Anti-radiation acrylic acid modified waterborne polyurethane and preparation method thereof

Abstract

The invention discloses anti-radiation acrylic acid modified waterborne polyurethane, and belongs to the field of waterborne polyurethane preparation, the waterborne polyurethane is prepared from the following components by weight: polyester polyol, polyether polyol, diisocyanate, a catalyst, acetone, a coupling agent, an acrylate functional monomer, an initiator, a hydrophilic chain extender and deionized water, the invention relates to a waterborne polyurethane resin, which is prepared from the following raw materials in parts by weight: 10 to 15 parts of polycarbonate II, 5 to 10 parts of polyether polyol, 5 to 11 parts of diisocyanate, 0.002 to 0.005 part of catalyst, 15 to 20 parts of acetone, 0.5 to 1 part of coupling agent, 3 to 7 parts of acrylate functional monomer, 0.001 to 0.002 part of initiator, 5 to 8 parts of sulfonate hydrophilic compound serving as a hydrophilic chain extender and 50 to 56 parts of deionized water. The waterborne polyurethane has high solid content of 50%, excellent radiation resistance and storage stability.

Description

Technical Field

[0001] The invention belongs to the technical field of waterborne polyurethane, and particularly relates to an acrylic acid-modified waterborne polyurethane for radiation protection and a preparation method thereof. Background Art

[0002] With the rapid development of science and technology, the widespread use of electronic products has led to an increasingly serious problem of electromagnetic radiation pollution. In order to reduce the harm of electromagnetic radiation to the human body, the development of materials with radiation protection properties has become a research hotspot. Acrylic modified waterborne polyurethane (PUA) can achieve the complementary advantages of polyurethane and acrylic acid in performance due to its excellent environmental performance, film-forming properties and mechanical properties. However, traditional acrylic modified waterborne polyurethane still has certain limitations in terms of radiation protection performance.

[0003] In order to make acrylic modified waterborne polyurethane have better radiation protection performance, researchers have tried to introduce heavy metal compounds, such as zinc oxide, cadmium oxide, etc., into the polyurethane molecular chain to improve the radiation protection performance of the material. However, these heavy metal compounds may pollute the environment and pose potential risks to human health. There are also methods of adding rare earth solutions to obtain radiation protection performance in applications, such as the method disclosed in China Patent Authorization Announcement No.: CN110527423B, but this method is expensive and not conducive to mass production and application. In the synthesis of waterborne polyurethane, in order to simultaneously achieve the characteristics of participating in the polymerization reaction and having electromagnetic radiation protection, it is necessary to select functional monomers that can stably exist during the polymerization process and can effectively shield electromagnetic waves. The introduction of such functional monomers can not only directly participate in the formation of polyurethane chains during the polymerization process, but also enhance the material's ability to absorb and shield radiation.

[0004] Therefore, how to develop an environmentally friendly, efficient, and low-cost radiation-proof acrylic modified waterborne polyurethane is a problem that needs to be solved.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide an acrylic modified waterborne polyurethane for radiation protection and a preparation method thereof, which has the advantages of radiation protection, high solid content, excellent stability, strong adaptability and low cost, thereby solving the above-mentioned technical problems existing in the prior art.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] An acrylic acid-modified waterborne polyurethane for radiation protection is prepared from the following parts by weight of polyester polyol, polyether polyol, diisocyanate, catalyst, acetone, coupling agent, acrylate functional monomer, initiator, hydrophilic chain extender and deionized water:

[0009]

[0010] A method for preparing the acrylic acid-modified waterborne polyurethane for radiation protection according to the present invention comprises:

[0011] According to the formula of the present invention, various raw materials for preparing acrylic acid-modified waterborne polyurethane for radiation protection are taken;

[0012] Add the polycarbonate diol and polyether polyol in the raw materials into a container, and evacuate at 100°C for 1 hour; after cooling to 60°C, add diisocyanate and catalyst, heat to 80°C and react for 3 hours to obtain a prepolymer with an NCO content of 1.3-1.4%;

