High-temperature-resistant high-toughness organic silicon modified peelable blue gel and preparation method thereof

Abstract

The invention discloses high-temperature-resistant and high-toughness organic silicon modified peelable blue gel and a preparation method thereof.The preparation method comprises the steps that firstly, polyorganosilicone polyol used for high-temperature-resistant polyurethane synthesis reacts with diisocyanate, and a prepolymer is formed; then carrying out an end-capping reaction by using an acrylate double-bond end-capping reagent to generate an organic silicon modified polyurethane acrylate prepolymer; and finally, adding a photoinitiator, an inorganic filler, an acrylate monomer and other auxiliaries to prepare the peelable blue gel with excellent comprehensive performance. The method provided by the invention solves the problems of insufficient toughness, peeling residue and the like of the existing peelable blue glue, and the prepared adhesive has excellent flexibility, high elongation at break, low peeling strength and no residue after peeling after UV curing, has heat resistance as high as 260 DEG C, and does not have residual glue within 10 minutes. The coating is especially suitable for protecting the surface of a material in a high-temperature scene, and has very high application value in specific application occasions.

Description

Technical Field

[0001] The invention belongs to the technical field of adhesives, and in particular relates to a method for preparing a high-temperature-resistant and high-toughness organosilicon-modified peelable blue adhesive. Background Art

[0002] In many industrial fields, especially when high-temperature operations are involved, the protection and use of materials are very strict. Traditional adhesives may fail or leave residue under high temperature conditions, so an adhesive with high temperature tolerance and high toughness is needed to meet these requirements. Silicone-modified adhesives are resistant to high temperatures and have no residue, and are widely used in the protection and bonding of materials in high-temperature environments. Its high-temperature resistance mainly comes from the introduction of silicone compounds such as siloxane polyols, which enables the adhesive to maintain good adhesion and strength under high temperature conditions. In addition, silicone-modified adhesives also have good flexibility and elongation at break, and will not leave residue after peeling, which has a very high applicability value for materials that require protection in high-temperature environments.

[0003] In the prior art, there is a close relationship between R value and toughness in the synthesis process of polyurethane acrylate (PUA). R value usually refers to the molar ratio of isocyanate to polyol in polyurethane, which has an important influence on the performance of polyurethane. Polyols with higher molecular weight usually increase the toughness of polyurethane because they can form more crosslinking points and segments, enhancing the elasticity and impact resistance of the material. The appropriate R value can balance hardness and toughness, so that the polyurethane has both a certain hardness and sufficient toughness to withstand impact and deformation in the application. Therefore, in the synthesis of polyurethane acrylate, the toughness of the material can be controlled to a certain extent by adjusting the R value. Comprehensively considering the effects of polyol type, isocyanate type and R value, the optimization and adjustment of polyurethane toughness can be achieved. Therefore, to obtain a polyurethane acrylate removable tape with excellent flexibility and high elongation at break, low peel strength and no residue after peeling, and heat resistance, the formula ratio needs to be comprehensively considered. Summary of the invention

[0004] In view of the technical problems existing in the prior art, the purpose of the present invention is to provide a high-temperature resistant and high-toughness organosilicon-modified peelable blue glue and a preparation method thereof. The present invention introduces organosilicon compounds such as organosilicon polyols into polyurethane acrylate adhesives, selects a suitable R value, combines photoinitiators, inorganic fillers and other additives, and prepares a peelable polyurethane acrylate adhesive with excellent comprehensive performance, which solves the problems of tolerance and peeling residue of existing peelable blue glues in high temperature environments, and provides a new solution for protecting the surface of materials in high temperature scenarios.

