Hot-melt pressure-sensitive adhesive for high-density polyethylene and preparation method of hot-melt pressure-sensitive adhesive

Abstract

The invention relates to the technical field of C09J157 / 00, and the adhesive at least comprises the following components in parts by weight: 20-40 parts of a block copolymer, 30-50 parts of tackifying resin, 0.1-1 part of an antioxidant and 20-40 parts of rubber oil, and is designed aiming at a high-density polyethylene material, and the adhesive has the characteristics of excellent adhesive property and easy damage. The defects of an existing product in the aspects of weather resistance, adhesion and destructiveness are overcome, and the method is very important for improving the overall safety and convenience of express packaging.

Description

Technical Field

[0001] The invention relates to the technical field of C09J157 / 00, in particular to a hot-melt pressure-sensitive adhesive for high-density polyethylene and a preparation method thereof. Background Art

[0002] With the booming development of e-commerce, the express packaging industry has ushered in unprecedented growth. High-density polyethylene (HDPE) materials have become a common material for making express bags due to their lightness, durability and relatively low cost. However, it is equally important to ensure the safety and confidentiality of packages during the express delivery process. Traditional sealing tapes often cannot meet the demand for high viscosity of HDPE materials, and cannot provide an effective way to destroy them when the contents of the package need to be verified. Therefore, the development of a tape adhesive with excellent bonding properties and easy-to-destroy characteristics is crucial to improving the overall safety and convenience of express packaging. At present, there is limited research on the market for special applications such as HDPE material-made adhesives for destroying tapes, and existing products have deficiencies in weather resistance, adhesion and destructiveness. For example, some tapes may degrade in performance under harsh environments, or are not easily destroyed when the contents need to be verified. In addition, although the existing UV hot-melt pressure-sensitive adhesives have advantages in environmental protection, rapid curing, and high adhesion, they are still insufficient compared to hot-melt pressure-sensitive adhesives in finished products and equipment operation. A Chinese patent (authorization announcement number CN102181248B) discloses a hot-melt pressure-sensitive adhesive for polyethylene materials and a preparation method thereof. By optimizing the formula system to include materials such as petroleum resin and polyisobutylene, the initial adhesion of the product is improved. However, it cannot be used for high-density polyethylene materials while ensuring weather resistance, adhesion and destructiveness. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a hot-melt pressure-sensitive adhesive for high-density polyethylene, and designs a tape adhesive with excellent bonding properties and easy-to-destruct properties for high-density polyethylene materials, overcoming the shortcomings of existing products in weather resistance, adhesion and destructibility, which is crucial to improving the overall safety and convenience of express packaging.

[0004] On one hand, the present invention provides a hot melt pressure-sensitive adhesive for high-density polyethylene, which comprises at least the following components by weight: 20-40 parts of block copolymer, 30-50 parts of tackifying resin, 0.1-1 parts of antioxidant and 20-40 parts of rubber oil.

[0005] As a preferred technical solution, the raw materials for preparing the hot melt pressure-sensitive adhesive for high-density polyethylene include at least the following components by weight: 28-32 parts of block copolymer, 38-42 parts of tackifying resin, 0.1-0.3 parts of antioxidant, and 25.8-33.8 parts of rubber oil.

[0006] As a preferred technical solution, the block copolymer at least includes polystyrene-polybutadiene-polystyrene block copolymer (SBS), polystyrene-polyisoprene-polystyrene block copolymer (SIS), and styrene-butadiene block copolymer (SBR).

[0007] As a preferred technical solution, the mass ratio of the polystyrene-polybutadiene-polystyrene block copolymer, the polystyrene-polyisoprene-polystyrene block copolymer, and the styrene-butadiene block copolymer is (5-10):(10-20):(2-10), preferably 8:(14-18):6, and further preferably 8:(15-17):6.

[0008] As a preferred technical solution, the structure of the polystyrene-polybutadiene-polystyrene block copolymer (SBS) is one of a linear structure, a star structure or a star-line mixed structure, preferably a linear structure.

[0009] As a preferred technical solution, the styrene content of the polystyrene-polybutadiene-polystyrene block copolymer (SBS) is 28-32wt%, preferably 32wt%.

[0010] As a preferred technical solution, the melt index (230°C, 2.16kg) of the polystyrene-polybutadiene-polystyrene block copolymer (SBS) is 3-8g / 10min, preferably 6g / 10min.

[0011] Most preferably, the polystyrene-polybutadiene-polystyrene block copolymer (SBS) is YH-188 (Baling Petrochemical 188).

[0012] As a preferred technical solution, the structure of the polystyrene-polyisoprene-polystyrene block copolymer (SIS) is a linear structure, a star structure or a coupled linear structure, preferably a star structure.

[0013] As a preferred technical solution, the diblock content (SI content) of the polystyrene-polyisoprene-polystyrene block copolymer (SIS) is 50-70wt%, preferably 32wt%.

