A moisture-curing polyurethane adhesive and its preparation method and application

Abstract

The present invention discloses a moisture-curing polyurethane adhesive and a preparation method and application thereof, belonging to the technical field of functional polymer materials. The present invention utilizes a combination of polypropylene polyol and polycaprolactone polyol to polymerize with isocyanate to prepare a polyurethane prepolymer, and then obtains a moisture-curing polyurethane adhesive by reacting with components such as a curing accelerator, a filler, a dehydrating agent, a pigment and a defoamer. The polyurethane adhesive of the present invention can quickly initiate a curing reaction using only a trace amount of water vapor in the air and exhibits excellent mechanical strength in a short time. At the same time, the introduction of polycaprolactone polyol imparts good biocompatibility and degradability, laying a good foundation for subsequent recycling; in addition, the polyurethane adhesive of the present invention has a simple production process and a long product storage time. It can meet the medical and other emergency repair and reinforcement fields by optimizing and regulating the types and ratios of polyether polyols, isocyanate monomers, curing accelerators, pigments, fillers and additives, and has broad application prospects.

Description

Technical Field

[0001] The invention belongs to the technical field of functional polymer materials, and specifically relates to a moisture-curing polyurethane adhesive and a preparation method and application thereof. Background Art

[0002] Polyurethane adhesives, referred to as PU adhesives, contain multiple polar groups such as carbamate groups, ester groups and ether groups in their molecular structures, which can form hydrogen bonds with hydrogen-containing polar groups on the bonded materials, making polyurethane adhesives have very strong bonding properties and are widely used in the bonding of metals, wood, fibers, plastics, etc. Among them, single-component moisture-curing polyurethane adhesives are a type of adhesive that uses the free active isocyanate groups in the polymer to react with water vapor in the atmosphere or active hydrogen atoms in the bonding substrate to achieve the purpose of bonding. The reaction medium is mainly water, and no heating or other energy is required, so there is no problem of volatile organic compounds, and after curing, it has better wear resistance, thermal stability, hardness and chemical stability.

[0003] At present, single-component moisture-curing polyurethane adhesives have been widely used in various fields of industrial and agricultural production and life. Taking the application in the medical field as an example, for patients with fractures, plaster bandages are often used for reinforcement to help patients' bones heal. Although the price of plaster is low and the source is sufficient, the disadvantages of plaster are high density, airtightness, low X-ray transmittance and easy breakage, which can easily cause secondary infection and bring trouble to treatment. The current mainstream technology is to use thermosetting resins that can meet the performance requirements to impregnate softened glass fiber knitted fabrics to prepare medical glass fiber bandages. Commonly used thermosetting resins include epoxy resins, unsaturated resins and polyurethane adhesives. Epoxy resin adhesives must be added with curing agents or cross-linking agents during curing, and heating is required to promote the cross-linking reaction, and the curing speed is slow, which does not meet the requirements of glass fiber bandage coatings; unsaturated resin adhesives can be cured at room temperature without the need for additional curing agents or cross-linking agents, but the curing time is long and the bonding strength is low, which does not meet the requirements of glass fiber bandage coatings. Therefore, a polyurethane adhesive is selected to impregnate the glass fiber, and then a polyurethane adhesive for coating the glass fiber that meets the technical requirements is developed by adjusting the component content, changing the process formula, temperature and humidity and other conditions. However, there are still many defects in the current wet-curing polyurethane adhesive, such as the slow curing rate of the wet-curing method, the long time for the film to be completely cured, and the low mechanical strength after curing and hardening, which limit the further promotion and application of glass fiber bandages coated with wet-curing polyurethane adhesive. CN201910211039.0 discloses a polyurethane resin composite for coating medical bandages, which has a relatively complex production process, and its strength after curing is measured by immersion in water, which is quite different from the actual application conditions, and the mechanical properties after curing and hardening need to be further improved. In addition, the degradability of the polyurethane resin composite for bandage coating is not involved. Summary of the invention

[0004] In order to solve the deficiencies of the prior art, the primary purpose of the present invention is to provide a novel moisture-curing polyurethane adhesive. The present invention also provides a method for preparing the novel moisture-curing polyurethane adhesive.

