Anti-yellowing glue plastic track and preparation method thereof

Abstract

The invention relates to the technical field of plastic runways, in particular to an anti-yellowing glue plastic runway and a preparation method thereof. The runway is prepared by compounding modified EPDM particles and polyurethane glue according to the weight ratio of 5: (0.8-1.2). A two-step interface modification technology is innovatively adopted, wherein trimethoxysilane active groups are grafted on the surface of EPDM through a silane coupling agent KH-570, and then a three-dimensional cross-linked network is constructed through KH-550, polyethyleneimine and polyether amine. According to the glue system, polytetrahydrofuran ether glycol and isophorone diisocyanate are synthesized into a prepolymer, and a nano calcium carbonate / hindered amine light stabilizer / aluminum acetylacetonate synergistic system is compounded. According to the technology, the particle-matrix interface bonding force is remarkably enhanced through gradient chemical bonding, and the obtained runway has high durability and is particularly suitable for construction of sports fields in high-latitude and strong-ultraviolet regions.

Description

Technical Field

[0001] The invention relates to the technical field of plastic runways, and in particular to a yellowing-resistant glue plastic runway and a preparation method thereof. Background Art

[0002] Ethylene propylene diene monomer (EPDM) has become the main raw material for plastic track particles due to its excellent weather resistance, elasticity and cost advantages. However, the saturated ethylene-propylene structure in the EPDM molecular chain makes it highly non-polar and low surface energy, resulting in poor interfacial compatibility with the polar polyurethane glue matrix. In traditional processes, EPDM particles and glue are only combined by physical adsorption. This weak interaction is prone to failure under environmental stresses such as wet-heat cycles and freeze-thaw cycles, causing interface debonding, stratification and even blistering. Especially under dynamic loads, the relative slip between the particles and the matrix will form microcracks and gradually expand, resulting in insufficient tensile strength (usually less than 1.5MPa) and high compression set (generally more than 35%). In addition, long-term ultraviolet irradiation will induce photo-oxidative breakage of the urethane bonds in the glue molecular chain, and conventional antioxidants are prone to migrate to the surface and be washed away by rainwater due to the lack of chemical bonding with the matrix, causing the material to yellow (ΔE value > 6) and accelerated decline in mechanical properties.

[0003] Existing modification technologies attempt to improve the interfacial properties of EPDM through surface treatment, but there are still significant limitations: although single silane coupling agent modification can enhance the bonding strength through the reaction of silanol and glue, the rigid silane layer formed is prone to brittle cracking under repeated deformation and cannot effectively dissipate impact energy; although the introduction of flexible segments can enhance toughness, excessive flexible components will lead to a decrease in the rigidity of the material, making it difficult to meet the compressive strength requirements of the runway; when nanofillers are reinforced, due to the lack of active sites on the EPDM surface, the fillers are prone to agglomeration to form stress concentration points, which in turn aggravate wear. Therefore, how to simultaneously achieve high strength, anti-yellowing and long-term durability remains a core challenge in the field of plastic track materials. Summary of the invention

[0004] In view of this, the purpose of the present invention is to propose a yellowing-resistant glue plastic track and a preparation method thereof, so as to solve the problem that the existing plastic track materials have poor mechanical properties and durability due to insufficient interface bonding between EPDM particles and glue matrix.

[0005] Based on the above purpose, the present invention provides a yellowing-resistant glue plastic track, which is prepared by modified EPDM particles and glue in a weight ratio of 5:0.8-1.2.

[0006] Furthermore, the preparation method of the modified EPDM particles is as follows:

[0007] (1) EPDM particles are immersed in a cyclohexanone solution containing a silane coupling agent KH-570 and diisopropylbenzene peroxide at 35-45° C. for 1.5-2.5 hours, then heated to 115-125° C., stirred for reaction for 2-4 hours, centrifuged, washed, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface;

[0008] (2) Add EPDM particles with trimethoxysilane grafted on the surface into deionized water and ethanol, then add silane coupling agent KH-550, polyethyleneimine, polyetheramine and glutaraldehyde, heat to 55-65° C., stir at a speed of 400-600 rpm for 3-5 hours, wash, and vacuum dry to obtain modified EPDM particles.

[0009] Preferably, in step (1), the weight ratio of EPDM particles, silane coupling agent KH-570, dicumyl peroxide and cyclohexanone is 8-12:0.08-0.12:0.03-0.08:80-120.

