A hot melt adhesive with high bonding strength and its application in silicone and nylon composite fabric

Abstract

The present application relates to the technical field of polyurethane hot melt adhesives, in particular to a hot melt adhesive with high bonding strength and its application in silicone and nylon composite fabrics. A hot melt adhesive with high bonding strength is mainly made of the following raw materials in parts by mass: 10-20 parts of high-activity NCO-terminated isocyanate prepolymer A, 10-20 parts of low-activity NCO-terminated isocyanate prepolymer B, 5-10 parts of primary amine-terminated isocyanate prepolymer A, 5-10 parts of primary hydroxyl-terminated isocyanate prepolymer B, 5-20 parts of thermoplastic EVA resin, 1-5 parts of organic polysilazane, 0.5-2 parts of cross-linking agent, 0.5-2 parts of coupling agent, 0.5-2 parts of antioxidant, 0.5-2 parts of anti-ultraviolet agent, 0.05-0.5 parts of catalyst, 4-8 parts of gas phase silica, and 1-3 parts of defoamer. The bonding strength of the present application is excellent and has relatively good bonding strength and bonding stability to nylon PA substrate.

Description

Technical Field

[0001] The present application relates to the technical field of polyurethane hot melt adhesives, and in particular to a hot melt adhesive with high bonding strength and its application in silicone and nylon composite fabrics. Background Art

[0002] Hot melt adhesive is solid at room temperature. After heating it to a flowable molten state, it can be coated or rolled on the surface of the adherend. After the adherend is pressed and air-cooled, the hot melt adhesive solidifies to generate cohesion and stably adhere the two. Polyurethane hot melt adhesive has the advantages of low pollution, high initial viscosity and fast adhesion, and is widely used in modern automated assembly industry.

[0003] Polyurethane hot melt adhesives are mainly divided into low-melting-point thermoplastic elastic TPU hot melt adhesives and reactive polyurethane hot melt adhesives. Low-melting-point thermoplastic elastic TPU hot melt adhesives are suitable for low-temperature environments and adherend substrates with low heat sensitivity. Reactive polyurethane hot melt adhesives have relatively good temperature resistance and can be applied to heat-sensitive adherends. The active groups introduced into their molecular chain structure can further react to achieve cross-linking and curing to form a thermosetting resin form with a three-dimensional network structure, which can improve the bonding strength while improving heat resistance and creep resistance, effectively expanding its scope of use, and can be applied to non-metallic substrates such as PC, ABS, and TPU. However, its bonding strength and bonding stability to nylon PA substrates are relatively weak, which limits its development and application in the field of nylon composite fabrics. To this end, the present application provides a hot melt adhesive with high bonding strength and its application in silicone and nylon composite fabrics. Summary of the invention

[0004] In order to solve the technical problem that the existing reactive polyurethane hot melt adhesive has relatively weak bonding strength and bonding stability to nylon PA substrate, which limits its development and application in the field of nylon composite fabrics, this application independently developed a hot melt adhesive with high bonding strength, which has relatively good bonding strength and bonding stability to nylon PA substrate. It can be used as an adhesive to bond and fix silicone to nylon composite fabric, which is suitable for the high bonding strength requirements of nylon composite fabrics for hot melt adhesives.

[0005] The hot melt adhesive with high bonding strength provided in the present application is realized by the following technical solutions:

[0006] A hot melt adhesive with high bonding strength is mainly made of the following raw materials in parts by weight: 10-20 parts of high-activity-NCO-terminated isocyanate prepolymer A, 10-20 parts of low-activity-NCO-terminated isocyanate prepolymer B, 5-10 parts of primary amine-terminated isocyanate prepolymer A, 5-10 parts of primary hydroxyl-terminated isocyanate prepolymer B, 5-20 parts of thermoplastic EVA resin, 1-5 parts of organic polysilazane MY 9150, 0.5-2 parts of a cross-linking agent, 0.5-2 parts of a coupling agent, 0.5-2 parts of an antioxidant, 0.5-2 parts of an anti-ultraviolet agent, 0.05-0.5 parts of a catalyst, 4-8 parts of fumed silica, and 1-3 parts of a defoaming agent; the total molar amount of -NCO in the high-activity -NCO-terminated isocyanate prepolymer A and the low-activity -NCO-terminated isocyanate prepolymer B is 0.5-2 times the total molar amount of the primary amine in the primary amine-terminated isocyanate prepolymer A and the primary hydroxyl in the primary hydroxyl-terminated isocyanate prepolymer B.

[0007] The highly active-NCO-terminated isocyanate prepolymer A in the present application first reacts with the primary amine-terminated isocyanate prepolymer A to form initial adhesion strength, and the low-active-NCO-terminated isocyanate prepolymer B and the primary hydroxyl-terminated isocyanate prepolymer B react subsequently. In the process in which the highly active-NCO-terminated isocyanate prepolymer A first reacts with the primary amine-terminated isocyanate prepolymer A, the low-active-NCO-terminated isocyanate prepolymer B and the primary hydroxyl-terminated isocyanate prepolymer B can act as plasticizers, thereby overcoming the problem of environmental pollution caused by the addition of plasticizers, and at the same time allowing the hot melt adhesive as a whole to effectively penetrate the substrate. The surface effectively improves the bonding strength and bonding stability. After the subsequent primary amine-terminated isocyanate prepolymer A is consumed, the remaining part of the highly active-NCO-terminated isocyanate prepolymer A will preferentially react with the primary hydroxyl-terminated isocyanate prepolymer B, which is beneficial to improving the overall permeability and leveling properties while improving the overall processability. The remaining small part of the highly active-NCO-terminated isocyanate prepolymer A and most of the low-active-NCO-terminated isocyanate prepolymer B will react with part of the moisture in the air and / or cross-link under ultraviolet light to form a three-dimensional network structure, achieving excellent bonding strength and bonding stability. The organic polysilazane MY 9150 reacts with moisture in the air to hydrolyze to produce amino or silanol groups, and the remaining small part of the highly active-NCO-terminated isocyanate prepolymer A and most of the low-active-NCO-terminated isocyanate prepolymer B will undergo chain extension and cross-linking reactions with it to achieve curing, reducing the release of carbon dioxide gas and reducing the probability of bubbles and bubbling in the adhesive layer, which can further improve the overall bonding strength and bonding stability of the hot melt adhesive. In summary, the bonding strength of the present application is excellent and has relatively good bonding strength and bonding stability to the nylon PA substrate.

