A nylon elastomer foamed material and its preparation method and application

Abstract

The present application provides a kind of nylon elastomer foamed material and its preparation method and application, foamed material includes the following weight parts components: nylon elastomer 100 parts;Tackifier 0.1-10.0 parts;Antioxidant 0.1-4 parts;Light stabilizer 0.5-6 parts;Tackifier is selected from maleic anhydride modified polymer, isocyanate, isocyanate dimer, isocyanate trimer or NCO prepolymer.Method: S1: melt nylon elastomer to obtain melt, continue to add tackifier, antioxidant and light stabilizer to mix, granulation is obtained to be foamed granule;S2: after being foamed granule is handled by foaming process, foamed material is obtained.The foamed material of the present application is used for insole, shoe midsole, saddle, tire, helmet, cushion, interior decoration and sports equipment.The foamed material of the present application can significantly improve the strength of the obtained foamed material at a lower amount of tackifier, has little effect on the foaming process, so that the foamed material balances the relatively low density and excellent mechanical properties.

Description

Technical Field

[0001] This invention relates to the technical field of elastomer foam materials, specifically to a low-density, high-strength elastomer foam material and its preparation and application. Background Technology

[0002] Depending on the composition of the hard and soft segments, there are many types of nylon elastomers (TPAE). Currently, the vast majority of nylon elastomers on the market are polyether amide block copolymers (PEBA), with smaller amounts being PEA (polyester block amide) and PEEA (polyether ester block amide). Compared with other thermoplastic elastomers (such as TPU, SBC, TPEE, etc.), nylon elastomers have advantages such as good overall performance, good processability, transparency, and light weight. The molecular chains have excellent flexibility and good resilience; nylon elastomer materials have good low-temperature impact resistance and do not harden at low temperatures; they have low hysteresis and very good dynamic properties; they are resistant to chemical corrosion and have excellent anti-aging and sun exposure resistance. They have good flexural and fatigue resistance, reducing breakage, increasing resilience, and providing excellent "feel." Nylon elastomer materials are commonly used in the automotive industry, footwear materials, and sporting goods.

[0003] Patent CN108250734B discloses a PEBA / TPU blended foam material. After blending PEBA and TPU, the mixture is granulated and then a physical foaming agent is introduced into a high-pressure reactor. The reactor is heated and pressurized to reach a supercritical state, and then the pressure is rapidly released to obtain microporous foam beads. However, during the preparation of this foam material, the physical cross-linking points between the strongly polar groups in the TPU molecules are easily reduced, resulting in severe shrinkage of the foam beads and a decrease in the resilience and tensile strength of the foam material.

[0004] Patent CN111117215A discloses a thermoplastic elastomer foamed shoe material and its preparation method. It uses a blend of two or more nylon elastomers and prepares the foamed material using supercritical fluid foaming technology. While this avoids the problem of uneven multiphase mixing, the mechanical properties are not truly improved.

[0005] Patent CN108047702A discloses a thermoplastic elastomer and its foaming material. It is obtained by blending PEBA with one or more of POE and OBC, and then cross-linking the mixture to obtain a new thermoplastic elastomer material. This material is then subjected to supercritical foaming to obtain the foamed material of this elastomer. However, this foamed material has two or more phases, which may result in insufficient mixing, micron-scale phase separation, and certain problems with interparticle bonding and shrinkage.

[0006] Developing a material that can improve the foaming properties of nylon elastomers while maintaining good foaming performance, relatively low density, and good mechanical properties remains one of the key technical challenges that urgently needs to be overcome in this field. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a nylon elastomer foam material, its preparation, and its application. The material achieves a tackifying effect through a chemical reaction between reactive groups such as acid anhydrides, epoxy, and NCO and amides in the nylon elastomer. Simultaneously, the polyether / ester or polyolefin segments in the tackifier improve the performance of the soft segments, resulting in superior performance of the foamed board.

[0008] To achieve the objectives of this invention, the following technical solution is adopted:

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

[0010]

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

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

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

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

[0015] The hard segments of the block copolymer are selected from one or more polyamides, including poly(ε-decanoamide) (Nylon 6), poly(butylene adipamide) (Nylon 46), poly(diamide adipamide) (Nylon 66), poly(hexamethylene sebacate) (Nylon 610), poly(hexamethylene dodecanoate) (Nylon 612), poly(undecanoate) (Nylon 116), poly(undecanamide) (Nylon 11), poly(dodecanoamide) (Nylon 12), poly(hexamethylene isophthalamide) (Nylon 6I), poly(hexamethylene terephthalamide) (Nylon 6T), and poly(nonadiamine terephthalamide) (Nylon 9T).

