High-hardness elastomer composition as well as preparation method and application thereof

Abstract

The invention provides a high-hardness elastomer composition as well as a preparation method and application thereof, and the high-hardness elastomer composition comprises the following components in percentage by weight: 89.8-99.9% of a high-hardness elastomer; and 0.001%-4% of an ionic liquid. The high-hardness elastomer composition comprises the high-hardness elastomer and the ionic liquid, polarity and charges exist in the ionic liquid, the ionic liquid and a hard-segment molecular chain of the high-hardness elastomer can form strong interaction, slippage of the hard-segment molecular chain is reduced, and therefore the problem that the melt strength is low when the high-hardness elastomer is processed can be avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of elastomers, and relates to a high-hardness elastomer composition, a preparation method and an application thereof, and particularly relates to a high-hardness elastomer composition suitable for extrusion molding, a preparation method and an application thereof. Background Art

[0002] Although rubber elastomers are thermosetting, thermoplastics are easier to use in manufacturing. Thermoplastic elastomers usually include a thermoreversible network, mainly divided into six categories: styrene block copolymers, thermoplastic polyolefin elastomers, thermoplastic vulcanizates, thermoplastic polyurethanes, thermoplastic copolyesters and thermoplastic polyamides; Thermoplastic elastomers are usually composed of a hard segment and a soft segment, having excellent properties such as the high elasticity, aging resistance and oil resistance of vulcanized rubber, and environmental protection characteristics such as recyclability for secondary use.

[0003] Thermoplastic elastomers are widely used in various industrial pipes, industrial films, clothing fabrics and cable sheaths, etc. In some special occasions, such as automotive spiral air brake pipes, hydraulic pipes, etc., thermoplastic elastomers with a Shore hardness above 55D are required to provide excellent mechanical properties and burst pressure properties; However, due to the low proportion of the soft segment in high-hardness thermoplastic elastomers, less entanglement between molecular chains, and only weak interactions between molecular chains in the hard segment part that is easy to crystallize after heating and melting, the melt strength is low during processing, and some products with high requirements for dimensional stability often become difficult to mass-produce stably.

[0004] Increasing its molecular weight can improve the melt strength, but increasing the molecular weight will simultaneously cause an increase in the melt viscosity, making it more difficult to process.

[0005] CN105229049A discloses adding a chain terminator with a short molecular chain structure during the synthesis of TPU to disrupt the crystallization of TPU to broaden the processing window. However, this modification method is relatively complex, and the reaction process of the chain terminator is difficult to control, which will lead to differences in the molecular weight and molecular weight distribution of TPU during the actual production process. The reduction of the TPU crystallinity will also cause a long molding time and a decrease in the burst pressure of the pipe.

[0006] CN114031928A discloses adding silica-supported organotin to a small molecule diol chain extender during the synthesis of TPU. Among them, the tin atom forms a coordination bond with the urethane group, increasing the hydrogen bond content of the hard segment, reducing the molecular chain slip generated during melting, and improving the melt strength; However, since the content of organotin will seriously affect the chromaticity and reaction degree of the synthesized polymer, and the particle size of organotin will affect its dispersion and compatibility, it will affect the stability of the product.

[0007] Therefore, in the art, there is a need to develop a high-hardness elastomer composition that can avoid the problem of low melt strength during the processing of high-hardness elastomers and enable large-scale and stable production. Summary of the Invention

[0008] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a high-hardness elastomer composition, a preparation method thereof, and an application thereof.

[0009] To achieve the purpose of this invention, the following technical solutions are adopted:

[0010] In a first aspect, the present invention provides a high-hardness elastomer composition, which, by weight percentage, comprises the following components:

[0011] High-hardness elastomer 89.8% - 99.9%

[0012] Ionic liquid 0.001% - 4%.

[0013] The high-hardness elastomer composition of the present invention comprises a high-hardness elastomer and an ionic liquid. There are polarities and charges in the ionic liquid, which can form strong interactions with the hard-segment molecular chains of the high-hardness elastomer, reduce the slippage of the hard-segment molecular chains, and thus can avoid the problem of low melt strength during the processing of high-hardness elastomers.

[0014] For the high-hardness elastomer composition provided by the present invention, the compatibility between the ionic liquid and the high-hardness elastomer is excellent. The ionic liquid is colorless and transparent and does not cover the body color of the high-hardness elastomer at all.

