Hot melt adhesive for car lamp as well as preparation method and application of hot melt adhesive

Abstract

The invention relates to a hot melt adhesive for a car lamp and a preparation method and application thereof, and the hot melt adhesive for the car lamp is prepared from the following raw materials in parts by weight: 15-40 parts of polyisobutene, 20-60 parts of amorphous polyolefin, 5-15 parts of organic silicon modified polyolefin, 0.1-1 part of antioxidant, 3-30 parts of porous filler and 1-20 parts of carbon black. The organic silicon modified polyolefin comprises silane coupling agent modified polyolefin. According to the hot melt adhesive for the vehicle lamp provided by the invention, the prepared raw materials are screened, so that the obtained hot melt adhesive for the vehicle lamp has an extremely low volatile value, the volatile component is less than 0.35, and the problems of corrosion and optical pollution of internal components of the vehicle lamp caused by volatilization of small organic molecules from a traditional hot melt adhesive are effectively avoided. Meanwhile, the hot melt adhesive for the vehicle lamp has good compatibility with an anti-fog coating, has small influence on the anti-fog coating, has the anti-fog grade as high as 4-5, and can effectively protect the structural integrity of the coating and ensure that the lighting efficiency of the vehicle lamp is stable.

Description

Technical Field

[0001] The invention belongs to the technical field of hot melt adhesives, and in particular relates to a hot melt adhesive for vehicle lamps and a preparation method and application thereof. Background Art

[0002] In the field of automotive lighting manufacturing, the bonding and sealing of headlights are extremely critical links. As an important guarantee for automobile driving safety, the quality of the bonding of headlights is directly related to the performance of headlights in various complex and harsh environments. Ideal headlight bonding should ensure that under adverse conditions such as extreme temperature, humidity, vibration, etc., the headlights will not have problems such as debonding due to stress, water and oil seepage, discoloration and fogging, so as to maintain a stable and reliable lighting effect.

[0003] In the traditional bonding process of headlights, hot melt adhesive has become the main choice of adhesive due to its advantages such as fast curing speed, good initial adhesion and detachability. However, traditional hot melt adhesives are mostly composed of polyisobutylene and terpene phenol, which leads to a high content of volatile matter in high temperature environments. The large amount of volatile matter released will not only have a significant impact on the anti-fog coating of the headlights, but also destroy the stability and effectiveness of the anti-fog coating, and ultimately cause serious interference with the field of vision of the headlights, affecting the driver's line of sight and posing potential risks to driving safety.

[0004] With the rapid development of the automotive industry and the increasing requirements of consumers for driving safety and lighting quality, the development of a new type of hot melt adhesive with low volatility and little impact on the anti-fog coating of car lights has become a key issue that needs to be urgently solved in the field of car light bonding applications. This will not only help improve the overall performance and reliability of car lights, but also further promote the advancement of automotive lighting manufacturing technology and meet the growing market demand. Summary of the invention

[0005] In view of the deficiencies in the prior art, the object of the present invention is to provide a hot melt adhesive for vehicle lamps and a preparation method and application thereof.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a hot melt adhesive for a vehicle lamp. The raw materials for preparing the hot melt adhesive for a vehicle lamp include, by weight:

[0008]

[0009] The organosilicon-modified polyolefin includes a silane coupling agent-modified polyolefin.

[0010] The hot melt adhesive for car lights provided by the present invention has an extremely low volatility value through screening of the raw materials, with a volatility of <0.35, which effectively avoids the corrosion of the internal components of the car lights and the optical pollution caused by the volatilization of small organic molecules by the traditional hot melt adhesive. At the same time, the hot melt adhesive for car lights provided by the present invention has good compatibility with the anti-fog coating, has little effect on the anti-fog coating, and has an anti-fog grade of up to 4-5, which can effectively protect the integrity of the coating structure and ensure the stability of the lighting efficiency of the car lights.

[0011] The weight proportions of the polyisobutylene may be 15 parts, 17 parts, 19 parts, 20 parts, 22 parts, 24 parts, 26 parts, 28 parts, 30 parts, 32 parts, 35 parts, 37 parts, 40 parts, etc.