[0016] The soft segments of the block copolymer are at least one of tetrahydrofuran polyether, propylene oxide polyether, polyethylene glycol, polycaprolactone, and polyester diol or polycarbonate formed from diol and diacid.

[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, specifically comprising the following steps:

[0020] S1: Melt nylon elastomer to obtain melt, then add tackifier, antioxidant and light stabilizer to it, mix and granulate to obtain foaming granules;

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

[0022] In some specific embodiments, in S1, the melt is obtained by melting at 100-200°C;

[0023] Preferably, granulation is performed 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 obtained by foaming treatment; or,

[0025] First, the granules to be foamed are made into foamed boards or foamed profiles, and then foamed boards or foamed profiles are obtained through foaming treatment.

[0026] In some specific implementations, foaming in S2 is carried out using a supercritical physical foaming process;

[0027] Preferably, the foamed particles are prepared in the following manner: the particles to be foamed are placed in a supercritical foaming reactor, medium water is added to the supercritical foaming reactor at 50-100°C, and gas is introduced under stirring and pressurized to 10-60 MPa. After heating to 80-140°C, the pressure is released and the gas is released to obtain foamed particles.

[0028] The foamed board or foamed profile is obtained by foaming in the following manner: the board or profile to be foamed is placed in a supercritical foaming kettle, and gas is introduced into the supercritical foaming kettle at 80-140°C and pressurized to 10-60 MPa. After saturation for 2-8 hours, the temperature is raised to 100-160°C and the pressure is released to obtain the foamed board 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 prepared by the above preparation method;

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

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

[0033] The foaming material composition provided by the present invention can significantly improve the strength of the resulting foamed material with a low amount of tackifier, while having little impact on the foaming process, and can make the foamed material balance relatively low density and good mechanical properties. Detailed Implementation

[0034] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

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

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

[0037]

[0038]

[0039] The tackifier is selected from maleic anhydride-modified polymers, 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-type, polyester-type, PCDL-type, and PCL-type prepolymers. In some specific embodiments, the polyether-type prepolymer, polyester-type prepolymer, PCDL-type prepolymer, and PCL-type prepolymer are obtained by reacting polyether polyol, polyester polyol, polycarbonate polyol, and polycaprolactone polyol with polyisocyanate, respectively. The NCO content in the NCO prepolymer is preferably 20% to 30%, for example, 22%, 25%, and 28%.

[0042] In some preferred embodiments, the number-average molecular weight of the maleic anhydride-modified polymer 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 with alternating hard and soft segments; the hard segments of the block copolymer are selected from one or more of poly(ε-decanoamide) (nylon 6), poly(butylene adipamide) (nylon 46), poly(diamide adipamide) (nylon 66), poly(hexamethylene decanediamide) (nylon 610), poly(hexamethylene dodecanoyl) (nylon 612), poly(undecanoyl) (nylon 116), poly(undecanoamide) (nylon 11), poly(dodecanoamide) (nylon 12), poly(hexamethylene isophthalamide) (nylon 6I), poly(hexamethylene terephthalamide) (nylon 6T), and poly(nonadiamine terephthalamide) (nylon 9T);

[0044] The soft segments of the block copolymer are at least one of tetrahydrofuran polyether, propylene oxide polyether, polyethylene glycol, polycaprolactone, and polyester diol or polycarbonate formed from diol and diacid.

[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-mentioned nylon elastomer foam material, comprising the following steps:

[0047] S1: Melt nylon elastomer to obtain melt, then add tackifier, antioxidant and light stabilizer to it, mix and granulate to obtain foaming granules;

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

[0049] In S1 above, the melt is obtained by melting at 100-200°C; in a preferred embodiment, granulation is performed at 160-220°C using a single-screw or twin-screw extruder.

[0050] In S2, the particles to be foamed are obtained by foaming treatment; or, the particles to be foamed are first made into foamed boards or foamed profiles, and then foamed to obtain foamed boards or foamed profiles.

[0051] In some specific implementations, foaming in S2 is carried out using a supercritical physical foaming process;

[0052] Preferably, the foamed particles are prepared in the following manner: the particles to be foamed are placed in a supercritical foaming reactor, medium water is added to the supercritical foaming reactor at 50-100°C, and gas is introduced under stirring and pressurized to 10-60 MPa. After heating to 80-140°C, the pressure is released and the gas is released to obtain foamed particles.