[0010] Preferably, the average particle size of the EPDM particles in step (1) is 1.5-2.2 mm, and the ethylene content is 50 wt%-60 wt%.

[0011] Preferably, the weight average molecular weight of the polyethyleneimine in step (2) is 1700-1900.

[0012] Preferably, the weight average molecular weight of the polyetheramine in step (2) is 300-500.

[0013] Preferably, in step (2), the weight ratio of the EPDM particles with trimethoxysilane grafted on the surface, deionized water, ethanol, silane coupling agent KH-550, polyethyleneimine, polyetheramine and glutaraldehyde is 8-12:40-60:15-25:0.8-1.2:4-6:0.5-1.5:1.5-2.5.

[0014] Furthermore, the glue is polyurethane glue.

[0015] Furthermore, the preparation steps of the glue are as follows: adding polytetramethylene glycol to a reaction kettle, heating to 78-82°C for dehydration treatment for 1.5-2.5h, then adding isophorone diisocyanate, heating to 85-90°C for reaction for 2-4h to obtain a prepolymer; after cooling the prepolymer to 40-50°C, adding nano calcium carbonate and 0.3-1kg hindered amine light stabilizer, stirring at 1000-1500rpm for 10-20min, then adding aluminum acetylacetonate, and continuing to stir for 3-8min to form glue.

[0016] Preferably, the weight average molecular weight of the polytetramethylene ether diol is 1800-2200.

[0017] Preferably, the weight ratio of the polytetramethylene glycol, isophorone diisocyanate, nano calcium carbonate, hindered amine light stabilizer and aluminum acetylacetonate is 80-120:12-18:10-20:0.3-1:4-6.

[0018] Furthermore, the present invention also provides a method for preparing a yellowing-resistant glue plastic track, which is characterized in that it comprises the following steps: putting modified EPDM particles and glue into a planetary mixer, mixing at 35-45°C for 5-10 minutes to obtain a mixture, spreading the mixture on a concrete base surface, reciprocatingly rolling the mixture with a roller for 2-4 times, and curing at room temperature for 20-28 hours to form a yellowing-resistant glue plastic track with a thickness of 10-14 mm.

[0019] Beneficial effects of the present invention:

[0020] The present invention achieves multiple performance breakthroughs in the plastic track material system by modifying EPDM particles through innovative interface modification technology. First, by constructing a gradient chemical bonding interface, the problem of weak interface bonding between EPDM particles and glue in traditional materials is effectively solved, so that external force loads can be evenly transmitted through the three-dimensional cross-linked network, significantly improving the material's ability to resist stress concentration and overall structural stability. Secondly, the unique rigid-flexible synergistic structural design achieves a balance between high strength and high elasticity at the molecular level. The rigid components enhance mechanical strength by forming an interpenetrating network through intermolecular entanglement, and the flexible segments absorb impact energy through a reversible bonding mechanism, so that the material has excellent deformation resistance and energy dissipation characteristics under dynamic loads.

[0021] The multi-level interface protection system provided by the present invention greatly improves the weather resistance of the material through the synergistic effect of chemical bonding and physical shielding. The dense silane layer on the surface of the EPDM particles can effectively block the erosion of ultraviolet rays and environmental media, delay the oxidative degradation of the molecular chain, and keep the color stability of the material for a long time. Overall, the present invention significantly extends the service life of the product and reduces maintenance costs while improving the comprehensive performance of the material, providing an innovative solution for high-performance sports venue materials. DETAILED DESCRIPTION

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0023] Embodiment 1:

[0024] (1) 8 kg of EPDM particles (average particle size 1.5 mm, ethylene content 58 wt%) were immersed in 80 kg of cyclohexanone solution containing 0.08 kg of silane coupling agent KH-570 and 0.03 kg of diisopropylbenzene peroxide, and immersed at 35° C. for 1.5 h, then heated to 115° C., stirred for reaction for 2 h, centrifuged, washed with acetone, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface;