[0005] At the same time, another object of the present invention is to provide an application of a new type of moisture-curing polyurethane adhesive, specifically coating the moisture-curing polyurethane adhesive on glass fiber, and applying it to the medical field of multi-position fixation in orthopedics, orthotics, prosthetic assistive devices and support tools in plastic surgery, and local protective stents in burns, and other emergency repair and reinforcement fields.

[0006] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0007] A moisture-curing polyurethane adhesive is prepared from the following raw materials in total parts: 85-90 parts of a polyurethane prepolymer component, 1-3 parts of a curing accelerator, 1-5 parts of a filler, 1-3 parts of a dehydrating agent, 2-4 parts of a pigment, and 1-3 parts of a defoaming agent.

[0008] Furthermore, the polyurethane prepolymer component is obtained by polymerization reaction between active hydroxyl groups OH of polyether polyol and active isocyanate functional groups NCO in isocyanate monomers. The specific preparation steps are: adding polyether polyol to a reaction kettle, heating to 110° C. with nitrogen, vacuum dehydrating for 1 hour, adding isocyanate monomer, stirring the reaction for 2-3 hours, terminating the reaction, cooling to room temperature, and discharging to obtain the polyurethane prepolymer component.

[0009] Furthermore, the polyether polyol is polycaprolactone polyol PCL and polypropylene polyol.

[0010] The polypropylene polyol is one of polypropylene glycol PPG600, polypropylene glycol PPG800, polypropylene glycol N303 and polypropylene glycol N306.

[0011] The polycaprolactone polyol PCL has a general structure (I):

[0012]

[0013] In the polycaprolactone polyol PCL described in formula I, R is a molecular skeleton segment of a polyol (ethylene glycol, glycerol, trimethylolpropane, pentaerythritol);

[0014] The molecular weight (Mw) of the polycaprolactone polyol PCL of formula I is 400-800, the repeating unit (x) of the polycaprolactone PCL segment is 1-5, and the hydroxyl functionality (y) is 2-4.

[0015] The polycaprolactone polyol PCL is one of ethylene glycol-based polycaprolactone diol, glycerol-based polycaprolactone triol, trimethylolpropane-based polycaprolactone triol, and pentaerythritol-based polycaprolactone tetraol.

[0016] Furthermore, the mass ratio of polypropylene polyol to polycaprolactone polyol in the polyether polyol is (3-4):(1-2).

[0017] Furthermore, the isocyanate monomer is one or more of diphenylmethane diisocyanate MDI, polymethylene polyphenyl isocyanate PAPI, toluene diisocyanate TDI, isophorone diisocyanate IPDI, and dicyclohexylmethane diisocyanate HMDI.

[0018] Furthermore, the mass ratio of the polyether polyol to the isocyanate monomer is (4-5):(5-6).

[0019] Furthermore, the curing accelerator is one or more of bismorpholinyl diethyl ether and dibutyltin dilaurate; the filler is one or more of nano-scale white carbon black, calcium oxide, and zinc oxide; the pigment is one or more of oily phthalocyanine blue, phthalocyanine green, carbon black, and iron red paste; and the dehydrating agent is one or more of methanesulfonic acid, maleic anhydride, itaconic anhydride, and molecular sieves.

[0020] Furthermore, the defoaming agent refers to a silicone defoaming agent.

[0021] A method for preparing a moisture-curing polyurethane adhesive comprises the following preparation steps: adding a polyurethane prepolymer component into a reaction kettle, passing nitrogen and heating to 50-60° C., then respectively adding a filler, a pigment, a dehydrating agent and a defoaming agent, stirring evenly for 0.5 h, adding a curing accelerator, and continuing the reaction for 0.5 h to obtain the moisture-curing polyurethane adhesive, which can be sealed for storage.