[0053] The foamed board or foamed profile is prepared by foaming as follows: The board or profile to be foamed is placed in a supercritical foaming reactor. Gas is introduced into the reactor at 80–140°C and pressurized to 10–60 MPa. After saturation for 2–8 hours, the temperature is raised to 100–160°C, and the pressure is released to obtain the foamed board or foamed profile. In some specific embodiments, the shape of the foamed board or foamed profile varies depending on the mold selected 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 the required pressure.

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

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

[0058] The present invention will be further illustrated below with specific examples, but it should not be construed as the present invention being limited to these examples.

[0059] Where specific experimental steps or conditions are not specified in the examples, they can be performed according to the corresponding conventional experimental steps or conditions in this technical field. Reagents whose manufacturers are not specified are all conventional reagents already available in this field.

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

[0061]

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

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

[0064] Density of foamed particles: ASTM D792;

[0065] Cell size: The cross-sectional morphology of the cells is examined using an optical microscope or scanning electron microscope to determine the cell size;

[0066] 180° tear strength: ISO1798;

[0067] Rebound performance: DIN 53512;

[0068] Smoothness: The smoothness assessment of foam products is carried out by molding foam beads into products using a textureless smooth mold, and then measuring the surface smoothness of the products using a fixed-length ruler method. The maximum gap between the ruler reference surface and the product surface is used to represent the road surface smoothness, measured in mm. Ten data points are tested for each product and the average value is taken. The smoothness of the 10 products tested in each experiment is taken as the average value.

[0069] Energy storage modulus: In DMA stretching mode, the temperature is increased from -100℃ to 100℃ at a rate of 3℃ / min, with a force of 10N, an amplitude of 30 micrometers, and a frequency of 1Hz. The value is taken at 25℃.

[0070] Example 1

[0071] S1: After drying 50 kg of nylon elastomer 4011, put it into a mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 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 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 180℃, 185℃, 190℃, and 185℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0072] S2: After preheating the mold to the required temperature of 180°C, remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Then, press the mold according to the following steps: 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 the foaming board.

[0073] The foamed material is placed in a supercritical foaming reactor at 80°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0074] Example 2

[0075] S1: After drying 50 kg of nylon elastomer 4011, put it into an internal mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 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 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 180℃, 185℃, 190℃, and 185℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0076] S2: Preheat the mold to the required temperature of 180℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the mold according to the following steps: preheat at 180℃ for 20 minutes, hot press at 180℃ for 10 minutes, and cold press at room temperature for 10 minutes to obtain the foaming board.

[0077] The foamed material is placed in a supercritical foaming reactor at 80°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0078] Example 3

[0079] S1: After drying 50 kg of nylon elastomer 4011, put it into a mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 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 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 185℃, 190℃, 195℃, and 190℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0080] S2: Preheat the mold to the required temperature of 190℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the mold according to the following steps: preheating at 190℃ for 20 minutes, hot pressing at 190℃ for 10 minutes, and cold pressing at room temperature for 10 minutes to obtain the foaming board.

[0081] The foamed material is placed in a supercritical foaming reactor at 90°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0082] Example 4

[0083] S1: After drying 50 kg of nylon elastomer 4011, put it into a mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 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 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 185℃, 190℃, 195℃, and 190℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0084] S2: Preheat the mold to the required temperature of 190℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the foaming material by preheating at 190℃ for 20 minutes, hot pressing at 180℃ for 10 minutes, and cold pressing at room temperature for 10 minutes.

[0085] The foamed material is placed in a supercritical foaming reactor at 90°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0086] Example 5

[0087] S1: After drying 50 kg of nylon elastomer 4011, put it into a mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 2.5 kg of polyester prepolymer 3W3236 with NCO content of 25% to 30%, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 180℃, 185℃, 190℃, and 185℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0088] S2: Preheat the mold to the required temperature of 180℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the mold according to the following steps: preheat at 180℃ for 20 minutes, hot press at 180℃ for 10 minutes, and cold press at room temperature for 10 minutes to obtain the foaming board.

[0089] The foamed material is placed in a supercritical foaming reactor at 80°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0090] Example 6

[0091] S1: After drying 50 kg of nylon elastomer 4011, put it into a mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 2.5 kg of polyether prepolymer 3T3242 with NCO content of 25% to 30%, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 180℃, 185℃, 190℃, and 185℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0092] S2: Preheat the mold to the required temperature of 180℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the mold according to the following steps: preheat at 180℃ for 20 minutes, hot press at 180℃ for 10 minutes, and cold press at room temperature for 10 minutes to obtain the foaming board.