[0008] Preferably, the highly active-NCO-terminated isocyanate prepolymer A comprises a polyol, bismuth carboxylate, DMF, an antioxidant 1010, m-xylylene diisocyanate, and a capping agent - diphenylmethane-4,4'-diisocyanate; the polyol is composed of a highly crystalline polyol and a dihydroxy-terminated silicone oil in a mass ratio of (8-9):(1-2); the dihydroxy-terminated silicone oil is at least one of a hydroxy-terminated methyl vinyl silicone oil, a double-terminated hydroxypropyl silicone oil, and a double-terminated alcohol hydroxyl long-chain alkyl silicone oil; the highly crystalline polyol is at least one of polyadipate-1,6-hexanediol ester diol and polysebacate 1,6-hexanediol ester diol with a molecular weight of 1000 to 4000 g / mol; the mass of the capping agent in the highly active-NCO-terminated isocyanate prepolymer A accounts for 5-20% of the highly active-NCO-terminated isocyanate prepolymer A.

[0009] Preferably, the low-reactive-NCO-terminated isocyanate prepolymer B comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, m-xylylene diisocyanate, and a capping agent - isophorone diisocyanate; the polyol is composed of a low-crystalline polyol and a dihydroxy-terminated silicone oil in a mass ratio of (8-9):(1-2); the dihydroxy-terminated silicone oil is at least one of a hydroxy-terminated methyl vinyl silicone oil, a double-terminated hydroxypropyl silicone oil, and a double-terminated alcohol hydroxyl long-chain alkyl silicone oil; the low-crystalline polyol is a low-crystalline linear polyester polyol PLOS-ZY1200 with a molecular weight of 2200 or a low-crystalline dimer acid polyester polyol PLOS-ZY2250 with a molecular weight of 2500; the mass of the capping agent in the low-reactive-NCO-terminated isocyanate prepolymer B accounts for 5-20% of the total amount of the low-reactive-NCO-terminated isocyanate prepolymer B.

[0010] Preferably, the primary amine-terminated isocyanate prepolymer A comprises a polyol, bismuth carboxylate, DMF, an antioxidant 1010, diphenylmethane-4,4'-diisocyanate, and a capping agent -1,6-hexanediamine; the polyol is a highly crystalline polyol, a polyether diol, and a polycarbonate diol in a mass ratio of (6-8):(1-2):(1-2); the highly crystalline polyol is at least one of poly(1,6-hexanediol adipate) diol and poly(1,6-hexanediol sebacate) diol having a molecular weight of 1000 to 4000 g / mol; the mass of the primary amine in the primary amine-terminated isocyanate prepolymer A accounts for 0.5-2% of the total amount of the primary amine-terminated isocyanate prepolymer A.

[0011] Preferably, the primary hydroxyl-terminated isocyanate prepolymer B comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, isophorone diisocyanate, and a capping agent - bisphenol A dihydroxyethyl ether; the polyol is a low-crystalline polyol combined with at least one of hydroxyl-terminated methyl vinyl silicone oil, polyether diol, and polycarbonate diol; the low-crystalline polyol is a low-crystalline linear polyester polyol PLOS-ZY1200 with a molecular weight of 2200 or a low-crystalline dimer acid polyester polyol PLOS-ZY2250 with a molecular weight of 2500; the mass of primary hydroxyl groups in the primary hydroxyl-terminated isocyanate prepolymer B accounts for 0.5-2% of the total amount of the primary hydroxyl-terminated isocyanate prepolymer B.

[0012] Preferably, the method for preparing the hot melt adhesive with high bonding strength comprises the following steps:

[0013] Step 1: Preparation of highly active -NCO-terminated isocyanate prepolymer A: The polyol is heated to 100-110°C and dehydrated under vacuum conditions for 1-4 hours. The obtained polyol is mixed evenly with bismuth carboxylate, DMF, antioxidant 1010, and m-xylylene diisocyanate, and then heated to 65-70°C to react until the system viscosity is 3000-12000mPa·s / 25°C, and then a blocking agent - diphenylmethane-4,4'-diisocyanate is added, and the reaction is carried out at 80-85°C for 0.5-2h to obtain an isocyanate prepolymer A with an -NCO content of 5-20wt%;

[0014] Preparation of low-activity -NCO-terminated isocyanate prepolymer B: heating the polyol to 100-110°C and dehydrating under vacuum for 1-4h, mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010, and m-xylylene diisocyanate, heating to 65-70°C and reacting until the system viscosity is 3000-12000mPa·s / 25°C, adding the blocking agent - isophorone diisocyanate, reacting at 90-95°C for 0.5-2h, and obtaining an isocyanate prepolymer B with an -NCO content of 5-20wt%;

[0015] Preparation of primary amine-terminated isocyanate prepolymer A: heating a polyol to 100-110° C. and dehydrating it under vacuum for 1-4 hours, uniformly mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010, and diphenylmethane-4,4'-diisocyanate, heating the mixture to 65-70° C. and reacting the mixture until the system viscosity reaches 3000-12000 mPa·s / 25° C., adding a capping agent - 1,6-hexanediamine, and reacting the mixture at 75-85° C. for 0.5-2 hours, thereby obtaining a primary amine-terminated isocyanate prepolymer A having a primary amine group content of 0.5-2 wt%;

[0016] Preparation of primary hydroxyl terminated isocyanate prepolymer B: heating a polyol to 100-110° C. and dehydrating under vacuum for 1-4 h, uniformly mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010 and isophorone diisocyanate, heating the mixture to 75-80° C. and reacting until the system viscosity reaches 3000-12000 mPa·s / 25° C., adding a capping agent, bisphenol A dihydroxyethyl ether, and reacting the mixture at 90-95° C. for 0.5-2 h, thereby obtaining a primary hydroxyl terminated isocyanate prepolymer B having a primary hydroxyl content of 0.5-2 wt%;

[0017] Step 2: Mix the high-activity NCO-terminated isocyanate prepolymer A, the low-activity NCO-terminated isocyanate prepolymer B, the primary amine-terminated isocyanate prepolymer A, and the primary hydroxyl-terminated isocyanate prepolymer B in step 1 under nitrogen protection, add 5-20 parts of thermoplastic EVA resin, 1-5 parts of organic polysilazane MY 9150, a crosslinking agent, a coupling agent, an antioxidant, an anti-ultraviolet agent, a catalyst, fumed silica, and a defoaming agent, heat to 98-100° C., stir for 30-45 minutes under vacuum at -0.09 to -0.08 MPa, and after vacuum degassing, cool to room temperature and package in a black sealed bag.

