Hot melt adhesive with high initial adhesion and high heat resistance, process, home appliance back plate and application of hot melt adhesive

Abstract

The invention relates to a hot melt adhesive with high initial adhesion and high heat resistance, a process, a home appliance back plate and application thereof. The hot melt adhesive is prepared from the following raw materials in parts by mass: 30 to 50 parts of hydrogenated SBC, 40 to 60 parts of tackifying resin with a high softening point, 5 to 15 parts of heat-resistant naphthenic oil, 5 to 15 parts of nano aluminum oxide, 0.1 to 0.5 part of a thermal activation cross-linking agent, 0.5 to 1.5 parts of an antioxidant and 0.5 to 1.5 parts of a light stabilizer, the softening point of the tackifying resin with the high softening point is 90-150 DEG C. According to the scheme, the tackifying resin with the high softening point, the heat-resistant naphthenic oil and the nano aluminum oxide are synergistically compounded, so that a hot melt adhesive system with high initial viscosity and high heat resistance is constructed, and the problem that a plate body of a household appliance is prone to glue failure under long-term thermal load is solved.

Description

Technical Field

[0001] This invention relates to the field of hot melt adhesives, and more particularly to a hot melt adhesive with both high initial tack and high heat resistance, its process, and its applications in home appliance back panels. Background Technology

[0002] When home appliances are in operation, the heat generated by components such as backlight modules and circuit boards fluctuates periodically. Therefore, the heat-melting adhesives commonly used in home appliances are prone to a decrease in cohesion during repeated thermal expansion and contraction, especially at high temperatures where they struggle to maintain sufficient bond strength. For example, the internal temperature of a TV back panel often reaches 85-100℃ during high-power operation; while traditional EVA-based hot melt adhesives typically have a softening point below 90℃ and cannot withstand sustained high temperatures. When the temperature approaches the softening point, the adhesive layer softens and flows, leading to stress imbalance at the bonding interface and ultimately, delamination.

[0003] Traditional TV back panels use EVA-based hot melt adhesive and SBC hot melt adhesive for bonding. However, traditional EVA-based hot melt adhesive has poor heat resistance, easily causing the TV back panel to delaminate under long-term heat load. High-end TVs, operating at high power, typically reach internal temperatures of 85-100℃ or even higher, which is close to or exceeds the softening point of SBC hot melt adhesive. The actual operating temperature of high-end TV back panels approaches or exceeds the heat resistance limit of SBC hot melt adhesive. Therefore, using SBC hot melt adhesive alone in high-end TV back panel applications will cause softening and increased fluidity due to temperatures exceeding its softening point, leading to stress imbalance at the bonding interface and ultimately causing delamination. Summary of the Invention

[0004] The purpose of this invention is to propose a hot melt adhesive that combines high initial tack and high heat resistance. It uses hydrogenated SBC as the main polymer and is synergistically compounded with high softening point tackifying resin, heat-resistant naphthenic oil and nano alumina to construct a hot melt adhesive system that combines high initial tack and high heat resistance.

[0005] To achieve this objective, the present invention adopts the following technical solution: A hot melt adhesive that combines high initial tack and high heat resistance comprises the following raw materials in parts by weight: 30-50 parts hydrogenated SBC, 40-60 parts high softening point tackifying resin, 5-15 parts heat-resistant naphthenic oil, 5-15 parts nano alumina, 0.1-0.5 parts heat-activated crosslinking agent, 0.5-1.5 parts antioxidant, and 0.5-1.5 parts light stabilizer; The softening point of the high softening point tackifying resin is 90–150°C.

[0006] Optimally, the high softening point tackifying resin is a hydrogenated petroleum resin.

[0007] Optimally, the high softening point tackifying resin is a hydrogenated terpene resin.

[0008] Optimally, the particle size of the nano-alumina is 10–100 nm.

[0009] Optimally, the thermally activated crosslinking agent is dicumyl peroxide.