[0025] (2) 8 kg of EPDM particles with trimethoxysilane grafted on the surface were added to 40 kg of deionized water and 15 kg of ethanol, and then 0.8 kg of silane coupling agent KH-550, 4 kg of polyethyleneimine (weight average molecular weight 1800), 0.5 kg of polyetheramine (weight average molecular weight 400) and 1.5 kg of glutaraldehyde were added, the temperature was raised to 55 ° C, and the mixture was stirred at a speed of 400 rpm for 3 hours. The mixture was washed with deionized water and ethanol for 3 times, and vacuum dried to obtain modified EPDM particles;

[0026] (3) 80 kg of polytetramethylene glycol (weight average molecular weight 2000) was added to the reaction kettle, the temperature was raised to 78° C. for dehydration treatment for 1.5 h, and then 12 kg of isophorone diisocyanate was added, the temperature was raised to 85° C. for reaction for 2 h to obtain a prepolymer;

[0027] (4) After the prepolymer is cooled to 40°C, 10 kg of nano calcium carbonate (average particle size 50 nm) and 0.3 kg of hindered amine light stabilizer 770 are added, and the mixture is stirred at 1000 rpm for 15 min. Subsequently, 4 kg of aluminum acetylacetonate is added, and stirring is continued for 3 min to form a glue;

[0028] (5) The modified EPDM particles and glue were put into a planetary mixer at a weight ratio of 5:0.8, mixed at 35°C for 5 minutes to obtain a mixture, spread the mixture on the concrete base surface, and rolled it back and forth twice with a roller. After curing at room temperature for 20 hours, a 12 mm thick yellowing-resistant glue plastic track was formed.

[0029] Embodiment 2:

[0030] (1) 10 kg of EPDM particles (average particle size 1.8 mm, ethylene content 58 wt%) were immersed in 100 kg of cyclohexanone solution containing 0.1 kg of silane coupling agent KH-570 and 0.05 kg of diisopropylbenzene peroxide, and immersed at 40° C. for 2 h, then heated to 120° C., stirred for reaction for 3 h, centrifuged, washed with acetone, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface;

[0031] (2) 10 kg of EPDM particles with trimethoxysilane grafted on the surface were added to 50 kg of deionized water and 20 kg of ethanol, and then 1 kg of silane coupling agent KH-550, 5 kg of polyethyleneimine (weight average molecular weight 1800), 1 kg of polyetheramine (weight average molecular weight 400) and 2 kg of glutaraldehyde were added, the temperature was raised to 60° C., stirred at a speed of 500 rpm for 4 h, washed with deionized water and ethanol for 3 times, and vacuum dried to obtain modified EPDM particles;

[0032] (3) 100 kg of polytetramethylene glycol (weight average molecular weight 2000) was added to the reaction kettle, the temperature was raised to 80° C. for dehydration treatment for 2 h, and then 15 kg of isophorone diisocyanate was added, the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

[0033] (4) After the prepolymer is cooled to 45°C, 15 kg of nano calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 are added, and the mixture is stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate is added, and the mixture is stirred for 5 min to form a glue;

[0034] (5) The modified EPDM particles and glue were put into a planetary mixer at a weight ratio of 5:1, mixed at 40°C for 8 minutes to obtain a mixture, spread the mixture on the concrete base surface, and rolled it back and forth three times with a roller. After curing at room temperature for 24 hours, a yellowing-resistant glue plastic track with a thickness of 12 mm was formed.

[0035] Embodiment 3:

[0036] (1) 12 kg of EPDM particles (average particle size 1.5-2.2 mm, ethylene content 58 wt%) were immersed in 120 kg of cyclohexanone solution containing 0.12 kg of silane coupling agent KH-570 and 0.08 kg of diisopropylbenzene peroxide, and immersed at 45° C. for 2.5 h, then heated to 125° C., stirred for reaction for 4 h, centrifuged, washed with acetone, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface;

[0037] (2) 12 kg of EPDM particles with trimethoxysilane grafted on the surface were added to 60 kg of deionized water and 25 kg of ethanol, and then 1.2 kg of silane coupling agent KH-550, 6 kg of polyethyleneimine (weight average molecular weight 1800), 1.5 kg of polyetheramine (weight average molecular weight 400) and 2.5 kg of glutaraldehyde were added, the temperature was raised to 65 ° C, and the mixture was stirred at a speed of 600 rpm for 5 hours. The mixture was washed with deionized water and ethanol for 3 times, and vacuum dried to obtain modified EPDM particles;

