Uniaxially oriented polypropylene film protective adhesive tape and preparation method thereof

Abstract

The invention relates to the technical field of pressure-sensitive adhesives, in particular to a one-way stretching polypropylene film protective adhesive tape and a preparation method thereof, the one-way stretching polypropylene film protective adhesive tape comprises a base material layer and an adhesive layer; the adhesive layer at least comprises the following raw materials in parts by weight: 8-20 parts of butyl acrylate, 12-32 parts of 2-ethylhexyl acrylate, 4-14 parts of methyl methacrylate, 1-7 parts of acrylic acid, 1-6 parts of hydroxyethyl methylacrylate, 1-6 parts of a functional monomer, 40-60 parts of a solvent, 0.3-2 parts of an initiator and 0.8-2 parts of a curing agent; by taking the uniaxially stretched polypropylene film as a base material and optimizing an adhesive layer formula system, the provided protective adhesive tape meets the adhesive property requirement, does not have adhesive residue, and is particularly suitable for adhesive fixation and paint spraying protection of various electronic and electrical moving parts.

Description

Technical Field

[0001] This invention relates to the field of pressure-sensitive adhesive technology, specifically to a uniaxially oriented polypropylene film protective tape and its preparation method. Background Technology

[0002] Protective tape is a functional material widely used in the manufacturing or use of electronic, electrical, microelectronic, integrated packaging, and electrical equipment to provide protection. With technological advancements, the performance requirements for tapes are becoming increasingly stringent. Chinese patent (authorization announcement number CN117801702B) discloses a high-adhesion, ultra-thin, high-temperature resistant protective tape and its preparation method. By using a polyimide film and a pressure-sensitive adhesive layer in the protective tape, with a primer placed between them and a barrier layer on the other side, the problems of poor adhesion and VOC overflow at high temperatures are solved, achieving high adhesion, high temperature resistance, and low volatility. However, when used for bonding and fixing various electronic and electrical moving parts or for paint protection, adhesive residue remains after peeling, requiring subsequent cleaning. Summary of the Invention

[0003] To address the aforementioned issues, this invention provides a uniaxially oriented polypropylene film protective tape. By using uniaxially oriented polypropylene film as the substrate and incorporating an optimized adhesive formulation system, the provided protective tape meets bonding performance requirements while leaving no residue. It is particularly suitable for bonding and fixing various electronic and electrical moving parts and for paint protection.

[0004] This invention provides a uniaxially oriented polypropylene film protective tape, comprising a substrate layer and an adhesive layer; by weight, the adhesive layer comprises at least the following raw materials: 8-20 parts butyl acrylate, 12-32 parts isooctyl acrylate, 4-14 parts methyl methacrylate, 1-7 parts acrylic acid, 1-6 parts hydroxyethyl methacrylate, 1-6 parts functional monomer, 40-60 parts solvent, 0.3-2 parts initiator, and 0.8-2 parts curing agent.

[0005] In one embodiment, the substrate layer is a uniaxially oriented polypropylene film.

[0006] In one embodiment, the adhesive layer comprises, by weight, at least the following raw materials: 10-15 parts butyl acrylate, 15-30 parts isooctyl acrylate, 5-10 parts methyl methacrylate, 2-5 parts acrylic acid, 2-5 parts hydroxyethyl methacrylate, 2-5 parts functional monomer, 45-48 parts solvent, 0.5-0.9 parts initiator, and 1-1.3 parts curing agent.

[0007] This invention, through the combination and control of the amount of each acrylic monomer added, provides a product that simultaneously possesses excellent peel strength, initial tack, holding power, and tensile strength, and leaves no residue upon removal, eliminating cleaning hassles and protecting the surface of the adhered object.

[0008] In one embodiment, the functional monomer is selected from at least one of polyethylene glycol diacrylate, lauryl acrylate, caprolactone methacrylate, β-carboxyethyl acrylate (β-CEA), glycidyl methacrylate (GMA), isobornyl methacrylate (IBOMA), isobornyl acrylate (IBOA), hydroxyethyl modified acrylamide (HEAA), trimethylolpropane trimethacrylate (TMPTMA), phosphate methacrylate (PM-3), monofunctional stretchable acrylate (SW611), acrylmorpholine (ACMO), dipentaerythritol hexaacrylate (DPHA), ethoxytrimethylolpropane triacrylate (TMP3), pentaerythritol tetrakis(3-mercaptopropionic acid) ester (PETMP), hydroxybutyl acrylate (4HBA), fluorinated acrylic monomer (SW613), dimethylaminoethyl methacrylate (DMAEMA), dimethylaminoethyl acrylate (DMAEA), hydroxyethyl methacrylate (HEMA), or hydroxyethyl acrylate (HEA).