[0015] In the present invention, the weight percentage of the high-hardness elastomer can be, for example, 89.8%, 89.89%, 90.0%, 91.0%, 92.0%, 93.0%, 94.0%, 94.945%, 95.0%, 95.9%, 96.0%, 97.0%, 98.0%, 98.9%, 99.0%, 99.7%, 99.8%, 99.875%, 99.880%, 99.886%, 99.890%, 99.899%, 99.9%, etc.

[0016] In the present invention, the weight percentage of the ionic liquid can be, for example, 0.001%, 0.01%, 0.02%, 0.025%, 0.05%, 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, etc.

[0017] Preferably, the weight percentage of the ionic liquid is 0.001% - 2%, and more preferably 0.01% - 0.1%.

[0018] Preferably, the high-hardness elastomer includes a thermoplastic elastomer.

[0019] Preferably, the high hardness elastomer includes any one of thermoplastic polyurethane elastomer (TPU), polyether ester elastomer, polyester elastomer or polyamide elastomer, or a combination of at least two thereof. When there are two or more types of high hardness elastomers, the Shore hardnesses of the different types of high hardness elastomers are controlled to be similar or the same.

[0020] Preferably, the Shore hardness of the high hardness elastomer is 55-84D, for example, 55D, 56D, 57D, 58D, 59D, 60D, 61D, 62D, 63D, 64D, 65D, 66D, 67D, 68D, 69D, 70D, 71D, 72D, 73D, 74D, 75D, 76D, 77D, 78D, 79D, 80D, 81D, 82D, 83D, 84D, etc., preferably 60-80D.

[0021] Preferably, the cation of the ionic liquid includes alkyl quaternary ammonium ion, alkyl quaternary phosphonium ion, imidazolium dibromide or sulfonium ion.

[0022] Preferably, the anion of the ionic liquid comprises Cl - 、BF4 - PF6 - 、C3F7COO - CF3SO3 - or (C4F9SO2)N - , preferably PF6 - or C3F7COO - .

[0023] Preferably, the high hardness elastomer composition further comprises additives.

[0024] Preferably, the weight percentage of the additive is 0.095%-10.01%, for example 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0025] Preferably, the additive comprises any one of an organic filler, an inorganic filler, an organic colorant, an inorganic colorant, a pigment, an antioxidant or a UV protection agent, or a combination of at least two thereof.

[0026] Preferably, the Shore hardness of the high-hardness elastomer composition is 55-84D, such as 55D, 56D, 57D, 58D, 59D, 60D, 61D, 62D, 63D, 64D, 65D, 66D, 67D, 68D, 69D, 70D, 71D, 72D, 73D, 74D, 75D, 76D, 77D, 78D, 79D, 80D, 81D, 82D, 83D, 84D, etc.

[0027] Preferably, the melt index of the high-hardness elastomer composition under the conditions of 230 °C and 2.16 kg is 35-185 g / 10 min, such as 35 g / 10 min, 40 g / 10 min, 51 g / 10 min, 52 g / 10 min, 60 g / 10 min, 74 g / 10 min, 80 g / 10 min, 89 g / 10 min, 90 g / 10 min, 100 g / 10 min, 107 g / 10 min, 110 g / 10 min, 119 g / 10 min, 120 g / 10 min, 130 g / 10 min, 140 g / 10 min, 147 g / 10 min, 150 g / 10 min, 165 g / 10 min, 170 g / 10 min, 181 g / 10 min, 185 g / 10 min, etc., and preferably 50-160 g / 10 min.

[0028] In a second aspect, the present invention provides a method for preparing a high-hardness elastomer composition as described in the first aspect, and the preparation method includes the following steps:

[0029] (1) Mix the ionic liquid and the high-hardness elastomer, and dry to obtain a mixture;

[0030] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain composition A;

[0031] (3) Mix a part of composition A obtained in (2) with the high-hardness elastomer and optional additives, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition.

[0032] In the present invention, first, the ionic liquid and a part of the high-hardness elastomer are mixed, extruded, and pelletized to obtain composition A (i.e., the masterbatch), and then a part of composition A is mixed with the high-hardness elastomer to obtain the high-hardness elastomer composition. On the basis of controlling the weight percentage of the ionic liquid to be 0.001%-4%, combined with the process of the present invention, the prepared high-hardness elastomer composition has a suitable melt index and thus has a suitable melt strength.