[0014] As a preferred technical solution, the melt index (200°C, 5kg) of the polystyrene-polybutadiene-polystyrene block copolymer (SBS) is 15-25g / 10min, preferably 23g / 10min.

[0015] As a preferred technical solution, the polystyrene-polyisoprene-polystyrene block copolymer (SIS) is preferably YH-4016 (Baling Petrochemical 4016).

[0016] As a preferred technical solution, the styrene-butadiene block copolymer (SBR) is selected from at least one of emulsion-polymerized styrene-butadiene rubber (ESBR) and solution-polymerized styrene-butadiene rubber (SSBR), preferably solution-polymerized styrene-butadiene rubber (SSBR).

[0017] As a preferred technical solution, the tackifying resin at least includes phenol-modified rosin resin, rosin-modified resin and rosin pentaerythritol ester.

[0018] As a preferred technical solution, the mass ratio of the phenol-modified rosin resin, the rosin-modified resin and the rosin pentaerythritol ester is (3-7):(10-30):(10-20), preferably (3-7):20:15.

[0019] As a preferred technical solution, the softening point (ring and ball method) of the phenol-modified rosin resin is 130-160°C, preferably 145-155°C, and the model is K803L.

[0020] As a preferred technical solution, the softening point (ring and ball method) of the rosin pentaerythritol ester is 80-120°C, preferably 99-107°C, and the model is RESIN 146.

[0021] As a preferred technical solution, the antioxidant is a hindered phenol antioxidant, preferably antioxidant 1010.

[0022] As a preferred technical solution, the rubber oil is cyclohexane oil or white mineral oil, preferably cyclohexane oil (Kunlun 4010).

[0023] The hot melt pressure sensitive adhesive provided by the present invention has excellent initial adhesion, bonding strength and high temperature resistance by optimizing the coordination of SBS, SIS and SSBR, tackifying resin, rubber oil and antioxidant in the system and controlling the addition amount. Specifically, the present invention adopts a main polymer system including YH-188, YH-4016 and solution-polymerized styrene butadiene rubber (SSBR), especially controlling the mass ratio of the three to be 8: (14-18): 6, effectively improving the initial adhesion of the product while improving the bonding strength of the product. Further, by introducing phenol-modified rosin resin, rosin-modified resin and rosin pentaerythritol ester with a mass ratio of (3-7): (10-30): (10-20), and coordinating with the main polymer system, the bonding performance, wettability and polarity of the hot melt pressure sensitive adhesive are improved. In addition, in the present invention, by introducing cyclopentane oil (Kunlun 4010), the compatibility between the main polymer and the resin is improved, thereby improving the bonding strength of the hot melt adhesive.

[0024] On the other hand, the present invention provides a method for preparing a hot melt pressure-sensitive adhesive for high-density polyethylene, which comprises at least the following steps: heating the block copolymer and rubber oil at 110-150°C for 60-90 minutes, adding a tackifying resin and an antioxidant, heating the mixture to 130-150°C and subjecting the mixture to a vacuum treatment for 30-60 minutes to obtain the hot melt pressure-sensitive adhesive.

[0025] The hot-melt pressure-sensitive adhesive for high-density polyethylene provided by the present invention is green, environmentally friendly, and non-irritating, and can better meet the practical application requirements of high-density polyethylene express bags.

[0026] Beneficial Effects

[0027] 1. The present invention provides a hot-melt pressure-sensitive adhesive for high-density polyethylene. A tape adhesive with excellent bonding properties and easy-to-destruct properties is designed for high-density polyethylene materials, which overcomes the shortcomings of existing products in terms of weather resistance, adhesion and destructibility, and is crucial to improving the overall safety and convenience of express packaging.

[0028] 2. The hot melt pressure-sensitive adhesive provided by the present invention optimizes the combination of SBS, SIS and SSBR, tackifying resin, rubber oil and antioxidant in the system and controls the addition amount, so that the provided product has excellent initial adhesion, bonding strength and high temperature resistance.

[0029] 3. The present invention adopts a main polymer system including YH-188, YH-4016 and solution butadiene styrene rubber (SSBR), especially controlling the mass ratio of the three to 8: (14-18): 6, thereby effectively improving the initial adhesion performance of the product and improving the bonding strength of the product.

[0030] 4. The present invention improves the bonding performance, wettability and polarity of the hot melt pressure-sensitive adhesive by introducing phenol-modified rosin resin, rosin-modified resin and rosin pentaerythritol ester in a mass ratio of (3-7): (10-30): (10-20) and coordinating them with the main polymer system.

[0031] 5. The hot-melt pressure-sensitive adhesive for high-density polyethylene provided by the present invention is green, environmentally friendly, and non-irritating, and can better meet the practical application requirements of high-density polyethylene express bags. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a diagram of the actual test results of the product provided in Example 1 of the present invention.

[0033] Figure 2 This is a diagram of the actual test results of the product provided in Example 2 of the present invention.