[0022] The invention discloses an application of a moisture-curing polyurethane adhesive, specifically coating the moisture-curing polyurethane adhesive on glass fiber, and applying the moisture-curing polyurethane adhesive to the medical field of orthopedic multi-position fixation, plastic surgery orthopedics, prosthetic auxiliary appliances and support tools, local protective brackets in burns, and other emergency repair and reinforcement fields.

[0023] Beneficial Effects

[0024] (1) The novel moisture-curing polyurethane adhesive of the present invention adopts a combination of polyether polyol and isocyanate monomer to react, which gives it excellent bonding properties. At the same time, it can also use trace amounts of water vapor in the air to quickly initiate a curing reaction and exhibit excellent mechanical strength within a short period of 3 to 5 minutes.

[0025] (2) The introduction of polycaprolactone polyol in the present invention endows the moisture-curing polyurethane adhesive with good biocompatibility and degradability, laying a good foundation for subsequent recycling;

[0026] (3) The novel moisture-curing polyurethane adhesive of the present invention has a simple production process and a long storage time. It can also meet the medical application needs by optimizing and regulating the types and ratios of polyether polyols, isocyanate monomers, curing accelerators, pigments, fillers and additives. At the same time, it can also take into account other related emergency repair and reinforcement fields, and thus has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The structural formula of the polycaprolactone polyol PCL of the present invention is: (a) is ethylene glycol-based polycaprolactone diol, (b) is glycerol-based polycaprolactone triol, (c) is trimethylolpropane-based polycaprolactone triol, and (d) is pentaerythritol-based polycaprolactone tetraol;

[0028] Figure 2 This is a synthetic route for preparing a polyurethane prepolymer from ethylene glycol-based polycaprolactone diol, polypropylene glycol PPG600 and diphenylmethane diisocyanate MDI.

[0029] Figure 3 A glass fiber bandage not coated with the moisture-curing polyurethane adhesive of the present invention;

[0030] Figure 4 A glass fiber bandage coated with the moisture-curing polyurethane adhesive of the present invention;

[0031] Figure 5 Contact angles of glass fibers before (a) and after (b) coating with the moisture-curing polyurethane adhesive of the present invention;

[0032] Figure 6 The figure is a diagram showing the mechanism of action of the moisture-curing polyurethane adhesive coating glass fibers according to the present invention. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further described below in conjunction with specific embodiments, but is not limited thereto.

[0034] Example 1

[0035] A method for preparing a moisture-curing polyurethane adhesive comprises the following steps:

[0036] (1) Preparation of polyurethane prepolymer component: 20 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 40 kg of polypropylene glycol (PPG600, Mw≈600) were added to a reactor, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0037] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0038] Example 2

[0039] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0040] (1) Preparation of polyurethane prepolymer component: 20 kg of glycerol-based polycaprolactone triol (Mw≈600) and 40 kg of polypropylene glycol (PPG600, Mw≈600) were added to a reactor, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0041] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0042] Example 3

[0043] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0044] (1) Preparation of polyurethane prepolymer component: 20 kg of trimethylolpropane-based polycaprolactone triol (Mw≈600) and 40 kg of polypropylene glycol (PPG600, Mw≈600) were added to a reactor, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0045] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0046] Example 4

[0047] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0048] (1) Preparation of polyurethane prepolymer component: 20 kg of pentaerythritol-based polycaprolactone tetraol (Mw≈800) and 40 kg of polypropylene glycol (PPG600, Mw≈600) were added to a reactor, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0049] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0050] Example 5

[0051] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0052] (1) Preparation of polyurethane prepolymer component: 20 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 40 kg of polypropylene triol (N303, Mw≈300) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0053] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0054] Example 6

[0055] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0056] (1) Preparation of polyurethane prepolymer component: 20 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 40 kg of polypropylene triol (N306, Mw≈600) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0057] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0058] Example 7