[0033] Preferably, in step (1), based on the total mass of the ionic liquid and the high-hardness elastomer being 100%, the addition amount of the ionic liquid is 0.1-20%, such as 0.1%, 0.5%, 1%, 3%, 5%, 8%, 10%, 13%, 15%, 18%, 20%, etc.

[0034] Preferably, the addition amount of the partial composition A in step (3) is 1%-20% of the composition A obtained in step (2), such as 1%, 3%, 5%, 8%, 10%, 13%, 15%, 18%, 20%, etc. Preferably, it is 1%-10%.

[0035] Preferably, the addition amount of the high-hardness elastomer in step (3) is such that the weight percentage of the high-hardness elastomer in the high-hardness elastomer composition is 89.8%-99.9%, such as 89.8%, 89.89%, 90.0%, 91.0%, 92.0%, 93.0%, 94.0%, 94.945%, 95.0%, 95.9%, 96.0%, 97.0%, 98.0%, 98.9%, 99.0%, 99.7%, 99.8%, 99.875%, 99.880%, 99.886%, 99.890%, 99.899%, 99.9%, etc., and the weight percentage of the ionic liquid is 0.001%-4%, such as 0.001%, 0.01%, 0.02%, 0.025%, 0.05%, 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, etc.

[0036] Preferably, the addition amount of the additive in step (3) is such that the weight percentage of the additive in the high-hardness elastomer composition is 0.095%-10.01%, such as 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0037] Preferably, the mixing in step (1) includes mixing with a low mixer.

[0038] Preferably, the mixing time in step (1) is 5-15 min, such as 5 min, 10 min, 15 min, etc.

[0039] Preferably, the drying temperature in step (1) is 80-100 °C, such as 80 °C, 90 °C, 100 °C, etc., and the drying time is 4-8 h, such as 4 h, 5 h, 6 h, 7 h, 8 h, etc.

[0040] Preferably, the ratio of the length to the diameter of the twin-screw extruder in step (2) is 44-50, such as 44, 46, 48, 50, etc., the processing temperature is 220-270 °C, such as 220 °C, 230 °C, 250 °C, 270 °C, etc., and the screw rotation speed is 90-400 rpm, such as 90 rpm, 100 rpm, 200 rpm, 300 rpm, 400 rpm, etc., preferably 120-300 rpm.

[0041] Preferably, the ratio of the length to the diameter of the single-screw extruder in step (3) is 28-45, such as 28, 30, 34, 40, 45, etc., the processing temperature is 220-280 °C, such as 220 °C, 230 °C, 250 °C, 280 °C, etc., and the screw rotation speed is 10-50 rpm, such as 10 rpm, 30 rpm, 50 rpm, etc.

[0042] In a third aspect, the present invention provides an application of the high-hardness elastomer composition as described in the first aspect in additive manufacturing, extrusion of films or pipelines.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] (1) The high-hardness elastomer composition of the present invention includes a high-hardness elastomer and an ionic liquid. There are polarities and charges in the ionic liquid, which can form strong interactions with the hard-segment molecular chains of the high-hardness elastomer, reduce the slippage of the hard-segment molecular chains, and thus avoid the problem of low melt strength during the processing of the high-hardness elastomer.

[0045] (2) For the high-hardness elastomer composition provided by the present invention, the compatibility between the ionic liquid and the high-hardness elastomer is excellent. The ionic liquid is colorless and transparent and does not cover the body color of the high-hardness elastomer at all. Description of the Drawings

[0046] Figure 1 It is a drawing of a product obtained by performing fused deposition modeling on the high-hardness elastomer composition provided in Example 6.

[0047] Figure 2 It is a drawing of a product obtained by performing fused deposition modeling on the high-hardness elastomer composition provided in Comparative Example 3. Detailed Embodiments

[0048] The technical solutions of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations on the present invention.

[0049] The raw materials used in the embodiments and comparative examples of the present invention are as follows:

[0050] Thermoplastic polyurethane elastomer: hardness 55D / 60D / 70D / 80D / 84D, all from Wanhua Chemical Co., Ltd.;

[0051] Thermoplastic polyamide elastomer: hardness 60D, from Wanhua Chemical Co., Ltd.;

[0052] Thermoplastic polyester elastomer: hardness 60D, purchased from DSM.