[0012] The weight proportions of the amorphous polyolefin may be 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, 60 parts, etc.

[0013] The weight proportions of the organosilicon-modified polyolefin may be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, etc.

[0014] The weight proportion of the antioxidant can be 0.1 part, 0.2 part, 0.3 part, 0.4 part, 0.5 part, 0.6 part, 0.7 part, 0.8 part, 0.9 part, 1 part, etc.

[0015] The weight proportions of the porous filler may be 3 parts, 5 parts, 7 parts, 10 parts, 12 parts, 14 parts, 16 parts, 18 parts, 20 parts, 23 parts, 25 parts, 27 parts, 30 parts, etc.

[0016] The weight proportions of the carbon black can be 1 part, 3 parts, 5 parts, 7 parts, 9 parts, 11 parts, 13 parts, 15 parts, 17 parts, 19 parts, 20 parts, etc.

[0017] Other specific point values ​​within the above numerical ranges can be selected and will not be described in detail here.

[0018] Preferably, the viscosity average molecular weight of the polyisobutylene is 200000-4000000 (e.g., 200000, 300000, 500000, 700000, 1000000, 1500000, 2000000, 2500000, 3000000, 3500000, 4000000, etc.), and the Staudinger index is 70-700cm 3 / g (e.g. 70cm 3 / g, 80cm 3 / g, 90cm 3 / g、100cm 3 / g、200cm3 / g、300cm 3 / g、400cm 3 / g、500cm 3 / g、600cm 3 / g、700cm 3 / g, etc.), other specific point values ​​within the above numerical ranges can be selected, and will not be described in detail here.

[0019] In the present invention, the polyisobutylene can be purchased, for example, it can be purchased from BASF as Oppanol B50, Oppanol B80, Oppanol B100, Oppanol B150, and Oppanol B200.

[0020] Preferably, the amorphous polyolefin comprises an alpha-olefin polymer.

[0021] Preferably, the α-olefin includes any one of ethylene, propylene, 1-butene, isobutylene, 1-pentene, 1-hexene, 1-octene or 4-methyl-1-pentene, or a combination of at least two thereof.

[0022] Preferably, the softening point of the amorphous polyolefin is 80-120°C (for example, 80°C, 85°C, 90°C, 95°C, 100°C, 110°C, 120°C, etc.), and the melt viscosity at 190°C is 2000-20000mPa·s (for example, 2000mPa·s, 4000mPa·s, 6000mPa·s, 8000mPa·s, 10000mPa·s, 12000mPa·s, 14000mPa·s, 16000mPa·s, 18000mPa·s, 20000mPa·s, etc.), and other specific point values ​​within the above numerical ranges can be selected, which will not be described one by one here.

[0023] In the present invention, the amorphous polyolefin can be purchased, for example, it can be purchased from Evonik as Vestoplast 508, Vestoplast 704, or Vestoplast 708.

[0024] Preferably, the organosilicon-modified polyolefin includes any one of silane coupling agent-modified polyisobutylene, silane coupling agent-modified amorphous α-polyolefin, or silane coupling agent-modified metallocene-catalyzed vinyl copolymer, or a combination of at least two thereof.

[0025] In the present invention, the silane coupling agent modified polyisobutylene can be purchased, for example, it can be purchased from the EPION series of Kaneka Chemical; the silane coupling agent modified amorphous α-polyolefin can be purchased, for example, it can be purchased from VESTOPLAST 206 of Evonik; the silane coupling agent modified metallocene-catalyzed vinyl copolymer can be purchased, for example, it can be purchased from the Si-link series of Dow Chemical.

[0026] Preferably, the antioxidant includes a primary antioxidant and a secondary antioxidant.

[0027] Preferably, the primary antioxidant comprises an aromatic amine antioxidant and / or a hindered phenol antioxidant.

[0028] Preferably, the aromatic antioxidant includes any one of diaryl secondary amines, p-phenylenediamine, ketoamines or aldehyde amines, or a combination of at least two thereof.

[0029] Preferably, the hindered phenol antioxidant includes any one of 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate or n-octadecylβ-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate or a combination of at least two thereof.

