A kind of hot-melt pressure-sensitive adhesive for heat-resistant high-viscosity woven cloth tape and preparation method thereof

Abstract

The present application relates to the field of adhesives, and specifically discloses a heat-resistant and highly viscous hot melt pressure-sensitive adhesive for woven cloth tape and a preparation method thereof. A heat-resistant and highly viscous hot melt pressure-sensitive adhesive for woven cloth tape, comprising the following raw materials in parts by weight: 20-35 parts of a main polymer, 40-50 parts of a tackifying resin, 15-30 parts of a medium molecular weight polyisobutylene, and 0.3-1 parts of an antioxidant, wherein the main polymer is a mixture of styrene-ethylene-butylene-styrene block copolymers and styrene-butadiene-styrene triblock copolymers, the tackifying resin is a mixture of C5 petroleum resin and maple resin, and the medium molecular weight polyisobutylene has a number average molecular weight of 35000-45000. The present application discloses a heat-resistant and highly viscous hot melt pressure-sensitive adhesive for woven cloth tape, using medium molecular weight polyisobutylene instead of the traditional diluent naphthenic oil, thereby improving the initial viscosity and cohesion of the hot melt pressure-sensitive adhesive, and promoting the hot melt pressure-sensitive adhesive to have excellent holding force, peel strength and high temperature resistance.

Description

Technical Field

[0001] The present application relates to the field of adhesives, and more specifically, to a hot-melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven cloth tape and a preparation method thereof. Background Art

[0002] Hot melt pressure sensitive adhesive is a new type of adhesive that does not contain any solvents. It has the advantages of being pollution-free, green and environmentally friendly, simple production process, low cost, low equipment investment, ease of use, and high production efficiency. It is widely used in various fields.

[0003] Hot melt pressure sensitive adhesive for woven fabric tape generally uses naphthenic oil as a diluent. However, the disadvantages of using naphthenic oil are: in summer, the ambient temperature is high. If more naphthenic oil is added to the hot melt pressure sensitive adhesive, the higher ambient temperature will cause the naphthenic oil in the hot melt pressure sensitive adhesive to precipitate, thereby contaminating the adhered object and reducing the adhesion; in winter, due to the low temperature, if less naphthenic oil is added to the hot melt pressure sensitive adhesive, the applied tape and the adhered substrate will not be sufficiently wetted, resulting in a decrease in the bonding effect, and the tape is easy to fall off the substrate.

[0004] There are two methods generally used in the market: one formula in summer, with less naphthenic oil, lower initial viscosity and higher cohesion; another formula in winter, with more naphthenic oil, higher initial viscosity and lower cohesion. However, when the seasons change, it is easy to have problems such as the tape falling off due to insufficient initial adhesion or poor high temperature retention due to insufficient cohesion. Summary of the invention

[0005] In order to improve the influence of cyclohexane oil diluent on the adhesion of hot melt pressure-sensitive adhesive, the present application provides a hot melt pressure-sensitive adhesive for heat-resistant high-viscosity woven cloth tape and a preparation method thereof.

[0006] In the first aspect, the present application provides a hot-melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven fabric tape, which adopts the following technical solution:

[0007] A hot-melt pressure-sensitive adhesive for a heat-resistant high-viscosity woven cloth tape comprises the following raw materials in parts by weight: 20-35 parts of a main polymer, 40-50 parts of a tackifying resin, 15-30 parts of a medium molecular weight polyisobutylene, and 0.3-1 part of an antioxidant. The main polymer is a mixture of styrene-ethylene-butylene-styrene block copolymer and styrene-butadiene-styrene triblock copolymer, the tackifying resin is a mixture of C5 petroleum resin and maple balsam, and the number average molecular weight of the medium molecular weight polyisobutylene is 35000-45000.