[0013] Acetone is added to the prepolymer in the container at a temperature of 65° C. to dilute and reduce the viscosity, a coupling agent is added to react for 20 minutes, an acrylate functional monomer and an initiator are added and slowly stirred to react for 30 minutes until the solution viscosity increases to 500 mPa·s, the temperature is lowered to 40° C., a sulfonate hydrophilic compound as a hydrophilic chain extender is added and stirred for 20 minutes, the prepolymer is transferred to a high-speed stirrer, deionized water is quickly added and stirred at a high speed for emulsification for 2 hours, and the acetone is removed by vacuum distillation to obtain an acrylic acid-modified waterborne polyurethane for radiation protection.

[0014] Compared with the prior art, the acrylic acid-modified waterborne polyurethane for radiation protection provided by the present invention and its preparation method have the following beneficial effects:

[0015] By adding polycarbonate diol, the carbonate bonds in the polycarbonate diol give the polyurethane excellent mechanical properties, hydrolysis resistance, heat resistance, chemical resistance and weather resistance. Adding a small amount of polyether polyol makes the polyurethane have better flexibility. Compared with carboxylates, the sulfonate hydrophilic compound added as a hydrophilic chain extender does not need to be neutralized by adding triethylamine, eliminating the odor and instability caused by the volatilization of triethylamine during storage. In addition, the sulfonate hydrophilic compound is a strong acid and strong base salt with a high ionization strength, which can form a strong electrostatic repulsion between latex particles and prevent the latex particles from agglomerating, thereby obtaining a high solid content and stable waterborne polyurethane. At the same time, the introduction of radiation protection functional units through the modification of acrylate functional monomers not only makes the waterborne polyurethane have good film-forming properties, adhesion and wear resistance, but also can form a uniform and dense radiation protection coating on the surface of various substrates, thereby improving the radiation protection performance of the material. Through acrylic acid modification, the mechanical properties of waterborne polyurethane are improved, making it have better tensile resistance, impact resistance and bending resistance. The waterborne polyurethane of the present invention has high initial adhesion and bonding strength, high solid content and strong stability. It belongs to a waterborne emulsion, has the advantages of environmental protection, non-toxicity, safety, low VOC, low odor, etc., and can be glued by spraying, roller coating, brushing and other methods. It has a wider application surface and is suitable for use as a main resin in the fields of radiation-proof waterborne polyurethane coatings or adhesives, etc., can meet the increasingly high radiation protection requirements, and has a wide application prospect. DETAILED DESCRIPTION

[0016] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in combination with the specific content of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, which does not constitute a limitation of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0017] First, the terms that may be used in this article are explained as follows:

[0018] The term “and / or” means that either or both of them can be realized at the same time. For example, X and / or Y means both “X” or “Y” and “X and Y”.

[0019] The terms "include", "comprises", "contains", "has" or other descriptions with similar semantics should be interpreted as non-exclusive inclusion. For example, including certain technical feature elements (such as raw materials, components, ingredients, carriers, dosage forms, materials, dimensions, parts, components, mechanisms, devices, steps, procedures, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products or products, etc.) should be interpreted as including not only certain technical feature elements explicitly listed, but also other technical feature elements known in the art that are not explicitly listed.

[0020] The term "consisting of..." means excluding any technical feature elements not explicitly listed. If this term is used in a claim, it will make the claim closed, so that it does not contain technical feature elements other than the technical feature elements explicitly listed, except for the conventional impurities related to them. If this term only appears in a clause of a claim, it only limits the elements explicitly listed in the clause, and the elements recorded in other clauses are not excluded from the overall claim.

[0021] The term "parts by mass" refers to the mass ratio relationship between multiple components. For example, if it is described that component X is x parts by mass and component Y is y parts by mass, then the mass ratio of component X to component Y is x:y. 1 part by mass can represent any mass, for example, 1 part by mass can be represented as 1 kg or 3.1415926 kg. The sum of the parts by mass of all components is not necessarily 100 parts, but can be greater than 100 parts, less than 100 parts or equal to 100 parts. Unless otherwise specified, the parts, proportions and percentages described herein are all measured by mass.

