Yellowing-resistant glue plastic runway and preparation method thereof

Abstract

The present invention relates to the technical field of plastic runways, and in particular to a yellowing-resistant glue plastic runway and a preparation method thereof. The runway is made by compounding modified EPDM particles and polyurethane glue in a weight ratio of 5:0.8-1.2. An innovative two-step interface modification technology is adopted: first, trimethoxysilane active groups are grafted on the EPDM surface through the silane coupling agent KH-570, and then a three-dimensional cross-linked network is constructed with KH-550, polyethyleneimine, and polyetheramine. The glue system adopts polytetramethylene ether glycol and isophorone diisocyanate to synthesize a prepolymer, and compounded with a nano-calcium carbonate / hindered amine light stabilizer / aluminum acetylacetonate synergistic system. This technology significantly enhances the particle-matrix interface bonding force through gradient chemical bonding. The resulting runway has high durability and is particularly suitable for the construction of sports venues in high-latitude areas with strong ultraviolet rays.

Description

Technical Field

[0001] The present 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 has low surface energy characteristics, resulting in poor interfacial compatibility with the polar polyurethane glue matrix. In traditional processes, EPDM particles and glue are only combined through physical adsorption. This weak interaction is prone to failure under environmental stresses such as wet-heat cycles and freeze-thaw cycles, causing interfacial debonding, delamination 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 1.5 MPa) and high compression set (generally more than 35%). In addition, long-term ultraviolet radiation will induce photooxidative breakage of the urethane bonds in the glue molecular chain, and conventional anti-aging agents, due to the lack of chemical bonding with the matrix, are prone to migrate to the surface and be washed away by rainwater, causing the material to yellow (ΔE value > 6) and accelerated degradation of 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 groups with 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 chain 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 strength 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) Immersing EPDM particles 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 heating to 115-125°C, stirring for 2-4 hours, centrifuging, washing, and vacuum drying to obtain EPDM particles with trimethoxysilane grafted on the surface;

[0008] (2) EPDM particles with surface grafted trimethoxysilane are added to deionized water and ethanol, and then silane coupling agent KH-550, polyethyleneimine, polyetheramine and glutaraldehyde are added, the temperature is raised to 55-65°C, and the mixture is stirred at a speed of 400-600 rpm for 3-5 hours, washed, and vacuum dried 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 reactor, 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; after cooling the prepolymer to 40-50°C, adding nano-calcium carbonate and 0.3-1 kg of hindered amine light stabilizer, stirring at 1000-1500 rpm for 10-20 minutes, then adding aluminum acetylacetonate, and continuing to stir for 3-8 minutes to form glue.

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

[0017] Preferably, the weight ratio of the polytetramethylene ether 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 includes 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, using a roller to reciprocate 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 this invention significantly improves the material's weather resistance through the synergistic effects of chemical bonding and physical shielding. The dense silane layer on the surface of the EPDM particles effectively blocks UV rays and environmental damage, slowing the oxidative degradation of the molecular chain and maintaining the material's color stability over time. Overall, this invention significantly extends the product's service life and reduces maintenance costs while improving the material's overall performance, providing an innovative solution for high-performance sports surface 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 with reference to specific embodiments.

[0023] Example 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 the mixture was immersed at 35°C for 1.5 h. The mixture was then heated to 115°C and stirred for 2 h. The mixture was 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 surface grafted trimethoxysilane 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 stirred at a speed of 400 rpm for 3 hours. The mixture was washed with deionized water and ethanol three 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 reactor, heated to 78 ° C for dehydration for 1.5 h, and then 12 kg of isophorone diisocyanate was added, and the temperature was raised to 85 ° C for reaction for 2 h to obtain a prepolymer;

[0027] (4) After cooling the prepolymer to 40°C, 10 kg of nano-calcium carbonate (average particle size 50 nm) and 0.3 kg of hindered amine light stabilizer 770 were added and stirred at 1000 rpm for 15 min. Subsequently, 4 kg of aluminum acetylacetonate was added and stirred 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] Example 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 the mixture was immersed at 40°C for 2 h. The mixture was then heated to 120°C and stirred for 3 h. The mixture was 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, and the mixture was stirred at a speed of 500 rpm for 4 hours. The mixture was 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 reactor, heated to 80° C. for dehydration for 2 h, and then 15 kg of isophorone diisocyanate was added, and the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