[0008] By adopting the above technical scheme, styrene-butadiene-styrene triblock copolymer has excellent tensile strength and resilience, styrene-ethylene-butylene-styrene block copolymer has excellent rigidity and aging resistance, and the hot melt pressure-sensitive adhesive made of styrene-ethylene-butylene-styrene block copolymer and styrene-butadiene-styrene triblock copolymer has excellent bonding performance and cohesion, and high production efficiency. Use medium molecular weight polyisobutylene as diluent to add to the hot melt pressure-sensitive adhesive system, with excellent initial adhesion and cohesion, replace the traditional diluent naphthenic oil, and improve the bonding performance of the hot melt pressure-sensitive adhesive. And the addition of medium molecular weight polyisobutylene to the hot melt pressure-sensitive adhesive system can increase the wettability between the hot melt pressure-sensitive adhesive and the substrate, the cohesive strength of the colloid is large, regardless of winter and summer glue, the weather resistance of the hot melt pressure-sensitive adhesive is improved, and the colloid is also prompted to have certain elasticity and flexibility. Tackifying resin can improve the high temperature adhesion of the hot melt pressure-sensitive adhesive, enhance the bonding force between the hot melt pressure-sensitive adhesive and the substrate, and improve the high temperature resistance of the hot melt machine. By compounding C5 petroleum resin and maple balsam as tackifying resin and adding them to the hot melt pressure-sensitive adhesive system, on the one hand, C5 petroleum resin can improve the cohesive strength of the hot melt pressure-sensitive adhesive, and maple balsam has a lower softening point, which can improve the initial adhesion performance of the hot melt pressure-sensitive adhesive.

[0009] Preferably, the hot melt pressure sensitive adhesive raw material further includes 1-3 parts of acrylonitrile and 0.3-0.5 parts of initiator.

[0010] By adopting the above technical scheme, acrylonitrile can be grafted and copolymerized with the main polymer molecular chain under the action of the initiator, thereby introducing the polar group of acrylonitrile into the hot melt pressure-sensitive adhesive system, improving the flexibility and bonding performance of the hot melt pressure-sensitive adhesive, enhancing the bonding force between the hot melt pressure-sensitive adhesive and the woven fabric substrate, and improving the initial adhesion and peel strength of the hot melt pressure-sensitive adhesive.

[0011] Preferably, the hot melt pressure-sensitive adhesive raw material further comprises 3-5 parts of maleic anhydride and 1-3 parts of polyethylene wax.

[0012] By adopting the above technical solution, maleic anhydride has excellent heat resistance, and maleic anhydride can be grafted onto the molecular chain of the hot melt pressure sensitive adhesive under the action of an initiator, which can improve the heat resistance of the hot melt pressure sensitive adhesive, and the polar group of maleic anhydride is connected to the polymer molecular chain, which can also improve the cohesive strength and bonding performance of the hot melt pressure sensitive adhesive. On the other hand, the double bond of maleic anhydride can also undergo free radical polymerization reaction with the double bond of C5 petroleum resin, thereby improving the viscosity of C5 petroleum resin and the adhesion to the substrate, thereby further improving the bonding strength of the hot melt pressure sensitive adhesive.

[0013] The free radicals of polyethylene wax can attack the molecular chain of maleic anhydride, thus causing a grafting reaction, which promotes the uniform dispersion of maleic anhydride in the hot melt pressure sensitive adhesive system. Polyethylene wax and tackifying resin can adjust the melt viscosity of the hot melt pressure sensitive adhesive, reduce the self-adhesive phenomenon of the hot melt pressure sensitive adhesive, improve the fluidity of the hot melt pressure sensitive adhesive system and the wettability of the hot melt pressure sensitive adhesive and the adhered object, and further improve the initial adhesion and peel strength of the hot melt pressure sensitive adhesive. At the same time, polyethylene wax forms a certain film-forming protection on the surface of the hot melt pressure sensitive adhesive, which makes the hot melt pressure sensitive adhesive have a certain waterproof performance.

[0014] Preferably, the main polymer is a mixture of styrene-ethylene-butylene-styrene block copolymer and styrene-butadiene-styrene triblock copolymer in a mass ratio of (1.5-1):1.

[0015] By adopting the above technical solution, the styrene-ethylene-butylene-styrene block copolymer and the styrene-butadiene-styrene triblock copolymer are compounded and strengthened, so that the hot melt pressure sensitive adhesive has excellent bonding performance, tensile shear strength and aging resistance. At the same time, the styrene-ethylene-butylene-styrene block copolymer can also improve the high temperature resistance of the hot melt pressure sensitive adhesive and the adhesion performance with the substrate, so the amount of styrene-ethylene-butylene-styrene block copolymer used in the polymer is slightly more.

[0016] Preferably, the tackifying resin is a mixture of C5 petroleum resin and maple balsam in a mass ratio of 1:(0.8-0.5).