[0038] (3) 120 kg of polytetramethylene glycol (weight average molecular weight 2000) was added to the reaction kettle, the temperature was raised to 82° C. for dehydration treatment for 2.5 h, and then 18 kg of isophorone diisocyanate was added, the temperature was raised to 90° C. for reaction for 4 h to obtain a prepolymer;

[0039] (4) After the prepolymer is cooled to 50°C, 20 kg of nano calcium carbonate (average particle size 50 nm) and 1 kg of hindered amine light stabilizer 770 are added, and stirred at 1500 rpm for 15 min. Subsequently, 6 kg of aluminum acetylacetonate is added, and stirring is continued for 3-8 min to form a glue;

[0040] (5) The modified EPDM particles and glue were put into a planetary mixer at a weight ratio of 5:1.2, mixed at 45°C for 10 minutes to obtain a mixture, spread the mixture on the concrete base surface, and rolled it back and forth 4 times with a roller. After curing at room temperature for 28 hours, a 12 mm thick yellowing-resistant glue plastic track was formed.

[0041] Comparative Example 1:

[0042] The difference between Comparative Example 1 and Example 2 is that: the EPDM particles with trimethoxysilane grafted on the surface in step (2) are replaced with EPDM particles;

[0043] The specific steps are as follows:

[0044] (1) 10 kg of EPDM particles (average particle size 1.8 mm, ethylene content 58 wt%) were added to 50 kg of deionized water and 20 kg of ethanol, and then 1 kg of silane coupling agent KH-550, 5 kg of polyethyleneimine (weight average molecular weight 1800), 1 kg of polyetheramine (weight average molecular weight 400) and 2 kg of glutaraldehyde were added, the temperature was raised to 60° C., stirred at a speed of 500 rpm for 4 h, washed with deionized water and ethanol for 3 times, and vacuum dried to obtain modified EPDM particles;

[0045] (2) adding 100 kg of polytetramethylene glycol (weight average molecular weight 2000) into a reaction kettle, heating to 80° C. for dehydration treatment for 2 h, then adding 15 kg of isophorone diisocyanate, heating to 85° C. for reaction for 3 h, and obtaining a prepolymer;

[0046] (3) After the prepolymer is cooled to 45°C, 15 kg of nano calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 are added, and the mixture is stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate is added, and the mixture is stirred for 5 min to form a glue;

[0047] (4) The modified EPDM particles and glue were put into a planetary mixer at a weight ratio of 5:1, mixed at 40°C for 8 minutes to obtain a mixture, spread the mixture on the concrete base surface, and rolled it back and forth three times with a roller. After curing at room temperature for 24 hours, a glue plastic track with a thickness of 12 mm was formed.

[0048] Comparative Example 2:

[0049] The difference between Comparative Example 2 and Example 2 is that the modified EPDM particles in step (5) are replaced with EPDM particles with trimethoxysilane grafted on the surface;

[0050] The specific steps are as follows:

[0051] (1) 10 kg of EPDM particles (average particle size 1.8 mm, ethylene content 58 wt%) were immersed in 100 kg of cyclohexanone solution containing 0.1 kg of silane coupling agent KH-570 and 0.05 kg of diisopropylbenzene peroxide, and immersed at 40° C. for 2 h, then heated to 120° C., stirred for reaction for 3 h, centrifuged, washed with acetone, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface;

[0052] (2) adding 100 kg of polytetramethylene glycol (weight average molecular weight 2000) into a reaction kettle, heating to 80° C. for dehydration treatment for 2 h, then adding 15 kg of isophorone diisocyanate, heating to 85° C. for reaction for 3 h, and obtaining a prepolymer;

[0053] (3) After the prepolymer is cooled to 45°C, 15 kg of nano calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 are added, and the mixture is stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate is added, and the mixture is stirred for 5 min to form a glue;

[0054] (4) EPDM particles with surface grafted trimethoxysilane and glue are put into a planetary mixer at a weight ratio of 5:1, mixed at 40°C for 8 minutes to obtain a mixture, spread the mixture on the concrete base surface, and reciprocately rolled 3 times with a roller. After curing at room temperature for 24 hours, a glue plastic track with a thickness of 12 mm is formed.