[0053] Example 1

[0054] In this example, a high-hardness elastomer composition is provided and prepared by the following method:

[0055] (1) Select 0.1 part of fully dried ionic liquid, infiltrate it with 99.9 parts of thermoplastic polyurethane elastomer (55D), mix using a low-speed mixer for 10 min, and dry at 80 °C for 4 h to obtain a mixture; wherein, the cation of the ionic liquid is methyl quaternary ammonium ion and the anion is Cl - ;

[0056] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain composition A; wherein, the length-diameter ratio of the twin-screw is 44, the processing temperature is 220 °C, and the screw speed is 90 rpm;

[0057] (3) Mix 1 part of composition A, 98.9 parts of thermoplastic polyurethane elastomer (55D), and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the length-diameter ratio of the single-screw is 28, the processing temperature is 220 °C, and the screw speed is 10 rpm.

[0058] Example 2

[0059] In this example, a high-hardness elastomer composition is provided and prepared by the following method:

[0060] (1) Select 0.2 part of fully dried ionic liquid, infiltrate it with 99.8 parts of thermoplastic polyurethane elastomer (60D), mix using a low-speed mixer for 15 min, and dry at 80 °C for 4 h to obtain a mixture; wherein, the cation of the ionic liquid is methyl phosphonium ion and the anion is Cl - ;

[0061] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain composition A; wherein, the length-diameter ratio of the twin-screw is 45, the processing temperature is 230 °C, and the screw speed is 120 rpm;

[0062] (3) Mix 5 parts of Composition A, 94.9 parts of thermoplastic polyurethane elastomer (60D), and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the ratio of the length to the diameter of the single-screw is 33, the processing temperature is 225 °C, and the screw speed is 15 rpm.

[0063] Example 3

[0064] In this example, a high-hardness elastomer composition is provided and is prepared by the following method:

[0065] (1) Select 0.5 part of fully dried ionic liquid, infiltrate it with 99.5 parts of thermoplastic polyurethane elastomer (70D), mix using a low-speed mixer for 10 min, and dry at 80 °C for 4 h to obtain a mixture; wherein, the cation of the ionic liquid is methyltriphenylphosphonium ion and the anion is Cl - ;

[0066] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the ratio of the length to the diameter of the twin-screw is 48, the processing temperature is 240 °C, and the screw speed is 150 rpm;

[0067] (3) Mix 5 parts of Composition A, 94.9 parts of thermoplastic polyurethane elastomer (70D), and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the ratio of the length to the diameter of the single-screw is 33, the processing temperature is 230 °C, and the screw speed is 20 rpm.

[0068] Example 4

[0069] In this example, a high-hardness elastomer composition is provided and is prepared by the following method:

[0070] (1) Select 10 parts of fully dried ionic liquid, infiltrate it with 90.0 parts of thermoplastic polyurethane elastomer (80D), mix using a low-speed mixer for 15 min, and dry at 80 °C for 6 h to obtain a mixture; wherein, the cation of the ionic liquid is imidazole dibromide and the anion is PF6 - ;

[0071] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the ratio of the length to the diameter of the twin-screw is 50, the processing temperature is 260 °C, and the screw speed is 200 rpm;

[0072] (3) Mix 10 parts of Composition A, 89.9 parts of thermoplastic polyurethane elastomer (80D), and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the ratio of the length to the diameter of the single-screw is 40, the processing temperature is 260 °C, and the screw speed is 15 rpm.

[0073] Example 5

[0074] In this example, a high-hardness elastomer composition is provided and is prepared by the following method:

[0075] (1) Select 20 parts of fully dried ionic liquid, infiltrate it with 80.0 parts of thermoplastic polyurethane elastomer (84D), mix using a low-speed mixer for 5 min, and dry at 80 °C for 8 h to obtain a mixture; wherein, the cation of the ionic liquid is imidazole dibromide and the anion is C3F7COO - ;

[0076] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the ratio of the length to the diameter of the twin-screw is 50, the processing temperature is 270 °C, and the screw speed is 300 rpm;

[0077] (3) Mix 20 parts of Composition A, 79.9 parts of thermoplastic polyurethane elastomer (84D), and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the ratio of the length to the diameter of the single-screw is 45, the processing temperature is 280 °C, and the screw speed is 15 rpm.