[0017] By adopting the above technical scheme, the bonding strength of the hot melt pressure-sensitive adhesive is improved by compounding C5 petroleum resin and maple resin. Controlling the appropriate amount of maple resin can improve the initial adhesion and peel strength of the hot melt pressure-sensitive adhesive, but too much maple resin will affect the holding force of the hot melt pressure-sensitive adhesive.

[0018] Preferably, the hot melt pressure-sensitive adhesive raw material further comprises 0.5-1 part of 2-hydroxy-4-n-octyloxybenzophenone.

[0019] By adopting the above technical scheme, 2-hydroxy-4-n-octyloxybenzophenone has excellent ultraviolet absorption performance. Adding 2-hydroxy-4-n-octyloxybenzophenone to the hot melt pressure-sensitive adhesive system can reduce the carbonyl index on the surface of the hot melt pressure-sensitive adhesive, thereby inhibiting the ultraviolet light aging effect, extending the service life of the hot melt pressure-sensitive adhesive, improving the mechanical properties of the hot melt pressure-sensitive adhesive, and promoting the hot melt pressure-sensitive adhesive and the substrate to have excellent bonding strength.

[0020] In a second aspect, the present application provides a method for preparing a hot-melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven cloth tape, using the following technical solution:

[0021] A method for preparing a hot melt pressure-sensitive adhesive for a heat-resistant high-viscosity woven cloth tape comprises the following specific steps: firstly, a main polymer, an antioxidant and a medium molecular weight polyisobutylene are mixed, the temperature is raised to 140-150° C., and heated for 30-40 minutes to obtain a molten mixture, and then the molten mixture is mixed and stirred with a tackifying resin to form a hot melt pressure-sensitive adhesive mixture;

[0022] Finally, the hot-melt pressure-sensitive adhesive mixture is filtered, coated on the surface of the release paper, and packaged after cooling to obtain the hot-melt pressure-sensitive adhesive for the heat-resistant high-viscosity woven cloth tape.

[0023] By adopting the above technical solution, the main polymer and the medium molecular weight polyisobutylene are first melted, which can effectively reduce the shear load, reduce the mixing time, and reduce the aging of the component materials, thereby saving costs. The hot melt pressure-sensitive adhesive prepared in the present application has excellent high temperature resistance and bonding strength, and the preparation method of the hot melt pressure-sensitive adhesive in the present application is simple and has high production efficiency.

[0024] Preferably, the molten mixture is cooled to 70-80° C., acrylonitrile and an initiator are added and mixed, and reacted for 3.5-4 hours to form a modified composite, and then the modified composite is mixed with a tackifying resin to form a hot melt pressure-sensitive adhesive mixture.

[0025] By adopting the above technical solution, at a certain temperature, acrylonitrile and initiator are added to the hot melt pressure sensitive adhesive system, so as to improve the initial adhesion, lasting adhesion and peeling strength of the hot melt pressure sensitive adhesive.

[0026] In summary, this application has the following beneficial effects:

[0027] 1. Since the molecular weight polyisobutylene in this application is added to the hot melt pressure sensitive adhesive system, it replaces the traditional process naphthenic oil diluent, improves the initial viscosity and cohesion of the hot melt pressure sensitive adhesive, thereby improving the bonding performance and weather resistance of the hot melt pressure sensitive adhesive. By adding a tackifying resin made of C5 petroleum resin and maple resin, the high temperature adhesion of the hot melt pressure sensitive adhesive is enhanced, and the high temperature resistance of the hot melt pressure sensitive adhesive is improved.

[0028] 2. In the present application, maleic anhydride, acrylonitrile and polyethylene wax are added to the hot melt pressure-sensitive adhesive system. Under the catalytic action of the initiator, acrylonitrile improves the flexibility of the hot melt pressure-sensitive adhesive, maleic anhydride improves the bonding strength and heat resistance of the hot melt pressure-sensitive adhesive, polyethylene wax can promote the uniform dispersion of maleic anhydride in the hot melt pressure-sensitive adhesive system, and polyethylene wax can also improve the wettability of the hot melt pressure-sensitive adhesive and the substrate. Maleic anhydride, acrylonitrile and polyethylene wax are compounded and strengthened with each other, thereby improving the bonding strength and temperature resistance of the hot melt pressure-sensitive adhesive and promoting better bonding between the hot melt pressure-sensitive adhesive and the substrate. DETAILED DESCRIPTION

[0029] The present application is further described in detail below with reference to the embodiments.

