Nylon elastomer foaming material as well as preparation method and application thereof

Abstract

The invention provides a nylon elastomer foaming material as well as a preparation method and application thereof. The foaming material comprises the following components in parts by weight: 100 parts of nylon elastomer; 0.1 to 10.0 parts of a tackifier; 0.1 to 4 parts of an antioxidant; 0.5-6 parts of a light stabilizer; the tackifier is selected from the group consisting of a maleic anhydride modified polymer, an isocyanate, an isocyanate dimer, an isocyanate trimer, or an NCO prepolymer. The method comprises the following steps: S1, melting the nylon elastomer to obtain a melt, continuously adding the tackifier, the antioxidant and the light stabilizer, mixing, and granulating to obtain to-be-foamed particles; s2, the to-be-foamed particles are subjected to foaming process treatment, and then the foaming material is obtained. The foaming material provided by the invention is used for insoles, shoe insoles, saddles, tires, helmets, cushions, interior ornaments and sports equipment. According to the nylon elastomer foaming material disclosed by the invention, the strength of the obtained foaming material can be remarkably improved under the condition that the dosage of the tackifier is relatively low, the influence on the foaming process is small, and the foaming material is relatively low in density and excellent in mechanical property in a balanced manner.

Description

Technical Field

[0001] The invention relates to the technical field of elastomer foaming materials, and in particular to a low-density and high-strength elastomer foaming material and a preparation method and application thereof. Background Art

[0002] There are many types of nylon elastomers (TPAE) according to the hard segment and soft segment components. At present, most of the nylon elastomers on the market are polyetheramide block copolymers (PEBA), a small amount of PEA (polyester block amide) and PEEA (polyether ester block amide). Compared with other thermoplastic elastomers (such as TPU, SBC, TPEE, etc.), nylon elastomers have the advantages of good comprehensive performance, good processability, transparency, and light weight. The molecular chain has excellent flexibility and good resilience; nylon elastomer materials have good low-temperature impact resistance and do not harden at low temperatures; low hysteresis and very good dynamic properties; chemical corrosion resistance, excellent anti-aging and sunlight exposure. Good flex and fatigue resistance, can reduce breakage, increase rebound and excellent "feel". Nylon elastomer materials are often used in the automotive industry, shoe materials, and as sports equipment.

[0003] Patent CN108250734B discloses a PEBA / TPU blended foaming material, in which PEBA and TPU are blended and granulated, a physical foaming agent is introduced into a high-pressure reactor, and the temperature and pressure are increased to reach a supercritical state, and then the pressure is quickly released to obtain microporous foamed beads. However, during the preparation process of the foaming material, the physical cross-linking points between the strong polar groups in the TPU molecules are easily reduced, resulting in severe shrinkage of the foamed beads and reduced resilience and tensile strength of the foaming material.

[0004] Patent CN111117215A discloses a thermoplastic elastomer foamed shoe material and its preparation method, which uses two or more nylon elastomers to blend and prepare the elastomer foam material through supercritical fluid foaming technology. Although the problem of uneven multiphase mixing is avoided, the mechanical properties are not really improved.

[0005] Patent CN108047702A discloses a thermoplastic elastomer and its foaming material, wherein PEBA is blended with one or more of POE and OBC, and then cross-linked to obtain a new thermoplastic elastomer material, and then the material is supercritically foamed to obtain the foaming material of the elastomer. However, the foaming material has two-phase or multi-phase blending, and there are problems such as insufficient mixing and phase separation at the micron scale, which leads to certain problems in the interface bonding between particles and shrinkage.

[0006] How to develop a nylon elastomer foam material that can improve the foaming effect, relatively low density and better mechanical properties is still one of the technical difficulties that urgently need to be broken through in this field. Summary of the invention

[0007] In order to solve the above-mentioned problems, the present invention provides a nylon elastomer foam material and its preparation and application, wherein a viscosity increasing effect is achieved by chemically reacting reactive groups such as anhydride, epoxy, NCO, etc. with the amide in the nylon elastomer, and at the same time, the polyether / ester segment or polyolefin segment in the viscosity increasing agent improves the performance of the soft segment, so that the foamed board has more excellent performance.

[0008] In order to achieve the purpose of the present invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a nylon elastomer foam material, wherein the foam material comprises the following components in parts by weight:

[0010]

[0011] Wherein, the tackifier is selected from polymers modified by maleic anhydride, isocyanates, isocyanate dimers, isocyanate trimers or NCO prepolymers.