[0005] The purpose of the present invention is achieved through the following technical solutions: A method for preparing a high-temperature resistant and high-toughness organosilicon-modified peelable blue glue comprises the following steps: Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add polysilicone polyol to the reaction kettle, then add diisocyanate according to the appropriate R value, raise the temperature to 40-70 degrees Celsius and maintain the temperature for 2-4 hours to form a prepolymer. Add the acrylate double bond capping agent to the prepolymer, control the temperature at 50-70 degrees Celsius for a capping reaction for 0.5-3 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0006] The role of the acrylate double bond capping agent is to improve or impart specific properties to the material by introducing acrylate functional groups at the ends of the molecular chains.

[0007] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer (acrylate monomer acts as an initiator for the curing reaction, increases the crosslinking density and acts as a diluent) and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer in the following mass fractions: polyurethane acrylate prepolymer 30-60wt%, photoinitiator 0.01-1wt%, inorganic filler 5-40wt%, acrylate monomer 5-40wt%, other additives 0.1-5wt%. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high-temperature resistant and high-toughness silicone-modified peelable blue glue into a sealed and light-proof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage.

[0008] Furthermore, the diisocyanate mentioned above is an aliphatic isocyanate, such as one or more of isophorone diisocyanate (IPDI), 1,6-hexamethylene diisocyanate (HDI), hydrogenated toluene diisocyanate (H12MDI), cyclohexyl diisocyanate (CHDI), and 1,3-bis(isocyanatomethyl)cyclohexane (BIC).

[0009] Furthermore, the polysilicone polyol mentioned above is one or more of hydroxy-terminated polydimethylsiloxane (OH-PDMS), polydimethylsiloxane (PDMS) polyol, polytrimethylsiloxane (PTMS) polyol, and polysiloxane-polyether block copolymer.

[0010] Furthermore, the molecular weight of the polysilicone polyol described above is 1000-10000 g / mol. The isocyanate index R value (i.e. the molar ratio of cyanate groups to hydroxyl groups in the polysilicone polyol) used in synthesizing the prepolymer is between 1.05-1.35.

[0011] Furthermore, after the reaction at 40-70 degrees Celsius for 2-4 hours in step 1, the remaining unreacted cyanate groups react with the acrylate double bond capping agent in a molar ratio of 1:0.9-1.05, preferably in a molar ratio of 1:1. The amount of the remaining unreacted cyanate groups of the diisocyanate is the amount of the portion of the molar ratio between the cyanate groups of the diisocyanate and the hydroxyl groups of the polysilicone polyol that exceeds 1:1.

[0012] Furthermore, the above-mentioned acrylate double bond capping agent is hydroxyethyl acrylate (HEA), hydroxypropyl acrylate (HPA), hydroxyethyl methacrylate (HEMA) or hydroxypropyl methacrylate (HPMA).

[0013] Furthermore, the inorganic filler mentioned above is one or more of nano silicon dioxide, nano titanium dioxide or nano aluminum oxide, zinc oxide powder, calcium silicate powder, aluminum hydroxide powder, and magnesium silicate powder.

[0014] Furthermore, the acrylic acid ester monomer mentioned above is at least one of methyl methacrylate, butyl methacrylate and ethyl acrylate.

[0015] Compared with the prior art, the advantages of the present invention are: simple process, low pollution and energy consumption, and easy-to-obtain raw materials. The prepared silicone-modified peelable blue glue not only has excellent flexibility and high elongation at break after UV curing, but also has low peel strength and no residue after peeling, and heat resistance up to 260 degrees Celsius, and no residual glue within 10 minutes. It is particularly suitable for protecting the surface of materials in high temperature scenes, and has high application value in specific application occasions. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the infrared spectrum of the prepolymer obtained in step 1 of Example 2 of the present invention. DETAILED DESCRIPTION

[0017] The present invention will be further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0018] In the embodiment of the present invention, the blue color paste is 6153-UV, and the leveling agent is BYK-UV3510 produced by German BYK.

[0019] In the embodiment of the present invention, the R value is the molar ratio of the cyanate group in the diisocyanate to the hydroxyl group in the polysilicone polyol.