[0018] The dihydroxy-terminated silicone oil introduced into the molecular chain segments of the high-activity NCO-terminated isocyanate prepolymer A and the low-activity NCO-terminated isocyanate prepolymer B of the present application contains Si-O bonds with polarity similar to that of the Si-O bonds in the silica gel structure, so that the high-activity NCO-terminated isocyanate prepolymer A has good interfacial compatibility with the silica gel substrate, and has a certain initial adhesion strength with the silica gel interface. After the low-activity NCO-terminated isocyanate prepolymer B is finally cross-linked and cured, the formed hot-melt adhesive layer can have good bonding strength with the silica gel, which can meet the bonding and composite use requirements of the silica gel and nylon composite cloth.

[0019] The preparation method provided in this application is relatively simple, which facilitates mass production and reduces overall production costs.

[0020] Preferably, the crosslinking agent is at least one of trimethylolpropane triacrylate, pentaerythritol triacrylate, and tris(2-hydroxyethyl)isocyanuric acid triacrylate.

[0021] Preferably, the coupling agent is at least one of γ-glycidyloxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane and 3-isocyanatepropyltriethoxysilane.

[0022] Preferably, the antioxidant is at least one of antioxidant 1010, antioxidant 1098, and antioxidant BHT combined with antioxidant 168; the anti-ultraviolet agent is at least one of UV-531, UV-326, UV-320, and UV-622.

[0023] Preferably, the catalyst is at least one of stannous octoate, bismuth carboxylate, and bismorpholine diethyl ether; and the defoamer is at least one of BASF Efka 2720, Efka 2723, and Evonik TEGO Airex 963.

[0024] The application of the high bonding strength hot melt adhesive prepared in the present application in silicone and nylon composite cloth is specifically applied to the field of nylon composite cloth fabric bonding, and the silicone surface layer and the nylon composite cloth are bonded and fixed by the high bonding strength hot melt adhesive.

[0025] In summary, this application has the following advantages:

[0026] 1. The bonding strength of the present application is excellent and has relatively good bonding strength and bonding stability to the nylon PA substrate. It is used in the field of nylon composite fabric bonding. The silicone surface layer is bonded and fixed to the nylon composite fabric by a hot melt adhesive with high bonding strength.

[0027] 2. The preparation method provided in this application is relatively simple, which facilitates mass production and reduces overall production costs. DETAILED DESCRIPTION

[0028] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples.

[0029] Example

[0030] A hot melt adhesive with high bonding strength is mainly made of the following raw materials in parts by mass: 10-20 parts of -NCO-terminated isocyanate prepolymer A, 10-20 parts of -NCO-terminated isocyanate prepolymer B, 5-10 parts of primary amine-terminated isocyanate prepolymer A, 5-10 parts of primary hydroxyl-terminated isocyanate prepolymer B, 5-20 parts of thermoplastic EVA resin, 1-5 parts of organic polysilazane MY 9150, 0.5-2 parts of cross-linking agent, 0.5-2 parts of coupling agent, 0.5-2 parts of antioxidant, 0.5-2 parts of anti-ultraviolet agent, 0.05-0.5 parts of catalyst, 4-8 parts of fumed silica, and 1-3 parts of defoaming agent. The hot melt adhesive with high bonding strength prepared in the present application is applied to the bonding field of nylon composite fabrics, and the silicone surface layer is bonded and fixed to the nylon composite fabric by the hot melt adhesive with high bonding strength.

[0031] The crosslinking agent is at least one of trimethylolpropane triacrylate, pentaerythritol triacrylate, and tris(2-hydroxyethyl)isocyanuric acid triacrylate.

[0032] The coupling agent is at least one of γ-glycidyloxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane and 3-isocyanatepropyltriethoxysilane.

[0033] The antioxidant is composed of at least one of antioxidant 1010, antioxidant 1098, and antioxidant BHT and antioxidant 168;

[0034] The anti-ultraviolet agent is at least one of UV-531, UV-326, UV-320, and UV-622.

[0035] The catalyst is at least one of stannous octoate, bismuth carboxylate and bismorpholine diethyl ether.

[0036] The defoaming agent is at least one of BASF Efka 2720, Efka 2723 and Evonik TEGO Airex 963.

[0037] The total molar amount of -NCO in the -NCO-terminated isocyanate prepolymer A and the -NCO-terminated isocyanate prepolymer B is 0.5-2 times the total molar amount of primary amine in the primary amine-terminated isocyanate prepolymer A and primary hydroxyl in the primary hydroxyl-terminated isocyanate prepolymer B. The reactive groups in the prepared hot melt adhesive with high bonding strength are high and low reactive -NCO groups and reactive groups contained in the crosslinking agent.

[0038] The highly active NCO-terminated isocyanate prepolymer A comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, m-xylylene diisocyanate and a capping agent, diphenylmethane-4,4'-diisocyanate. The mass of the capping agent in the highly active NCO-terminated isocyanate prepolymer A accounts for 5-20% of the highly active NCO-terminated isocyanate prepolymer A.

[0039] The polyol is composed of a high crystalline polyol and a dihydroxy-terminated silicone oil in a mass ratio of (8-9):(1-2). The dihydroxy-terminated silicone oil is at least one of hydroxy-terminated methyl vinyl silicone oil, dihydroxypropyl silicone oil, and dihydroxyl long-chain alkyl silicone oil. The high crystalline polyol is at least one of poly(1,6-hexanediol adipate) and poly(1,6-hexanediol sebacate) with a molecular weight of 1000 to 4000 g / mol.

[0040] The low-activity-NCO-terminated isocyanate prepolymer B comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, m-xylylene diisocyanate, and a capping agent, isophorone diisocyanate. The mass of the capping agent in the low-activity-NCO-terminated isocyanate prepolymer B accounts for 5-20% of the total amount of the low-activity-NCO-terminated isocyanate prepolymer B.

[0041] The polyol is composed of low-crystalline polyol and dihydroxy-terminated silicone oil in a mass ratio of (8-9):(1-2).

[0042] The dihydroxyl-terminated silicone oil is at least one of hydroxyl-terminated methyl vinyl silicone oil, double-terminated hydroxypropyl silicone oil, and double-terminated alcohol hydroxyl long-chain alkyl silicone oil. The low-crystalline polyol is a low-crystalline linear polyester polyol PLOS-ZY1200 with a molecular weight of 2200 or a low-crystalline dimer acid polyester polyol PLOS-ZY2250 with a molecular weight of 2500. The mass of the primary amine in the primary amine-terminated isocyanate prepolymer A accounts for 0.5-2% of the total amount of the primary amine-terminated isocyanate prepolymer A.

[0043] The primary amine-terminated isocyanate prepolymer A is prepared from polyol, bismuth carboxylate, DMF, antioxidant 1010, diphenylmethane-4,4'-diisocyanate, and end-capping agent-1,6-hexanediamine. The polyol is composed of highly crystalline polyol, polyether diol, and polycarbonate diol in a mass ratio of (6-8):(1-2):(1-2). The highly crystalline polyol is at least one of poly(1,6-hexanediol adipate) diol and poly(1,6-hexanediol sebacate) diol with a molecular weight of 1000 to 4000 g / mol.