[0033] (4) After cooling the prepolymer to 45°C, 15 kg of nano-calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 were added and stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate was added and 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 3 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] Example 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 the mixture was immersed at 45°C for 2.5 h. The mixture was then heated to 125°C and stirred for 4 h. The mixture was 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 stirred at a speed of 600 rpm for 5 h. The mixture was washed with deionized water and ethanol three 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 reactor, heated to 82° C. for dehydration for 2.5 h, and then 18 kg of isophorone diisocyanate was added, and the temperature was raised to 90° C. for reaction for 4 h to obtain a prepolymer;

[0039] (4) After cooling the prepolymer to 50°C, 20 kg of nano-calcium carbonate (average particle size 50 nm) and 1 kg of hindered amine light stabilizer 770 were added and stirred at 1500 rpm for 15 min. Subsequently, 6 kg of aluminum acetylacetonate was added and stirred 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, followed by 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. The mixture was heated to 60°C and stirred at 500 rpm for 4 h. The mixture was washed three times with deionized water and ethanol, and vacuum dried to obtain modified EPDM particles.

[0045] (2) 100 kg of polytetramethylene glycol (weight average molecular weight 2000) was added to the reactor, heated to 80° C. for dehydration treatment for 2 h, and then 15 kg of isophorone diisocyanate was added, and the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

[0046] (3) After cooling the prepolymer to 45°C, 15 kg of nano-calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 were added and stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate was added and 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 3 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 the mixture was immersed at 40°C for 2 h. The mixture was then heated to 120°C and stirred for 3 h. The mixture was centrifuged, washed with acetone, and vacuum dried to obtain EPDM particles with trimethoxysilane grafted on the surface.

[0052] (2) 100 kg of polytetramethylene glycol (weight average molecular weight 2000) was added to the reactor, heated to 80° C. for dehydration treatment for 2 h, and then 15 kg of isophorone diisocyanate was added, and the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

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

[0054] (4) EPDM particles with surface grafted trimethoxysilane 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 3 times with a roller. After curing at room temperature for 24 hours, a glue plastic track with a thickness of 12 mm was 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 reactor, heated to 80° C. for dehydration for 2 h, and then 15 kg of isophorone diisocyanate was added, and the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

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

[0060] (3) 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 3 times with a roller. After curing at room temperature for 24 hours, a glue plastic track with a thickness of 12 mm was formed.

[0061] Comparative Example 4:

[0062] The difference between Comparative Example 4 and Example 2 is that: no polyethyleneimine was 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 the mixture was immersed at 40°C for 2 h. The mixture was then heated to 120°C and stirred for 3 h. The mixture was 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 surface grafted trimethoxysilane 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 mixture was heated to 60 ° C and stirred at a speed of 500 rpm for 4 h. The mixture was washed with deionized water and ethanol three 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 reactor, heated to 80° C. for dehydration for 2 h, and then 15 kg of isophorone diisocyanate was added, and the temperature was raised to 85° C. for reaction for 3 h to obtain a prepolymer;

[0067] (4) After cooling the prepolymer to 45°C, 15 kg of nano-calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 were added and stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate was added and 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 3 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 the mixture was immersed at 40°C for 2 h. The mixture was then heated to 120°C and stirred for 3 h. The mixture was 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 surface grafted trimethoxysilane 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 mixture was heated to 60°C and stirred at 500 rpm for 4 h. The mixture was washed three times with deionized water and ethanol, and vacuum dried to obtain modified EPDM particles.

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

[0075] (4) After cooling the prepolymer to 45°C, 15 kg of nano-calcium carbonate (average particle size 50 nm) and 0.5 kg of hindered amine light stabilizer 770 were added and stirred at 1200 rpm for 15 min. Subsequently, 5 kg of aluminum acetylacetonate was added and 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 3 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 testing:

[0078] Tensile strength and elongation at break: Determined according to GB / T 528-2009. Five dumbbell-shaped specimens (thickness 2.0 ± 0.2 mm) were cut from the finished runway and tested using a universal material testing machine at a tensile speed of 500 mm / 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 The irradiation intensity was 60°C for 500 h. After aging, the ΔE value was measured using a colorimeter to quantify the degree of yellowing. The results are shown in Table 1.

