POM composition as well as preparation method and application thereof

Abstract

The invention provides a POM composition as well as a preparation method and application thereof. The POM composition comprises the following components in parts by weight: 100 parts of polyformaldehyde resin; 2 to 6 parts of EVA resin grafted maleic anhydride; 1-3 parts of hydroxyl silicone oil; and 20-30 parts of glass fiber. By adding the EVA grafted maleic anhydride and the hydroxyl silicone oil into the glass fiber reinforced POM composition, the wear resistance of the POM composition can be effectively improved, and the glass fiber reinforced POM composition has relatively good strength and modulus, and is particularly suitable for being applied to materials such as automobile skylight slide rails and automobile seat slide rails.

Description

Technical Field

[0001] The present invention relates to the field of polymer materials, and more specifically, to a POM composition and a preparation method and application thereof. Background Art

[0002] Polyoxymethylene resin (POM resin) has good lubricity and wear resistance and is widely used in industrial equipment, office equipment, automobiles, etc. With the complexity and diversification of various parts, higher requirements are placed on the performance of components, not only requiring good wear resistance, but also requiring high strength and modulus, such as materials for automobile sunroof slides, automobile seat slides, etc.

[0003] Adding glass fiber to POM resin can effectively improve the strength and modulus of POM, but it will significantly reduce the wear resistance of POM and cannot meet the requirements of higher performance. Therefore, the art needs to develop a POM composition with both good mechanical properties and good wear resistance. Summary of the invention

[0004] The purpose of the present invention is to provide a POM composition in order to overcome the defects or shortcomings of the above-mentioned prior art POM materials that cannot have both mechanical properties and wear resistance.

[0005] Another object of the present invention is to provide a method for preparing the POM composition.

[0006] Another object of the present invention is to provide applications of the POM composition.

[0007] To achieve the above object, the present invention adopts the following technical solution:

[0008] A POM composition, comprising the following components calculated in parts by weight:

[0009]

[0010] The invention provides a POM composition. The POM composition is used as a matrix resin, glass fiber is added to enhance mechanical properties, and EVA grafted maleic anhydride and hydroxy silicone oil are added, so that the glass fiber reinforced POM composition has good wear resistance, lower friction coefficient, and high mechanical properties. Specifically, the maleic anhydride group in the EVA grafted maleic anhydride can react with the hydroxyl group of the hydroxy silicone oil for grafting, and the compatibility of the hydroxy silicone oil and the POM resin can be increased, thereby improving the wear resistance and friction coefficient, and having good mechanical properties.

[0011] It should be noted that the content of polyoxymethylene resin in the POM composition of the present invention is preferably not less than 70 wt %.

[0012] It should be noted that the EVA grafted maleic anhydride in the present invention is 2 to 6 parts, specifically 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, 5.5 parts or 6 parts, as well as specific point values ​​between the above points. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0013] The amount of hydroxy silicone oil is 1 to 3 parts, specifically 1 part, 1.2 parts, 1.5 parts, 1.8 parts, 2 parts, 2.2 parts, 2.5 parts, 2.8 parts or 3 parts, as well as specific values ​​between the above points. Due to space limitations and for the sake of simplicity, the specific points included in the range are no longer exhaustively listed in the present invention.

[0014] Furthermore, the POM composition comprises the following components calculated in parts by weight:

[0015]

[0016] Furthermore, the mass ratio of the EVA grafted maleic anhydride and the hydroxy silicone oil is (1.5-3):1, for example but not limited to 1.5:1, 1.8:1, 2:1, 2.2:1, 2.5:1, 2.8:1 or 3:1, etc.

[0017] Furthermore, the mass ratio of the EVA grafted maleic anhydride to the hydroxy silicone oil is (1.8-2.5): 1. Adjusting the mass ratio of the two can further improve the wear resistance and reduce the friction coefficient.

[0018] Furthermore, the content of maleic anhydride in the EVA grafted maleic anhydride is not less than 0.5 wt %.

[0019] Furthermore, the content of maleic anhydride in the EVA grafted maleic anhydride is preferably not higher than 2 wt %.

[0020] Furthermore, the EVA grafted maleic anhydride has a melt flow rate of 1 to 20 g / 10 min at 190° C. and a load of 2.16 kg as tested according to ISO 1133-2022 standard.

[0021] Specifically, the vinyl acetate content of the EVA resin in the EVA grafted maleic anhydride is 20-30wt%.

[0022] Specifically, the determination standard of the vinyl acetate content is ASTM E168-2023.

[0023] Furthermore, the hydroxyl content of the hydroxyl silicone oil is 0.5-3.0 wt%.

[0024] Specifically, the determination standard of the hydroxyl content is GB / T 7383-2020.

[0025] Furthermore, the viscosity of the hydroxy silicone oil is 30 to 110 mm 2 / s.

[0026] Specifically, the viscosity is measured according to GB / T 10247-1988.

