Reactively-extruded glass fiber reinforced pa6 material and preparation method therefor

Abstract

Disclosed in the present invention are a reactively-extruded glass fiber reinforced PA6 material, which is prepared from the following components in parts by weight: 14.8-79.1 parts of hexanolactam, 0.2-2 parts of an auxiliary agent TMI-g, 20-80 parts of glass fibers, 0.3-2 parts of an initiator, 0.2-0.6 parts of an antioxidant, and 0.2-0.6 parts of a light stabilizer. The glass fiber reinforced PA6 material is prepared by using a method of reactive extrusion anionic ring-opening polymerization of hexanolactam. In the present invention, a TMI-g material is used as a catalyst and a compatibilizer, wherein TMI is used as a catalyst for the anionic polymerization reaction of hexanolactam, and can initiate the ring-opening polymerization of hexanolactam in the presence of an alkaline anionic initiator; and maleic anhydride itself has good compatibility with the glass fibers. Therefore, TMI-g enables hexanolactam to be tightly polymerized and crystallized around the glass fibers, thereby obtaining a modified PA6 material with good performance.

Description

A reactive extruded glass fiber reinforced PA6 material and its preparation method Technical Field

[0001] The present invention relates to the field of polymer materials, and in particular to a reaction-extruded glass fiber reinforced PA6 material and a preparation method thereof. Background Art

[0002] Nylon 6 is one of the most widely used engineering plastics. PA6 boasts high crystallinity, a high melting point, excellent mechanical properties, good impact resistance, wear resistance, and self-lubrication, making it suitable for a wide range of engineering plastic parts. Conventional glass fiber-reinforced PA6 is produced by blending molten PA6 and glass fiber using a twin-screw extruder. However, molten PA6 has a high viscosity, and the maximum glass fiber addition ratio is around 50%. Furthermore, this process is a simple physical blending process, resulting in a weak bond between the glass fiber and the PA6 matrix, making phase separation prone.

[0003] Summary of the Invention

[0004] In view of this, the present invention provides a reaction-extruded glass fiber reinforced PA6 material and a preparation method thereof to solve the problems raised in the above-mentioned background technology. A glass fiber reinforced PA6 material is prepared by the reaction-extrusion anionic ring-opening polymerization of caprolactam, and a homemade TMI-g material is used as a catalyst and compatibilizer, so that caprolactam is tightly polymerized and crystallized around the glass fiber, thereby obtaining a modified material with excellent performance.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] In one aspect, the present invention discloses a reaction-extruded glass fiber reinforced PA6 material, which is prepared from the following components in parts by weight:

[0007] 14.8-79.1 parts of caprolactam

[0008] Additive TMI-g 0.2-2 parts

[0009] Glass fiber 20-80 parts

[0010] 0.3-2 parts initiator

[0011] 0.2-0.6 parts of antioxidant

[0012] Light stabilizer 0.2-0.6 parts.

[0013] As a further solution of the present invention: the caprolactam is a crystalline raw material with a purity of 99.0% or more.

[0014] As a further solution of the present invention: the preparation method of the auxiliary agent TMI-g is as follows:

[0015] Under nitrogen protection, at 78°C-83°C, 3-isopropyl-dimethylbenzyl isocyanate and maleic anhydride were mixed in a mass ratio of 1:(1-3), heated to melt and stirred for 20-30 hours, and cooled to crystallize to obtain the additive TMI-g.

[0016] As a further solution of the present invention: the glass fiber is at least one of continuous glass fiber and chopped glass fiber.

[0017] As a further embodiment of the present invention: the initiator is at least one of sodium hydroxide, initiator C10, and initiator C1.

[0018] As a further solution of the present invention: the antioxidant is at least one of a histamine-receptive antioxidant and a phosphite.

[0019] As a further solution of the present invention: the light stabilizer is at least one of a histamine light stabilizer and a hindered phenol light stabilizer.

[0020] Another aspect of the present invention discloses a method for preparing the reaction-extruded glass fiber reinforced PA6 material as described in any one of the above, comprising the following steps:

[0021] The components are weighed according to parts by weight, and caprolactam, initiator, antioxidant and light stabilizer are fed into the main feeding port of the twin-screw extruder, the auxiliary agent TMI-g is fed into the side feeding port of the twin-screw extruder, and glass fiber is fed into the side feeding glass fiber port of the twin-screw extruder, and the glass fiber-reinforced PA6 material is obtained by reaction extrusion; the temperature of the first zone of the twin-screw extruder is 160°C-200°C, the second zone is 210-230°C, the third zone is 220-240°C, the fourth zone is 220-240°C, and the fifth zone is 210-230°C.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention prepares a glass fiber reinforced PA6 material by a method of reactive extrusion anionic ring-opening polymerization of caprolactam. The present invention proposes a self-made TMI-g material for the first time. TMI serves as a catalyst for the anionic polymerization reaction of caprolactam and can initiate the ring-opening polymerization of caprolactam in the presence of an alkaline anionic initiator. Maleic anhydride itself has good compatibility with glass fiber. TMI-g can serve as both a catalyst and a compatibilizer, allowing caprolactam to be tightly polymerized and crystallized around the glass fiber, thereby obtaining a modified material with excellent performance.