[0030] The host polymer was purchased from Kraton Polymers.

[0031] Antioxidant 1010 and antioxidant 168 were purchased from BASF.

[0032] Example 1

[0033] A heat-resistant high-viscosity hot-melt pressure-sensitive adhesive for a woven cloth tape comprises the following raw materials in parts by weight: 30 kg of a main polymer, 45 kg of a tackifying resin, 20 kg of a medium-molecular-weight polyisobutylene, and 0.5 kg of an antioxidant, wherein the main polymer is a mixture of styrene-ethylene-butylene-styrene block copolymer and styrene-butadiene-styrene triblock copolymer in a mass ratio of 1.2:1, the tackifying resin is a mixture of C5 petroleum resin and maple resin in a mass ratio of 1:0.7, the medium-molecular-weight polyisobutylene has a number average molecular weight of 40,000, and the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1.

[0034] The preparation method of the hot-melt pressure-sensitive adhesive for the heat-resistant high-viscosity woven cloth tape comprises the following specific steps:

[0035] S1: firstly, the main polymer, the antioxidant and the medium molecular weight polyisobutylene are mixed, the temperature is raised to 145° C., and heated for 40 minutes to obtain a molten mixture;

[0036] S2: then the molten mixture is mixed with the tackifying resin, the reaction is closed, and the mixture is stirred under vacuum at a speed of 100 r / min for 40 min until no bubbles are generated, and the heating is stopped to form a hot melt pressure-sensitive adhesive mixture;

[0037] S3: Finally, the hot melt pressure-sensitive adhesive mixture is filtered through a 150-mesh double-layer metal mesh, coated on the surface of the release paper, and packaged after cooling to obtain a hot melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven cloth tape.

[0038] Example 2-3

[0039] The difference between Example 2-3 and Example 1 is that the contents of the components in the hot-melt pressure-sensitive adhesive raw material are different, as shown in Table 1 for details.

[0040] Table 1: Content of each component in Examples 1-3

[0041]

[0042] Example 4

[0043] The difference between Example 4 and Example 1 is that the amount of the main polymer in the hot-melt pressure-sensitive adhesive raw material is 25 kg, the amount of the tackifying resin is 45 kg, the amount of the medium molecular weight polyisobutylene is 30 kg, and the amount of the antioxidant is 1 kg, wherein the main polymer is a mixture of styrene-ethylene-butylene-styrene block copolymer and styrene-butadiene-styrene triblock copolymer in a mass ratio of 1:1, the tackifying resin is a mixture of C5 petroleum resin and maple resin in a mass ratio of 1:0.5, and the number average molecular weight of the medium molecular weight polyisobutylene is 45,000.

[0044] The preparation method of the hot-melt pressure-sensitive adhesive for the heat-resistant high-viscosity woven cloth tape comprises the following specific steps:

[0045] S1: firstly, the main polymer, the antioxidant and the medium molecular weight polyisobutylene are mixed, the temperature is raised to 145° C., and heated for 35 minutes to obtain a molten mixture;

[0046] S2: then mix the molten mixture with the tackifying resin, react in a closed manner, evacuate and stir at a speed of 60 r / min for 50 min until no bubbles are generated, stop heating, and form a hot melt pressure-sensitive adhesive mixture;

[0047] S3: Finally, the hot melt pressure-sensitive adhesive mixture is filtered through a 150-mesh double-layer metal mesh, coated on the surface of the release paper, and packaged after cooling to obtain a hot melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven cloth tape.

[0048] Example 5

[0049] The difference between Example 5 and Example 1 is that the amount of the main polymer in the hot-melt pressure-sensitive adhesive raw material is 35 kg, the amount of the tackifying resin is 45 kg, the amount of the medium molecular weight polyisobutylene is 20 kg, and the amount of the antioxidant is 0.3 kg, wherein the main polymer is a mixture of styrene-ethylene-butylene-styrene block copolymer and styrene-butadiene-styrene triblock copolymer in a mass ratio of 1.5:1, the tackifying resin is a mixture of C5 petroleum resin and maple resin in a mass ratio of 1:0.8, and the number average molecular weight of the medium molecular weight polyisobutylene is 35,000.