[0009] Based on the acrylic monomers in the system, by introducing 2-5 parts by weight of functional monomers, especially any one of polyethylene glycol diacrylate, lauryl acrylate, caprolactone methacrylate, β-carboxyethyl acrylate (β-CEA), glycidyl methacrylate (GMA), isobornyl methacrylate (IBOMA), isobornyl acrylate (IBOA), and hydroxyethyl modified acrylamide (HEAA), the bonding strength between the adhesive layer and the substrate layer is guaranteed. At the same time, after bonding PP (polypropylene), PE (polyethylene), ABS (acrylonitrile-butadiene-styrene plastic), stainless steel plate, glass plate, painted plate and other materials, no adhesive residue is left after removal, reducing the number of steps to clean up adhesive residue and better meeting the needs of practical applications.

[0010] In one embodiment, the solvent is selected from at least one of ester solvents or ketone solvents.

[0011] In one embodiment, the ester solvent is selected from at least one of ethyl acetate, n-propyl acetate, isopropyl acetate, or butyl acetate.

[0012] In one embodiment, the ketone solvent is selected from at least one of acetone, methyl ethyl ketone, or methyl isobutyl ketone.

[0013] In one embodiment, the initiator is selected from at least one of peroxide initiators or azo initiators.

[0014] In one embodiment, the peroxide initiator is selected from at least one of benzoyl peroxide (BPO), lauroyl peroxide (LPO), or peroxide dicarbonate (such as BPPD, EHP).

[0015] In one embodiment, the azo initiator is selected from at least one of azobisisobutyronitrile (AIBN) or azobisisoheptanenitrile (ABVN).

[0016] This invention introduces 0.5 to 0.9 parts of AIBN or BPO as an initiator, and, in conjunction with process condition control, effectively balances the reaction rate and controls side reactions, ensuring complete monomer reaction and guaranteeing the performance of the adhesive layer.

[0017] In one embodiment, the curing agent is selected from at least one of isocyanates, epoxy resins, or aluminum acetylacetonate.

[0018] In one embodiment, the epoxy is selected from at least one of TDE-85 (triglycidyl isocyanurate), tetraglycidyl diaminodiphenylmethane (TGDDM), and triglycidyl p-aminophenol (TGPAP).

[0019] This invention effectively increases the crosslinking density by using isocyanates, epoxy compounds, or aluminum acetylacetonate as curing agents, avoiding the problem of residual adhesive after coating while ensuring the toughness of the adhesive layer, thus expanding the application range of protective tape.

[0020] Another aspect of the present invention provides a method for preparing uniaxially oriented polypropylene film protective tape, comprising at least the following steps: adding butyl acrylate, isooctyl acrylate, methyl methacrylate, acrylic acid, hydroxyethyl methacrylate, functional monomers, solvent, and 20-40 wt% of the total amount of initiator to a reaction vessel, using a one-pot method, initiating the reaction at 80-90°C, adjusting the temperature to 75-85°C after initiation, starting to add the remaining initiator dropwise, completing the dropwise addition in 3-4 hours, continuing the reaction for another 3-4 hours to obtain adhesive, mixing the adhesive with a curing agent and coating it onto the surface of a substrate, and curing to form an adhesive layer on the surface of the substrate.

[0021] In one embodiment, the curing temperature is 100-120°C.

[0022] In one embodiment, the thickness of the adhesive layer is 20-30 μm.

[0023] Beneficial effects

[0024] 1. This invention provides a uniaxially oriented polypropylene film protective tape. By using uniaxially oriented polypropylene film as the substrate and combining it with an optimized adhesive layer formulation system, the provided protective tape meets the bonding performance requirements without leaving any residue. It is especially suitable for bonding and fixing various electronic and electrical moving parts and for paint protection.

[0025] 2. By combining and controlling the amount of each acrylic monomer, this invention provides a product that simultaneously possesses excellent peel strength, initial tack, holding power, and tensile strength, and leaves no residue upon removal, eliminating cleaning hassles and protecting the surface of the adhered object.

[0026] 3. Based on the acrylic monomers in the system, by introducing 2-5 parts by weight of functional monomers, especially any one of polyethylene glycol diacrylate, lauryl acrylate, caprolactone methacrylate, β-carboxyethyl acrylate, glycidyl methacrylate, isobornyl methacrylate, isobornyl acrylate, and hydroxyethyl modified acrylamide, the bonding strength between the adhesive layer and the substrate layer is guaranteed. At the same time, after bonding PP (polypropylene), PE (polyethylene), ABS (acrylonitrile-butadiene-styrene plastic), stainless steel plate, glass plate, painted plate and other boards, no adhesive residue is left after removal, reducing the number of steps to clean up adhesive residue and better meeting the needs of practical applications.

[0027] 4. By introducing 0.5 to 0.9 parts of AIBN or BPO as an initiator and controlling the process conditions, this invention effectively balances the reaction rate and controls the side reactions, ensuring complete monomer reaction and guaranteeing the performance of the adhesive layer.

[0028] 5. By using isocyanates, epoxy compounds, or aluminum acetylacetonate as curing agents, this invention effectively increases the crosslinking density, avoids the problem of residual adhesive after coating, and ensures the toughness of the adhesive layer, thus expanding the application range of the protective tape. Detailed Implementation

[0029] Examples 1-3, Comparative Examples 1-3

[0030] Examples 1-3 and Comparative Examples 1-3 of the present invention provide a uniaxially oriented polypropylene film protective tape, comprising a substrate layer and an adhesive layer, wherein the substrate layer is a uniaxially oriented polypropylene film; the formulation of the adhesive layer by weight is shown in Table 1.