[0012] In some embodiments, the polymer modified by maleic anhydride is selected from one or more of maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, maleic anhydride-modified polybutene or maleic anhydride-modified ethylene vinyl acetate; in some preferred embodiments, the number average molecular weight of the polymer modified by maleic anhydride is 10,000 to 50,000.

[0013] In some embodiments, the NCO prepolymer is selected from one or more of polyether, polyester, PCDL and PCL prepolymers;

[0014] In some specific embodiments, the nylon elastomer is a block copolymer of alternating hard segments and soft segments;

[0015] The hard segment of the block copolymer is selected from one or more polyamides such as poly-ε-decylamide (nylon 6), polybutylene adipamide (nylon 46), polyadipamide (nylon 66), polyhexamethylenediamine sebacamide (nylon 610), polyhexamethylenediamine dodecanoamide (nylon 612), polyundecanediamide (nylon 116), polyundecaneamide (nylon 11), polydodecanamide (nylon 12), polyhexamethylenediamine isophthalamide (nylon 6I), polyhexamethyleneterephthalamide (nylon 6T), polynonaneterephthalamide (nylon 9T), etc.;

[0016] The soft segment of the block copolymer is at least one of tetrahydrofuran polyether, propylene oxide polyether, polyethylene glycol, polycaprolactone, polyester diol formed by diol and dibasic acid, or polycarbonate.

[0017] In some specific embodiments, the antioxidant is selected from one or more of antioxidant 1010, antioxidant 1098, antioxidant 1076, and antioxidant 168.

[0018] In some specific embodiments, the light stabilizer is selected from one or more of UV-234, UV-292, UV-622 and UV-119S.

[0019] In a second aspect, the present invention provides a method for preparing the above-mentioned nylon elastomer foam material, which specifically comprises the following steps:

[0020] S1: Melting a nylon elastomer to obtain a melt, and then adding a tackifier, an antioxidant and a light stabilizer to the melt for mixing and granulation to obtain particles to be foamed;

[0021] S2: The particles to be foamed are subjected to a foaming process to obtain a nylon elastomer foaming material.

[0022] In some specific embodiments, in S1, melting is performed at 100-200° C. to obtain the melt;

[0023] Preferably, the granulation is carried out using a single screw or twin screw extruder at 160-220°C.

[0024] In a specific embodiment of the present invention, in S2, the particles to be foamed are foamed to obtain foamed particles; or,

[0025] The particles to be foamed are first made into a plate to be foamed or a profile to be foamed, and then foamed to obtain a foamed plate or a foamed profile.

[0026] In some specific embodiments, foaming is performed in S2 by a supercritical physical foaming process;

[0027] Preferably, the foamed particles are prepared in the following manner: placing the particles to be foamed in a supercritical foaming reactor, adding medium water into the supercritical foaming reactor at 50-100° C., introducing gas under stirring and pressurizing to 10-60 MPa, heating to 80-140° C., and then releasing the pressure and gas to obtain foamed particles;

[0028] The foamed plate or foamed profile is obtained by foaming in the following manner: the plate or profile to be foamed is placed in a supercritical foaming reactor, gas is introduced into the supercritical foaming reactor at 80-140° C. and pressurized to 10-60 MPa, saturated for 2-8 hours, heated to 100-160° C., and then the pressure is released to obtain the foamed plate or foamed profile.

[0029] In some specific embodiments, carbon dioxide and / or nitrogen are introduced into the supercritical foaming reactor; preferably, carbon dioxide is first introduced into the supercritical foaming reactor to pressurize the reactor to 2-30 MPa, and then nitrogen is introduced into the reactor to the required pressure.

[0030] In a third aspect, the present invention provides an application of a nylon elastomer foam material, wherein the nylon elastomer foam material is as described above or is prepared by the preparation method described above;

[0031] The nylon elastomer foam material is used for insoles, shoe midsoles, saddles, tires, helmets, cushions, interior decorations and sports equipment.

[0032] The technical solution provided by the present invention has the following beneficial effects:

[0033] The foaming material composition provided by the present invention can significantly improve the strength of the obtained foaming material at a lower tackifier dosage, and has little effect on the foaming process, so that the foaming material can balance the comprehensive properties such as relatively low density and good mechanical properties. DETAILED DESCRIPTION

[0034] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the invention belongs. The term "and / or" as may be used herein includes any and all combinations of one or more of the associated listed items.