[0050] The preparation method of the hot-melt pressure-sensitive adhesive for the heat-resistant high-viscosity woven cloth tape comprises the following specific steps:

[0051] S1: firstly, the main polymer, the antioxidant and the medium molecular weight polyisobutylene are mixed, the temperature is raised to 145° C., and heated for 30 minutes to obtain a molten mixture;

[0052] S2: then mix the molten mixture with the tackifying resin, react in a closed manner, evacuate and stir at a speed of 80 r / min for 45 min until no bubbles are generated, stop heating, and form a hot melt pressure-sensitive adhesive mixture;

[0053] S3: Finally, the hot melt pressure-sensitive adhesive mixture is filtered through a 150-mesh double-layer metal mesh, coated on the surface of the release paper, and packaged after cooling to obtain a hot melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven cloth tape.

[0054] Example 6

[0055] The difference between Example 6 and Example 1 is that the hot melt pressure-sensitive adhesive raw material also includes 2 kg of acrylonitrile and 0.4 kg of initiator, wherein the initiator is tert-butyl hydroperoxide.

[0056] The preparation method of the hot-melt pressure-sensitive adhesive for the heat-resistant high-viscosity woven cloth tape comprises the following specific steps:

[0057] S1: First, the main polymer, antioxidant and medium molecular weight polyisobutylene are mixed, the temperature is raised to 145°C, and heated for 40 minutes to obtain a molten mixture, the molten mixture is cooled to 75°C, acrylonitrile and initiator are added, mixed, and reacted for 3.5 hours to form a modified composite;

[0058] S2: then the modified composite is mixed with the tackifying resin, the reaction is closed, and the mixture is stirred under vacuum at a speed of 100 r / min for 40 min until no bubbles are generated, and the heating is stopped to form a hot melt pressure-sensitive adhesive mixture;

[0059] S3: Finally, the hot melt pressure-sensitive adhesive mixture is filtered through a 150-mesh double-layer metal mesh, coated on the surface of the release paper, and packaged after cooling to obtain a hot melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven cloth tape.

[0060] Example 7

[0061] The difference between Example 7 and Example 6 is that the amount of acrylonitrile used in the hot melt pressure-sensitive adhesive raw material is 3 kg and the initiator is 0.5 kg.

[0062] Example 8

[0063] The difference between Example 8 and Example 6 is that the amount of acrylonitrile used in the hot melt pressure-sensitive adhesive raw material is 1 kg and the initiator is 0.3 kg.

[0064] Example 9

[0065] The difference between Example 9 and Example 6 is that the hot melt pressure-sensitive adhesive raw material further includes 4 kg of maleic anhydride and 2 kg of polyethylene wax, wherein the molecular weight of the polyethylene wax is 3000.

[0066] The preparation method of the hot-melt pressure-sensitive adhesive for the heat-resistant high-viscosity woven cloth tape comprises the following specific steps:

[0067] S1: firstly, the main polymer, antioxidant, maleic anhydride, polyethylene wax, initiator and medium molecular weight polyisobutylene are mixed, the temperature is raised to 145°C, and the reaction is carried out for 1 hour to obtain a molten mixture, the molten mixture is cooled to 75°C, acrylonitrile is added and mixed, and the reaction is carried out for 3.5 hours to form a modified composite;

[0068] S2: then the modified composite is mixed with the tackifying resin, the reaction is closed, and the mixture is stirred under vacuum at a speed of 100 r / min for 40 min until no bubbles are generated, and the heating is stopped to form a hot melt pressure-sensitive adhesive mixture;

[0069] S3: Finally, the hot melt pressure-sensitive adhesive mixture is filtered through a 150-mesh double-layer metal mesh, coated on the surface of the release paper, and packaged after cooling to obtain a hot melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven cloth tape.

[0070] Example 10

[0071] The difference between Example 10 and Example 9 is that the amount of maleic anhydride used in the hot melt pressure-sensitive adhesive raw material is 5 kg, and the amount of polyethylene wax used is 3 kg.

[0072] Embodiment 11

[0073] The difference between Example 11 and Example 9 is that the amount of maleic anhydride used in the hot melt pressure-sensitive adhesive raw material is 3 kg, and the amount of polyethylene wax used is 1 kg.