[0044] The primary hydroxyl-terminated isocyanate prepolymer B comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, isophorone diisocyanate and end-capping agent-bisphenol A dihydroxyethyl ether. The mass of primary hydroxyl in the primary hydroxyl-terminated isocyanate prepolymer B accounts for 0.5-2% of the total amount of the primary hydroxyl-terminated isocyanate prepolymer B.

[0045] The polyol is composed of a low-crystalline polyol and at least one of hydroxyl-terminated methyl vinyl silicone oil, polyether diol, and polycarbonate diol. Preferably, the polyol is composed of a low-crystalline polyol, hydroxyl-terminated methyl vinyl silicone oil, and polyether diol in a mass ratio of (6-8):(0.5-1):(1-3).

[0046] The low crystalline polyol is a low crystalline linear polyester polyol PLOS-ZY1200 having a molecular weight of 2200 or a low crystalline dimer acid polyester polyol PLOS-ZY2250 having a molecular weight of 2500.

[0047] The method for preparing a hot melt adhesive with high bonding strength comprises the following steps:

[0048] Step 1: Preparation of highly active NCO-terminated isocyanate prepolymer A: heating the polyol to 100-110°C and dehydrating under vacuum for 1-4h, mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010, and m-xylylene diisocyanate, heating to 65-70°C and reacting until the system viscosity is 3000-12000mPa·s / 25°C, adding the blocking agent diphenylmethane-4,4'-diisocyanate, reacting at 80-85°C for 0.5-2h to obtain an isocyanate prepolymer A with an NCO content of 5-20wt%;

[0049] Preparation of low-activity -NCO-terminated isocyanate prepolymer B: heating the polyol to 100-110°C and dehydrating under vacuum for 1-4h, mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010, and m-xylylene diisocyanate, heating to 65-70°C and reacting until the system viscosity is 3000-12000mPa·s / 25°C, adding the blocking agent - isophorone diisocyanate, reacting at 90-95°C for 0.5-2h, and obtaining an isocyanate prepolymer B with an -NCO content of 5-20wt%;

[0050] Preparation of primary amine-terminated isocyanate prepolymer A: heating a polyol to 100-110° C. and dehydrating it under vacuum for 1-4 hours, uniformly mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010, and diphenylmethane-4,4'-diisocyanate, heating the mixture to 65-70° C. and reacting the mixture until the system viscosity reaches 3000-12000 mPa·s / 25° C., adding a capping agent - 1,6-hexanediamine, and reacting the mixture at 75-85° C. for 0.5-2 hours, thereby obtaining a primary amine-terminated isocyanate prepolymer A having a primary amine group content of 0.5-2 wt%;

[0051] Preparation of primary hydroxyl terminated isocyanate prepolymer B: heating a polyol to 100-110° C. and dehydrating under vacuum for 1-4 h, uniformly mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010 and isophorone diisocyanate, heating the mixture to 75-80° C. and reacting until the system viscosity reaches 3000-12000 mPa·s / 25° C., adding a capping agent, bisphenol A dihydroxyethyl ether, and reacting the mixture at 90-95° C. for 0.5-2 h, thereby obtaining a primary hydroxyl terminated isocyanate prepolymer B having a primary hydroxyl content of 0.5-2 wt%;

[0052] Step 2: Mix the high-activity NCO-terminated isocyanate prepolymer A, the low-activity NCO-terminated isocyanate prepolymer B, the primary amine-terminated isocyanate prepolymer A, and the primary hydroxyl-terminated isocyanate prepolymer B in step 1 under nitrogen protection, add a crosslinking agent, a coupling agent, an antioxidant, an anti-ultraviolet agent, a catalyst, fumed silica, and a defoaming agent, heat to 98-100° C., stir for 30-45 minutes under a vacuum of -0.09 to -0.08 MPa, and after vacuum degassing, cool to room temperature and package in a black sealed bag to obtain a hot melt adhesive with high bonding strength.

[0053] Example 1: A hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 8 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150 (Anhui Mingyi Silicon Industry Co., Ltd.), 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 5 parts of fumed silica (Wacker fumed silica N20, Germany), 2 parts of defoamer-BASF Efka 2720.

[0054] Highly active-NCO terminated isocyanate prepolymer A is made of 400 g of poly(1,6-hexanediol adipate) with a number average molecular weight of 2000 (customized by Zhejiang Hexin Technology Co., Ltd.), 71 g of double-terminal alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H (average molecular weight 3550, hydroxyl value 25.0 KOHmg / g), 0.5 g of bismuth carboxylate, 20 g of DMF, 0.8 g of antioxidant 1010, 38.3 g of m-xylylene diisocyanate, and 125.2 g of end-capping agent-diphenylmethane-4,4'-diisocyanate.

[0055] The preparation method of highly active-NCO-terminated isocyanate prepolymer A is as follows: 400 g of poly(1,6-hexanediol adipate) with a number average molecular weight of 2000 and 71 g of dihydroxy long-chain alkyl silicone oil IOTA-8865H are heated to 105° C. and dehydrated under vacuum for 2 h to obtain a mixed polyol. The obtained mixed polyol is mixed with 0.5 g of bismuth carboxylate, 20 g of DMF, 0.8 g of antioxidant 1010, and 3 8.3 g of m-xylylene diisocyanate was mixed evenly, the temperature was raised to 65°C and reacted for 2 hours, and the viscosity of the system was tested every 10 minutes. When the viscosity of the system was measured to be between 6000-8000 mPa·s / 25°C, 125.2 g of diphenylmethane-4,4'-diisocyanate MDI was added, and the mixture was reacted at 80°C for 1.0 hour under nitrogen protection to obtain isocyanate prepolymer A with an -NCO content of 6.62 wt%.

[0056] The low-activity-NCO-terminated isocyanate prepolymer B is prepared from 396 g of low-crystalline linear polyester polyol PLOS-ZY1200 with a number average molecular weight of 2200, 71 g of double-terminal alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H, 0.8 g of bismuth carboxylate, 16 g of DMF, 0.8 g of antioxidant 1010, 34.8 g of m-xylylene diisocyanate, and 151.2 g of capping agent-isophorone diisocyanate.