[0055] Comparative Example 3:

[0056] The difference between Comparative Example 3 and Example 2 is that the modified EPDM particles in step (5) are replaced with EPDM particles;

[0057] The specific steps are as follows:

[0058] (1) 100 kg of polytetramethylene glycol (weight average molecular weight 2000) was added to a reaction kettle, the temperature was raised to 80° C. for dehydration treatment for 2 h, and then 15 kg of isophorone diisocyanate was added, the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

[0059] (2) After the prepolymer is cooled to 45°C, 15 kg of nano calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 are added, and the mixture is stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate is added, and the mixture is stirred for 5 min to form a glue;

[0060] (3) EPDM particles and glue are put into a planetary mixer at a weight ratio of 5:1, mixed at 40°C for 8 minutes to obtain a mixture, spread the mixture on the concrete base surface, and reciprocate and roll it three times with a roller. After curing at room temperature for 24 hours, a glue plastic track with a thickness of 12 mm is formed.

[0061] Comparative Example 4:

[0062] The difference between Comparative Example 4 and Example 2 is that: no polyethyleneimine is added in Comparative Example (2);

[0063] The specific steps are as follows:

[0064] (1) 10 kg of EPDM particles (average particle size 1.8 mm, ethylene content 58 wt%) were immersed in 100 kg of cyclohexanone solution containing 0.1 kg of silane coupling agent KH-570 and 0.05 kg of diisopropylbenzene peroxide, and immersed at 40° C. for 2 h, then heated to 120° C., stirred for reaction for 3 h, centrifuged, washed with acetone, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface;

[0065] (2) 10 kg of EPDM particles with trimethoxysilane grafted on the surface were added to 50 kg of deionized water and 20 kg of ethanol, and then 1 kg of silane coupling agent KH-550, 6 kg of polyetheramine (weight average molecular weight 400) and 2 kg of glutaraldehyde were added, the temperature was raised to 60° C., stirred at a speed of 500 rpm for 4 h, washed with deionized water and ethanol for 3 times, and vacuum dried to obtain modified EPDM particles;

[0066] (3) 100 kg of polytetramethylene glycol (weight average molecular weight 2000) was added to the reaction kettle, the temperature was raised to 80° C. for dehydration treatment for 2 h, and then 15 kg of isophorone diisocyanate was added, the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

[0067] (4) After the prepolymer is cooled to 45°C, 15 kg of nano calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 are added, and the mixture is stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate is added, and the mixture is stirred for 5 min to form a glue;

[0068] (5) The modified EPDM particles and glue were put into a planetary mixer at a weight ratio of 5:1, mixed at 40°C for 8 minutes to obtain a mixture, spread the mixture on the concrete base surface, and rolled it back and forth three times with a roller. After curing at room temperature for 24 hours, a glue plastic track with a thickness of 12 mm was formed.

[0069] Comparative Example 5:

[0070] The difference between Comparative Example 5 and Example 2 is that: no polyetheramine is added in Comparative Example (2);

[0071] The specific steps are as follows:

[0072] (1) 10 kg of EPDM particles (average particle size 1.8 mm, ethylene content 58 wt%) were immersed in 100 kg of cyclohexanone solution containing 0.1 kg of silane coupling agent KH-570 and 0.05 kg of diisopropylbenzene peroxide, and immersed at 40° C. for 2 h, then heated to 120° C., stirred for reaction for 3 h, centrifuged, washed with acetone, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface;

[0073] (2) 10 kg of EPDM particles with trimethoxysilane grafted on the surface were added to 50 kg of deionized water and 20 kg of ethanol, and then 1 kg of silane coupling agent KH-550, 6 kg of polyethyleneimine (weight average molecular weight 1800) and 2 kg of glutaraldehyde were added, the temperature was raised to 60° C., stirred at a speed of 500 rpm for 4 h, washed with deionized water and ethanol for 3 times, and vacuum dried to obtain modified EPDM particles;

[0074] (3) 100 kg of polytetramethylene glycol (weight average molecular weight 2000) was added to the reaction kettle, the temperature was raised to 80° C. for dehydration treatment for 2 h, and then 15 kg of isophorone diisocyanate was added, the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

[0075] (4) After the prepolymer is cooled to 45°C, 15 kg of nano calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 are added, and the mixture is stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate is added, and the mixture is stirred for 5 min to form a glue;

[0076] (5) The modified EPDM particles and glue were put into a planetary mixer at a weight ratio of 5:1, mixed at 40°C for 8 minutes to obtain a mixture, spread the mixture on the concrete base surface, and rolled it back and forth three times with a roller. After curing at room temperature for 24 hours, a glue plastic track with a thickness of 12 mm was formed.