[0024] Since the viscosity of caprolactam monomer after melting is very low, a high proportion of glass fiber can be added to prepare glass fiber reinforced PA6 materials with a wider range of applications.

[0025] The preparation method of the present invention adds caprolactam and initiator as a main feed, while the additive TMI-g is added as a side feed. This ensures that the caprolactam is fully melted before contacting the catalyst (TMI-g), resulting in more uniform polymerization. Preventing premature contact between the initiator and catalyst prevents rapid polymerization and reduces processing difficulty. Unlike traditional commercial nylon grades, the reactive extrusion preparation process of the present invention offers greater flexibility in adjusting the degree of polymerization, molecular weight, and crystallinity through formulation adjustments, resulting in a wider range of end-product performance and promising broad market applications.

[0026] DETAILED DESCRIPTION

[0027] To facilitate understanding of the present invention, the present invention will be described more fully below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] The specific information of the raw materials used in the following examples and comparative examples is as follows:

[0030] Caprolactam, brand Henan Shenma, purity 99.0%;

[0031] Glass fiber 1: ECS305-3-K (Chongqing International); Glass fiber 2: ECS13-03-508A (China Jushi); Glass fiber 3: Continuous glass fiber-988A (China Jushi);

[0032] Initiator 1: sodium hydroxide; Initiator 2: Initiator C10 (Brüggemann); Initiator 3: Initiator C1 (Brüggemann);

[0033] Antioxidants, antioxidant 1098, antioxidant 168, BASF;

[0034] Light stabilizer 1: UV-3346 (Solvay); Light stabilizer 2: UV-329 (Rianlon); Light stabilizer 3: UV305 (BASF); Light stabilizer 4: Light stabilizer 4050 (BASF);

[0035] 3-Isopropyl-dimethylbenzyl isocyanate and maleic anhydride were purchased from Aladdin Reagent;

[0036] PA6, brand 3250 (Jiangsu Hongsheng).

[0037] All materials are commercially available common products.

[0038] It is understood that the above raw materials and reagents are only examples of some specific embodiments of the present invention, which make the technical solution of the present invention clearer, and do not mean that the present invention can only adopt the above reagents. The specific scope in the claims shall prevail. In addition, the "parts" described in the examples and comparative examples, unless otherwise specified, refer to parts by weight.

[0039] Any range described in the present invention includes the end value and any numerical value between the end values ​​and any sub-range formed by the end value or any numerical value between the end values.

[0040] Example 1

[0041] 67.2 parts of caprolactam, 1 part of additive TMI-g, 30 parts of glass fiber ECS305-3-K, 1 part of initiator sodium hydroxide, 0.2 parts of antioxidant 1098, 0.2 parts of antioxidant 168, and 0.4 parts of light stabilizer UV-3346 were weighed and added to a twin-screw extruder for melt extrusion and granulation to obtain a glass fiber reinforced PA6 material. The caprolactam, initiator, antioxidant 1098, antioxidant 168, and light stabilizer were fed from the main feed port, the glass fiber was fed from the glass fiber port, and the additive TMI-g was fed from the side feed port. The temperatures of the twin-screw extruder zone 1 were 190°C, zone 2 was 220°C, zone 3 was 230°C, zone 4 was 230°C, and zone 5 was 220°C.

[0042] The preparation steps of additive TMI-g are as follows:

[0043] Under nitrogen protection at 80°C, 1 part of 3-isopropyl-dimethylbenzyl isocyanate and 2 parts of maleic anhydride were heated, melted, and stirred for 24 hours, and then cooled and crystallized to obtain the additive TMI-g.

[0044] Example 2

[0045] 46 parts of caprolactam, 1.5 parts of additive TMI-g, 50 parts of glass fiber ECS13-03-508A, 1.5 parts of initiator C10, 0.2 parts of antioxidant 1098, 0.3 parts of antioxidant 168, and 0.5 parts of light stabilizer UV-329 were weighed and added to a twin-screw extruder for melt extrusion and granulation to obtain a glass fiber reinforced PA6 material. The caprolactam, initiator, antioxidant, and light stabilizer were fed from the main feed port, the glass fiber was fed from the glass fiber port, and the additive TMI-g was fed from the side feed port. The temperatures of the twin-screw extruder zone 1 were 190°C, zone 2 was 220°C, zone 3 was 230°C, zone 4 was 230°C, and zone 5 was 220°C.