[0057] The preparation method of low-activity -NCO-terminated isocyanate prepolymer B is as follows: 396g of low-crystalline linear polyester polyol PLOS-ZY1200 with a number average molecular weight of 2200 and 71g of double-terminal alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H are heated to 105°C and dehydrated under vacuum conditions for 2h to obtain a mixed polyol. The obtained mixed polyol is evenly mixed with 0.8g of bismuth carboxylate, 16g of DMF, 0.8g of antioxidant 1010, and 34.8g of m-xylylene diisocyanate, and then heated to 70°C for reaction for 3h. After that, the viscosity of the system is tested every 10min. When the measured system viscosity is between 6000-8000mPa·s / 25°C, 151.2g of the blocking agent - isophorone diisocyanate is added, and the reaction is carried out at 90°C for 100min under nitrogen protection to obtain an isocyanate prepolymer B with an -NCO content of 8.75wt%.

[0058] The primary amine-terminated isocyanate prepolymer A is prepared from 200 g of poly(1,6-hexanediol adipate) with a number average molecular weight of 2000, 50 g of poly(tetramethylene ether glycol) PTMEG with a number average molecular weight of 1000 (BASF PolyTHF), 100 g of polycarbonate diol PCDL 1012 with a number average molecular weight of 2000 (Guangzhou Haoyi New Materials Technology Co., Ltd.), 0.88 g of bismuth carboxylate, 18 g of DMF, 0.8 g of antioxidant 1010, 55.1 g of diphenylmethane-4,4'-diisocyanate, and 8.15 g of capping agent-1,6-hexanediamine.

[0059] The preparation method of primary amine-terminated isocyanate prepolymer A is as follows: 200 g of poly(1,6-hexanediol adipate) with a number average molecular weight of 2000, 50 g of poly(tetramethylene ether glycol) PTMEG with a number average molecular weight of 1000, and 100 g of poly(carbonate diol) PCDL with a number average molecular weight of 2000 are mixed. 1012 was heated to 105°C and dehydrated under vacuum conditions for 2h to obtain a mixed polyol. The obtained mixed polyol was evenly mixed with 0.88g bismuth carboxylate, 18g DMF, 0.8g antioxidant 1010, and 55.1g diphenylmethane-4,4'-diisocyanate, and then heated to 65°C for reaction for 1h. The viscosity of the system was tested every 10min. When the viscosity of the system was measured to be between 6000-8000mPa·s / 25°C, 8.15g of blocking agent -1,6-hexanediamine was added, and the mixture was reacted at 80°C for 1.0h under nitrogen protection to obtain a primary amine-terminated isocyanate prepolymer A with a primary amine group of 0.77wt%.

[0060] The primary hydroxyl-terminated isocyanate prepolymer B is prepared from 200 g of low-crystalline dimer acid polyester polyol PLOS-ZY2250 with a number average molecular weight of 2500, 50 g of polytetramethylene ether glycol PTMEG with a number average molecular weight of 1000, 30 g of HX-209 hydroxyl-terminated methyl vinyl silicone oil (Wuhan Huaxiang Kejie Biotechnology Co., Ltd., hydroxyl content: 6±0.5 mol%, vinyl content: 6±0.5 mol%), 0.94 g of bismuth carboxylate, 20 g of DMF, 0.8 g of antioxidant 1010, 44.45 g of isophorone diisocyanate, and 13.7 g of capping agent-bisphenol A dihydroxyethyl ether.

[0061] The preparation method of primary hydroxyl-terminated isocyanate prepolymer B is as follows: 200g of low-crystalline dimer acid polyester polyol PLOS-ZY2250 with a number average molecular weight of 2500, 50g of polytetramethylene ether glycol PTMEG with a number average molecular weight of 1000, and 30g of HX-209 hydroxyl-terminated methyl vinyl silicone oil are heated to 105°C and dehydrated under vacuum conditions for 2h to obtain a mixed polyol, and the obtained mixed polyol is mixed with 0.94g of bismuth carboxylate, 20g of DMF, 0.8g antioxidant 1010 and 44.45g isophorone diisocyanate were mixed evenly, heated to 70°C and reacted for 1.5h, and the viscosity of the system was tested every 10min. When the viscosity of the system was measured to be between 6000-8000mPa·s / 25°C, 13.7g of end-capping agent, bisphenol A dihydroxyethyl ether, was added, and the mixture was reacted at 85°C for 1.5h under nitrogen protection to obtain a primary hydroxyl-terminated isocyanate prepolymer B with a primary hydroxyl content of 0.76wt%.

[0062] A method for preparing a hot melt adhesive with high bonding strength is as follows: 12 parts of a high-activity NCO-terminated isocyanate prepolymer A, 18 parts of a low-activity NCO-terminated isocyanate prepolymer B, 6 parts of a primary amine-terminated isocyanate prepolymer A, and 8 parts of a primary hydroxyl-terminated isocyanate prepolymer B are mixed under nitrogen protection, and then 8 parts of a thermoplastic EVA resin and 4 parts of an organic polysilazane MY are added. 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 5 parts of fumed silica N20, 2 parts of defoaming agent - BASF Efka2720, heat to 100°C, stir for 30-45 minutes under vacuum -0.09MPa, after vacuum degassing, cool to room temperature and package in black sealed bag to produce hot melt adhesive with high bonding strength.

[0063] The difference between Example 2 and Example 1 is that the hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 18 parts of high-activity-NCO-terminated isocyanate prepolymer A, 12 parts of low-activity-NCO-terminated isocyanate prepolymer B, 8 parts of primary amine-terminated isocyanate prepolymer A, 6 parts of primary hydroxyl-terminated isocyanate prepolymer B, 8 parts of thermoplastic EVA resin, 3.2 parts of organic polysilazane MY 9150, 1.2 parts of trimethylolpropane triacrylate, 0.8 parts of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 4 parts of fumed silica N20, and 1.8 parts of defoaming agent-BASF Efka 2720.

[0064] The difference between Example 3 and Example 1 is that the hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 15 parts of high-activity-NCO-terminated isocyanate prepolymer A, 15 parts of low-activity-NCO-terminated isocyanate prepolymer B, 8 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 8 parts of thermoplastic EVA resin, 3 parts of organic polysilazane MY 9150, 1.2 parts of trimethylolpropane triacrylate, 0.8 parts of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 6 parts of fumed silica N20, and 2.4 parts of defoaming agent-BASF Efka 2720.

[0065] The difference between Example 4 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 5 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of defoaming agent-BASF Efka 2720.

[0066] The difference between Example 5 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 12 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of defoaming agent-BASF Efka 2720.

[0067] The difference between Example 6 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 20 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of defoaming agent-BASF Efka 2720.