[0078] Example 6

[0079] In this example, a high-hardness elastomer composition is provided and is prepared by the following method:

[0080] (1) Select 0.2 parts of fully dried ionic liquid, infiltrate it with 99.8 parts of thermoplastic polyurethane elastomer (70D), mix using a low-speed mixer for 10 min, and dry at 80 °C for 4 h to obtain a mixture; wherein, the cation of the ionic liquid is methyl quaternary ammonium ion and the anion is Cl - ;

[0081] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the ratio of the length to the diameter of the twin-screw is 45, the processing temperature is 240 °C, and the screw speed is 150 rpm;

[0082] (3) Mix 5 parts of Composition A, 94.9 parts of thermoplastic polyurethane elastomer (70D), and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the ratio of the length to the diameter of the single-screw is 33, the processing temperature is 230 °C, and the screw speed is 15 rpm.

[0083] Example 7

[0084] In this example, a high-hardness elastomer composition is provided and is prepared by the following method:

[0085] (1) Select 0.5 part of fully dried ionic liquid, infiltrate it with 99.5 parts of thermoplastic polyurethane elastomer (70D), mix using a low-speed mixer for 15 min, and dry at 80 °C for 4 h to obtain a mixture; wherein, the cation of the ionic liquid is imidazole dibromide and the anion is PF6 - ;

[0086] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the ratio of the length to the diameter of the twin-screw is 45, the processing temperature is 240 °C, and the screw speed is 120 rpm;

[0087] (3) Mix 10 parts of Composition A, 84.9 parts of thermoplastic polyurethane elastomer (70D), and 5.0 parts of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the ratio of the length to the diameter of the single-screw is 40, the processing temperature is 230 °C, and the screw speed is 20 rpm.

[0088] Example 8

[0089] In this example, a high-hardness elastomer composition is provided and is prepared by the following method:

[0090] (1) Select 1 part of fully dried ionic liquid, infiltrate it with 99 parts of thermoplastic polyurethane elastomer (70D), mix using a low-speed mixer for 10 min, and dry at 80 °C for 8 h to obtain a mixture; wherein, the cation of the ionic liquid is imidazole dibromide and the anion is C3F7COO - ;

[0091] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the ratio of the length to the diameter of the twin-screw is 45, the processing temperature is 220 °C, and the screw speed is 90 rpm;

[0092] (3) Mix 10 parts of Composition A, 79.9 parts of thermoplastic polyurethane elastomer (70D), and 10.0 parts of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the length-diameter ratio of the single-screw is 40, the processing temperature is 220 °C, and the screw speed is 15 rpm.

[0093] Example 9

[0094] In this example, a high-hardness elastomer composition is provided and is prepared by the following method:

[0095] (1) Select 0.2 parts of fully dried ionic liquid, infiltrate with 49.8 parts of thermoplastic polyurethane elastomer (60D) and 50 parts of thermoplastic polyamide elastomer (PEBA, 60D), mix using a low-speed mixer for 10 min, and dry at 80 °C for 4 h to obtain a mixture; wherein, the cation of the ionic liquid is methylphosphonium ion and the anion is Cl - ;

[0096] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the length-diameter ratio of the twin-screw is 45, the processing temperature is 230 °C, and the screw speed is 240 rpm;

[0097] (3) Mix 10 parts of Composition A, 44.9 parts of thermoplastic polyurethane elastomer (60D), 50 parts of thermoplastic polyamide elastomer (60D), and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the length-diameter ratio of the single-screw is 33, the processing temperature is 235 °C, and the screw speed is 20 rpm.

[0098] Example 10

[0099] In this example, a high-hardness elastomer composition is provided and is prepared by the following method:

[0100] (1) Select 0.2 parts of fully dried ionic liquid, infiltrate with 33.8 parts of thermoplastic polyurethane elastomer (60D), 33 parts of thermoplastic polyamide elastomer (PEBA, 60D), and 33 parts of thermoplastic polyester elastomer (TPEE, 60D), mix using a low-speed mixer for 10 min, and dry at 80 °C for 4 h to obtain a mixture; wherein, the cation of the ionic liquid is methylphosphonium ion and the anion is Cl - ;

[0101] (2) Mix, extrude, and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the length-diameter ratio of the twin-screw is 45, the processing temperature is 220 °C, and the screw speed is 400 rpm;

[0102] (3) Mix 10 parts of Composition A, 29.9 parts of thermoplastic polyurethane elastomer (60D), 30 parts of thermoplastic polyamide elastomer (60D), 30 parts of thermoplastic polyester elastomer (60D) and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the length-diameter ratio of the single-screw is 40, the processing temperature is 245 °C, and the screw speed is 40 rpm.