[0010] A process for preparing a hot melt adhesive with both high initial tack and high heat resistance, comprising the following steps: Step (1): Place the heat-resistant naphthenic oil and a portion of the high softening point thickening resin in the reaction vessel and stir to allow the high softening point thickening resin to soften initially in the heat-resistant naphthenic oil. Step (2): Slowly add hydrogenated SBC to the reactor and stir until the hydrogenated SBC is completely melted; add the remaining high softening point thickening resin to the reactor and mix evenly. Step (3): Add the nano-alumina slowly in batches to the reactor and stir continuously until the nano-alumina is completely dispersed; Step (4): Cool the reactor to a temperature below the initial decomposition temperature of the thermally activated crosslinking agent; add antioxidant and light stabilizer in sequence and stir until dispersed; slowly add the thermally activated crosslinking agent, mix evenly and then discharge.

[0011] Optimally, the feature is that, in step (3), the reactor is evacuated when nano-alumina is added.

[0012] A back panel for a household appliance, using the aforementioned hot melt adhesive that combines high initial tack and high heat resistance.

[0013] The use of a hot melt adhesive in a television back panel, wherein the hot melt adhesive is the aforementioned hot melt adhesive that combines high initial tack and high heat resistance.

[0014] Compared with the prior art, one of the above technical solutions has the following beneficial effects: This solution provides a hot melt adhesive that combines high initial tack and high heat resistance. It uses hydrogenated SBC as the main polymer and is synergistically compounded with high softening point tackifying resin, heat-resistant naphthenic oil and nano alumina to construct a hot melt adhesive system that combines high initial tack and high heat resistance, thus solving the problem of easy delamination of the panels of home appliances under long-term heat load. Detailed Implementation

[0015] To facilitate understanding of the present invention, a more comprehensive description is provided below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention. Where specific techniques or conditions are not specified in the embodiments, they are performed in accordance with techniques or conditions described in the literature in the art or according to product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0016] A hot melt adhesive that combines high initial tack and high heat resistance comprises the following raw materials in parts by weight: 30-50 parts hydrogenated SBC, 40-60 parts high softening point tackifying resin, 5-15 parts heat-resistant naphthenic oil, 5-15 parts nano alumina, 0.1-0.5 parts heat-activated crosslinking agent, 0.5-1.5 parts antioxidant, and 0.5-1.5 parts light stabilizer; The softening point of the high softening point tackifying resin is 90–150°C.

[0017] This solution provides a hot melt adhesive that combines high initial tack and high heat resistance. It uses hydrogenated SBC as the main polymer and is synergistically compounded with high softening point tackifying resin, heat-resistant naphthenic oil and nano alumina to construct a hot melt adhesive system that combines high initial tack and high heat resistance, thus solving the problem of easy delamination of the panels of home appliances under long-term heat load.