[0068] The difference between Example 7 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 18 parts of high-activity-NCO-terminated isocyanate prepolymer A, 12 parts of low-activity-NCO-terminated isocyanate prepolymer B, 8 parts of primary amine-terminated isocyanate prepolymer A, 6 parts of primary hydroxyl-terminated isocyanate prepolymer B, 8 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1.2 parts of tris (2-hydroxyethyl) isocyanurate triacrylate, 0.8 parts of γ-glycidyloxypropyl trimethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-resistant agent UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 5 parts of fumed silica N20, 2 parts of defoaming agent-BASF Efka 2723.

[0069] The difference between Example 8 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 18 parts of high-activity NCO-terminated isocyanate prepolymer A, 12 parts of low-activity NCO-terminated isocyanate prepolymer B, 8 parts of primary amine-terminated isocyanate prepolymer A, 6 parts of primary hydroxyl-terminated isocyanate prepolymer B, 8 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of pentaerythritol triacrylate, 1 part of γ-methacryloxypropyltrimethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of Evonik TEGO Airex 963.

[0070] The difference between Example 9 and Example 1 is that the primary hydroxyl-terminated isocyanate prepolymer B is prepared from 200g of low-crystalline dimer acid polyester polyol PLOS-ZY2250 with a number average molecular weight of 2500, 50g of polytetramethylene ether glycol PTMEG with a number average molecular weight of 1000, 100g of polycarbonate diol PCDL 1012 with a number average molecular weight of 2000, 0.94g of bismuth carboxylate, 20g of DMF, 0.8g of antioxidant 1010, 44.45g of isophorone diisocyanate, and 13.7g of capping agent-bisphenol A dihydroxyethyl ether.

[0071] The preparation method of primary hydroxyl terminated isocyanate prepolymer B is as follows: 200 g of low crystalline dimer acid polyester polyol PLOS-ZY2250 with a number average molecular weight of 2500, 50 g of polytetramethylene ether glycol PTMEG with a number average molecular weight of 1000, and 100 g of polycarbonate diol PCDL with a number average molecular weight of 2000 are mixed. 1012 was heated to 105° C. and dehydrated under vacuum conditions for 2 h to obtain a mixed polyol. The obtained mixed polyol was evenly mixed with 0.94 g of bismuth carboxylate, 20 g of DMF, 0.8 g of antioxidant 1010, and 44.45 g of isophorone diisocyanate, and then heated to 70° C. for reaction for 1.5 h, and the viscosity of the system was tested every 10 min. When the viscosity of the system was measured to be between 6000 and 8000 mPa·s / 25° C., 13.7 g of a blocking agent, bisphenol A dihydroxyethyl ether, was added, and the mixture was reacted at 85° C. for 1.5 h under nitrogen protection to obtain a primary hydroxyl-terminated isocyanate prepolymer B with a primary hydroxyl content of 0.63 wt%.

[0072] The difference between Example 10 and Example 1 is that the hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 20 parts of high-activity-NCO-terminated isocyanate prepolymer A, 10 parts of low-activity-NCO-terminated isocyanate prepolymer B, 5 parts of primary amine-terminated isocyanate prepolymer A, 10 parts of primary hydroxyl-terminated isocyanate prepolymer B, 8 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1.2 parts of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 4 parts of fumed silica N20, and 1.8 parts of BASF Efka 2720.

[0073] Highly active-NCO-terminated isocyanate prepolymer A is made of 400g of polyadipate-1,6-hexanediol ester diol with a number average molecular weight of 2000, 71g of double-end alcohol hydroxyl long-chain alkyl silicone oil IOTA-8865H, 0.5g of bismuth carboxylate, 20g of DMF, 0.8g of antioxidant 1010, 38.3g of m-xylylene diisocyanate, and 220.2g of end-capping agent-diphenylmethane-4,4'-diisocyanate. The NCO content in the highly active-NCO-terminated isocyanate prepolymer A is 10.1wt%.

[0074] Comparative Example

[0075] The difference between Comparative Example 1 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 44 parts of highly active -NCO-terminated isocyanate prepolymer A, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyltriethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of BASF Efka 2720.

[0076] The difference between Comparative Example 2 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 30 parts of high-activity -NCO-terminated isocyanate prepolymer A, 14 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyltriethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of BASF Efka 2720.

[0077] The difference between Comparative Example 3 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 30 parts of high-activity -NCO-terminated isocyanate prepolymer A, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 8 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of BASF Efka 2720.

[0078] The difference between Comparative Example 4 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 44 parts of -NCO-terminated isocyanate prepolymer, 4 parts of organic polysilazane MY 9150, 1 part of 3-isocyanatepropyltriethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of BASF Efka 2720.

[0079] The -NCO terminated isocyanate prepolymer is made of 300g of poly(1,6-hexanediol adipate) with a number average molecular weight of 2000, 90g of poly(tetramethylene ether glycol) PTMEG with a number average molecular weight of 1000, 0.58g of bismuth carboxylate, 25g of DMF, 1g of antioxidant 1010, 38.3g of m-xylylene diisocyanate, and 220.2g of diphenylmethane-4,4'-diisocyanate MDI.

[0080] The preparation method of highly active -NCO-terminated isocyanate prepolymer A is as follows: 300g of poly(1,6-hexanediol adipate) with a number average molecular weight of 2000 and 90g of poly(PTMEG) with a number average molecular weight of 1000 are heated to 105°C and dehydrated under vacuum conditions for 2h to obtain a mixed polyol; the obtained mixed polyol is evenly mixed with 0.58g of bismuth carboxylate, 250g of DMF, 1g of antioxidant 1010, and 38.3g of m-xylylene diisocyanate, and then heated to 65°C and reacted for 1.5h, and the viscosity of the system is tested every 10min. When the measured system viscosity is between 6000-8000mPa·s / 25°C, 220.2g of diphenylmethane-4,4'-diisocyanate is added, and the mixture is reacted at 80°C for 1.0h under nitrogen protection to obtain an isocyanate prepolymer with an -NCO content of 11.4wt%.

[0081] The difference between Comparative Example 5 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyltriethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of BASF Efka 2720.

[0082] The difference between Comparative Example 6 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 2 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of BASF Efka 2720.

[0083] The difference between Comparative Example 7 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 22 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of BASF Efka 2720.

[0084] The difference between Comparative Example 8 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 5 parts of thermoplastic EVA resin, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyltriethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of catalyst dimorpholine diethyl ether, 5 parts of fumed silica N20, and 2 parts of BASF Efka 2720.

[0085] The difference between Comparative Example 9 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 5 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyltriethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV inhibitor UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether N20, and 2 parts of BASF Efka 2720.