[0103] Comparative Example 1

[0104] In this comparative example, a high-hardness elastomer composition is provided and prepared by the following method:

[0105] (1) Select 99.9 parts of thermoplastic polyurethane elastomer (55D), mix, extrude and pelletize using a twin-screw extruder to obtain pellet A; wherein, the length-diameter ratio of the twin-screw is 44, the processing temperature is 220 °C, and the screw speed is 90 rpm;

[0106] (3) Mix 99.9 parts of pellet A and 0.1 part of masterbatch using a low-speed mixer, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the length-diameter ratio of the single-screw is 28, the processing temperature is 220 °C, and the screw speed is 10 rpm.

[0107] Comparative Example 2

[0108] The difference between this comparative example and Example 5 is only that the dosage of Composition A in step (3) is 22 parts.

[0109] Comparative Example 3

[0110] In this comparative example, a high-hardness elastomer composition is provided and prepared by the following method:

[0111] (1) Select 0.2 part of fully dried ionic liquid, infiltrate with 99.8 parts of thermoplastic polyurethane elastomer (70D), mix using a low-speed mixer, the mixing time is 10 min, and dry at 80 °C for 4 h to obtain a mixture; wherein, the cation of the ionic liquid is methyl quaternary ammonium ion and the anion is Cl - ;

[0112] (2) Mix, extrude and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain Composition A; wherein, the length-diameter ratio of the twin-screw is 45, the processing temperature is 240 °C, and the screw speed is 150 rpm;

[0113] (3) Mix 5 parts of Composition A, 94.9 parts of thermoplastic polyurethane elastomer (70D), and 0.1 part of masterbatch using a low-speed mixer, and then use a twin-screw extruder to mix, extrude, and pelletize to obtain Composition B; wherein, the length-diameter ratio of the twin-screw is 45, the processing temperature is 240 °C, and the screw speed is 150 rpm;

[0114] (4) Extrude Composition B using a single-screw extruder to obtain the high-hardness elastomer composition; wherein, the length-diameter ratio of the single-screw is 33, the processing temperature is 230 °C, and the screw speed is 15 rpm.

[0115] The hardness and type of the raw material base (high-hardness elastomer) used in the examples and comparative examples of the present invention, as well as the weight percentage content of the ionic liquid in the obtained high-hardness elastomer composition and the melt index (under the conditions of 230 °C and 2.16 kg) of the high-hardness elastomer composition are shown in Table 1:

[0116] Table 1

[0117]

[0118] The relationship between the melt index and the melt strength can be qualitatively described as melt strength (MS) = 3.54 * 10 5 Δl 2 r0 / MFR 230 , where Δl is the length of the extrudate when the diameter of the extrudate decreases by 50%, r0 is the radius of the extrudate initially emerging from the die orifice, Δl and r0 are used to correct the extrudate characteristics, and MFR 230 refers to the MFR value under the conditions of 230 °C and 2.16 kg. It can be seen that the melt index is negatively correlated with the melt strength. The larger the melt index, the lower the melt strength.

[0119] As can be seen from Table 1, the high-hardness elastomer compositions provided in Examples 1-10 of the present invention all have an appropriate melt index (35-181 g / 10 min), that is, they have appropriate melt strength and are suitable for extrusion molding.

[0120] Compared with Example 1, the melt index of the high-hardness elastomer composition provided in Comparative Example 1 decreased to 14 g / 10 min, and the melt index was too small.

[0121] Compared with Example 5, the melt index of the high-hardness elastomer composition provided in Comparative Example 2 increased to 335 g / 10 min. The melt index was too large and the melt strength was too low, which was not suitable for extrusion molding.

[0122] Compared with Example 6, the melt index of the high-hardness elastomer composition provided in Comparative Example 3 was too large and the melt strength was too low, which was not suitable for extrusion molding.

[0123] The high-hardness elastomer composition provided in Example 6 was subjected to fused deposition modeling (FDM) at a printing temperature of 220°C and a printing speed of 40 mm / s. It was observed that the filament extrusion was stable and uniform, and the surface of the product (such as Figure 1 shown) was smooth.

[0124] The high-hardness elastomer composition provided in Comparative Example 3 was subjected to fused deposition modeling (FDM) at a printing temperature of 220°C and a printing speed of 40 mm / s. It was observed that the filament extrusion was uneven, and melt fracture occurred. The surface of the product (such as Figure 2 shown) was rough and dull.