[0036] The present invention provides a nylon elastomer foam material, comprising the following components in parts by weight:

[0037]

[0038]

[0039] Wherein, the tackifier is selected from polymers modified by maleic anhydride, isocyanates, isocyanate dimers, isocyanate trimers or NCO prepolymers.

[0040] In some embodiments, the polymer modified by maleic anhydride is selected from one or more of maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, maleic anhydride-modified polybutene or maleic anhydride-modified ethylene vinyl acetate; and / or,

[0041] The NCO prepolymer is selected from one or more of polyether, polyester, PCDL and PCL prepolymers. In some specific embodiments, the polyether prepolymer, polyester prepolymer, PCDL prepolymer and PCL prepolymer are obtained by reacting polyether polyol, polyester polyol, polycarbonate polyol and polycaprolactone polyol with polyisocyanate, respectively. The NCO content of the NCO prepolymer is preferably 20% to 30%, for example, 22%, 25%, 28%.

[0042] In some preferred embodiments, the number average molecular weight of the polymer modified by maleic anhydride is 10,000 to 50,000, for example, 20,000, 30,000, or 40,000.

[0043] In some embodiments, the nylon elastomer is a block copolymer of alternating hard segments and soft segments; the hard segment of the block copolymer is selected from one or more of poly-ε-decanoamide (nylon 6), polybutylene adipamide (nylon 46), polyadipamide (nylon 66), polyhexamethylenediamine sebacate (nylon 610), polyhexamethylenediamine dodecanoamide (nylon 612), polyundecapride (nylon 116), polyundecamide (nylon 11), polydodecanamide (nylon 12), polyhexamethylenediamine isophthalamide (nylon 6I), polyhexamethyleneterephthalamide (nylon 6T) and polynonaneterephthalamide (nylon 9T);

[0044] The soft segment of the block copolymer is at least one of tetrahydrofuran polyether, propylene oxide polyether, polyethylene glycol, polycaprolactone, polyester diol formed by diol and dibasic acid, or polycarbonate.

[0045] In some embodiments, the antioxidant is selected from one or more of antioxidant 1010, antioxidant 1098, antioxidant 1076, and antioxidant 168; the light stabilizer is selected from one or more of UV-234, UV-292, UV-622, and UV-119S.

[0046] The present invention also provides a method for preparing the above nylon elastomer foam material, comprising the following steps:

[0047] S1: Melting a nylon elastomer to obtain a melt, and then adding a tackifier, an antioxidant and a light stabilizer to the melt for mixing and granulation to obtain particles to be foamed;

[0048] S2: The particles to be foamed are subjected to a foaming process to obtain a nylon elastomer foaming material.

[0049] In the above S1, the melt is melted at 100-200°C to obtain the melt; in a preferred embodiment, granulation is carried out at 160-220°C using a single-screw or twin-screw extruder.

[0050] In S2, the particles to be foamed are subjected to foaming treatment to obtain foamed particles; or, the particles to be foamed are first made into a board to be foamed or a profile to be foamed, and then subjected to foaming treatment to obtain a foamed board or a foamed profile.

[0051] In some specific embodiments, foaming is performed in S2 by a supercritical physical foaming process;

[0052] Preferably, the foamed particles are prepared in the following manner: placing the particles to be foamed in a supercritical foaming reactor, adding medium water into the supercritical foaming reactor at 50-100° C., introducing gas under stirring and pressurizing to 10-60 MPa, heating to 80-140° C., and then releasing the pressure and gas to obtain foamed particles;

[0053] The foamed plate or foamed profile is obtained by foaming in the following manner: the plate or profile to be foamed is placed in a supercritical foaming reactor, gas is introduced into the supercritical foaming reactor at 80-140° C. and pressurized to 10-60 MPa, saturated for 2-8 hours, and then the temperature is raised to 100-160° C. and the pressure is released to obtain the foamed plate or foamed profile. In some specific embodiments, the shape difference of the foamed plate or foamed profile is generated according to the selection of the mold during the preparation process.

[0054] In some specific embodiments, carbon dioxide and / or nitrogen are introduced into the supercritical foaming reactor;

[0055] Preferably, carbon dioxide is first introduced into the supercritical foaming reactor to pressurize the reactor to 2-30 MPa, and then nitrogen is introduced into the reactor to a desired pressure.