[0074] Example 12

[0075] The difference between Example 12 and Example 9 is that polyethylene wax is not used in the hot melt pressure-sensitive adhesive raw material.

[0076] Example 13

[0077] The difference between Example 13 and Example 9 is that the hot melt pressure-sensitive adhesive raw material further includes 0.8 kg of 2-hydroxy-4-n-octyloxybenzophenone.

[0078] The preparation method of the hot-melt pressure-sensitive adhesive for the heat-resistant high-viscosity woven cloth tape comprises the following specific steps:

[0079] S1: firstly, a main polymer, an antioxidant, maleic anhydride, polyethylene wax, an initiator, 2-hydroxy-4-n-octyloxybenzophenone and a medium molecular weight polyisobutylene are mixed, the temperature is raised to 145°C, and the mixture is heated for reaction for 1 hour to obtain a molten mixture, the molten mixture is cooled to 75°C, acrylonitrile is added, mixed, and reacted for 3.5 hours to form a modified composite;

[0080] S2: then the modified composite is mixed with the tackifying resin, the reaction is closed, and the mixture is stirred under vacuum at a speed of 100 r / min for 40 min until no bubbles are generated, and the heating is stopped to form a hot melt pressure-sensitive adhesive mixture;

[0081] S3: Finally, the hot melt pressure-sensitive adhesive mixture is filtered through a 150-mesh double-layer metal mesh, coated on the surface of the release paper, and packaged after cooling to obtain a hot melt pressure-sensitive adhesive for a heat-resistant and high-viscosity woven cloth tape.

[0082] Embodiment 14

[0083] The difference between Example 14 and Example 13 is that the amount of 2-hydroxy-4-n-octyloxybenzophenone used in the hot melt pressure-sensitive adhesive raw material is 1 kg.

[0084] Embodiment 15

[0085] The difference between Example 15 and Example 13 is that the usage amount of 2-hydroxy-4-n-octyloxybenzophenone in the hot melt pressure-sensitive adhesive raw material is 0.5 kg.

[0086] Comparative Example

[0087] Comparative Example 1

[0088] The difference between Comparative Example 1 and Example 1 is that the tackifying resin in the hot melt pressure sensitive adhesive raw material is C5 petroleum resin.

[0089] Comparative Example 2

[0090] The difference between Comparative Example 2 and Example 1 is that the medium molecular weight polyisobutylene in the hot melt pressure sensitive adhesive raw material is replaced by an equal amount of low molecular weight polyisobutylene, wherein the molecular weight of the low molecular weight polyisobutylene is 2500.

[0091] Comparative Example 3

[0092] The difference between Comparative Example 3 and Example 1 is that the medium molecular weight polyisobutylene in the hot melt pressure sensitive adhesive raw material is replaced by an equal amount of cyclohexane oil.

[0093] Performance testing

[0094] The following performance tests were conducted on the heat-resistant and high-viscosity woven cloth tape with hot-melt pressure-sensitive adhesive provided in Examples 1-15 and Comparative Examples 1-3 of the present application. The test results are shown in Table 2.

[0095] Detection Methods

[0096] 1. Initial viscosity

[0097] The initial adhesion performance of hot melt pressure sensitive adhesive was tested with reference to GB / T4852-2002 "Test method for initial adhesion of pressure sensitive adhesive tapes (rolling ball method)". The experimental conditions were: 23±2℃, 50±5%RH.

[0098] 2. 180° peel strength

[0099] Referring to the standard of GB / T2792-1998 "Test method for 180° peel strength of pressure-sensitive tape", the 180° peel strength of hot-melt pressure-sensitive adhesive was tested. The sample width was 25 mm and the test speed was 300 mm / min.

[0100] 3. Maintaining stickiness

[0101] Refer to the standard of Method A in GB / T4851-2014 "Test method for adhesive tape holding property" to test the vertical holding property of hot melt pressure sensitive adhesive. The bonding area is 25×25mm 2 , loading mass is 1000g, experimental conditions: 23±2℃, 50±5%RH.

[0102] 4. High temperature viscosity

[0103] Refer to the standard of method G in GB / T4851-2014 "Test method for adhesive tape holding property" to test the high temperature vertical holding property of hot melt pressure sensitive adhesive, and the bonding area is 25×25mm 2 , loading mass is 1000g, pretreatment: place the sample at 23±2℃, 50±5%RH for 20min, and then test the high temperature vertical adhesion of the hot melt pressure-sensitive adhesive at 50℃.