[0020] The hydroxy-terminated polydimethylsiloxane (OH-PDMS) and polydimethylsiloxane (PDMS) polyol used in the embodiments of the present invention both contain 2 mol of hydroxyl groups per 1 mol molecular weight.

[0021] In the embodiments of the present invention, hydroxy-terminated polydimethylsiloxane OH-PDMS and polydimethylsiloxane (PDMS) polyol were purchased from Shenzhen Jipeng Silicon Fluoride Materials Co., Ltd. and Shenzhen Sicheng Silicone Co., Ltd., respectively.

[0022] Example 1 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add hydroxy-terminated polydimethylsiloxane (OH-PDMS) with a molecular weight of 2000:300g into the reactor, then add 35g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.05, raise the temperature to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 1.8g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for a capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0023] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 1g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 200g of nano-silica, 200g of methyl methacrylate (MMA), 8g of blue color paste and 2g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high-temperature resistant and high-toughness organosilicon-modified peelable blue glue into a sealed and light-proof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes.

[0024] Example 2 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add 308g of polydimethylsiloxane (PDMS) polyol with a molecular weight of 2000 to the reactor, then add 38g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.11, heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 4g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for a capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0025] Step 2: Prepare adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 2g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 150g of zinc oxide powder, 150g of butyl methacrylate (BMA), 6.4g of blue color paste and 1.6g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high temperature resistant and high toughness silicone modified peelable blue glue into a sealed and lightproof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes.

[0026] Example 3 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add hydroxy-terminated polydimethylsiloxane (OH-PDMS) with a molecular weight of 1000: 275g to the reactor, then add 68g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.11, heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 7.2g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for a capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0027] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 2g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 50g of nano-silica, 250g of ethyl acrylate (EA), 9.6g of blue color paste and 2.4g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high-temperature resistant and high-toughness silicone-modified peelable blue glue into a sealed and light-proof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes. Example 4 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add hydroxy-terminated polydimethylsiloxane (OH-PDMS) with a molecular weight of 1000:268g to the reactor, then add 74g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.24, and heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 15.2g of hydroxyethyl methacrylate (HEMA) to the prepolymer, control the temperature at 60 degrees Celsius for a capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0028] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 1g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 150g of nano-silica, 150g of ethyl acrylate (EA), 9.6g of blue color paste and 2.4g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high-temperature resistant and high-toughness organosilicon-modified peelable blue glue into a sealed and light-proof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes. Example 5 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add 317g of polydimethylsiloxane (PDMS) polyol with a molecular weight of 3000 to the reactor, then add 29g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.23, and heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 5.8g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for end-capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0029] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 2g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 100g of nano-silica, 200g of methyl methacrylate (MMA), 8g of blue color paste and 2g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high-temperature resistant and high-toughness organosilicon-modified peelable blue glue into a sealed and light-proof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes.

[0030] Example 6 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add 317g of hydroxy-terminated polydimethylsiloxane (OH-PDMS) with a molecular weight of 3000 to the reactor, then add 29g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.23, and heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 5.8g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for a capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0031] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 2g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 100g of nano titanium dioxide, 200g of methyl methacrylate (MMA), 8g of blue color paste and 2g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high-temperature resistant and high-toughness organosilicon-modified peelable blue glue into a sealed and light-proof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes.

[0032] Example 7 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add 315g of polydimethylsiloxane (PDMS) polyol with a molecular weight of 3000 to the reactor, then add 31g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.33, and heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 8g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for end-capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0033] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 1g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 100g of nano-silica, 200g of methyl methacrylate (MMA), 8g of blue color paste and 2g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high-temperature resistant and high-toughness organosilicon-modified peelable blue glue into a sealed and light-proof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes.

[0034] Examples 1, 2, 5, and 6 are cases with better effects. Due to different raw materials and proportions, the corresponding tape performance varies according to different application occasions. The infrared spectrum of the prepolymer in Example 2 is shown in FIG. Figure 1 As shown, the functional groups above are shown to contain Si-O bonds and polyurethane bonds.