[0030] Preferably, the auxiliary antioxidant includes a thioester auxiliary antioxidant and / or a phosphite auxiliary antioxidant.

[0031] Preferably, the thioester auxiliary antioxidant includes distearyl thiodipropionate and / or didodecyl thiodipropionate.

[0032] Preferably, the phosphite auxiliary antioxidant includes tris(2,4-di-tert-butylphenyl) phosphite and / or bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite.

[0033] Preferably, the porous filler comprises a modified molecular sieve.

[0034] Preferably, the pore size of the molecular sieve is 0.6-1.0 nm, for example, 0.6 nm, 0.65 nm, 0.7 nm, 0.75 nm, 0.8 nm, 0.85 nm, 0.9 nm, 0.95 nm, 1.0 nm, etc. Other specific point values ​​within this numerical range can be selected and will not be described here one by one.

[0035] Preferably, the molecular sieve comprises X-type molecular sieve and / or Y-type molecular sieve.

[0036] Preferably, the modifier for modifying the molecular sieve comprises an alkali metal solution.

[0037] Preferably, the alkali metal solution comprises sodium hydroxide solution and / or potassium hydroxide solution.

[0038] Preferably, the modified molecular sieve is prepared by the following method:

[0039] The molecular sieve is mixed with 0.2-1mol / L (e.g., 0.2mol / L, 0.3mol / L, 0.4mol / L, 0.5mol / L, 0.6mol / L, 0.7mol / L, 0.8mol / L, 0.9mol / L, 1mol / L, etc.) of an alkali metal solution, heated to 80-100°C (e.g., 80°C, 82°C, 84°C, 86°C, 88°C, 90°C, 92°C, 94°C, 96°C, 98°C, 100°C, etc.), stirred for 1-3h (e.g., 1h, 1.2h, 1.4h, 1.6h, 1.8h, 2h, 2.2h, 2.4h, 2.6h, 2.8h, 3h, etc.), then filtered, washed and dried to obtain a modified molecular sieve. Other specific point values ​​within the above numerical range can be selected, and they will not be repeated here.

[0040] Preferably, the specific surface area of ​​the carbon black is greater than 100 m 2 / g (e.g. 110m 2 / g, 115m 2 / g, 120m 2 / g, 125m 2 / g, 130m 2 / g, 135m 2 / g, 140m 2 / g, 145m 2 / g, 150m 2 / g, 250m 2 / g, 350m 2 / g, etc.), volatile matter ≤1% (for example, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, 0.1%, etc.), other specific point values ​​within the above numerical ranges can be selected, which will not be described one by one here.

[0041] In the present invention, the carbon black can be purchased, for example, it can be purchased from Orion PRINTEX L (specific surface area 150m 2 / g, volatile matter 0.8%), PRINTEX 95 (specific surface area 250m 2 / g, volatile matter 1.0%), HIBLACK 30 (specific surface area 110m 2 / g, volatile matter 1.0%), PRINTEX 90 (specific surface area 350m2 / g, volatile matter 1.0%), PRINTEX HV (specific surface area 125m 2 / g, volatile matter 0.7%).

[0042] In a second aspect, the present invention provides a method for preparing the hot melt adhesive for vehicle lamps according to the first aspect, the preparation method comprising the following steps:

[0043] The polyisobutylene, amorphous polyolefin and antioxidant are blended, then mixed with porous filler and carbon black, and finally kneaded with organosilicon-modified polyolefin to obtain the hot melt adhesive for vehicle lamps.

[0044] Preferably, the preparation method is carried out at 120-160°C (for example, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C, 155°C, 160°C, etc.), and other specific point values ​​within this numerical range can be selected, which will not be described one by one here.

[0045] Preferably, the blending time is 30-130 min, for example, 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min, 120 min, 130 min, etc. Other specific point values ​​within the numerical range can be selected and will not be described here one by one.

[0046] Preferably, the mixing time is 60-180 min, for example, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min, 120 min, 130 min, 140 min, 150 min, 160 min, 170 min, 180 min, etc. Other specific point values ​​within the numerical range can be selected, which will not be described here one by one.