[0059] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0060] (1) Preparation of polyurethane prepolymer component: 20 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 40 kg of polypropylene glycol (PPG800, Mw≈800) were added to a reactor, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0061] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0062] Example 8

[0063] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0064] (1) Preparation of polyurethane prepolymer component: 25 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 35 kg of polypropylene triol (N303, Mw≈300) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0065] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0066] Example 9

[0067] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0068] (1) Preparation of polyurethane prepolymer component: 30 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 30 kg of polypropylene triol (N306, Mw≈600) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0069] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0070] Example 10

[0071] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0072] (1) Preparation of polyurethane prepolymer component: 25 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 35 kg of polypropylene triol (N303, Mw≈300) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 85 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0073] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0074] Embodiment 11

[0075] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0076] (1) Preparation of polyurethane prepolymer component: 25 kg of propylene glycol-based polycaprolactone triol (Mw≈800) and 35 kg of polypropylene glycol (N303, Mw≈300) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0077] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0078] Example 12

[0079] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0080] (1) Preparation of polyurethane prepolymer component: 20 kg of pentaerythritol-based polycaprolactone tetraol (Mw≈600) and 40 kg of polypropylene glycol (PPG600, Mw≈600) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 85 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0081] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0082] Embodiment 13

[0083] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0084] (1) Preparation of polyurethane prepolymer component: 20 kg of pentaerythritol-based polycaprolactone tetraol (Mw≈800) and 40 kg of polypropylene glycol (PPG800, Mw≈800) were added to a reactor, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 85 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0085] (2) Preparation of moisture-curing polyurethane adhesive: According to parts by weight, 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60° C., then 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0086] Embodiment 14

[0087] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0088] (1) Preparation of polyurethane prepolymer component: 25 kg of pentaerythritol-based polycaprolactone tetraol (Mw≈800) and 35 kg of polypropylene triol (N303, Mw≈300) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 85 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0089] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0090] Embodiment 15

[0091] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0092] (1) Preparation of polyurethane prepolymer component: 20 kg of ethylene glycol-based polycaprolactone diol (Mw≈600) and 40 kg of polypropylene triol (N303, Mw≈300) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0093] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0094] Example 16

[0095] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0096] (1) Preparation of polyurethane prepolymer component: 20 kg of ethylene glycol-based polycaprolactone diol (Mw≈800) and 40 kg of polypropylene triol (N306, Mw≈600) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0097] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0098] Embodiment 17

[0099] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0100] (1) Preparation of polyurethane prepolymer component: 30 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 30 kg of polypropylene triol (N306, Mw≈600) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0101] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2.5 kg of maleic anhydride and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 1.5 kg of dibutyltin dilaurate was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0102] Embodiment 18

[0103] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0104] (1) Preparation of polyurethane prepolymer component: 25 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) and 35 kg of polypropylene triol (N303, Mw≈300) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 85 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0105] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C, then 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and stirred evenly for 0.5 h. 3 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0106] Embodiment 19

[0107] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0108] (1) Preparation of polyurethane prepolymer component: 20 kg of ethylene glycol-based polycaprolactone diol (Mw≈800) and 40 kg of polypropylene triol (N306, Mw≈600) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0109] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C, then 2.0 kg of calcium oxide, 2.5 kg of carbon black, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and stirred evenly for 0.5 h. 2.0 kg of dibutyltin dilaurate was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0110] Embodiment 20

[0111] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0112] (1) Preparation of polyurethane prepolymer component: 25 kg of pentaerythritol-based polycaprolactone tetraol (Mw≈800) and 35 kg of polypropylene triol (N303, Mw≈300) were added to a reaction kettle, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 85 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0113] (2) Preparation of moisture-curing polyurethane adhesive: 85 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 5 kg of white carbon black, 3.0 kg of phthalocyanine blue, 2.5 kg of methanesulfonic acid and 2.5 kg of silicone defoamer were added respectively, and stirred evenly for 0.5 h. 2.0 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0114] Comparative Example 1