[0086] The difference between Comparative Example 10 and Example 1 is that a hot melt adhesive with high bonding strength is made of the following raw materials in parts by mass: 12 parts of high-activity-NCO-terminated isocyanate prepolymer A, 18 parts of low-activity-NCO-terminated isocyanate prepolymer B, 6 parts of primary amine-terminated isocyanate prepolymer A, 8 parts of primary hydroxyl-terminated isocyanate prepolymer B, 8 parts of thermoplastic EVA resin, 4 parts of organic polysilazane MY 9150, 1 part of trimethylolpropane triacrylate, 1 part of 3-isocyanatepropyl triethoxysilane, 0.6 parts of antioxidant 1010, 0.2 parts of antioxidant 168, 0.5 parts of UV-622, 0.05 parts of bismuth carboxylate, 0.25 parts of bismorpholine diethyl ether, 10 parts of fumed silica N20, and 2 parts of defoaming agent-BASF Efka 2720.

[0087] Performance testing

[0088] 1. The appearance inspection method is as follows: observe the appearance changes of the hot melt adhesive after storing it at room temperature and humidity 60% RH for 14 days.

[0089] 2. Storage stability test: The reactive polyurethane hot melt adhesives prepared in Examples 1-10 and Comparative Examples 1-9 were sealed and placed in stainless steel packaging cans (with a polytetrafluoroethylene non-stick coating on the inner wall), and the stainless steel packaging cans were placed in an electric blast drying oven and stored at 50°C for 14 days. After 14 days, the hot melt adhesives were tested for crusting and stratification.

[0090] 3. Adhesive properties of PA substrate. Test method: Melt glue on PA substrate at 150℃, shear the sample and control the thickness of the glue layer to 0.25mm, let it stand and cure for 3 days at 25℃ and 60%RH, and test the shear strength of the sample. The shear strength test is in accordance with GB / T 7124-2008 Determination of tensile shear strength of adhesives.

[0091] 4. Adhesive properties of silicone substrate. Test method: Melt the glue on the silicone substrate at 150°C, cut the sample and control the thickness of the glue layer to 0.25mm, let it stand and cure for 3 days at a temperature of 25°C and a humidity of 60% RH, and test the shear strength of the sample.

[0092] 5. Weather resistance test: After the reactive polyurethane hot melt adhesive is cured at 85°C / 85% RH for 14 days, the obtained test sample is placed in an oven at 120°C for 24 hours, and then the tensile shear strength of the test sample is tested at 120°C.

[0093] 6. 180° peel strength test According to GB / T 2790-1995 adhesive 180° peel strength test method, the bonding object of the reactive polyurethane hot melt adhesive is GS0102 silicone plate (tearing force: 6Mpa; elongation: 300%; hardness: 55°±5°).

[0094] Data analysis

[0095] Table 1: Test parameter table of reactive polyurethane hot melt adhesive in Examples 1-10 and Comparative Examples 1-10

[0096]

[0097]

[0098] From the analysis of Examples 1-3 and Comparative Examples 1-4 in combination with Table 1, it can be seen that the high bonding strength hot melt adhesive prepared by the reactive polyurethane hot melt adhesive formula in the present application has good bonding strength to the PA substrate and also has good bonding strength to the silicone substrate. When applied to the field of nylon composite cloth fabric bonding, it has relatively good bonding strength and bonding stability to the nylon PA substrate. The silicone surface layer is bonded and fixed to the nylon composite cloth by the hot melt adhesive with high bonding strength, thereby expanding the use of the above-mentioned hot melt adhesive.

[0099] From the analysis of Example 1 and Examples 4-6 and Comparative Examples 5-7 in combination with Table 1, it can be seen that the addition of thermoplastic EVA resin can improve the overall bonding strength, but it will also affect the weather resistance of the final adhesive layer. Therefore, the addition amount of thermoplastic EVA resin in the reactive polyurethane hot melt adhesive formula is preferably controlled at 5-20 parts, and the preferred addition range is controlled between 8-10 parts.

[0100] From the analysis of Example 1 and Comparative Example 8 in combination with Table 1, it can be seen that the organopolysilazane MY 9150 can improve the bonding stability and weather resistance of the reactive polyurethane hot melt adhesive, and avoid the poor permeability and low pinholes in the adhesive layer caused by the reaction speed.

[0101] From the analysis of Example 1 and Comparative Examples 9-10 combined with Table 1, it can be seen that the fumed silica N20 used in the present application can improve the bonding performance between the prepared reactive polyurethane hot melt adhesive and the silicone substrate and at the same time provide overall weather resistance and service life. However, too much fumed silica N20 will cause a significant decrease in the overall bonding strength, and the added amount needs to be controlled between 4-6 parts.

[0102] 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 adhesive with high bonding strength, characterized in that: It is mainly made of the following raw materials in parts by mass: 10-20 parts of high-activity-NCO-terminated isocyanate prepolymer A, 10-20 parts of low-activity-NCO-terminated isocyanate prepolymer B, 5-10 parts of primary amine-terminated isocyanate prepolymer A, 5-10 parts of primary hydroxyl-terminated isocyanate prepolymer B, 5-20 parts of thermoplastic EVA resin, 1-5 parts of organic polysilazane MY 9150, 0.5-2 parts of a cross-linking agent, 0.5-2 parts of a coupling agent, 0.5-2 parts of an antioxidant, 0.5-2 parts of an anti-ultraviolet agent, 0.05-0.5 parts of a catalyst, 4-8 parts of fumed silica, and 1-3 parts of a defoaming agent; the total molar amount of -NCO in the high-activity -NCO-terminated isocyanate prepolymer A and the low-activity -NCO-terminated isocyanate prepolymer B is 0.5-2 times the total molar amount of the primary amine in the primary amine-terminated isocyanate prepolymer A and the primary hydroxyl in the primary hydroxyl-terminated isocyanate prepolymer B; The highly active NCO-terminated isocyanate prepolymer A comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, m-xylylene diisocyanate, and a capping agent - diphenylmethane-4,4'-diisocyanate; the polyol is composed of a highly crystalline polyol and a dihydroxy-terminated silicone oil in a mass ratio of (8-9):(1-2); the dihydroxy-terminated silicone oil is at least one of hydroxy-terminated methyl vinyl silicone oil, double-terminated hydroxypropyl silicone oil, and double-terminated alcohol hydroxy long-chain alkyl silicone oil; the highly crystalline polyol is at least one of poly(1,6-hexanediol adipate)diol and poly(1,6-hexanediol sebacate)diol with a molecular weight of 1000 to 4000 g / mol; the mass of the capping agent in the highly active NCO-terminated isocyanate prepolymer A accounts for 5-20% of the highly active NCO-terminated isocyanate prepolymer A; The low-reactive-NCO-terminated isocyanate prepolymer B comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, m-xylylene diisocyanate, and a capping agent-isophorone diisocyanate; the polyol is composed of a low-crystalline polyol and a dihydroxy-terminated silicone oil in a mass ratio of (8-9):(1-2); the dihydroxy-terminated silicone oil is at least one of a hydroxy-terminated methyl vinyl silicone oil, a double-terminated hydroxypropyl silicone oil, and a double-terminated alcohol hydroxyl long-chain alkyl silicone oil; the low-crystalline polyol is a low-crystalline linear polyester polyol PLOS-ZY1200 with a molecular weight of 2200 or a low-crystalline dimer acid polyester polyol PLOS-ZY2250 with a molecular weight of 2500; the mass of the capping agent in the low-reactive-NCO-terminated isocyanate prepolymer B accounts for 5-20% of the total amount of the low-reactive-NCO-terminated isocyanate prepolymer B; The primary amine-terminated isocyanate prepolymer A comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, diphenylmethane-4,4'-diisocyanate, and end-capping agent-1,6-hexanediamine; the polyol is a highly crystalline polyol, a polyether diol, and a polycarbonate diol in a mass ratio of (6-8):(1-2):(1-2); the highly crystalline polyol is at least one of poly(1,6-hexanediol adipate) diol and poly(1,6-hexanediol sebacate) diol with a molecular weight of 1000 to 4000 g / mol; the mass of the primary amine in the primary amine-terminated isocyanate prepolymer A accounts for 0.5-2% of the total amount of the primary amine-terminated isocyanate prepolymer A; The primary hydroxyl-terminated isocyanate prepolymer B comprises polyol, bismuth carboxylate, DMF, antioxidant 1010, isophorone diisocyanate, and a capping agent - bisphenol A dihydroxyethyl ether; the polyol is a low-crystalline polyol combined with at least one of hydroxyl-terminated methyl vinyl silicone oil, polyether diol, and polycarbonate diol; the low-crystalline polyol is a low-crystalline linear polyester polyol PLOS-ZY1200 with a molecular weight of 2200 or a low-crystalline dimer acid polyester polyol PLOS-ZY2250 with a molecular weight of 2500; the mass of primary hydroxyl groups in the primary hydroxyl-terminated isocyanate prepolymer B accounts for 0.5-2% of the total amount of the primary hydroxyl-terminated isocyanate prepolymer B.