[0093] The foamed material is placed in a supercritical foaming reactor at 80°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0094] Example 7

[0095] S1: After drying 50 kg of nylon elastomer 4011, put it into an internal mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 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 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 188℃, 193℃, 198℃, and 193℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0096] S2: Preheat the mold to the required temperature of 180℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the mold according to the following steps: preheat at 180℃ for 20 minutes, hot press at 180℃ for 10 minutes, and cold press at room temperature for 10 minutes to obtain the foaming board.

[0097] The foamed material is placed in a supercritical foaming reactor at 95°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 120°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0098] Example 8

[0099] S1: After drying 50 kg of nylon elastomer 4011, put it into an internal mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 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 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 180℃, 185℃, 190℃, and 185℃ respectively. After extrusion granulation, the foaming granules are obtained.

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

[0101] Example 9

[0102] S1: After drying 50 kg of nylon elastomer 4011, put it into an internal mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 2.5 kg of HDI, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 180℃, 185℃, 190℃, and 185℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0103] S2: Preheat the mold to the required temperature of 180℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the mold according to the following steps: preheat at 180℃ for 20 minutes, hot press at 180℃ for 10 minutes, and cold press at room temperature for 10 minutes to obtain the foaming board.

[0104] The foamed material is placed in a supercritical foaming reactor at 80°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0105] Example 10

[0106] S1: After drying 50 kg of nylon elastomer 4011, put it into an internal mixer and set the speed to 60 r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 2.5 kg of HDI dimer, 1.0 kg of antioxidant 1010, and 1.0 kg of light stabilizer UV-236 according to the formula and continue mixing for 10 min. Then put the mixture into a single screw extruder. The temperatures of the four zones from the feed section to the die head are 180℃, 185℃, 190℃, and 185℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0107] S2: Preheat the mold to the required temperature of 180℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the mold according to the following steps: preheat at 180℃ for 20 minutes, hot press at 180℃ for 10 minutes, and cold press at room temperature for 10 minutes to obtain the foaming board.

[0108] The foamed material is placed in a supercritical foaming reactor at 80°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0109] Example 11

[0110] S1: After drying 50kg of nylon elastomer 4011, put it into an internal mixer and set the speed to 60r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 2.5kg of HDI trimer, 1.0kg of antioxidant 1010, and 1.0kg of light stabilizer UV-236 according to the formula and continue mixing for 10min. Then put the mixture into a single screw extruder. The temperatures of the four zones from the feed section to the die head are 190℃, 195℃, 200℃, and 195℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0111] S2: Preheat the mold to the required temperature of 195℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the foaming material by preheating at 195℃ for 20 minutes, hot pressing at 195℃ for 10 minutes, and cold pressing at room temperature for 10 minutes.

[0112] The foamed board is placed in a supercritical foaming reactor at 90°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 125°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0113] Application Example 1

[0114] The nylon elastomer foam material obtained in Example 1 above is used to prepare shoe midsoles or insoles by secondary molding at 110-140°C.

[0115] Application Example 2

[0116] The nylon elastomer foam material obtained in Example 4 above was used to prepare shoe midsoles or insoles by secondary molding at 115-150°C.

[0117] Application Example 3

[0118] The nylon elastomer foam material obtained in Example 6 above was used to prepare shoe midsoles or insoles by secondary molding at 110-140°C.

[0119] Application Example 4

[0120] The nylon elastomer foam material obtained in Example 11 above is used to prepare shoe midsoles or insoles by secondary molding at 120-160°C.

[0121] Comparative Example 1

[0122] Preheat the mold to the required temperature of 180℃, then remove the mold and place the nylon elastomer 4011 sample to be foamed into the 4mm mold. Perform molding according to the following steps: preheating at 180℃ for 20 minutes, hot pressing at 180℃ for 10 minutes, and cold pressing at room temperature for 10 minutes to obtain the foamed board.

[0123] The foamed board is placed in a supercritical foaming reactor at 80°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Nitrogen gas is then introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and then the pressure is quickly released to obtain nylon elastomer foam material.

[0124] Comparative Example 2

[0125] S1: After drying 50kg of nylon elastomer 4011, put it into a mixer and set the speed to 60r / min. Melt it at 180℃ to obtain a melt. After the torque stabilizes, add 2.5kg of pyromellitic anhydride, 1kg of antioxidant 1010, and 1kg of light stabilizer UV-236 according to the formula and continue mixing for 10min. Then put the mixture into a single screw extruder. The temperature of the four zones from the feed section to the die head is 180℃, 185℃, 190℃, and 185℃ respectively. After extrusion granulation, the foaming granules are obtained.

[0126] S2: Preheat the mold to the required temperature of 180℃, then remove the mold and put the foaming particles obtained in S1 into the 4mm mold. Mold the mold according to the following steps: preheat at 180℃ for 20 minutes, hot press at 180℃ for 10 minutes, and cold press at room temperature for 10 minutes to obtain the foaming board.