[0035] Comparative Example 1 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add polydimethylsiloxane (PDMS) polyol with a molecular weight of 2000:301g to the reactor, then add 44.5g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.33, and heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 11.5g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for a capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0036] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 2g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 150g of zinc oxide powder, 150g of butyl methacrylate (BMA), 6.4g of blue color paste and 1.6g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high temperature resistant and high toughness silicone modified peelable blue glue into a sealed and lightproof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes.

[0037] Comparative Example 2 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add 308g of polydimethylsiloxane (PDMS) polyol with a molecular weight of 2000 to the reactor, then add 38g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.11, heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 4g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for a capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0038] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 2g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 150g of zinc oxide powder, 150g of hydroxyethyl acrylate (HEA), 6.4g of blue color paste and 1.6g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high temperature resistant and high toughness silicone modified peelable blue glue into a sealed and lightproof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes.

[0039] Comparative Example 3 Step 1: Preparation of polyurethane acrylate adhesive prepolymer Add 328g of polydimethylsiloxane (PDMS) polyol with a molecular weight of 2000 to the reactor, then add 38g of isophorone diisocyanate (IPDI), that is, the isocyanate index R value used when synthesizing the prepolymer is 1.04, and heat to 60 degrees Celsius and maintain the temperature for 3 hours to form a prepolymer. Add 1.61g of hydroxyethyl acrylate (HEA) to the prepolymer, control the temperature at 60 degrees Celsius for a capping reaction for 2 hours to generate a silicone-modified polyurethane acrylate prepolymer.

[0040] Step 2: Prepare the adhesive Add photoinitiator, inorganic filler, acrylate monomer and other additives (such as color paste, leveling agent, etc.) to the obtained polyurethane acrylate prepolymer according to the following mass: 300g of polyurethane acrylate prepolymer obtained in step 1, 2g of photoinitiator (2,4,6-trimethylbenzoyl) diphenylphosphine oxide (TPO), 150g of zinc oxide powder, 150g of butyl methacrylate (BMA), 6.4g of blue color paste and 1.6g of leveling agent. Mix the above raw materials evenly to ensure that the inorganic filler is evenly dispersed in the adhesive. Put the prepared high temperature resistant and high toughness silicone modified peelable blue glue into a sealed and lightproof syringe and seal it to prevent the adhesive from being contaminated or deteriorating during storage. When in use, apply the adhesive on the surface to be protected (a 2.5cm wide and 3mm thick strip), cure it with a UV curing device to ensure that the adhesive is completely cured and attached to the surface, remove the strip for a tensile fracture strain test, and at the same time stick the strip on a stainless steel plate for a high-temperature residual adhesive test at 260 degrees Celsius for ten minutes.

[0041] Compared with Example 2, Comparative Example 1 has a higher isocyanate index R value, an excessive amount of end-capping agent HEA, and excessive cross-linking will make the molecular chain rigid, reduce flexibility and elongation at break, and cause the adhesive to lose its good elastic deformation ability. As shown in Table 1, the fracture strain value of the resulting tape is significantly reduced.

[0042] Compared with Example 2, the type of diluent was changed, the peel strength was increased, and residual glue appeared because the hydroxyl groups on HEA can have a stronger force on the bonding surface.

[0043] Compared with Example 2, Comparative Example 3 increases the amount of polydimethylsiloxane (PDMS) polyol, resulting in excessive polydimethylsiloxane (PDMS) polyol, too low R value, incomplete reaction, and a significantly decreased breaking strain value of the resulting tape, increased peel strength, and residual adhesive at high temperature.

[0044] Table 1 Performance test results of silicone modified peelable blue glue in different embodiments and comparative examples .