[0046] The preparation steps of additive TMI-g are as follows:

[0047] Under nitrogen protection at 82°C, 1 part of 3-isopropyl-dimethylbenzyl isocyanate and 1 part of maleic anhydride were heated, melted, and stirred for 25 hours, and cooled to crystallize to obtain the additive TMI-g.

[0048] Example 3

[0049] 27.2 parts of caprolactam, 1.2 parts of additive TMI-g, 70 parts of glass fiber ECS13-03-508A, 0.8 parts of initiator C1, 0.2 parts of antioxidant 1098, 0.2 parts of antioxidant 168, and 0.4 parts of light stabilizer UV-329 were weighed and added to a twin-screw extruder for melt extrusion and granulation to obtain a glass fiber reinforced PA6 material. The caprolactam, initiator, antioxidant, and light stabilizer were added through the main feed port, the glass fiber was fed through the glass fiber port, and the additive TMI-g was added through the side feed port. The temperatures of the twin-screw extruder zone 1 were 200°C, zone 2 was 220°C, zone 3 was 230°C, zone 4 was 220°C, and zone 5 was 220°C.

[0050] Under nitrogen protection at 80°C, 1 part of 3-isopropyl-dimethylbenzyl isocyanate and 2 parts of maleic anhydride were heated, melted, and stirred for 26 hours, and cooled to crystallize to obtain the additive TMI-g.

[0051] Example 4

[0052] 79.1 parts of caprolactam, 0.2 parts of additive TMI-g, 20 parts of continuous glass fiber 988A, 0.3 parts of initiator sodium hydroxide, 0.2 parts of antioxidant 1098, and 0.2 parts of light stabilizer UV305 were weighed and added to a twin-screw extruder for melt extrusion and granulation to obtain a glass fiber reinforced PA6 material. The caprolactam, initiator, antioxidant, and light stabilizer were fed from the main feed port, the continuous glass fiber was fed from the glass fiber port, and the additive TMI-g was fed from the side feed port. The temperatures of the twin-screw extruder zone 1 were 160°C, zone 2 was 210°C, zone 3 was 220°C, zone 4 was 220°C, and zone 5 was 210°C.

[0053] Under nitrogen protection at 78°C, 1 part of 3-isopropyl-dimethylbenzyl isocyanate and 1 part of maleic anhydride were heated, melted, and stirred for 20 hours, and cooled and crystallized to obtain the additive TMI-g.

[0054] Example 5

[0055] 14.8 parts of caprolactam, 2 parts of additive TMI-g, 80 parts of glass fiber ECS13-03-508A, 2 parts of initiator C10, 0.3 parts of antioxidant 1098, 0.3 parts of antioxidant 168, and 0.6 parts of light stabilizer 4050 were weighed and added to a twin-screw extruder for melt extrusion and granulation to obtain a glass fiber reinforced PA6 material. The caprolactam, initiator, antioxidant, and light stabilizer were added from the main feed port, the additive TMI-g was added from the side feed port, and the glass fiber was fed from the glass fiber port. The temperatures of the twin-screw extruder zone 1 were 200°C, zone 2 was 230°C, zone 3 was 240°C, zone 4 was 240°C, and zone 5 was 230°C.

[0056] Under nitrogen protection at 83°C, 1 part of 3-isopropyl-dimethylbenzyl isocyanate and 3 parts of maleic anhydride were heated, melted, and stirred for 30 hours, and cooled and crystallized to obtain the additive TMI-g.

[0057] Comparative Example 1

[0058] 69.2 parts of PA6 3250 (Jiangsu Hongsheng), 30 parts of glass fiber-ECS305-3-K, 0.2 parts of antioxidant 1098, 0.2 parts of antioxidant 168, and 0.4 parts of light stabilizer UV-3346 were weighed and added into a twin-screw extruder for melt extrusion and granulation. PA6, glass fiber, antioxidant and light stabilizer were all fed from the main feeding port, and glass fiber was added from the side feeding glass fiber port. The temperature of the twin-screw extruder zone 1 was 190°C, zone 2 was 220°C, zone 3 was 230°C, zone 4 was 230°C, and zone 5 was 220°C.