[0127] The foamed material is placed in a supercritical foaming reactor at 80°C. Carbon dioxide is introduced to increase the pressure inside the reactor to 4MPa. Then, nitrogen is introduced to further increase the pressure inside the reactor to 20MPa. After saturation for 2 hours, the temperature is raised to 115°C, and the pressure is quickly released to obtain nylon elastomer foam material.

[0128] Comparative Example 3

[0129] The nylon elastomer 4011 to be foamed was placed in a supercritical foaming reactor at 80°C. Water with a mass of 5 times that of the particles to be foamed was quickly added. Carbon dioxide was introduced to increase the pressure inside the reactor to 4 MPa. Nitrogen gas was then introduced to further increase the pressure inside the reactor to 20 MPa. After saturation for 2 hours, the temperature was raised to 115°C. Then the pressure was quickly released to obtain the nylon elastomer foam material.

[0130] The foamed materials obtained in the above embodiments were subjected to foaming performance testing. Among them, the foamed materials (foamed particles) obtained in Example 8 and Comparative Example 3 were molded into 300mm×200mm×20mm foamed boards before the above foaming performance testing was performed. The test results are shown in Table 1 below:

[0131] Table 1

[0132]

[0133]

[0134] As can be seen from the test results in Table 1 above, compared with the comparative example, the nylon elastomer foam material provided by the present invention can achieve a low density (0.08~0.1 g / cm³). 3 It has high resilience (79-85%), while also 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: 100 parts of nylon elastomer; Tackifier 0.1~10.0 parts; Antioxidant 0.1-4 parts; Light stabilizer 0.5-6 parts; The tackifier is selected from maleic anhydride-modified polymers, isocyanate dimers, isocyanate trimers, or NCO prepolymers; wherein the number-average molecular weight of the maleic anhydride-modified polymer is 10,000 to 50,000. The nylon elastomer is a block copolymer with alternating hard and soft segments; The hard segments of the block copolymer are selected from polyundecanoamide and / or polydodecanoamide; The soft segments of the block copolymer are at least one of tetrahydrofuran polyether, propylene oxide polyether, polyethylene glycol, polycaprolactone, and polyester diol or polycarbonate formed from diol and diacid.

2. The nylon elastomer foam material according to claim 1, characterized in that, The maleic anhydride-modified polymer 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 polyether-type, polyester-type, and PCDL-type prepolymers.

3. The nylon elastomer foam material according to claim 1, 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.

4. A method for preparing the nylon elastomer foam material according to any one of claims 1 to 3, characterized in that, Includes the following steps: S1: Melt nylon elastomer to obtain melt, then add tackifier, antioxidant and light stabilizer to it, mix and granulate to obtain foaming granules; S2: The particles to be foamed are processed by a foaming process to obtain nylon elastomer foam material.

5. The preparation method according to claim 4, characterized in that, In S1, the melt is obtained by melting at 100~200℃.

6. The preparation method according to claim 5, characterized in that, Granulation is performed using a single-screw or twin-screw extruder at 160~220℃.

7. The preparation method according to claim 5, characterized in that, In S2, the particles to be foamed are obtained by foaming treatment; or, First, the granules to be foamed are made into foamed boards or foamed profiles, and then foamed boards or foamed profiles are obtained through foaming treatment.

8. The preparation method according to claim 7, characterized in that, S2 is foamed using a supercritical physical foaming process.

9. The preparation method according to claim 8, characterized in that, The foamed board or foamed profile is obtained by foaming in the following manner: the board or profile to be foamed is placed in a supercritical foaming kettle, and gas is introduced into the supercritical foaming kettle at 80~140℃ and pressurized to 10~60 MPa. After saturation for 2~8 h, the temperature is raised to 100~160℃ and the pressure is released to obtain the foamed board or foamed profile.

10. The preparation method according to claim 8, characterized in that, Carbon dioxide and / or nitrogen are introduced into the supercritical foaming reactor.

11. The preparation method according to claim 10, characterized in that, First, carbon dioxide is introduced into the supercritical foaming reactor to pressurize it to 2-30 MPa, and then nitrogen is introduced into the reactor to the required pressure.

12. An application of a nylon elastomer foam material, characterized in that, The nylon elastomer foam material is prepared according to any one of claims 1 to 3 or by any one of the preparation methods described in claims 4 to 11; The nylon elastomer foam material is used in insoles, shoe midsoles, saddles, tires, helmets, cushioning pads, interior decorations, and sports equipment.

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