[0047] Preferably, the kneading time is 30-90 min, for example, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, 65 min, 70 min, 75 min, 80 min, 85 min, 90 min. Other specific point values ​​within this numerical range can be selected and will not be described here one by one.

[0048] Preferably, the method for preparing the hot melt adhesive for vehicle lamps comprises the following steps:

[0049] At 120-160°C, add polyisobutylene, amorphous polyolefin and antioxidant into a kneader, and blend for 30-130 minutes under vacuum protection; then add modified molecular sieve and carbon black, and fully mix for 60-180 minutes under vacuum protection; finally add silicone modified polyolefin, and fully knead for 30-90 minutes under vacuum protection to obtain hot melt adhesive for car lights.

[0050] In a third aspect, the present invention provides a use of the hot melt adhesive for vehicle lamps as described in the first aspect in bonding vehicle lamps.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] The hot melt adhesive for car lights provided by the present invention has a very low volatility value and a volatility of <0.35 by screening the raw materials for preparation, which effectively avoids the corrosion of the internal components of the car lights and the optical pollution caused by the volatilization of small organic molecules by the traditional hot melt adhesive. At the same time, the hot melt adhesive for car lights provided by the present invention has good compatibility with the anti-fog coating, has little effect on the anti-fog coating, and has an anti-fog grade of up to 4-5, which can effectively protect the integrity of the coating structure and ensure the stability of the lighting efficiency of the car lights. DETAILED DESCRIPTION

[0053] In order to further explain the technical means and effects adopted by the present invention, the technical solution of the present invention is further described below in conjunction with the preferred embodiments of the present invention, but the present invention is not limited to the scope of the embodiments.

[0054] In the following examples, unless otherwise specified, the reagents and consumables used were purchased from conventional reagent manufacturers in the field; unless otherwise specified, the experimental methods and technical means used were conventional methods and means in the field.

[0055] Example 1

[0056] This embodiment provides a hot melt adhesive for vehicle lamps, and the preparation method is as follows:

[0057] (1) Preparation of modified molecular sieve: 100 g of X-type molecular sieve (Jianlong Micronano, 13X original powder) was mixed with 1000 g of 0.5 mol / L sodium hydroxide solution, heated to 90° C., stirred for 2 h, and then filtered, washed, and dried to obtain the modified molecular sieve.

[0058] (2) Preparation of hot melt adhesive: At 140°C, polyisobutylene, amorphous polyolefin, and antioxidant were added to a kneader in sequence and mixed under vacuum protection for 60 minutes; then modified molecular sieve and carbon black were added in sequence and fully kneaded under vacuum protection for 60 minutes; finally, silicone-modified polyolefin was added and fully kneaded under vacuum protection for 45 minutes to obtain hot melt adhesive for vehicle lamps. The amount of each raw material is shown in the following table.

[0059]

[0060]

[0061] Example 2

[0062] This embodiment provides a hot melt adhesive for vehicle lamps, and the preparation method is as follows:

[0063] (1) Preparation of modified molecular sieve: 100 g of Y-type molecular sieve (Jianlong Micronano, NaY molecular sieve) was mixed with 1000 g of 0.5 mol / L sodium hydroxide solution, heated to 90° C., stirred for 2 h, and then filtered, washed, and dried to obtain the modified molecular sieve.

[0064] (2) Preparation of hot melt adhesive: At 135°C, polyisobutylene, amorphous polyolefin, and antioxidant were added to a kneader in sequence and mixed under vacuum protection for 70 minutes; then modified molecular sieve and carbon black were added in sequence and fully kneaded under vacuum protection for 70 minutes; finally, silicone-modified polyolefin was added and fully kneaded under vacuum protection for 50 minutes to obtain hot melt adhesive for vehicle lamps. The amount of each raw material is shown in the following table.

[0065]

[0066]

[0067] Example 3

[0068] This embodiment provides a hot melt adhesive for vehicle lamps, and the preparation method is as follows:

[0069] (1) Preparation of modified molecular sieve: 100 g of X-type molecular sieve (Jianlong Micronano, 13X original powder) was mixed with 1000 g of 0.5 mol / L sodium hydroxide solution, heated to 90° C., stirred for 2 h, and then filtered, washed, and dried to obtain the modified molecular sieve.