[0018] Specifically, this solution uses hydrogenated SBC (HSBC, hydrogenated styrene-isoprene thermoplastic elastomer) as the main polymer. SBC possesses excellent antioxidant capacity, weather resistance, acid and alkali resistance, and abrasion resistance, but its upper heat resistance limit is insufficient to meet the long-term heat dissipation requirements of televisions. Therefore, this solution uses a high softening point tackifying resin, heat-resistant naphthenic oil, and nano-alumina to improve the heat resistance of the hot melt adhesive. The high softening point tackifying resin, as a small molecule compound, can act as a non-conductive filler. By improving the dispersibility of nano-alumina, it allows the nano-alumina to form a more effective network structure, thereby reducing the percolation threshold. When nano-alumina... Once the percolation threshold is reached, 5–15 parts of nano-alumina can form a three-dimensional continuous thermally conductive network, thereby promoting the function of thermal conduction pathways and providing thermal channels for the hot melt adhesive. This assists in heat dissipation, improving the heat dissipation effect of the hot melt adhesive, shortening the curing time, and enhancing the overall durability of the hot melt adhesive in high-temperature environments. Simultaneously, the high softening point tackifying resin has a softening point of 90–150℃, and it still exhibits a certain hard phase at the hot melt adhesive's melting temperature, thus fixing the position of the nano-alumina and maintaining the thermally conductive network of nano-alumina formed in the molten state. This combination of high softening point tackifying resin, heat-resistant naphthenic oil, and nano-alumina... A system is constructed where a soft matrix supports hard particles. By adjusting the ratio and sequence structure of the soft and hard materials, a microscopically heterogeneous but macroscopically homogeneous system is formed. At room temperature, the hot melt adhesive is dominated by the soft phase, providing initial tack. At high temperatures, the hard phase of the hot melt adhesive plays a role in preventing overall flow and improving heat resistance. A thermally activated crosslinking agent enables the formation of a covalent network through crosslinking, improving thermal stability. Even at temperatures exceeding the Tg of the SBC, the network structure will not melt, and the adhesive layer can still maintain its structure, strength, and modulus, thus withstanding higher operating temperatures. Heat-resistant naphthenic oil is a known component with low volatility and good compatibility with rubber. It possesses excellent compatibility and high-temperature performance, such as KN4006, N4010, KN4010, and 1020 naphthenic oils; antioxidants ensure that the hot melt adhesive maintains stable performance during high-temperature production (melt extrusion) and repeated melting processes, preventing gelation, skinning, and viscosity stability. It also ensures that hot melt adhesive products do not degrade in performance due to slow oxidation during storage (in solid form), extending shelf life. Light stabilizers primarily delay and inhibit the aging and degradation process of hot melt adhesives caused by long-term exposure to light (especially ultraviolet light) and heat, thereby ensuring the structural integrity and long-term reliability of the backing and hot melt adhesive.

[0019] Optimally, the high softening point tackifying resin is a hydrogenated petroleum resin.

[0020] High-softening-point tackifying resins are preferably hydrogenated petroleum resins, with a softening point range of 115-145℃. Hydrogenated petroleum resins improve the tack and wettability of hot melt adhesives, allowing for more thorough contact between the hot melt adhesive and the surface of the adhered objects, thereby enhancing initial bond strength. Compared to ordinary petroleum resins, hydrogenated petroleum resins undergo hydrogenation treatment, removing some unsaturated bonds and improving thermal stability and aging resistance. This makes them more stable in high-temperature environments while maintaining good adhesive properties.

[0021] Optimally, the high softening point tackifying resin is a hydrogenated terpene resin.

[0022] Hydrogenated terpene resins possess excellent wetting, flowability, moldability, and leveling properties, enabling hot melt adhesives to more quickly wet the surfaces of adherends and form a stronger initial bond. Hydrogenated terpene resins remove unsaturated bonds from terpene resins, breaking some of them and improving thermal stability and aging resistance. This makes hydrogenated terpene resins more stable at high temperatures, less prone to thermal degradation, while maintaining good adhesive properties.

[0023] Optimally, the particle size of the nano-alumina is 10–100 nm.

[0024] The particle size of nano-alumina is 10–100 nm, which represents a balance between reinforcing effect and dispersibility and processability. While smaller particle sizes (e.g., <10 nm) theoretically offer better performance, agglomeration and thickening problems worsen dramatically. Larger particle sizes (e.g., >100 nm) result in loss of nano-characteristics, lower specific surface area, and deterioration of functional properties.

[0025] Optimally, the thermally activated crosslinking agent is dicumyl peroxide.

[0026] Dicumyl peroxide is added in the final step of the process. Because it has been pre-cooled to below the decomposition temperature of dicumyl peroxide before addition, the half-life temperature of dicumyl peroxide is about 115–130℃. It generally decomposes effectively to generate active free radicals at temperatures above 140℃. It is relatively stable at lower temperatures and is not prone to premature cross-linking, which is beneficial for storage and processing operations. It is very suitable for applications such as back panels of home appliances.