[0034] Figure 3 This is a diagram of the actual test results of the product provided in Example 3 of the present invention.

[0035] Figure 4 This is a diagram of the actual test results of the product provided in Example 4 of the present invention.

[0036] Figure 5 This is a diagram of the actual test results of the product provided in Example 5 of the present invention.

[0037] Figure 6 This is a diagram of the actual test results of the product provided in Example 6 of the present invention. DETAILED DESCRIPTION

[0038] Examples 1-6

[0039] On the one hand, Examples 1-6 of the present invention provide a hot melt pressure-sensitive adhesive for high-density polyethylene. The formulas are shown in Table 1 and Table 2 in parts by weight.

[0040] Table 1

[0041]

[0042]

[0043] Table 2

[0044]

[0045] On the other hand, Examples 1-6 of the present invention provide a method for preparing a hot-melt pressure-sensitive adhesive for high-density polyethylene, comprising the following steps: referring to Tables 1 and 2, the block copolymer, rubber oil and antioxidant are heated at 130°C for 60 minutes, then a tackifying resin is added, the temperature is raised to 145°C and a vacuum treatment is performed for 40 minutes to obtain the product.

[0046] Performance Testing

[0047] 1. The viscosity of the hot melt pressure sensitive adhesives provided in Examples 1-6 was tested according to HG / T 3660-1999 standard. The results are shown in Table 2.

[0048] 2. The softening points of the hot melt pressure sensitive adhesives provided in Examples 1-6 were tested according to GB / T 15332-1994 (ring and ball method). The results are shown in Table 2.

[0049] 3. The bonding strength of the hot melt pressure-sensitive adhesives provided in Examples 1-6 was tested with reference to GB / T 2792-2014. The results are shown in Table 2.

[0050] 4. Actual pasting test: The actual pasting test was carried out in a constant temperature and humidity laboratory (23±1°C, 50±5%RH). The hot melt pressure sensitive adhesive provided in Examples 1-3 was used for labeling and the label was immediately torn off. The amount of adhesive applied was controlled at 95±5gsm. The test results are shown in Figure 1-3 .

[0051] Table 2

[0052]

Claims

1. A hot melt pressure-sensitive adhesive for high-density polyethylene, characterized in that: The invention comprises at least the following components by weight: 20-40 parts of block copolymer, 30-50 parts of tackifying resin, 0.1-1 parts of antioxidant and 20-40 parts of rubber oil.

2. The hot melt pressure-sensitive adhesive for high-density polyethylene according to claim 1, characterized in that: The raw materials for preparing the hot melt pressure-sensitive adhesive for high-density polyethylene include at least the following components by weight: 28-32 parts of block copolymer, 38-42 parts of tackifying resin, 0.1-0.3 parts of antioxidant, and 25.8-33.8 parts of rubber oil.

3. The hot melt pressure-sensitive adhesive for high-density polyethylene according to claim 1 or 2, characterized in that: The block copolymer at least includes polystyrene-polybutadiene-polystyrene block copolymer, polystyrene-polyisoprene-polystyrene block copolymer and styrene-butadiene block copolymer.

4. The hot melt pressure-sensitive adhesive for high-density polyethylene according to claim 3, characterized in that: The mass ratio of the polystyrene-polybutadiene-polystyrene block copolymer, the polystyrene-polyisoprene-polystyrene block copolymer and the styrene-butadiene block copolymer is (5-10): (10-20): (2-10).

5. The hot melt pressure-sensitive adhesive for high-density polyethylene according to claim 4, characterized in that: The structure of the polystyrene-polybutadiene-polystyrene block copolymer is one of a linear structure, a star structure or a star-line mixed structure.

6. The hot melt pressure-sensitive adhesive for high-density polyethylene according to claim 5, characterized in that: The polystyrene-polybutadiene-polystyrene block copolymer has a styrene content of 28-32 wt %.

7. The hot melt pressure-sensitive adhesive for high-density polyethylene according to claim 6, characterized in that: The tackifying resin at least includes phenol-modified rosin resin, rosin-modified resin and rosin pentaerythritol ester.

8. The hot melt pressure-sensitive adhesive for high-density polyethylene according to claim 7, characterized in that: The mass ratio of the phenol-modified rosin resin, the rosin-modified resin and the rosin pentaerythritol ester is (3-7): (10-30): (10-20).

9. The hot melt pressure-sensitive adhesive for high-density polyethylene according to claim 8, characterized in that: The antioxidant is a hindered phenol antioxidant.

10. A method for preparing a hot melt pressure-sensitive adhesive for high-density polyethylene according to any one of claims 1 to 9, characterized in that: At least the following steps are included: The block copolymer and rubber oil are heated at 110-150° C. for 60-90 minutes, and then tackifying resin and antioxidant are added, and the temperature is raised to 130-150° C. and vacuum treatment is carried out for 30-60 minutes to obtain the product.

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