[0104] Table 2: Performance test data table

[0105]

[0106]

[0107] It can be seen from the performance test results of Examples 1-5 that the hot melt pressure-sensitive adhesive prepared in the examples of the present application has excellent bonding properties, and at a certain high temperature, the hot melt pressure-sensitive adhesive still has good holding force, which further illustrates that the hot melt pressure-sensitive adhesive prepared in the examples of the present application has good high temperature resistance. The hot melt pressure-sensitive adhesive prepared in the present application uses medium molecular weight polyisobutylene to replace traditional cyclohexane oil as a diluent, which makes the hot melt pressure-sensitive adhesive have excellent initial adhesion and cohesion, and is not affected by seasonal temperature changes, and has good high temperature resistance and weather resistance. In Examples 1-5, the usage amount of each component is different, and the usage amount in Example 1 is more suitable. At the same time, C5 petroleum resin and maple resin are compounded and strengthened as tackifying resins in the examples of the present application, and added to the hot melt pressure-sensitive adhesive, which improves the adhesion and high temperature resistance of the hot melt pressure-sensitive adhesive, and C5 petroleum resin can improve the cohesion of the hot melt pressure-sensitive adhesive, which makes the hot melt pressure-sensitive adhesive have good holding force, peel strength and temperature resistance, and the softening point of maple resin is low, which can improve the initial adhesion performance of the hot melt pressure-sensitive adhesive.

[0108] In Examples 6-8, acrylonitrile is added to the hot melt pressure sensitive adhesive system, and the polar groups of acrylonitrile are introduced into the molecular chains of the hot melt pressure sensitive adhesive components, thereby improving the polarity of the hot melt pressure sensitive adhesive and promoting better wettability and adhesion between the hot melt pressure sensitive adhesive and the substrate. The test results show that the initial tack, peel strength and holding force of the hot melt pressure sensitive adhesive after adding acrylonitrile are significantly increased, further illustrating the promoting effect of acrylonitrile on the hot melt pressure sensitive adhesive.

[0109] In embodiments 9-11, maleic anhydride and polyethylene wax are added to the hot melt pressure sensitive adhesive system. It can be seen from the test results that maleic anhydride can be grafted onto styrene polymer molecules to improve the heat resistance of the hot melt pressure sensitive adhesive, and the polar groups of maleic anhydride are connected to the styrene polymer molecules to improve the cohesive strength and bonding properties of the hot melt pressure sensitive adhesive. Polyethylene wax can be combined with C5 petroleum resin and maple resin to adjust the viscosity of the hot melt pressure sensitive adhesive, reduce the phenomenon of sticky glue in the hot melt pressure sensitive adhesive, improve the fluidity of the hot melt pressure sensitive adhesive, promote the hot melt pressure sensitive adhesive and substrate to have better wettability, thereby further improving the initial adhesion and peel strength of the hot melt pressure sensitive adhesive. At the same time, polyethylene wax can also improve the water resistance of the hot melt pressure sensitive adhesive, and polyethylene wax forms a certain film-forming protection on the surface of the hot melt pressure sensitive adhesive to improve the waterproof performance of the hot melt pressure sensitive adhesive.

[0110] In Example 12, maleic anhydride is added to the hot melt pressure-sensitive adhesive system, and polyethylene wax is not used. It can be seen from the test results that the hot melt pressure-sensitive adhesive prepared in Example 12 still has good bonding properties. However, compared with the performance test results of Example 12 and Example 9, it can be seen that the holding force of the hot melt pressure-sensitive adhesive has a certain decrease. This may be because the free radicals of the polyethylene wax are connected to the maleic anhydride, thereby promoting the maleic anhydride to be evenly dispersed in the hot melt pressure-sensitive adhesive system, thereby promoting the hot melt pressure-sensitive adhesive to have better heat resistance and holding force.

[0111] In Examples 13-15, 2-hydroxy-4-n-octyloxybenzophenone is added to the hot melt pressure-sensitive adhesive system. From the test results, it can be seen that the holding force and peel strength of the hot melt pressure-sensitive adhesive are significantly increased, the aging resistance and light resistance of the hot melt pressure-sensitive adhesive are improved, the carbonyl index on the surface of the hot melt pressure-sensitive adhesive is reduced, and the ultraviolet light absorption of the hot melt pressure-sensitive adhesive is reduced, thereby promoting the hot melt pressure-sensitive adhesive to have better bonding strength and holding force with the substrate.