[0070] (2) Preparation of hot melt adhesive: At 140°C, polyisobutylene, amorphous polyolefin, and antioxidant were added to a kneader in sequence and mixed under vacuum protection for 45 minutes; then modified molecular sieve and carbon black were added in sequence and fully kneaded under vacuum protection for 60 minutes; finally, silicone-modified polyolefin was added and fully kneaded under vacuum protection for 70 minutes to obtain hot melt adhesive for vehicle lamps. The amount of each raw material is shown in the following table.

[0071] raw material Input amount / g Polyisobutylene Oppanol B100 35 Amorphous polyolefin Vestoplast 704 45 Silicone modified polyolefin Vestoplast 206 10 Primary Antioxidant RIANOX 1076 0.1 Auxiliary antioxidant RIANOX 168 0.1 Modified molecular sieve 7 Carbon Black PRINTEX HV 4

[0072] Example 4

[0073] This embodiment provides a hot melt adhesive for vehicle lamps, and the preparation method is as follows:

[0074] (1) Preparation of modified molecular sieve: 100 g of X-type molecular sieve (Jianlong Micronano, 13X original powder) was mixed with 1000 g of 0.5 mol / L sodium hydroxide solution, heated to 90° C., stirred for 2 h, and then filtered, washed, and dried to obtain the modified molecular sieve.

[0075] (2) Preparation of hot melt adhesive: At 140°C, polyisobutylene, amorphous polyolefin, and antioxidant were added to a kneader in sequence and mixed under vacuum protection for 45 minutes; then modified molecular sieve and carbon black were added in sequence and fully kneaded under vacuum protection for 60 minutes; finally, silicone-modified polyolefin was added and fully kneaded under vacuum protection for 70 minutes to obtain hot melt adhesive for vehicle lamps. The amount of each raw material is shown in the following table.

[0076] raw material Input amount / g Polyisobutylene Oppanol B150 25 Amorphous polyolefin Vestoplast 704 45 Silicone modified polyolefin Vestoplast 206 10 Primary Antioxidant RIANOX 1010 0.1 Auxiliary antioxidant RIANOX 168 0.1 Modified molecular sieve 9 Carbon Black PRINTEX HV 3

[0077] Example 5

[0078] This embodiment provides a hot melt adhesive for vehicle lamps, and the preparation method is as follows:

[0079] (1) Preparation of modified molecular sieve: 100 g of X-type molecular sieve (Jianlong Micronano, 13X original powder) was mixed with 1000 g of 0.4 mol / L sodium hydroxide solution, heated to 95° C., stirred for 2 h, and then filtered, washed, and dried to obtain the modified molecular sieve.

[0080] (2) Preparation of hot melt adhesive: At 135° C., polyisobutylene, amorphous polyolefin, and antioxidant were added to a kneader in sequence and blended under vacuum protection for 100 min. Then, modified molecular sieve and carbon black were added in sequence and fully kneaded under vacuum protection for 80 min. Finally, silicone-modified polyolefin was added and fully kneaded under vacuum protection for 40 min to obtain a hot melt adhesive for car lights.

[0081] raw material Input amount / g Polyisobutylene Oppanol B50 35 Amorphous polyolefin Vestoplast 708 45 Silicone modified polyolefin Vestoplast 206 10 Primary Antioxidant RIANOX 1010 0.1 Auxiliary antioxidant RIANOX DSTP 0.1 Modified molecular sieve 10 Carbon Black PRINTEX HV 5

[0082] Example 6

[0083] This embodiment provides a hot melt adhesive for vehicle lamps, which differs from Embodiment 1 only in that the polyisobutylene Oppanol B50 is replaced with polyisobutylene HRD-24 (Shandong Hongrui New Materials, molecular weight 2400), and other conditions remain unchanged.

[0084] Example 7

[0085] This embodiment provides a hot melt adhesive for vehicle lamps, which differs from Embodiment 1 only in that the modified molecular sieve is replaced with X molecular sieve (Jianlong Micro-Nano, 13X original powder), and other conditions remain unchanged.