[0080] Durability testing: Compression set was determined according to GB / T 7759-2015. The compression set specimens were placed at 70°C and subjected to a 25% compression ratio for 24 hours. After cooling, the thickness change rate was measured. Abrasion resistance was determined according to GB / T 9867-2008. A CS-10 abrasion wheel was used for 1000 revolutions under a load of 10N. The volume difference before and after abrasion 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%, and the volume wear rate after running 1000 revolutions under a load of 10N is as low as 1.5%. It has excellent durability and has achieved 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 the EPDM particles, resulting in poor bonding with the glue matrix and the formation of stress concentration points at the interface. In Example 2, the chemically bonded 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 the EPDM particles. This rigid-flexible synergistic effect not only enhances tensile strength, but also enhances compression deformation resistance by suppressing molecular chain slippage. In addition, the silane layer formed on the surface acts as an ultraviolet shielding layer, effectively blocking the destruction of the molecular chain by high-energy photons, reducing the photooxidation reaction rate, thereby significantly improving the yellowing resistance.

[0087] As shown in Table 1, the data for Example 2 and Comparative Example 2 demonstrate that Comparative Example 2 utilizes only a single layer of silane grafting, while Example 2 utilizes secondary modification with polyethyleneimine and polyetheramine to form a gradient functional interface. Under the action of glutaraldehyde, the amine groups of the polyethyleneimine and polyetheramine crosslink with the amino groups of the silane, forming a dendritic supramolecular network. This significantly increases the interfacial bonding area, further enhancing the thermal stability of the interfacial layer and preventing degradation during high-temperature processing. Furthermore, the flexible segments of the polyetheramine, interspersed within the crosslinked network, effectively absorb impact energy, enabling the material to maintain molecular ductility even under high tensile loads.

[0088] The data from Example 2 and Comparative Example 3 in Table 1 show that Comparative Example 3 uses unmodified EPDM particles directly, resulting in a weak interfacial bond between the particles and the adhesive matrix, relying solely on physical adsorption. In contrast, Example 2 utilizes a two-step modification process to create a multi-level interface structure. Furthermore, the unmodified EPDM particles lack a stable interfacial protective layer, making the adhesive matrix more susceptible to photooxidative degradation, accelerating yellowing and mechanical property degradation.

[0089] From the data of Example 2 and Comparative Example 4 in Table 1, it can be seen 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. Its high-density amine groups not only form covalent bonds with the silane layer, but also undergo in situ polymerization with the isocyanate groups in the glue, generating 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 integrity of the overall structure.

[0090] The data from Example 2 and Comparative Example 5 in Table 2 show that the lack of polyetheramine in Comparative Example 5 results in insufficient flexibility in the interface-modified layer. In contrast, the flexible ether bonds of the polyetheramine in Example 2 form a complementary structure with the rigid polyethyleneimine segments. The long chains of polyetheramine allow them to interweave within the crosslinked network, absorbing impact energy through molecular chain entanglement. Simultaneously, their terminal amine groups undergo a crosslinking reaction with glutaraldehyde. This design allows the material to dissipate energy during stretching through reversible bond breakage and recombination, maintaining high strength while 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. Within the scope 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 from 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) Immersing EPDM particles 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 heating to 115-125°C, stirring for 2-4 hours, centrifuging, washing, and vacuum drying to obtain EPDM particles with trimethoxysilane grafted on the surface; (2) adding EPDM particles with surface grafted trimethoxysilane to deionized water and ethanol, 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 the mixture to 78-82° C. and performing dehydration treatment for 1.5-2.5 hours, then adding isophorone diisocyanate, heating the mixture to 85-90° C. and reacting the mixture 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 a hindered amine light stabilizer, stirring the mixture at a speed of 1000-1500 rpm for 10-20 minutes, then adding aluminum acetylacetonate, and continuing stirring for 3-8 minutes to form the glue.

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

4. The yellowing-resistant glue plastic track according to claim 2, characterized in that: The weight ratio of the polytetramethylene ether 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 the 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 a 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 5-10 minutes 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 20-28 hours to form a yellowing-resistant glue plastic track with a thickness of 10-14mm.

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