[0027] A process for preparing a hot melt adhesive with both high initial tack and high heat resistance, comprising the following steps: Step (1): Place the heat-resistant naphthenic oil and a portion of the high softening point thickening resin in the reaction vessel and stir to allow the high softening point thickening resin to soften initially in the heat-resistant naphthenic oil. Step (2): Slowly add hydrogenated SBC to the reactor and stir until the hydrogenated SBC is completely melted; add the remaining high softening point thickening resin to the reactor and mix evenly. Step (3): Add the nano-alumina slowly in batches to the reactor and stir continuously until the nano-alumina is completely dispersed; Step (4): Cool the reactor to a temperature below the initial decomposition temperature of the thermally activated crosslinking agent; add antioxidant and light stabilizer in sequence and stir until dispersed; slowly add the thermally activated crosslinking agent, mix evenly and then discharge.

[0028] Alternatively, in step (3), the reactor is evacuated when nano-alumina is added. Vacuuming the reactor when nano-alumina is added removes air bubbles and trace amounts of moisture. Moisture can cause nanoparticles to agglomerate, destroying their high specific surface area and high surface activity; air bubbles can disrupt the uniform distribution of nanoparticles, reducing the density and mechanical properties of the product.

[0029] A back panel for a household appliance, using the aforementioned hot melt adhesive that combines high initial tack and high heat resistance.

[0030] The back panel of the home appliance can be one of the following: refrigerator back panel, air conditioner back panel, microwave oven back panel, oven back panel, or electric pressure cooker back panel. This solution provides a hot melt adhesive that combines high initial tack and high heat resistance. It uses hydrogenated SBC as the main polymer and is synergistically compounded with high softening point tackifying resin, heat-resistant naphthenic oil, and nano-alumina to construct a hot melt adhesive system that combines high initial tack and high heat resistance, thus solving the problem of easy delamination of the panel under long-term heat load in home appliances.

[0031] The use of a hot melt adhesive in a television back panel, wherein the hot melt adhesive is the aforementioned hot melt adhesive that combines high initial tack and high heat resistance.

[0032] Performance testing: Initial tack: The initial tack was tested according to GB / T 31125-2014 Test Method for Initial Tack of Adhesive Tapes (Ring Method).

[0033] Tackiness: According to GB / T 4851-2014 Test Method for Adhesive Tape Holding Power, the holding power at 70℃ is tested, and it is considered qualified if it exceeds 30 hours.

[0034] Thermal stability: According to GB / T 16998-1997 Determination of Thermal Stability of Hot Melt Adhesives, the test temperature is 150℃ and the test time is 24h. No color change is considered qualified.

[0035] Example A: A process for preparing a hot melt adhesive that combines high initial tack and high heat resistance includes the following steps: Step (1): Heat the reactor to 140°C, add 10 parts of heat-resistant naphthenic oil (Karamay KN4006) and 30 parts of high softening point tackifying resin (hydrogenated petroleum resin, Eastman C-115W), start stirring, so that the high softening point tackifying resin is initially softened in the heat-resistant naphthenic oil.

[0036] Step (2): Slowly add 40 parts of hydrogenated SBC to the reactor, keep the temperature at 150℃, and stir until the hydrogenated SBC is completely melted; add the remaining 20 parts of high softening point tackifying resin (hydrogenated terpene resin, Matsukawa SR125) to the reactor and mix evenly. Step (3): Add 10 parts of nano alumina (60-90nm) slowly in batches to the reactor, control the temperature at 160℃, draw a vacuum (-0.07 MPa), and continue stirring until the nano alumina is completely dispersed to obtain a uniform and smooth colloid. Step (4): Cool the reactor to 110°C; add 0.5 parts of antioxidant (phosphite-based auxiliary antioxidant 168, Rianon) and 0.5 parts of light stabilizer (Tinuvin 326 and Tinuvin 770 in a 1:1 ratio) in sequence, and stir until dispersed; slowly add 0.3 parts of thermally activated crosslinking agent (diisopropylbenzene peroxide, pre-dispersed with a small amount of high softening point tackifying resin), mix evenly, and then discharge.