[0086] Example 8

[0087] This embodiment provides a hot melt adhesive for vehicle lamps, which differs from Embodiment 1 only in that the modified molecular sieve is replaced with calcium carbonate, and other conditions remain unchanged.

[0088] Comparative Example 1

[0089] This comparative example provides a hot melt adhesive for vehicle lamps, which differs from Example 1 only in that the organosilicon-modified polyolefin Vestoplast 206 is replaced with terpene phenol resin, and other conditions remain unchanged.

[0090] Comparative Example 2

[0091] This comparative example provides a hot melt adhesive for vehicle lamps, which differs from Example 1 only in that the organosilicon-modified polyolefin Vestoplast 206 is replaced with C5 petroleum resin H5-1000, and other conditions remain unchanged.

[0092] Comparative Example 3

[0093] This comparative example provides a hot melt adhesive for vehicle lamps, which differs from Example 1 only in that the amorphous polyolefin Vestoplast 508 is replaced with C5 petroleum resin H5-1000, and other conditions remain unchanged.

[0094] Test Example 1

[0095] This test example tests the performance of the hot melt adhesives for vehicle lamps prepared in Examples 1-8 and Comparative Examples 1-3, and the test method is as follows:

[0096] Melt viscosity measurement: according to HG / T3660-1999 Determination of melt viscosity of hot melt adhesives, room temperature 190°C.

[0097] Volatile matter measurement: According to GB / T 2793-1995 Determination of non-volatile matter content of adhesives, the experimental temperature is 105±2℃, and a sample of 1.0g hot melt adhesive is cured in an oven for 180±5min, then placed in a desiccator and cooled to room temperature. The weight is weighed and the weight loss is calculated. The weight loss percentage is the volatile matter content percentage.

[0098] Evaluation of anti-fog coating: 10 g of sample was placed in a beaker, and then a lid with a 40 mm round hole was placed on the beaker, and then an anti-fog coating sheet was placed on the round hole; the beaker was placed in a 100 °C oil bath and heated for 24 h; finally, the anti-fog coating sheet was removed, and after being placed at room temperature for 30 min, the appearance was evaluated according to Table 1.

[0099] The results are shown in Table 2.

[0100] Table 1

[0101]

[0102]

[0103] Table 2

[0104] Group Melt viscosity Pa·s Volatile matter% Anti-fog level Example 1 11.5 0.31 5 Example 2 10.8 0.29 5 Example 3 13.1 0.34 4 Example 4 14.2 0.24 5 Example 5 11.2 0.28 5 Example 6 1.8 2.11 2 Example 7 13.3 0.54 3 Example 8 15.4 0.58 2 Comparative Example 1 6.7 1.13 2 Comparative Example 2 5.8 0.96 2 Comparative Example 3 2.1 1.49 1

[0105] From the data in Table 2, it can be seen that the hot melt adhesive for car lights prepared in Examples 1-5 has a melt viscosity of 10.8-14.2 Pa·s, a volatile matter of only 0.24%-0.34%, and an anti-fog grade of up to 4-5. The above data indicate that the hot melt adhesive for car lights prepared in Examples 1-5 has a low volatility value, has little effect on the anti-fog coating, and can be used for bonding and sealing of car lights.

[0106] By comparing Example 1 with Example 6, it can be seen that the molecular weight of polyisobutylene will have a significant effect on the melt viscosity, volatility and anti-fog level of the hot melt adhesive. When the molecular weight of polyisobutylene is too low, the melt viscosity and anti-fog level of the prepared hot melt adhesive decrease significantly, and the volatile matter increases significantly.

[0107] By comparing Example 1 with Examples 7-8, it can be seen that the use of modified molecular sieve as the porous filler phase can effectively reduce the volatile matter of the hot melt adhesive and reduce the impact on the anti-fog coating.

[0108] By comparing Example 1 with Comparative Examples 1-2, it can be seen that the use of silicone-modified polyolefin as a tackifying resin can effectively increase the melt viscosity of the hot melt adhesive, reduce volatile matter, and reduce the impact of the hot melt adhesive on the anti-fog coating compared to common terpene phenol resins and C5 resins.