[0115] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0116] (1) Preparation of polyurethane prepolymer component: 60 kg of ethylene glycol-based polycaprolactone diol (Mw≈400) was added to a reaction kettle, the temperature was raised to 110°C under nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0117] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0118] Comparative Example 2

[0119] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0120] (1) Preparation of polyurethane prepolymer component: 60 kg of polypropylene glycol (Mw≈600) was added to a reaction kettle, the temperature was raised to 110°C under nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0121] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0122] Comparative Example 3

[0123] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0124] (1) Preparation of polyurethane prepolymer component: 20 kg of polypropylene glycol (Mw≈600) and 40 kg of polypropylene triol (N303, Mw≈300) were added to a reactor, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0125] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0126] Comparative Example 4

[0127] A method for preparing a moisture-curing polyurethane adhesive is as follows, comprising the following steps:

[0128] (1) Preparation of polyurethane prepolymer component: 20 kg of polypropylene glycol (Mw≈600) and 40 kg of polypropylene triol (N306, Mw≈600) were added to a reactor, the temperature was raised to 110°C with nitrogen, and vacuum dehydration was performed for 1 hour. 80 kg of diphenylmethane diisocyanate (MDI) was added, and the reaction was stirred for 3 hours before the reaction was terminated. The mixture was cooled to room temperature and discharged to obtain the polyurethane prepolymer component.

[0129] (2) Preparation of moisture-curing polyurethane adhesive: 90 kg of polyurethane prepolymer components were added to a reactor, nitrogen was introduced and the temperature was raised to 50-60°C. Then, 1.5 kg of white carbon black, 2.5 kg of phthalocyanine blue, 2 kg of methanesulfonic acid and 2 kg of silicone defoamer were added respectively, and the mixture was stirred evenly for 0.5 h. 2 kg of bismorpholinyl diethyl ether was added and the reaction was continued for 0.5 h to obtain a moisture-curing polyurethane adhesive, which was then sealed and stored.

[0130] Performance Testing

[0131] The performance test of the moisture-curing polyurethane adhesive involved in the present invention refers to the standard of "Medical Bandages and Rescue Bandages" (YY / T1467-2016). (1) Storage stability: observe the viscosity change of the new moisture-curing polyurethane adhesive after it is placed for 6 months. (2) Viscosity determination: use a rotational viscometer (NDJ-8) to measure the viscosity of the moisture-curing polyurethane adhesive. The measurement should be carried out quickly under room temperature and dry conditions. (3) Curing time test: apply an appropriate amount of moisture-curing polyurethane adhesive on the glass fiber, then scrape it completely with a scraper, and use a stopwatch to record the time (min) when the stickiness on the surface of the adhesive layer disappears. The judgment standard is that it is not sticky. (4) Contact angle test: using blank glass fiber as a control, the static contact angle (θ) of the moisture-curing polyurethane adhesive before and after coating on the glass fiber surface is determined by the hanging drop method, and then used to evaluate the wettability of the coating. (5) Mechanical strength test: With blank glass fiber as control, the glass fiber bandage with wet-cured polyurethane adhesive and fully cured was used as the sample, and the tensile strength and burst strength were measured using an electronic universal testing machine. The specific results are shown in Table 1:

[0132] Table 1 Performance of the novel moisture-curing polyurethane adhesive of the present invention

[0133]