[0077] Performance Test:

[0078] Tensile strength and elongation at break: measured according to GB / T 528-2009, 5 dumbbell-shaped specimens (thickness 2.0±0.2mm) were cut from the finished runway and tested using a universal material testing machine at a tensile speed of 500mm / min. The results are shown in Table 1;

[0079] Yellowing resistance test: According to GB / T 14522-2008, the sample is placed in an aging box equipped with UVA-340 lamps at 0.76W / m 2 Irradiation intensity, continuous exposure at 60°C for 500 h, after aging, the ΔE value was measured using a colorimeter to quantify the degree of yellowing, and the results are shown in Table 1;

[0080] Durability test: The compression set was determined according to GB / T 7759-2015. The compression set specimen was placed in a 70°C environment and subjected to a 25% compression rate for 24 hours. The thickness change rate was measured after cooling. The wear resistance was determined according to GB / T9867-2008. A CS-10 wear wheel was used to run 1000 revolutions under a load of 10N. The volume difference before and after wear was measured. The results are shown in Table 1.

[0081] Table 1 Performance test results

[0082]

[0083]

[0084] Data Analysis:

[0085] It can be seen from the data of Examples 1-3 that the plastic track prepared by the present invention has high mechanical properties and yellowing resistance, the compression permanent deformation is as low as 25%, the volume wear rate after running 1000 revolutions under a load of 10N is as low as 1.5%, and it has excellent durability, achieving multiple breakthroughs in mechanical properties, weather resistance and durability.

[0086] From the data of Example 2 and Comparative Example 1, it can be seen that the EPDM particles in Comparative Example 1 are not grafted and modified, which makes it difficult for polyethyleneimine and polyetheramine to be evenly wrapped on the surface of EPDM particles, resulting in poor bonding with the glue matrix, and stress concentration points are easily formed at the interface. In Example 2, the chemical bonding interface constructed by silane coupling agent, polyethyleneimine and polyetheramine significantly improves the compatibility of the two phases, so that the external force load is evenly transmitted through the chemical bond network, avoiding local fracture and causing overall failure. Branched polyethyleneimine and linear polyetheramine simultaneously construct rigid and flexible regions in EPDM particles. This rigid-flexible synergistic effect not only enhances tensile strength, but also improves the ability to resist compression deformation by inhibiting molecular chain slippage. In addition, the silane layer formed on the surface acts as an ultraviolet shielding layer, effectively blocking the damage of high-energy photons to the molecular chain, reducing the rate of photooxidation reaction, thereby significantly improving the yellowing resistance.

[0087] From the data of Example 2 and Comparative Example 2 in Table 1, it can be seen that Comparative Example 2 only uses a single layer of silane grafting, while Example 2 forms a gradient functional interface through secondary modification of polyethyleneimine and polyetheramine. The amine groups of polyethyleneimine and polyetheramine form crosslinks with the amine groups in silane under the action of glutaraldehyde to construct a branched supramolecular network, greatly increase the interface bonding area, further enhance the thermal stability of the interface layer, and prevent interface degradation during high-temperature processing. At the same time, the flexible chain segments of polyetheramine are interspersed in the crosslinked network, effectively absorbing impact energy, so that the material can still maintain the ductility of the molecular chain when subjected to high tensile loads.

[0088] From the data of Example 2 and Comparative Example 3 in Table 1, it can be seen that Comparative Example 3 directly uses unmodified EPDM particles, resulting in only physical adsorption between the particles and the glue matrix, and the interface bonding force is weak. In contrast, Example 2 constructs a multi-level interface structure through two-step modification, and the unmodified EPDM particles lack a stable interface protective layer, which makes the glue matrix more susceptible to photo-oxidative degradation, accelerating yellowing and mechanical property degradation.

[0089] It can be seen from the data of Example 2 and Comparative Example 4 in Table 1 that the lack of polyethyleneimine in Comparative Example 4 results in a higher flexibility of the interface modification layer, while in Example 2, polyethyleneimine forms a three-dimensional interpenetrating network through intermolecular entanglement, and its high-density amine group not only forms a covalent bond with the silane layer, but also undergoes in-situ polymerization with the isocyanate groups in the glue to generate micro-regions with energy dissipation characteristics at the interface. This unique "rigid and flexible" structure enables the material to absorb impact energy through micro-region deformation when subjected to dynamic loads, while maintaining the overall structural integrity.