2. A hot melt adhesive with high bonding strength according to claim 1, characterized in that: The method for preparing the hot melt adhesive with high bonding strength comprises the following steps: Step 1: Preparation of highly active -NCO-terminated isocyanate prepolymer A: The polyol is heated to 100-110°C and dehydrated under vacuum conditions for 1-4 hours. The obtained polyol is mixed evenly with bismuth carboxylate, DMF, antioxidant 1010, and m-xylylene diisocyanate, and then heated to 65-70°C to react until the system viscosity is 3000-12000mPa·s / 25°C, and then a blocking agent - diphenylmethane-4,4'-diisocyanate is added, and the reaction is carried out at 80-85°C for 0.5-2h to obtain an isocyanate prepolymer A with an -NCO content of 5-20wt%; Preparation of low-activity -NCO-terminated isocyanate prepolymer B: heating the polyol to 100-110°C and dehydrating under vacuum for 1-4h, mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010, and m-xylylene diisocyanate, heating to 65-70°C and reacting until the system viscosity is 3000-12000mPa·s / 25°C, adding the blocking agent - isophorone diisocyanate, reacting at 90-95°C for 0.5-2h, and obtaining an isocyanate prepolymer B with an -NCO content of 5-20wt%; Preparation of primary amine-terminated isocyanate prepolymer A: heating a polyol to 100-110° C. and dehydrating it under vacuum for 1-4 hours, uniformly mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010, and diphenylmethane-4,4'-diisocyanate, heating the mixture to 65-70° C. and reacting the mixture until the system viscosity reaches 3000-12000 mPa·s / 25° C., adding a capping agent - 1,6-hexanediamine, and reacting the mixture at 75-85° C. for 0.5-2 hours, thereby obtaining a primary amine-terminated isocyanate prepolymer A having a primary amine group content of 0.5-2 wt%; Preparation of primary hydroxyl terminated isocyanate prepolymer B: heating a polyol to 100-110° C. and dehydrating under vacuum for 1-4 h, uniformly mixing the obtained polyol with bismuth carboxylate, DMF, antioxidant 1010 and isophorone diisocyanate, heating the mixture to 75-80° C. and reacting until the system viscosity reaches 3000-12000 mPa·s / 25° C., adding a capping agent, bisphenol A dihydroxyethyl ether, and reacting the mixture at 90-95° C. for 0.5-2 h, thereby obtaining a primary hydroxyl terminated isocyanate prepolymer B having a primary hydroxyl content of 0.5-2 wt%; Step 2: Mix the high-activity NCO-terminated isocyanate prepolymer A, the low-activity NCO-terminated isocyanate prepolymer B, the primary amine-terminated isocyanate prepolymer A, and the primary hydroxyl-terminated isocyanate prepolymer B in step 1 under nitrogen protection, add 5-20 parts of thermoplastic EVA resin, 1-5 parts of organic polysilazane MY 9150, a crosslinking agent, a coupling agent, an antioxidant, an anti-ultraviolet agent, a catalyst, fumed silica, and a defoaming agent, heat to 98-100° C., stir for 30-45 minutes under vacuum at -0.09 to -0.08 MPa, and after vacuum degassing, cool to room temperature and package in a black sealed bag.

3. A hot melt adhesive with high bonding strength according to claim 2, characterized in that: The crosslinking agent is at least one of trimethylolpropane triacrylate, pentaerythritol triacrylate, and tris(2-hydroxyethyl)isocyanuric acid triacrylate; the coupling agent is at least one of γ-glycidyloxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and 3-isocyanatepropyltriethoxysilane.

4. A hot melt adhesive with high bonding strength according to claim 3, characterized in that: The antioxidant is composed of at least one of antioxidant 1010, antioxidant 1098, and antioxidant BHT and antioxidant 168; the anti-ultraviolet agent is at least one of UV-531, UV-326, UV-320, and UV-622.

5. The hot melt adhesive with high bonding strength according to claim 3, characterized in that: The catalyst is at least one of stannous octoate, bismuth carboxylate and diethyl bismorpholine; the defoamer is at least one of BASF Efka 2720, Efka2723 and Evonik TEGO Airex 963.

6. An application of a hot melt adhesive with high bonding strength as described in any one of claims 1 to 5 in silicone and nylon composite cloth, wherein the hot melt adhesive with high bonding strength is applied in the field of bonding nylon composite cloth fabrics, and the silicone surface layer and the nylon composite cloth are bonded and fixed by the hot melt adhesive with high bonding strength.

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