[0045] While achieving peelability without residual adhesive, the formula of the present invention explores the influence of other factors such as R value on fracture strain, limits the R value range of 1.05-1.35 when synthesizing the prepolymer, comprehensively considers the properties such as fracture strain value, peel strength, residual adhesive, and obtains a high-temperature resistant and high-toughness peelable blue adhesive.

[0046] The above description is only part of the embodiments of the present invention and is not intended to limit the present invention. All equivalent changes and modifications made according to the content of the present invention are within the protection scope of the present invention.

Claims

1. A method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue, characterized in that: The following steps are involved: Step 1: Mix and stir polysilicone polyol and diisocyanate to react at a temperature of 40-70°C for 2-4 hours to form a prepolymer; Step 2: Adding an acrylate double bond capping agent to the prepolymer obtained in step 1 to carry out a capping reaction at 50-70° C. for 0.5-3 hours to generate a polyurethane acrylate prepolymer; Step 3: Add photoinitiator, inorganic filler, acrylate monomer and other additives to the prepolymer in step 2, mix evenly to obtain adhesive, and seal it in a can.

2. The method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue as claimed in claim 1, characterized in that: The diisocyanate is an aliphatic isocyanate selected from isophorone diisocyanate IPDI, 1,6-hexamethylene diisocyanate HDI, hydrogenated toluene diisocyanate H 12 One or more of MDI, cyclohexyl diisocyanate CHDI, and 1,3-bis(isocyanatomethyl)cyclohexane BIC.

3. The method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue as claimed in claim 1, characterized in that: The polysilicone polyol is one or more of hydroxy-terminated polydimethylsiloxane OH-PDMS, polydimethylsiloxane (PDMS) polyol, polytrimethylsiloxane (PTMS) polyol, and polysiloxane-polyether block copolymer.

4. The method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue as claimed in claim 1, characterized in that: The molecular weight of the polysilicone polyol is 1000-10000 g / mol; the isocyanate index R value used in the synthesis of the prepolymer in step 1 is between 1.05-1.35, and the R value is the molar ratio of the cyanate group in the diisocyanate to the hydroxyl group in the polysilicone polyol; In step 2, the molar ratio of the remaining unreacted cyanate groups of the diisocyanate to the acrylate double bond capping agent is 1:0.9-1.

05.

5. The method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue as claimed in claim 1, characterized in that: The acrylate double bond capping agent in step 2) is hydroxyethyl acrylate HEA, hydroxypropyl acrylate HPA, hydroxyethyl methacrylate HEMA or hydroxypropyl methacrylate HPMA.

6. The method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue as claimed in claim 1, characterized in that: The adhesive in step 3) comprises the following raw materials in mass fraction: 30-60wt% polyurethane acrylate prepolymer, 0.01-1wt% photoinitiator, 5-40wt% inorganic filler, 5-40wt% acrylate monomer, and 0.1-5wt% other additives; the other additives include one or two of color paste and leveling agent.

7. The method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue as claimed in claim 6, characterized in that: The adhesive in step 3) comprises the following raw materials in weight fraction: 42-50wt% of polyurethane acrylate prepolymer, 0.1-0.35wt% of photoinitiator, 15-28wt% of inorganic filler, 24.5-40wt% of acrylate monomer, and 1.3-1.9wt% of other additives.

8. The method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue as claimed in claim 1, characterized in that: The inorganic filler is one or more of nano silicon dioxide, nano titanium dioxide, nano aluminum oxide, zinc oxide powder, calcium silicate powder, aluminum hydroxide powder, and magnesium silicate powder.

9. The method for preparing a high temperature resistant and high toughness organosilicon modified peelable blue glue as claimed in claim 1, characterized in that: In step 3), the acrylate monomer is at least one of methyl methacrylate, butyl methacrylate and ethyl acrylate.

10. A high temperature resistant and high toughness organosilicon modified peelable blue glue prepared by the method as described in any one of claims 1 to 9.

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