[0125] In summary, the high-hardness elastomer composition provided by the present invention has an appropriate melt index, can avoid the problem of low melt strength during the processing of high-hardness elastomers, and is suitable for extrusion molding.

[0126] The applicant declares that the present invention uses the above embodiments to illustrate the high-hardness elastomer composition of the present invention, its preparation method and application. However, the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, the equivalent replacement of the raw materials selected for the present invention, the addition of auxiliary components, and the selection of specific methods, etc., all fall within the protection scope and the disclosure scope of the present invention.

Claims

1. A high-hardness elastomer composition, characterized in that, The high-hardness elastomer composition comprises the following components by weight percentage: High-hardness elastomer 89.8%-99.9% Ionic liquid 0.001%-4%.

2. The high-hardness elastomer composition according to claim 1, characterized in that, The weight percentage of the ionic liquid is 0.001%-2%, and further preferably 0.01%-0.1%.

3. The high-hardness elastomer composition according to claim 1 or 2, characterized in that, The high-hardness elastomer includes a thermoplastic elastomer; Preferably, the high-hardness elastomer includes any one or a combination of at least two of thermoplastic polyurethane elastomer, polyether ester elastomer, polyester elastomer or polyamide elastomer; Preferably, the Shore hardness of the high-hardness elastomer is 55-84D, and preferably 60-80D.

4. The high-hardness elastomer composition according to any one of claims 1-3, characterized in that, The cation of the ionic liquid includes alkyl quaternary ammonium ion, alkyl quaternary phosphonium ion, imidazole dibromide or sulfonium ion; Preferably, the anion of the ionic liquid includes Cl - , BF4 - , PF6 - , C3F7COO - , CF3SO3 - or (C4F9SO2)N - , preferably PF6 - or C3F7COO - .

5. The high-hardness elastomer composition according to any one of claims 1-4, characterized in that, The high-hardness elastomer composition further includes an additive; Preferably, the weight percentage of the additive is 0.095%-10.01%; Preferably, the additive includes any one or a combination of at least two of organic filler, inorganic filler, organic dye, inorganic dye, pigment, antioxidant or UV inhibitor; Preferably, the Shore hardness of the high-hardness elastomer composition is 55-84D; Preferably, the melt index of the high-hardness elastomer composition under the conditions of 230°C and 2.16 kg is 35-185 g / 10 min, and preferably 50-160 g / 10 min.

6. A preparation method of the high-hardness elastomer composition according to any one of claims 1-5, characterized in that, The preparation method includes the following steps: (1) Mix the ionic liquid and the high-hardness elastomer, and dry to obtain a mixture; (2) Mix, extrude and pelletize the mixture obtained in step (1) using a twin-screw extruder to obtain composition A; (3) Mix a part of composition A obtained in (2) with the high-hardness elastomer and optionally an additive, and then extrude using a single-screw extruder to obtain the high-hardness elastomer composition.

7. The preparation method according to claim 6, characterized in that, In step (1), based on the total mass of the ionic liquid and the high-hardness elastomer being 100%, the addition amount of the ionic liquid is 0.1-20%; Preferably, the addition amount of the part of composition A in step (3) is 1%-20% of composition A obtained in step (2), and preferably 1%-10%; Preferably, the addition amount of the high-hardness elastomer in step (3) is such that the weight percentage of the high-hardness elastomer in the high-hardness elastomer composition is 89.8%-99.9%, and the weight percentage of the ionic liquid is 0.001%-4%; Preferably, the addition amount of the additive in step (3) is such that the weight percentage of the additive in the high-hardness elastomer composition is 0.095%-10.01%.

8. The preparation method according to claim 6 or 7, characterized in that, The mixing in step (1) includes mixing using a low mixer; Preferably, the mixing time in step (1) is 5-15 min; Preferably, the drying temperature in step (1) is 80-100°C, and the drying time is 4-8 h.

9. The preparation method according to any one of claims 6-8, characterized in that, The twin-screw extruder in step (2) has a length-diameter ratio of 44-50, a processing temperature of 220-270°C, and a screw rotation speed of 90-400 rpm, and preferably 120-300 rpm; Preferably, the length-diameter ratio of the single-screw extruder in step (3) is 28 - 45, the processing temperature is 220 - 280 °C, and the screw rotation speed is 10 - 50 rpm.

10. Use of a high-hardness elastomer composition as described in any one of claims 1-5 in additive manufacturing, extrusion of films or pipelines.

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