[0056] The present invention also provides an application of a nylon elastomer foam material, wherein the nylon elastomer foam material is the above-mentioned material or is prepared by the above-mentioned preparation method;

[0057] The nylon elastomer foam material is used for insoles, shoe midsoles, saddles, tires, helmets, cushions, interior decorations and sports equipment.

[0058] The present invention is further described below by means of specific examples, but it should not be understood that the present invention is limited thereto.

[0059] Where specific experimental steps or conditions are not specified in the examples, the corresponding conventional experimental steps or conditions in the art can be used. The reagents used without specifying the manufacturer are all conventional reagents available in the art.

[0060] The raw materials used in the following embodiments of the present invention are shown in the following table:

[0061]

[0062] The test standards and methods of the following embodiments of the present invention are described as follows:

[0063] Shore-C hardness: GB / T10807-2006;

[0064] Density of expanded particles: ASTM D792;

[0065] Cell size: Determine the cell size by examining the cross-sectional morphology of the cells using an optical microscope or a scanning electron microscope;

[0066] 180° tear strength: ISO1798;

[0067] Rebound performance: DIN 53512;

[0068] Flatness: The flatness of foam products is evaluated by molding the foam beads into products using a non-textured flat mold, and then measuring the surface flatness of the products using a fixed-length ruler method. The maximum gap between the ruler reference plane and the product surface represents the road surface flatness, measured in mm. Each product is tested for 10 data and the average value is taken. The flatness of 10 products tested in each experiment is the average value.

[0069] Storage modulus: In DMA tensile mode, the temperature is increased from -100°C to 100°C, the heating rate is 3°C / min, the force is 10N, the amplitude is 30 microns, the frequency is 1Hz, and the value is taken at 25°C.

[0070] Example 1

[0071] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 0.05 kg of maleic anhydride-modified polyethylene with a number average molecular weight of 30,000, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 180°C, 185°C, 190°C, and 185°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0072] S2: preheat the mold to the required temperature of 180°C, then take out the mold, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 180°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0073] The sheet to be foamed is placed in a supercritical foaming kettle at 80°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0074] Example 2

[0075] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 0.5 kg of maleic anhydride-modified polyethylene with a number average molecular weight of 30,000, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 180°C, 185°C, 190°C, and 185°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0076] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 180°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 180°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0077] The sheet to be foamed is placed in a supercritical foaming kettle at 80°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0078] Example 3

[0079] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 2.5 kg of maleic anhydride-modified polyethylene with a number average molecular weight of 30,000, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 185°C, 190°C, 195°C, and 190°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0080] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 190°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 190°C for 20 minutes, hot press at 190°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0081] The sheet to be foamed is placed in a supercritical foaming kettle at 90°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0082] Example 4

[0083] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 5.0 kg of maleic anhydride-modified polyethylene with a number average molecular weight of 30,000, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 185°C, 190°C, 195°C, and 190°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0084] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 190°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 190°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0085] The sheet to be foamed is placed in a supercritical foaming kettle at 90°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0086] Example 5

[0087] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 2.5 kg of polyester prepolymer 3W3236 with an NCO content of 25% to 30%, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixed material was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 180°C, 185°C, 190°C, and 185°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0088] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 180°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 180°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0089] The sheet to be foamed is placed in a supercritical foaming kettle at 80°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0090] Example 6

[0091] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 2.5 kg of polyether prepolymer 3T3242 with an NCO content of 25% to 30%, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 180°C, 185°C, 190°C, and 185°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0092] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 180°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 180°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0093] The sheet to be foamed is placed in a supercritical foaming kettle at 80°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0094] Example 7

[0095] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 2.5 kg of maleic anhydride-modified polyethylene with a number average molecular weight of 50,000, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 188°C, 193°C, 198°C, and 193°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0096] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 180°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 180°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0097] The sheet to be foamed is placed in a supercritical foaming kettle at 95°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 120°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0098] Example 8

[0099] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 0.5 kg of maleic anhydride-modified polyethylene with a number average molecular weight of 30,000, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 180°C, 185°C, 190°C, and 185°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0100] S2: Place the particles to be foamed into a supercritical foaming kettle at 80°C, quickly add water 5 times the mass of the particles to be foamed, introduce carbon dioxide to increase the pressure in the kettle to 4MPa, then introduce nitrogen to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, raise the temperature to 115°C, and quickly release the pressure and gas to obtain a nylon elastomer foaming material.