[0027] Furthermore, the polyoxymethylene resin has a melt flow rate of 5 to 30 g / 10 min at 190° C. and a load of 2.16 kg as tested according to ISO 1133-2022 standard.

[0028] Furthermore, the average diameter of the glass fiber is 9-12 μm.

[0029] Furthermore, the wear-resistant and noise-reducing POM composition further includes 0.1 to 5 parts of an auxiliary agent.

[0030] Specifically, the auxiliary agent includes but is not limited to one or more of an antioxidant, a formaldehyde absorber, a weathering agent or a color powder.

[0031] The present invention can select commonly used antioxidants according to the prior art, for example, but not limited to, the antioxidant is one or more of hindered phenols, phosphite antioxidants or thioester antioxidants.

[0032] Specifically, the hindered phenol antioxidant is one or more of N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide) (Irganox 1098), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 1010), 1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (Irganox 259), β-(4-hydroxy-3,5-di-tert-butylphenyl)propionic acid n-octadecyl (Irganox 1076) or 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)acrylate]-1,1-dimethyl}-2,4,8,10-tetraoxaspirocycloundecane (ADK AO-80).

[0033] The phosphite antioxidant is one or more of tris(2,4-di-tert-butylphenyl)phosphite (Irganox 168), bis(2,6-di-tert-butyl-4-tolyl) pentaerythritol phosphite (PEP-36) or 627A.

[0034] The thioether antioxidant is one or more of distearyl thiodipropionate, dilauryl thiodipropionate or pentaerythritol dodecapropylthioate.

[0035] The present invention can select commonly used formaldehyde absorbents according to the prior art, for example but not limited to, the formaldehyde absorbent is one or more of allantoin, dicyandiamide or melamine.

[0036] The present invention can select commonly used weathering agents according to the prior art, for example but not limited to, the weathering agent is an ultraviolet absorber and / or a light stabilizer.

[0037] The present invention also provides a method for preparing the above-mentioned POM composition, comprising the following steps:

[0038] The components are mixed uniformly according to proportion, and the POM composition is obtained by melt extrusion, cooling and granulation.

[0039] Specifically, the melt extrusion adopts a twin-screw extruder.

[0040] Specifically, the temperature of zone 1 of the twin-screw extruder is 130-170°C, the temperature of zone 2 is 190-210°C, the temperature of zone 3 is 190-220°C, the temperature of zone 4 is 200-220°C, the temperature of zones 5 to 9 is 190-220°C, and the temperature of zone 10 is 180-200°C; the screw speed of the twin-screw extruder is 250-350rpm.

[0041] The present invention also protects the use of the above-mentioned POM composition in the preparation of automobile accessories, such as automobile sunroof slide rails, automobile seat slide rails and other materials.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The invention provides a POM composition. In a glass fiber reinforced POM resin system, adding EVA grafted maleic anhydride and hydroxy silicone oil can effectively improve the wear resistance and friction coefficient of the POM composition, while having good mechanical properties. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present invention will be described clearly and completely below, but the implementation manner of the present invention is not limited thereto.

[0045] Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0046] 1. The raw materials used in the following examples and comparative examples are as follows:

[0047] Polyoxymethylene resin:

[0048] POM resin 1: M90-44, purchased from Polyplastics Co., Ltd.;

[0049] POM resin 2: M270-44, purchased from Polyplastics Co., Ltd.;

[0050] EVA grafted with maleic anhydride:

[0051] EVA grafted maleic anhydride 1: C250, with a melt flow rate of 1.5 g / 10 min at 190 °C and a load of 2.16 kg, purchased from Dow Chemical;

[0052] EVA grafted maleic anhydride 2: C190, with a melt flow rate of 16 g / 10 min at 190 °C and a load of 2.16 kg, purchased from Dow Chemical;

[0053] EVA grafted maleic anhydride 3: 39E660, with a melt flow rate of 2.5 g / 10 min at 190 °C and a load of 2.16 kg, purchased from Dow Chemical;

[0054] SEBS grafted maleic anhydride: SEBS-g-MAH 7126, purchased from Taiwan Rubber Corporation;

[0055] EVA resin: ELVAX 265, melt flow rate of 3 g / 10 min at 190°C and 2.16 kg load, purchased from Dow Chemical;

[0056] Hydroxy silicone oil:

[0057] Hydroxy silicone oil 1: QLS-203M-A, hydroxyl content of 1.2 wt%, viscosity of 60 mm / s, purchased from Wuxi Quanli Technology Co., Ltd.;

[0058] Hydroxy silicone oil 2: QLS-203M-B, hydroxyl content of 0.8 wt%, viscosity of 100 mm / s, purchased from Wuxi Quanli Technology Co., Ltd.;

[0059] Amino silicone oil: cheersil 8120, amino content 1.0%, viscosity 35 mm / s, purchased from Suzhou Qitian New Materials Co., Ltd.;

[0060] Glass fiber: ECS10-3.0-T445, purchased from Taishan Fiberglass;

[0061] Additives:

[0062] Antioxidant: Irganox 168; commercially available;

[0063] Formaldehyde absorbent: allantoin, commercially available; it should be noted that the same raw materials are used in the parallel experiments of various embodiments and comparative examples.