[0109] By comparing Example 1 with Comparative Example 3, it can be seen that when the amorphous polyolefin is replaced with C5 resin, the melt viscosity and anti-fog grade of the prepared hot melt adhesive are significantly reduced, and the volatile matter is significantly increased.

[0110] The applicant declares that the present invention illustrates the technical solution of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0111] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0112] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. A hot melt adhesive for vehicle lamps, characterized in that: The raw materials for preparing the hot melt adhesive for vehicle lamps include, by weight: The organosilicon-modified polyolefin includes a silane coupling agent-modified polyolefin.

2. The hot melt adhesive for vehicle lamps according to claim 1, characterized in that: The viscosity average molecular weight of the polyisobutylene is 200,000-4,000,000, and the Staudinger index is 70-700 cm 3 / g.

3. The hot melt adhesive for vehicle lamps according to claim 1 or 2, characterized in that: The amorphous polyolefin comprises an alpha-olefin polymer; Preferably, the α-olefin includes any one or a combination of at least two of ethylene, propylene, 1-butene, isobutylene, 1-pentene, 1-hexene, 1-octene or 4-methyl-1-pentene; Preferably, the amorphous polyolefin has a softening point of 80-120° C. and a melt viscosity of 2000-20000 mPa·s at 190° C.

4. The hot melt adhesive for vehicle lamps according to any one of claims 1 to 3, characterized in that: The organosilicon-modified polyolefin includes any one of silane coupling agent-modified polyisobutylene, silane coupling agent-modified amorphous alpha polyolefin, and silane coupling agent-modified metallocene-catalyzed vinyl copolymer, or a combination of at least two thereof.

5. The hot melt adhesive for vehicle lamps according to any one of claims 1 to 4, characterized in that: The antioxidants include primary antioxidants and auxiliary antioxidants; Preferably, the primary antioxidant comprises an aromatic amine antioxidant and / or a hindered phenol antioxidant; Preferably, the aromatic antioxidant includes any one or a combination of at least two of diaryl secondary amines, p-phenylenediamine, ketoamines or aldehyde amines; Preferably, the hindered phenol antioxidant includes any one of 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate or n-octadecylβ-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate or a combination of at least two thereof; Preferably, the auxiliary antioxidant includes a thioester auxiliary antioxidant and / or a phosphite auxiliary antioxidant; Preferably, the thioester auxiliary antioxidant includes distearyl thiodipropionate and / or didodecyl thiodipropionate; Preferably, the phosphite auxiliary antioxidant includes tris(2,4-di-tert-butylphenyl) phosphite and / or bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite.

6. The hot melt adhesive for vehicle lamps according to any one of claims 1 to 5, characterized in that: The porous filler comprises a modified molecular sieve; Preferably, the pore size of the molecular sieve is 0.6-1.0 nm; Preferably, the molecular sieve comprises an X-type molecular sieve and / or a Y-type molecular sieve; Preferably, the modifier of the modified molecular sieve comprises an alkali metal solution; Preferably, the alkali metal solution comprises sodium hydroxide solution and / or potassium hydroxide solution.

7. The hot melt adhesive for vehicle lamps according to any one of claims 1 to 6, characterized in that: The specific surface area of ​​the carbon black is > 100 m 2 / g, volatile matter ≤1%.

8. A method for preparing the hot melt adhesive for vehicle lamps according to any one of claims 1 to 7, characterized in that: The preparation method comprises the following steps: The polyisobutylene, amorphous polyolefin and antioxidant are blended, then mixed with porous filler and carbon black, and finally kneaded with organosilicon-modified polyolefin to obtain the hot melt adhesive for vehicle lamps.

9. The method for preparing hot melt adhesive for vehicle lamps according to claim 8, characterized in that: The preparation method is carried out at 120-160°C; Preferably, the blending time is 30-130 min; Preferably, the mixing time is 60-180 min; Preferably, the kneading time is 30-90 min.

10. Use of the hot melt adhesive for vehicle lamps as claimed in any one of claims 1 to 7 in bonding vehicle lamps.

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