[0101] Example 9

[0102] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 2.5 kg of HDI, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 180°C, 185°C, 190°C, and 185°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0103] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 180°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 180°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0104] The sheet to be foamed is placed in a supercritical foaming kettle at 80°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0105] Example 10

[0106] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 2.5 kg of HDI dimer, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 180°C, 185°C, 190°C, and 185°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0107] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 180°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 180°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0108] The sheet to be foamed is placed in a supercritical foaming kettle at 80°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0109] Embodiment 11

[0110] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 2.5 kg of HDI trimer, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 190°C, 195°C, 200°C, and 195°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0111] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 195°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 195°C for 20 minutes, hot press at 195°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0112] The sheet to be foamed is placed in a supercritical foaming kettle at 90°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 125°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0113] Application Example 1

[0114] The nylon elastomer foam material obtained in the above Example 1 is subjected to secondary molding at 110-140° C. to prepare a shoe midsole or insole.

[0115] Application Example 2

[0116] The nylon elastomer foam material obtained in the above Example 4 is subjected to secondary molding at 115-150° C. to prepare a shoe midsole or insole.

[0117] Application Example 3

[0118] The nylon elastomer foam material obtained in the above Example 6 is subjected to secondary molding at 110-140° C. to prepare a shoe midsole or insole.

[0119] Application Example 4

[0120] The nylon elastomer foam material obtained in the above Example 11 is subjected to secondary molding at 120-160° C. to prepare a shoe midsole or insole.

[0121] Comparative Example 1

[0122] The mold was preheated in advance, and after reaching the required temperature of 180°C, the mold was taken out, and the nylon elastomer 4011 sample to be foamed was placed in a 4mm mold, and molded according to the steps of preheating at 180°C for 20 minutes, hot pressing at 180°C for 10 minutes, and cold pressing at room temperature for 10 minutes to obtain a sheet to be foamed;

[0123] The sheet to be foamed is placed in a supercritical foaming reactor at 80°C, carbon dioxide is introduced to increase the pressure in the reactor to 4MPa, and nitrogen is continued to be introduced to increase the pressure in the reactor to 20MPa. Saturation is carried out for 2h, and then the temperature is raised to 115°C, and then the pressure is quickly released to obtain a nylon elastomer foaming material.

[0124] Comparative Example 2

[0125] S1: 50 kg of nylon elastomer 4011 was dried and put into an internal mixer, the speed was set to 60 r / min, and melted at 180°C to obtain a melt; when the torque was stable, 2.5 kg of pyromellitic anhydride, 1 kg of antioxidant 1010, and 1 kg of light stabilizer UV-236 were added according to the formula and continued to mix for 10 minutes; then the mixture was put into a single-screw extruder, and the temperatures of the four zones from the feed section to the die head were 180°C, 185°C, 190°C, and 185°C respectively, and the particles to be foamed were obtained after extrusion granulation;

[0126] S2: preheat the mold in advance, take out the mold after reaching the required temperature of 180°C, put the particles to be foamed obtained in S1 into a 4 mm mold, preheat at 180°C for 20 minutes, hot press at 180°C for 10 minutes, and cold press at room temperature for 10 minutes to obtain a sheet to be foamed;

[0127] The sheet to be foamed is placed in a supercritical foaming kettle at 80°C, carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and then nitrogen is introduced to continue to increase the pressure in the kettle to 20MPa. After saturation for 2h, the temperature is raised to 115°C, and the pressure is quickly released to obtain a nylon elastomer foaming material.

[0128] Comparative Example 3

[0129] The nylon elastomer 4011 to be foamed is placed in a supercritical foaming kettle at 80°C, and water 5 times the mass of the particles to be foamed is quickly added. Carbon dioxide is introduced to increase the pressure in the kettle to 4MPa, and nitrogen is continued to be introduced to increase the pressure in the kettle to 20MPa. Saturation is carried out for 2h, and then the temperature is raised to 115°C, and then the pressure is quickly released and the gas is discharged to obtain the nylon elastomer foaming material.