[0134] The results show that compared with Comparative Examples 3 and 4, the embodiment of the present invention introduces a more flexible polycaprolactone polyol segment, so the viscosity of the prepared moisture-curing polyurethane adhesive is moderate, which is more conducive to subsequent industrial coating and coating. When used for glass fiber coating, the glass fiber bandage not coated with the moisture-curing polyurethane adhesive is very soft, but after coating the moisture-curing polyurethane adhesive prepared by the present invention, it will be quickly cured and formed, and only a trace amount of water vapor in the air can be used to initiate the curing reaction, and excellent mechanical strength is shown in a short time of 3 to 5 minutes. This is because the remaining isocyanate groups in the polyurethane adhesive are cured with the glass fiber bandage or water vapor in the air, and the moisture-curing polyurethane adhesive structure of the present invention contains both rigid benzene rings and carbamate bonds, and also contains polycaprolactone polyol segments with better toughness, so its unique soft and hard segment molecular structure gives the glass fiber excellent strength, hardness and toughness. The contact angle measurement further shows that the moisture-curing polyurethane adhesive coated on the glass fiber is cured and hardened, and is well combined with the glass fiber to form a quasi-interpenetrating polymer-glass fiber network structure. In addition, the polycaprolactone polyol with good biocompatibility and degradability introduced in the present invention also lays a good foundation for the subsequent recycling of the coated stripped fibers.

[0135] It should be noted that the above embodiments are only partial embodiments of the preferred methods of implementing the present invention, rather than all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

Claims

1. A moisture-curing polyurethane adhesive, characterized in that: The method is prepared from the following raw materials in total: 85-90 parts of polyurethane prepolymer component, 1-3 parts of curing accelerator, 1-5 parts of filler, 1-3 parts of dehydrating agent, 2-4 parts of pigment, and 1-3 parts of defoaming agent; The polyurethane prepolymer component is obtained by polymerization reaction between active hydroxyl groups of polyether polyol and active isocyanate functional groups in isocyanate monomers. The specific preparation steps are: adding polyether polyol to a reaction kettle, heating to 110° C. with nitrogen, vacuum dehydrating for 1 hour, adding isocyanate monomer, stirring for 2-3 hours, then ending the reaction, cooling to room temperature, discharging, and obtaining the polyurethane prepolymer component; The polyether polyol is polycaprolactone polyol and polypropylene polyol; the polypropylene polyol is one of polypropylene glycol PPG600, polypropylene glycol PPG800, polypropylene triol N303 and polypropylene triol N306; the polycaprolactone polyol is one of ethylene glycol-based polycaprolactone diol, glycerol-based polycaprolactone triol, trimethylolpropane-based polycaprolactone triol and pentaerythritol-based polycaprolactone tetraol; the isocyanate monomer is one or more of diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, toluene diisocyanate, isophorone diisocyanate and dicyclohexylmethane diisocyanate; The mass ratio of polypropylene polyol to polycaprolactone polyol in the polyether polyol is (3-4):(1-2); the mass ratio of the polyether polyol to isocyanate monomer is (4-5):(5-6).

2. The moisture-curing polyurethane adhesive according to claim 1, characterized in that: The curing accelerator is one or more of bismorpholinyl diethyl ether and dibutyltin dilaurate; the filler is one or more of nano-scale white carbon black, calcium oxide, and zinc oxide; the pigment is one or more of oily phthalocyanine blue, phthalocyanine green, carbon black, and iron red paste; and the dehydrating agent is one or more of methanesulfonic acid, maleic anhydride, itaconic anhydride, and molecular sieves.

3. A method for preparing the moisture-curing polyurethane adhesive according to any one of claims 1 to 2, characterized in that: The preparation method comprises the following steps: adding a polyurethane prepolymer component into a reaction kettle, passing nitrogen and heating to 50-60° C., then respectively adding fillers, pigments, dehydrating agents and defoaming agents, stirring evenly for 0.5 h, adding a curing accelerator, and continuing the reaction for 0.5 h to obtain a moisture-cured polyurethane adhesive, which can be sealed and stored.

4. An application of the moisture-curing polyurethane adhesive according to any one of claims 1 to 2, characterized in that: Specifically, the wet-curing polyurethane adhesive is coated on the glass fiber and applied to the medical field of preparing orthopedics, prosthetic auxiliary devices and supporting tools for plastic surgery, local protective stents for burns, and other emergency repair and reinforcement fields.

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