[0090] From the data of Example 2 and Comparative Example 5 in Table 2, it can be seen that the lack of polyetheramine in Comparative Example 5 leads to insufficient flexibility of the interface modification layer, while the flexible ether bond of polyetheramine in Example 2 forms a complementary structure with the rigid segment of polyethyleneimine. The long chain characteristics of polyetheramine can be interspersed in the cross-linked network, absorbing impact energy through molecular chain entanglement, while its terminal amine group undergoes a cross-linking reaction with glutaraldehyde. This design allows the material to dissipate energy through reversible bond breakage-reorganization during the stretching process, maintaining high strength and improving elongation at break.

[0091] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

Claims

1. A yellowing-resistant glue plastic track, characterized in that: Prepared by modified EPDM particles and glue in a weight ratio of 5:0.8-1.2; The preparation method of the modified EPDM particles is as follows: (1) EPDM particles are immersed in a cyclohexanone solution containing a silane coupling agent KH-570 and diisopropylbenzene peroxide at 35-45° C. for 1.5-2.5 hours, then heated to 115-125° C., stirred for reaction for 2-4 hours, centrifuged, washed, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface; (2) adding EPDM particles with trimethoxysilane grafted on the surface to deionized water and ethanol, and then adding silane coupling agent KH-550, polyethyleneimine, polyetheramine and glutaraldehyde, heating to 55-65° C., stirring at a speed of 400-600 rpm for 3-5 hours, washing, and vacuum drying to obtain modified EPDM particles; In the step (1), the weight ratio of EPDM particles, silane coupling agent KH-570, dicumyl peroxide and cyclohexanone is 8-12:0.08-0.12:0.03-0.08:80-120; In the step (2), the weight ratio of the EPDM particles with trimethoxysilane grafted on the surface, deionized water, ethanol, silane coupling agent KH-550, polyethyleneimine, polyetheramine and glutaraldehyde is 8-12:40-60:15-25:0.8-1.2:4-6:0.5-1.5:1.5-2.5; The glue is polyurethane glue.

2. The yellowing-resistant glue plastic track according to claim 1, characterized in that: The preparation steps of the glue are as follows: adding polytetramethylene glycol to a reaction kettle, heating to 78-82° C. for dehydration treatment for 1.5-2.5 hours, then adding isophorone diisocyanate, heating to 85-90° C. for reaction for 2-4 hours to obtain a prepolymer; cooling the prepolymer to 40-50° C., adding nano calcium carbonate and 0.3-1 kg of hindered amine light stabilizer, stirring at a speed of 1000-1500 rpm for 10-20 minutes, then adding aluminum acetylacetonate, and continuing to stir for 3-8 minutes to form glue.

3. The yellowing-resistant glue plastic track according to claim 2, characterized in that: The weight average molecular weight of the polytetramethylene ether diol is 1800-2200.

4. The yellowing-resistant glue plastic track according to claim 2, characterized in that: The weight ratio of the polytetramethylene glycol, isophorone diisocyanate, nano calcium carbonate, hindered amine light stabilizer and aluminum acetylacetonate is 80-120:12-18:10-20:0.3-1:4-6.

5. The yellowing-resistant glue plastic track according to claim 1, characterized in that: The average particle size of the EPDM particles in step (1) is 1.5-2.2 mm, and the ethylene content is 50 wt%-60 wt%.

6. The yellowing-resistant glue plastic track according to claim 1, characterized in that: The weight average molecular weight of polyethyleneimine in the step (2) is 1700-1900.

7. The yellowing-resistant glue plastic track according to claim 1, characterized in that: The weight average molecular weight of the polyetheramine in step (2) is 300-500.

8. A method for preparing the yellowing-resistant glue plastic track according to any one of claims 1 to 7, characterized in that: The following steps are involved: Put the modified EPDM particles and glue into a planetary mixer, mix at 35-45℃ for 5-10min to obtain a mixture, spread the mixture on the concrete base surface, use a roller to reciprocate 2-4 times, and cure at room temperature for 20-28h to form a yellowing-resistant glue plastic track with a thickness of 10-14mm.

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