 and Comparative Example 2, after using the maleic anhydride grafted product of vinyl polyolefin elastomer for toughening and compatibilization, the mechanical properties of the obtained alloy polymer of polyamide and polypropylene have been improved, indicating that the maleic anhydride grafted product of vinyl polyolefin elastomer can better improve the compatibility between polyamide and polypropylene, and the toughening and compatibilization performance of the maleic anhydride grafted product of vinyl polyolefin elastomer is slightly higher than that of the Nengzhiguang N413 toughening agent (such as Example 2 and Comparative Example 4).

[0053] Example 3

[0054] Prepare a polyamide alloy polymer toughened and compatibilized with a vinyl polyolefin elastomer graft according to the amounts of each component shown in Table 3. Among them, by weight, weigh 100 parts of polyamide (PA-YH800), 30 parts of glass fiber (GF-988A), 10 parts of EPOE-g-MAH, 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 0.2 part of antioxidant DSTDP, and 0.2 part of lubricant EBS (P-130). After mixing evenly, feed them into a premixer and mix at 1500 revolutions per minute for 20 minutes to obtain a premix. Subsequently, feed the premix into a twin-screw extruder, cool it after blending by the twin-screw extruder, and pelletize it through a pelletizer to obtain a polyamide alloy polymer toughened and compatibilized with a vinyl polyolefin elastomer graft. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of the first zone is 120 °C, the temperature of the second zone is 180 °C, the temperature of the third zone is 200 °C, the temperature of the fourth zone is 200 °C, and the main machine speed of the twin-screw extruder is 500 revolutions per minute.

[0055] Comparative Example 5

[0056] Prepare an alloy polymer of polyamide and glass fiber according to the amounts of each component shown in Table 3. Among them, by weight, it includes: 100 parts of polyamide (PA-YH800), 30 parts of glass fiber (GF-988A), 0.2 part of antioxidant 1010, 0.2 part of antioxidant 168, 0.2 part of antioxidant DSTDP, and 0.2 part of lubricant EBS (P-130). After mixing evenly, feed them into a premixer and mix at 1500 revolutions per minute for 20 minutes to obtain a premix. Subsequently, feed the premix into a twin-screw extruder, cool it after blending by the twin-screw extruder, and pelletize it through a pelletizer to obtain a polymer of polyamide and glass fiber. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of the first zone is 120 °C, the temperature of the second zone is 180 °C, the temperature of the third zone is 200 °C, the temperature of the fourth zone is 200 °C, and the main machine speed of the twin-screw extruder is 500 revolutions per minute.

[0057] Comparative Example 6

[0058] Prepare a polyamide alloy polymer toughened and compatibilized with Nengzhiguang N413 toughening agent according to the dosage of each component shown in Table 3. Among them, by weight, it includes: 100 parts of polyamide (PA-YH800), 30 parts of glass fiber (GF-988A), 10 parts of Nengzhiguang N413 toughening agent, 0.2 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.2 parts of antioxidant DSTDP, and 0.2 parts of lubricant EBS (P-130). After mixing evenly, it is sent to a premixer and mixed at 1500 revolutions per minute for 20 minutes to obtain a premix. Subsequently, the premix is fed into a twin-screw extruder, cooled after being blended by the twin-screw extruder, and pelletized by a pelletizer to obtain a polyamide alloy polymer toughened and compatibilized with Nengzhiguang N413 toughening agent. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of zone 1 is 120 °C, the temperature of zone 2 is 180 °C, the temperature of zone 3 is 200 °C, the temperature of zone 4 is 200 °C, and the main machine speed of the twin-screw extruder is 500 revolutions per minute.

[0059] Comparative Example 7

[0060] Prepare a polyamide alloy polymer toughened and compatibilized with Nengzhiguang N406 toughening agent according to the dosage of each component shown in Table 3. Among them, by weight, it includes: 100 parts of polyamide (PA-YH800), 30 parts of glass fiber (GF-988A), 10 parts of Nengzhiguang N406 (a toughening agent formed by grafting maleic anhydride on POE, with a grafting rate of 0.45%-0.8%), 0.2 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.2 parts of antioxidant DSTDP, and 0.2 parts of lubricant EBS (P-130). After mixing evenly, it is sent to a premixer and mixed at 1500 revolutions per minute for 20 minutes to obtain a premix. Subsequently, the premix is fed into a twin-screw extruder, cooled after being blended by the twin-screw extruder, and pelletized by a pelletizer to obtain a polyamide alloy polymer toughened and compatibilized with Nengzhiguang N406 toughening agent. Among them, the body temperature of the twin-screw extruder is 180 °C, the temperature of zone 1 is 120 °C, the temperature of zone 2 is 180 °C, the temperature of zone 3 is 200 °C, the temperature of zone 4 is 200 °C, and the main machine speed of the twin-screw extruder is 500 revolutions per minute.

[0061] Table 3

[0062]

[0063] Test the melt flow rate, density, tensile strength, fracture strain, flexural modulus, and notched impact of the polymers obtained in the above Example 3 and Comparative Examples 5-7. The specific test results are shown in Table 4.