[0064] 2. The POM compositions described in the examples and comparative examples were prepared according to the formulations in Tables 1 to 2 by the following preparation methods:

[0065] The components are put into a high-speed mixer in proportion and mixed evenly, and the POM composition is obtained by melt-extrusion and cooling and granulation through a twin-screw extruder; the temperature of zone 1 of the twin-screw extruder is 150°C, the temperature of zone 2 is 200°C, the temperature of zone 3 is 205°C, the temperature of zone 4 is 210°C, the temperature of zones 5 to 9 is 205°C, and the temperature of zone 10 is 190°C; the screw speed of the twin-screw extruder is 300rpm.

[0066] 3. Performance Testing

[0067] (1) Specific wear and friction coefficient test: The POM compositions prepared in the examples and comparative examples were tested with reference to JIS K7218-1986, with a rotation speed of 0.8 m / s, a load of 10 N, and a rotation distance of 3 km. Each sample was measured twice and the average value was taken.

[0068] (2) Mechanical property test: The tensile strength of the POM composition prepared in each embodiment and comparative example was tested according to ISO-527-2-2012; and the flexural modulus and flexural strength were tested according to ISO 178-2019.

[0069] Examples 1 to 9 and Comparative Examples 1 to 5

[0070] Table 1 Formulation (unit: weight parts) and properties of POM compositions in Examples 1 to 9

[0071]

[0072]

[0073] Table 2 Formula (unit: weight parts) and properties of POM compositions in Comparative Examples 1 to 5

[0074] Comparative Example 1 2 3 4 5 POM resin 1 100 100 100 100 100 EVA grafted with maleic anhydride 1 / 4 4 / / SEBS grafted with maleic anhydride / / / 4 / EVA resin / / / / 4 Hydroxy silicone oil 1 2 / / 2 2 Amino silicone oil / / 2 / / Fiberglass 25 25 25 25 25 Antioxidants 1 1 1 1 1 Formaldehyde absorbent 1 1 1 1 1 <![CDATA[Specific wear rate (10 -3 mm 3 / N·km)]]> 1438 1266 1157 1002 1364 Friction coefficient 0.234 0.353 0.298 0.224 0.216 Tensile strength(MPa) 132 126 127 122 128 Bending strength(MPa) 183 174 178 163 176 Flexural modulus (MPa) 7645 7552 7532 7210 7432

[0075] The POM composition prepared by the present invention has good wear resistance and good mechanical properties, specifically: the specific wear loss is not higher than 700 10 -3 mm 3 / N·km, friction coefficient not higher than 0.2, tensile strength not lower than 120MPa, flexural strength not lower than 170MPa, flexural modulus not lower than 7250MPa.

[0076] It can be seen from Comparative Example 1 or 2 that if only EVA grafted maleic anhydride or hydroxy silicone oil is added, the wear resistance cannot be effectively improved, and the friction coefficient is significantly higher than that in the embodiment.

[0077] It can be seen from Comparative Example 3 that using other silicone oils to replace the hydroxy silicone oil in the present invention cannot play a good synergistic role, and the comprehensive performance of the prepared POM composition is not significantly improved.

[0078] It can be seen from Comparative Examples 4 and 5 that if other resins grafted with maleic anhydride or EVA resins are used to replace the EVA grafted with maleic anhydride in the present invention, the wear resistance of the prepared POM composition is poor, and the friction coefficient is higher than that in the embodiment.

[0079] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A POM composition, characterized in that: The composition comprises the following components calculated by weight:

2. The POM composition according to claim 1, characterized in that: The composition comprises the following components calculated by weight:

3. The POM composition according to claim 1, characterized in that: The EVA grafted maleic anhydride has a melt flow rate of 1 to 20 g / 10 min at 190° C. and a load of 2.16 kg as tested according to ISO 1133-2022 standard.

4. The POM composition according to claim 1, characterized in that: The vinyl acetate content of the EVA resin in the EVA grafted maleic anhydride is 20-30wt%.

5. The POM composition according to claim 1, characterized in that: The hydroxyl content of the hydroxy silicone oil is 0.5-3.0 wt %.

6. The POM composition according to claim 1, characterized in that: The polyoxymethylene resin has a melt flow rate of 5 to 30 g / 10 min at 190° C. and a load of 2.16 kg as tested according to ISO 1133-2022.

7. The POM composition according to claim 1, characterized in that: The average diameter of the glass fiber is 9-12 μm.

8. The POM composition according to claim 1, characterized in that: It also includes 0.1 to 5 parts of auxiliary agents.

9. A method for preparing the POM composition according to any one of claims 1 to 8, characterized in that: The steps include: The components are mixed uniformly according to proportion, and the POM composition is obtained by melt extrusion, cooling and granulation.

10. Use of the POM composition according to any one of claims 1 to 8 in the preparation of automobile parts.

Images