[0037] Comparative Example A1: Comparative Example A1 follows the same basic steps as Example A, except that nano-alumina was not added in step (3) of Comparative Example A1.

[0038] Comparative Example A2: Comparative Example A2 follows the same basic steps as Example A, except that heat-resistant naphthenic oil was not added in step (1) of Comparative Example A2.

[0039] Comparative Example A3: Comparative Example A3 follows the same basic steps as Example A, except that in steps (1) and (2) of Comparative Example A3, rosin glycerol ester is used instead of high softening point tackifying resin.

[0040] Performance tests were conducted on Example A and Comparative Examples A1-A3, and the results are shown in Table 1. Table 1 - Performance Tests for Example A

[0041] illustrate: 1. Comparing Example A and Comparative Example A1, it can be seen that Comparative Example A1 did not add nano-alumina, while Example A added 10 parts of nano-alumina. The high softening point tackifying resin, heat-resistant naphthenic oil, and nano-alumina in this solution form a soft matrix supporting hard particles. At room temperature, the hot melt adhesive is dominated by the soft phase to provide initial tack. At high temperatures, the hard phase plays a role in preventing overall flow and improving heat resistance. The absence of the hard phase nano-alumina results in a higher initial tack in Comparative Example A1 compared to Example A. At high temperatures, the hard phase of the hot melt adhesive plays a role in preventing overall flow and improving heat resistance; Example A has better holding power and superior thermal stability. Clearly, Comparative Example A1 has insufficient thermal stability compared to Example A, and Example A has better holding power than Comparative Example A1.

[0042] 2. Comparison of Example A and Comparative Example A2 shows that Comparative Example A2 did not add heat-resistant naphthenic oil, while Example A added 10 parts of heat-resistant naphthenic oil. The high softening point tackifying resin, heat-resistant naphthenic oil, and nano-oxidation construct a soft matrix supporting a hard particle structure. At room temperature, the hot melt adhesive is dominated by the soft phase to provide initial tack. Comparative Example A2 did not add heat-resistant naphthenic oil, resulting in a decrease in its initial tack and holding power. At the same time, heat-resistant naphthenic oil has high-temperature properties. Comparative Example A1 did not add heat-resistant naphthenic oil, and its soft phase was only hydrogenated SBC. The addition of naphthenic oil can effectively wet the bonding surface, resulting in lower holding power of Comparative Example A1 than that of Example A.

[0043] 3. Comparison between Example A and Comparative Example A3 shows that Comparative Example A3 uses rosin glycerol ester instead of the hydrogenated petroleum resin in Example A. Rosin glycerol ester is a low-softening-point tackifying resin with a softening point of 80-90℃; while the softening point of hydrogenated petroleum resin ranges from 115-145℃, having a high softening point. As a small molecule compound, the high-softening-point tackifying resin can act as a non-conductive filler, improving the dispersibility of nano-alumina and enabling it to form a more effective network structure, thereby reducing the percolation threshold. When the nano-alumina reaches the percolation threshold, 5-15 parts of nano-alumina can form a three-dimensional continuous thermally conductive network, thereby promoting the function of thermally conductive pathways and providing thermal channels for the hot melt adhesive, further improving the thermal stability of the hot melt adhesive. Therefore, the thermal stability of the hot melt adhesive in Example A is better than that in Comparative Example A3.

[0044] Example B: A process for preparing a hot melt adhesive that combines high initial tack and high heat resistance includes the following steps: Step (1): Heat the reactor to 145°C, add 5 parts of heat-resistant naphthenic oil (Karamay KN4006) and 20 parts of high softening point tackifying resin (hydrogenated petroleum resin, Eastman C-115W), start stirring, so that the high softening point tackifying resin is initially softened in the heat-resistant naphthenic oil.