[0112] By comparing the performance test results of Comparative Example 1 and Example 1, it can be seen that the performance of the hot melt pressure-sensitive adhesive prepared in Comparative Example 1 is lower than the comprehensive performance of the hot melt pressure-sensitive adhesive prepared in Example 1, which further illustrates that the low softening point of maple resin has a significant promoting effect on the bonding performance of the hot melt pressure-sensitive adhesive.

[0113] By comparing the performance test results of Comparative Example 2 and Example 1, it can be seen that polyisobutylene with different molecular weights is used in Comparative Example 2. From the test results, it can be seen that the hot melt pressure-sensitive adhesive prepared in Comparative Example 2 still has certain bonding properties, but the temperature resistance of the hot melt pressure-sensitive adhesive in Comparative Example 2 is significantly lower than that in Example 1. This may be because the polyisobutylene with a number average molecular weight in the range of 35000-45000 has better viscosity and heat resistance.

[0114] By comparing the performance test results of Comparative Example 3 and Example 1, it can be seen that the comprehensive performance of the hot melt pressure-sensitive adhesive prepared in Comparative Example 3 is reduced by replacing the medium molecular weight polyisobutylene with the cyclohexane oil used in the traditional process. This further illustrates that the bonding performance of cyclohexane oil is greatly affected by temperature, and the medium molecular weight polyisobutylene has a better promoting effect on the bonding performance of the hot melt pressure-sensitive adhesive.

[0115] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A hot-melt pressure-sensitive adhesive for heat-resistant high-viscosity woven cloth tape, characterized in that: The invention comprises the following raw materials in parts by weight: 20-35 parts of a main polymer, 40-50 parts of a tackifying resin, 15-30 parts of medium molecular weight polyisobutylene, 0.3-1 parts of an antioxidant, 1-3 parts of acrylonitrile, 0.3-0.5 parts of an initiator, 3-5 parts of maleic anhydride and 1-3 parts of polyethylene wax; the main polymer is a mixture of styrene-ethylene-butylene-styrene block copolymer and styrene-butadiene-styrene triblock copolymer, the mass ratio of the styrene-ethylene-butylene-styrene block copolymer and the styrene-butadiene-styrene triblock copolymer is (1.5-1):1, the tackifying resin is a mixture of C5 petroleum resin and maple balsam, and the number average molecular weight of the medium molecular weight polyisobutylene is 35000-45000.

2. The heat-resistant high-viscosity hot-melt pressure-sensitive adhesive for woven cloth tape according to claim 1, characterized in that: The tackifying resin is a mixture of C5 petroleum resin and maple balsam resin in a mass ratio of 1: (0.8-0.5).

3. The heat-resistant high-viscosity hot-melt pressure-sensitive adhesive for woven cloth tape according to claim 1, characterized in that: The hot melt pressure sensitive adhesive raw material also includes 0.5-1 part of 2-hydroxy-4-n-octyloxybenzophenone.

4. A method for preparing a hot-melt pressure-sensitive adhesive for a heat-resistant high-viscosity woven cloth tape as claimed in any one of claims 1 to 3, characterized in that: The method comprises the following specific steps: firstly, mixing a main polymer, an antioxidant and a medium molecular weight polyisobutylene, heating to 140-150° C., heating for 30-40 minutes to obtain a molten mixture, and then mixing and stirring the molten mixture with a tackifying resin to form a hot melt pressure-sensitive adhesive mixture; Finally, the hot-melt pressure-sensitive adhesive mixture is filtered, coated on the surface of the release paper, and packaged after cooling to obtain the hot-melt pressure-sensitive adhesive for the heat-resistant high-viscosity woven cloth tape.

5. The method for preparing a heat-resistant high-viscosity woven cloth tape according to claim 4, characterized in that: The molten mixture is cooled to 70-80°C, acrylonitrile and initiator are added and mixed, and the mixture is reacted for 3.5-4 hours to form a modified composite, and then the modified composite is mixed with a tackifying resin to form a hot melt pressure-sensitive adhesive mixture.

Images