[0022] When concentration, temperature, pressure, size or other parameters are expressed in the form of a numerical range, the numerical range should be understood to specifically disclose all ranges formed by the pairing of any upper limit, lower limit, and preferred value in the numerical range, regardless of whether the range is explicitly stated; for example, if a numerical range of "2 to 8" is stated, the numerical range should be interpreted as including ranges such as "2 to 7", "2 to 6", "5 to 7", "3 to 4 and 6 to 7", "3 to 5 and 7", "2 and 5 to 7", etc. Unless otherwise specified, the numerical ranges stated herein include both their end values ​​and all integers and fractions within the numerical range.

[0023] The following is a detailed description of the acrylic acid modified waterborne polyurethane for radiation protection provided by the present invention and its preparation method. The contents not described in detail in the embodiments of the present invention belong to the prior art known to professionals in the field. If no specific conditions are specified in the embodiments of the present invention, the conditions are carried out according to the conventional conditions in the field or the conditions recommended by the manufacturer. If the manufacturers of the reagents or instruments used in the embodiments of the present invention are not specified, they are all conventional products that can be purchased commercially.

[0024] The embodiment of the present invention provides an acrylic modified waterborne polyurethane for radiation protection, which is a waterborne polyurethane dispersion. The waterborne polyurethane is made of the following parts by weight of polyester polyol, polyether polyol, diisocyanate, catalyst, acetone as a solvent, coupling agent, acrylate functional monomer, initiator, hydrophilic chain extender and deionized water:

[0025]

[0026] In some specific embodiments of the present invention, the polycarbonate diol can be any one or any two of DURANOL G4672, DURANOL G3452, DURANOL GE501, and DURANOL T5650J, and the average molecular weight is 500-2000.

[0027] In some specific embodiments of the present invention, the sulfonate hydrophilic compound used as the hydrophilic chain extender can be one of sodium ethylenediamine ethanesulfonate and sulfonate BY-3306B (Baiyuan Chemical).

[0028] In some specific embodiments of the present invention, the polyether polyol can be any one or any two of polytetrahydrofuran, polycastor oil adipate polyol, and polytetramethylene ether glycol, and the average molecular weight is 1000-3000.

[0029] In some specific embodiments of the present invention, the diisocyanate may be any one or more of isophorone diisocyanate, diphenylmethane diisocyanate and hexamethylene diisocyanate.

[0030] In some specific embodiments of the present invention, the catalyst may be at least one of dibutyltin dilaurate and an organic bismuth catalyst 83 .

[0031] In some specific embodiments of the present invention, the coupling agent may be at least one of 3-diethylenetriaminopropyltrimethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane and 3-diethylenetriaminopropylmethyldimethoxysilane.

[0032] In some specific embodiments of the present invention, the acrylate functional monomer may be at least one of zinc methacrylate, barium methacrylate, iron methacrylate, and lead methacrylate.

[0033] In some specific embodiments of the present invention, the initiator is azobisisobutyronitrile.

[0034] The present invention also provides a method for preparing an acrylic acid-modified waterborne polyurethane for radiation protection, which is used to prepare the acrylic acid-modified waterborne polyurethane for radiation protection, and specifically may include the following steps:

[0035] Add polycarbonate diol and polyether polyol into a container, and evacuate at 100°C for 1 hour; after cooling to 60°C, add diisocyanate and catalyst, heat to 80°C and react for 3 hours to obtain a prepolymer with an NCO content of 1.3-1.4%;

[0036] Acetone was added to the prepolymer in the container at 65° C. to dilute and reduce viscosity, a coupling agent was added to react for 20 min, an acrylate functional monomer and an initiator were added and slowly stirred for reaction for 30 min until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., a hydrophilic chain extender was added and stirred for 20 min, the prepolymer was transferred to a high-speed stirrer, deionized water was quickly added and stirred at high speed for emulsification for 2 h, and the acetone was removed by vacuum distillation to obtain an acrylic acid-modified waterborne polyurethane for radiation protection.