[0045] Step (2): Slowly add 30 parts of hydrogenated SBC to the reactor, keep the temperature at 155℃, and stir until the hydrogenated SBC is completely melted; add the remaining 20 parts of high softening point tackifying resin (hydrogenated terpene resin, Matsukawa SR125) to the reactor and mix evenly. Step (3): Add nano-alumina (50-70nm) slowly in batches to the reactor, control the temperature at 165℃, apply vacuum (-0.08 MPa), and continue stirring until the nano-alumina is completely dispersed to obtain a uniform and smooth colloid; the mass fraction of nano-alumina is shown in Table 2. Step (4): Cool the reactor to 110°C; add 1.5 parts of antioxidant (phosphite auxiliary antioxidant 168, Rianon) and 1.5 parts of light stabilizer (Tinuvin 326) in sequence, and stir until dispersed; slowly add 0.1 parts of thermally activated crosslinking agent (diisopropylbenzene peroxide, pre-dispersed with a small amount of high softening point tackifying resin), mix evenly and then discharge.

[0046] Table 2 - Amount of nano-alumina added in Example B

[0047] Performance tests were conducted on Example B and Comparative Examples B1-B3, and the results are shown in Table 3. Table 3 - Performance Tests for Example B

[0048] illustrate: 1. As can be seen from the comparison between Example B1 and Comparative Example A1, Example B1 added 3 parts of nano-alumina compared to Comparative Example A1, and the thermal stability of Example B1 was improved, which shows that adding nano-alumina can improve the thermal stability of hot melt adhesive.

[0049] 2. Comparing Examples B2-B4 with Example B1, it can be seen that Example B2 contains 2 more parts of nano-alumina than Example B1, which can effectively improve the tack of the hot melt adhesive, increasing it from 25h in Example B1 to 30h. The optimal tack is achieved with 10 parts of nano-alumina in Example B3. Further increasing the amount of nano-alumina to 17 parts in Example B5 reduces the tack to 25h, which is lower than the 30h tack of Example B4. This is because when the amount of nano-alumina exceeds 15 parts, the relative amount of polymer matrix encapsulating it is too small, resulting in poor continuity of the overall adhesive layer. There is a performance difference at the interface between the rigid nano-alumina and the relatively soft polymer matrix, and the filler disrupts the "adhesion-cohesion balance" necessary for the adhesive to achieve durable bonding. This indicates that the best effect on improving the tack of the hot melt adhesive is achieved when the amount of nano-alumina added is between 5 and 15 parts.

[0050] Example C: A process for preparing a hot melt adhesive that combines high initial tack and high heat resistance includes the following steps: Step (1): Heat the reactor to 140°C, add 15 parts of heat-resistant naphthenic oil (Karamay KN4006) and 20 parts of high softening point tackifying resin (hydrogenated terpene resin, Matsukawa SR135), start stirring, and allow the high softening point tackifying resin to soften initially in the heat-resistant naphthenic oil.

[0051] Step (2): Slowly add 30 parts of hydrogenated SBC to the reactor, keep the temperature at 150℃, and stir until the hydrogenated SBC is completely melted; add the remaining 20 parts of high softening point tackifying resin (hydrogenated petroleum resin, Eastman C-100W) to the reactor and mix evenly. Step (3): Add 5 parts of nano alumina (10-40nm) slowly in batches to the reactor, control the temperature at 160℃, draw a vacuum (-0.07 MPa), and continue stirring until the nano alumina is completely dispersed to obtain a uniform and smooth colloid. Step (4): Cool the reactor to 100℃; add 0.5 parts of antioxidant (phosphite auxiliary antioxidant 168, Rianon) and 0.5 parts of light stabilizer (Tinuvin 326 and Tinuvin 770 in a 1:1 ratio) in sequence, and stir until dispersed; slowly add 0.3 parts of thermally activated crosslinking agent (diisopropylbenzene peroxide, pre-dispersed with a small amount of high softening point tackifying resin), mix evenly and then discharge.