[0064] Table 4

[0065]

[0066] As shown in Table 4, comparing Example 3 with Comparative Examples 5-7, the alloy polymer of polyamide and glass fiber toughened and compatibilized with the maleic anhydride grafted product of vinyl polyolefin elastomer (i.e., polyamide alloy polymer) has better performance in terms of tensile strength, impact strength, fracture strain, etc. than the alloy polymer of polyamide and glass fiber toughened and compatibilized with commercially available toughening agents N413 and N406 of ENN (which are grafted products of polyolefin elastomer (POE) grafted with maleic anhydride). Moreover, after using the maleic anhydride grafted product of vinyl polyolefin elastomer to toughen and compatibilize polyamide and glass fiber, the Vicat softening temperature of the obtained alloy polymer of polyamide and glass fiber exceeds that of the alloy polymer of polyamide and glass fiber toughened and compatibilized with commercially available toughening agents N413 and N406 of ENN, making the applicable range of the maleic anhydride grafted product of vinyl polyolefin elastomer wider. Further, comparing Example 3 with Comparative Example 5, it is found that after toughening and compatibilizing with the maleic anhydride grafted product of vinyl polyolefin elastomer, the fracture strain and impact strength of the obtained alloy polymer of polyamide and glass fiber are greatly improved. This shows that using the maleic anhydride grafted product of vinyl polyolefin elastomer as the main modifier not only improves the shortcoming of poor fracture strength of the alloy polymer of polyamide and glass fiber, but also greatly improves the toughness of the alloy polymer of polyamide and glass fiber, and all mechanical properties exceed those of the alloy polymer of polyamide and glass fiber toughened with commercially available toughening agents N413 and N406 of ENN (toughening agents formed by POE grafted with maleic anhydride). The alloy polymer of polyamide and glass fiber toughened and compatibilized with the maleic anhydride grafted product of vinyl polyolefin elastomer can meet the usage requirements of engineering plastic parts in fields such as automobiles, has great application prospects, and can be well applied to engineering plastic parts in fields such as automobiles.

[0067] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A polyamide polymer toughened or toughened and compatibilized with a vinyl polyolefin elastomer graft, characterized in that, By weight parts, including: 100 parts of polyamide, or 110 - 140 parts of polyamide alloy polymer; 5 - 20 parts of vinyl polyolefin elastomer graft; 0.1 - 2 parts of antioxidant; and 0.1 - 2 parts of lubricant; Wherein, the vinyl polyolefin elastomer graft is a graft of vinyl polyolefin elastomer and maleic anhydride; The polyamide alloy polymer is selected from any one of the alloy polymers of polyamide and polyolefin, and the alloy polymer of polyamide and glass fiber; Among them, the vinyl polyolefin elastomer is obtained by polymerization reaction using ethylene as a single raw material under the catalysis of a main catalyst and a co-catalyst. The vinyl polyolefin elastomer has a melt index of 3-13 g / 10 min, a number average molecular weight of 100,000-200,000, a molecular weight distribution index of 1.0-2.0, a degree of branching of 30-60 branches / 1000 carbons, and a density of 0.860-0.9 g / cm 3 , and a melting point of 55-65 °C; The maleic anhydride grafting rate of the vinyl polyolefin elastomer graft is 0.5% - 1.4%.

2. The polyamide polymer according to claim 1, characterized in that, The main catalyst is a diimine nickel catalyst or a diimine palladium catalyst.

3. The polyamide polymer according to claim 1, characterized in that, The antioxidant is selected from one or several of pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], tris[2,4-di-tert-butylphenyl] phosphite, n-octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, and distearyl thiodipropionate; The lubricant is selected from at least one of ethylene bisstearamide and pentaerythritol stearate.

4. The polyamide polymer according to claim 1, wherein The polyolefin is selected from polypropylene or polyethylene.

5. A method for preparing a polyamide polymer toughened or toughened and compatibilized by a vinyl polyolefin elastomer graft as described in any one of claims 1-4, characterized in that, The preparation method includes: After uniformly mixing 100 parts of polyamide, 5 - 20 parts of vinyl polyolefin elastomer graft, 0.1 - 2 parts of antioxidant, and 0.1 - 2 parts of lubricant, feeding them into a twin-screw extruder for blending and extrusion granulation to obtain polyamide toughened by vinyl polyolefin elastomer graft; or After uniformly mixing 100 parts of polyamide, 10 - 40 parts of polyolefin or glass fiber, 5 - 20 parts of vinyl polyolefin elastomer graft, 0.1 - 2 parts of antioxidant, and 0.1 - 2 parts of lubricant, feeding them into a twin-screw extruder for blending and extrusion granulation to obtain polyamide alloy polymer toughened and compatibilized by vinyl polyolefin elastomer graft; Wherein, the vinyl polyolefin elastomer graft is obtained by graft reaction of vinyl polyolefin elastomer and maleic anhydride, and the grafting rate of vinyl polyolefin elastomer and maleic anhydride is 0.5% - 1.4%.

6. The preparation method according to claim 5, wherein Obtaining the vinyl polyolefin elastomer graft includes: In the presence of zinc hydroxide, an initiator initiates the graft reaction of the vinyl polyolefin elastomer and the maleic anhydride.

7. The preparation method according to claim 6, characterized in that, The initiator is selected from one or several of benzoyl peroxide, diisopropylbenzene peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxynonane, and bis(tert-butylperoxyisopropyl)benzene.

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