[0059] Comparative Example 2

[0060] 49 parts of caprolactam PA6 3250 (Jiangsu Hongsheng), 50 parts of glass fiber ECS13-03-508A, 0.2 parts of antioxidant 1098, 0.3 parts of antioxidant 168, and 0.5 parts of light stabilizer UV-329 were weighed and added into a twin-screw extruder for melt extrusion and granulation. PA6, initiator and light stabilizer were fed from the main feeding port, and glass fiber was added from the side feeding glass fiber port. The temperature of the twin-screw extruder zone 1 was 190°C, zone 2 was 220°C, zone 3 was 230°C, zone 4 was 230°C, and zone 5 was 220°C.

[0061] Comparative Example 3

[0062] 68.2 parts of PA6 3250 (Jiangsu Hongsheng), 30 parts of glass fiber-ECS305-3-K, 0.2 parts of antioxidant 1098, 0.2 parts of antioxidant 168, 0.4 parts of light stabilizer UV-3346, and 1 part of compatibilizer POE-g were weighed and added into a twin-screw extruder for melt extrusion and granulation, wherein PA6, antioxidant, light stabilizer and compatibilizer POE-g were all fed from the main feeding port, and glass fiber was added from the side feeding glass fiber port; the temperature of the twin-screw extruder zone 1 was 190°C, zone 2 was 220°C, zone 3 was 230°C, zone 4 was 230°C, and zone 5 was 220°C.

[0063] Material performance tests of Examples 1-5 and Comparative Examples 1-2: Flame retardancy of the materials was measured according to the UL94 standard, tensile strength was tested according to ISO 527 (test temperature 23°C), flexural strength and flexural modulus were tested according to ISO 178 (test temperature 23°C), and Izod notched impact strength was tested according to ISO 180 (test temperature 23°C). The results are shown in Table 1 below:

[0064] Table 1 Performance test results of the products obtained in various embodiments and comparative examples

[0065] Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 Tensile strength MPa 224 256 261 201 281 163 215 169 Flexural strength MPa 420 56 560 73 646 282 643 122 88 Flexural modulus GPa 12.2 20.0 23.1 10.1 26.7 8.8 14.0 9.2 Izod notched impact strength kJ / m 2 14.2 26.2 26.7 8.4 27.8 7.3 20.89.1

[0066] As can be seen from the above table, the glass fiber reinforced PA6 product prepared by the present invention has higher mechanical properties than the molten glass fiber reinforced nylon product, and the maximum glass fiber content can reach 80%, which has a broader application space.

[0067] Although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A reaction extruded glass fiber reinforced PA6 material, characterized in that: It is prepared from the following components by weight: Caprolactam 14.8-79.1 parts Additive TMI-g 0.2-2 parts Glass fiber 20-80 parts Initiator 0.3-2 parts Antioxidant 0.2-0.6 parts Light stabilizer 0.2-0.6 parts.

2. The reaction extruded glass fiber reinforced PA6 material according to claim 1, characterized in that: The caprolactam is a crystalline raw material with a purity of more than 99.0%.

3. The reaction extruded glass fiber reinforced PA6 material according to claim 1, characterized in that: The preparation method of the auxiliary agent TMI-g is as follows: Under nitrogen protection, at 78°C-83°C, 3-isopropyl-dimethylbenzyl isocyanate and maleic anhydride were mixed in a mass ratio of 1:(1-3), heated to melt and stirred for 20-30 hours, and cooled to crystallize to obtain the additive TMI-g.

4. The reaction extruded glass fiber reinforced PA6 material according to claim 1, characterized in that: The glass fiber is at least one of continuous glass fiber and chopped glass fiber.

5. The reaction extruded glass fiber reinforced PA6 material according to claim 1, characterized in that: The initiator is at least one of sodium hydroxide, initiator C10 and initiator C1.

6. The reaction extruded glass fiber reinforced PA6 material according to claim 1, characterized in that: The antioxidant is at least one of a histamine-receptive antioxidant and a phosphite.

7. The reaction extruded glass fiber reinforced PA6 material according to claim 1, characterized in that: The light stabilizer is at least one of a histamine light stabilizer and a hindered phenol light stabilizer.

8. The method for preparing the reaction extruded glass fiber reinforced PA6 material according to any one of claims 1 to 7, characterized in that: The following steps are involved: The components are weighed according to their weight proportions, caprolactam, initiator, antioxidant and light stabilizer are fed from the main feeding port of the twin-screw extruder, the auxiliary agent TMI-g is fed from the side feeding port of the twin-screw extruder, and glass fiber is fed from the side feeding glass fiber port, and a glass fiber reinforced PA6 material is obtained by reaction extrusion; the temperature of the first zone of the twin-screw extruder is 160°C-200°C, the second zone is 210-230°C, the third zone is 220-240°C, the fourth zone is 220-240°C, and the fifth zone is 210-230°C.