[0052] Example D: A process for preparing a hot melt adhesive that combines high initial tack and high heat resistance includes the following steps: Step (1): Heat the reactor to 110°C, add 15 parts of heat-resistant naphthenic oil (Karamay KN4006) and 20 parts of high softening point tackifying resin (hydrogenated terpene resin, Matsukawa SR125), start stirring, so that the high softening point tackifying resin is initially softened in the heat-resistant naphthenic oil.

[0053] Step (2): Slowly add 30 parts of hydrogenated SBC to the reactor, keep the temperature at 120℃, and stir until the hydrogenated SBC is completely melted; add the remaining 20 parts of high softening point tackifying resin (hydrogenated terpene resin, Matsukawa SR125) to the reactor and mix evenly. Step (3): Add 5 parts of nano alumina (10-40nm) slowly in batches to the reactor, control the temperature at 130℃, draw a vacuum (-0.07 MPa), and continue stirring until the nano alumina is completely dispersed to obtain a uniform and smooth adhesive. Step (4): Cool the reactor to 100℃; add 0.5 parts of antioxidant (phosphite auxiliary antioxidant 168, Rianon) and 0.5 parts of light stabilizer (Tinuvin 326 and Tinuvin 770 in a 1:1 ratio) in sequence, and stir until dispersed; slowly add 0.3 parts of thermally activated crosslinking agent (diisopropylbenzene peroxide, pre-dispersed with a small amount of high softening point tackifying resin), mix evenly and then discharge.

[0054] Performance tests were conducted on Examples C and D, and the results are shown in Table 4. Table 4 - Performance Tests of Examples C and D

[0055] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A hot melt adhesive that combines high initial tack and high heat resistance, characterized in that, The raw materials, by weight, include: 30-50 parts hydrogenated SBC, 40-60 parts high softening point tackifying resin, 5-15 parts heat-resistant naphthenic oil, 5-15 parts nano alumina, 0.1-0.5 parts thermally activated crosslinking agent, 0.5-1.5 parts antioxidant, and 0.5-1.5 parts light stabilizer; The softening point of the high softening point tackifying resin is 90–150°C.

2. The hot melt adhesive with both high initial tack and high heat resistance according to claim 1, characterized in that, The high softening point tackifying resin is a hydrogenated petroleum resin and / or a hydrogenated terpene resin.

3. The hot melt adhesive with both high initial tack and high heat resistance according to claim 1, characterized in that, The particle size of the nano-alumina is 10–100 nm.

4. The hot melt adhesive with both high initial tack and high heat resistance according to claim 1, characterized in that, The thermally activated crosslinking agent is dicumyl peroxide.

5. A process for preparing a hot melt adhesive possessing both high initial tack and high heat resistance, used to prepare the hot melt adhesive possessing both high initial tack and high heat resistance as described in any one of claims 1-4, characterized in that, Includes the following steps: Step (1): Place the heat-resistant naphthenic oil and a portion of the high softening point thickening resin in the reaction vessel and stir to allow the high softening point thickening resin to soften initially in the heat-resistant naphthenic oil. Step (2): Slowly add hydrogenated SBC to the reactor and stir until the hydrogenated SBC is completely melted; add the remaining high softening point thickening resin to the reactor and mix evenly. Step (3): Add the nano-alumina slowly in batches to the reactor and stir continuously until the nano-alumina is completely dispersed; Step (4): Cool the reactor to a temperature below the initial decomposition temperature of the thermally activated crosslinking agent; add antioxidant and light stabilizer in sequence and stir until dispersed; slowly add the thermally activated crosslinking agent, mix evenly and then discharge.

6. The process for preparing a hot melt adhesive with both high initial tack and high heat resistance according to claim 5, characterized in that, In step (3), the reactor is evacuated when nano-alumina is added.

7. A back panel for a household appliance, characterized in that, Use the hot melt adhesive that combines high initial tack and high heat resistance as described in any one of claims 1-4.

8. The use of a hot melt adhesive in a television back panel, characterized in that, The hot melt adhesive is a hot melt adhesive with both high initial tack and high heat resistance as described in any one of claims 1-4.

Images