[0031] Table 1

[0032]

[0033]

[0034] Examples 1-3 and Comparative Examples 1-3 of the present invention provide a method for preparing uniaxially oriented polypropylene film protective tape, comprising the following steps: adding butyl acrylate, isooctyl acrylate, methyl methacrylate, acrylic acid, hydroxyethyl methacrylate, functional monomers, solvent, and 20 wt% of the total amount of initiator to a reaction vessel, using a one-pot method, initiating the reaction at 85°C, adjusting the temperature to 80°C after initiation, starting to add the remaining initiator dropwise, completing the dropwise addition in 3 hours, continuing the reaction for another 3 hours to obtain adhesive, mixing the adhesive and curing agent and coating it onto the surface of a substrate, and curing to form an adhesive layer with a thickness of 25 μm on the surface of the substrate.

[0035] Performance testing

[0036] 1. Peel strength: Referring to GB / T 2792-2014, the 180° peel strength of the protective tapes provided in the examples and comparative examples with stainless steel plates was tested, and the results are shown in Table 2.

[0037] 2. Initial tack: The initial tack of the protective tapes provided in the examples and comparative examples was tested according to GB / T 4852-2002-Method A. The results are shown in Table 2.

[0038] 3. Holding power: The holding power of the protective tapes provided in the examples and comparative examples was tested according to GB / T 4851-2014-Method A. The results are shown in Table 2.

[0039] 4. Tensile strength: Refer to GB / T 1040.3-2006, dumbbell-shaped specimen: take the cured adhesive film (0.2 mm thick), stretch it at a speed of 500 mm / min until it breaks. The tensile strength results of the protective tapes provided in the examples and comparative examples are shown in Table 2.

[0040] 5. Removability: The protective tapes provided in the examples and comparative examples were used to bond PP, PE, ABS, stainless steel plates, glass plates, and painted plates. If no adhesive residue was left on the surface of each substrate after removal, the removability was rated as "excellent". The results are shown in Table 2.

[0041] Table 2

[0042]

[0043]

[0044] Analysis of the data in Table 2 of the examples and comparative examples shows that the products provided in Examples 1-3 have superior peel strength, initial tack, holding power, tensile strength and removability compared to those in Comparative Examples 1-3.

Claims

1. A uniaxially oriented polypropylene film protective tape, characterized in that, It includes a substrate layer and an adhesive layer; by weight, the adhesive layer includes at least the following raw materials: 8-20 parts butyl acrylate, 12-32 parts isooctyl acrylate, 4-14 parts methyl methacrylate, 1-7 parts acrylic acid, 1-6 parts hydroxyethyl methacrylate, 1-6 parts functional monomer, 40-60 parts solvent, 0.3-2 parts initiator, and 0.8-2 parts curing agent.

2. The uniaxially oriented polypropylene film protective tape according to claim 1, characterized in that, The solvent is selected from at least one of ester solvents or ketone solvents.

3. The uniaxially oriented polypropylene film protective tape according to claim 2, characterized in that, The ester solvent is selected from at least one of ethyl acetate, n-propyl acetate, isopropyl acetate, or butyl acetate.

4. The uniaxially oriented polypropylene film protective tape according to claim 2, characterized in that, The ketone solvent is selected from at least one of acetone, methyl ethyl ketone, or methyl isobutyl ketone.

5. The uniaxially oriented polypropylene film protective tape according to claim 1, characterized in that, The initiator is selected from at least one of peroxide initiators or azo initiators.

6. The uniaxially oriented polypropylene film protective tape according to claim 5, characterized in that, The peroxide initiator is selected from at least one of benzoyl peroxide, lauroyl peroxide, or peroxide dicarbonate.

7. The uniaxially oriented polypropylene film protective tape according to claim 5, characterized in that, The azo initiator is selected from at least one of azobisisobutyronitrile or azobisisoheptanenitrile.

8. The uniaxially oriented polypropylene film protective tape according to claim 1, characterized in that, The curing agent is selected from at least one of isocyanates, epoxy resins, or aluminum acetylacetonate.

9. The uniaxially oriented polypropylene film protective tape according to claim 1, characterized in that, The thickness of the adhesive layer is 20-30 μm.

10. A method for preparing a uniaxially oriented polypropylene film protective tape according to any one of claims 1-9, characterized in that, The process includes at least the following steps: adding butyl acrylate, isooctyl acrylate, methyl methacrylate, acrylic acid, hydroxyethyl methacrylate, functional monomers, solvent, and 20-40 wt% of the total amount of initiator to a reaction vessel, using a one-pot method, initiating the reaction at 80-90℃, adjusting the temperature to 75-85℃ after initiation, starting to add the remaining initiator dropwise, completing the dropwise addition in 3-4 hours, continuing the reaction for another 3-4 hours to obtain adhesive, mixing the adhesive with a curing agent and coating it onto the surface of the substrate, and forming an adhesive layer on the surface of the substrate after curing.

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