[0130] The foaming material obtained in the above embodiment was tested for foaming performance, wherein the foaming materials (foaming particles) obtained in Example 8 and Comparative Example 3 were compression molded into 300mm×200mm×20mm foamed plates, and then the above foaming performance test was performed. The test results are shown in Table 1 below:

[0131] Table 1

[0132]

[0133]

[0134] From the test results in Table 1 above, it can be seen that compared with the comparative example, the nylon elastomer foam material provided by the present invention can obtain a low density (0.08-0.1 g / cm 3 ), high rebound (79-85%), while taking into account good mechanical properties (tear strength 2.3-4.0KN / m) and other comprehensive properties.

Claims

1. A nylon elastomer foam material, characterized in that: The foaming material comprises the following components in parts by weight: Wherein, the tackifier is selected from polymers modified by maleic anhydride, isocyanates, isocyanate dimers, isocyanate trimers or NCO prepolymers.

2. The nylon elastomer foam material according to claim 1, characterized in that: The polymer modified by maleic anhydride is selected from one or more of maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, maleic anhydride-modified polybutene or maleic anhydride-modified ethylene vinyl acetate; and / or, The NCO prepolymer is selected from one or more of polyether type, polyester type, PCDL type and PCL type prepolymer; Preferably, the number average molecular weight of the polymer modified by maleic anhydride is 10,000 to 50,000.

3. The nylon elastomer foam material according to claim 2, characterized in that: The nylon elastomer is a block copolymer of alternating hard segments and soft segments; The hard segment of the block copolymer is selected from one or more of poly-ε-decylamide, polybutylene adipamide, polyadipamide, polyhexamethylenediamine sebacate, polyhexamethylenedodecanoyldiamine, polyundecaneadipamide, polyundecaneamide, polydodecamide, polyhexamethyleneisophthalamide, polyhexamethyleneterephthalamide and polynonamethyleneterephthalamide; The soft segment of the block copolymer is at least one of tetrahydrofuran polyether, propylene oxide polyether, polyethylene glycol, polycaprolactone, polyester diol formed by diol and dibasic acid, or polycarbonate.

4. The nylon elastomer foam material according to any one of claims 1 to 3, characterized in that: The antioxidant is selected from one or more of antioxidant 1010, antioxidant 1098, antioxidant 1076, and antioxidant 168; The light stabilizer is selected from one or more of UV-234, UV-292, UV-622 and UV-119S.

5. A method for preparing the nylon elastomer foam material according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: Melting a nylon elastomer to obtain a melt, and then adding a tackifier, an antioxidant and a light stabilizer to the melt for mixing and granulation to obtain particles to be foamed; S2: The particles to be foamed are subjected to a foaming process to obtain a nylon elastomer foaming material.

6. The preparation method according to claim 5, characterized in that: In S1, melting is performed at 100 to 200° C. to obtain the melt; Preferably, the granulation is carried out using a single screw or twin screw extruder at 160-220°C.

7. The preparation method according to claim 6, characterized in that: In S2, the particles to be foamed are foamed to obtain foamed particles; or, The particles to be foamed are first made into a plate to be foamed or a profile to be foamed, and then foamed to obtain a foamed plate or a foamed profile.

8. The preparation method according to claim 7, characterized in that: In S2, foaming is performed by a supercritical physical foaming process; Preferably, the foamed particles are prepared in the following manner: placing the particles to be foamed in a supercritical foaming reactor, adding medium water into the supercritical foaming reactor at 50-100° C., introducing gas under stirring and pressurizing to 10-60 MPa, heating to 80-140° C., and then releasing the pressure and gas to obtain foamed particles; The foamed plate or foamed profile is obtained by foaming in the following manner: the plate or profile to be foamed is placed in a supercritical foaming reactor, gas is introduced into the supercritical foaming reactor at 80-140° C. and pressurized to 10-60 MPa, saturated for 2-8 hours, heated to 100-160° C., and then the pressure is released to obtain the foamed plate or foamed profile.

9. The preparation method according to claim 8, characterized in that: Introducing carbon dioxide and / or nitrogen into the supercritical foaming reactor; Preferably, carbon dioxide is first introduced into the supercritical foaming reactor to pressurize the reactor to 2-30 MPa, and then nitrogen is introduced into the reactor to a desired pressure.

10. An application of a nylon elastomer foam material, characterized in that: The nylon elastomer foam material is made according to any one of claims 1 to 4 or by the preparation method according to any one of claims 5 to 9; The nylon elastomer foam material is used for insoles, shoe midsoles, saddles, tires, helmets, cushions, interior decorations and sports equipment.

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