[0037] In summary, the method for preparing the radiation-proof acrylic acid-modified waterborne polyurethane provided by the present invention has at least the following advantages:

[0038] (1) The present invention uses polycarbonate diol, polyether polyol and isocyanate in a specific ratio. The carbonate bonds in the polycarbonate diol give the polyurethane excellent mechanical properties, hydrolysis resistance, heat resistance, chemical resistance and weather resistance. A small amount of polyether makes the polyurethane have good flexibility. The water-based polyurethane dispersion has a high initial adhesion and bonding strength, and the substrate will not fall off or separate during the application process.

[0039] (2) The present invention uses a sulfonate hydrophilic compound as a hydrophilic chain extender. Compared with carboxylic acid-containing PUD or sulfonic acid / carboxylic acid PUD, it does not need to add triethylamine for neutralization, thereby eliminating the odor and instability caused by the volatilization of triethylamine during storage. In addition, sulfonate is a strong acid and strong base salt with a high ionization strength, which can form a strong electrostatic repulsion between latex particles and prevent the latex particles from agglomerating, thereby obtaining a high solid content and stable waterborne polyurethane. It can effectively avoid accidents such as phase separation, odor, and bottle swelling during storage of the product.

[0040] (3) The present invention introduces a radiation protection functional unit through acrylic acid modification, which not only enables the dispersion to have good film-forming properties, adhesion and wear resistance, but also can form a uniform and dense radiation protection coating on the surface of various substrates, thereby improving the radiation protection performance of the material. The mechanical properties of the waterborne polyurethane are improved through acrylic acid modification, so that it has better tensile resistance, impact resistance and bending resistance.

[0041] (4) The aqueous polyurethane dispersion prepared by the present invention is an aqueous emulsion, which has the advantages of being environmentally friendly, non-toxic, safe, low VOC, and low odor. It can effectively avoid the shortcomings of anaerobic adhesives such as strong odor and flammability, and can be glued by spraying, roller coating, brushing, etc. It has a wider range of applications and is suitable for use as a main resin in fields such as aqueous polyurethane coatings or adhesives that require radiation protection.

[0042] In order to more clearly demonstrate the technical solution and technical effects provided by the present invention, the preparation method of the acrylic modified waterborne polyurethane for radiation protection provided by the embodiment of the present invention is described in detail with specific examples below.

[0043] Example 1

[0044] This embodiment provides a method for preparing an acrylic acid-modified waterborne polyurethane for radiation protection, wherein each component is calculated by weight and comprises the following steps:

[0045] 10 parts of polycarbonate diol G3452 and 7 parts of polytetrahydrofuran were added into a container, and vacuum was applied at 100° C. for 1 hour; after cooling to 60° C., 8 parts of isophorone diisocyanate and 0.002 parts of organic bismuth catalyst 83 were added, and the temperature was raised to 80° C. for reaction for 3 hours to obtain a prepolymer with an NCO content of 1.34%;

[0046] At a temperature of 65° C., 20 parts of acetone were added to the prepolymer in the container to dilute and reduce viscosity, 0.5 parts of 3-diethylenetriaminopropyltrimethoxysilane was added to react for 20 minutes, 6 parts of barium methacrylate and 0.0015 parts of initiator were added and slowly stirred for reaction for 30 minutes until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., 6 parts of sodium ethylenediaminesulfonate were added and stirred for 20 minutes, the prepolymer was transferred to a high-speed stirrer, 55 parts of deionized water were quickly added and stirred at a high speed for emulsification for 2 hours, and the acetone was removed by vacuum distillation to obtain an acrylic modified waterborne polyurethane for radiation protection.

[0047] The dispersion was formed into a film, and the tensile strength was tested to be 20.16MPa, the elongation at break was 1369%, and the electromagnetic shielding effectiveness test value was 32dB. According to the national standard GB / T2791-1995, the maximum peel strength was 207.34N / mm, and the substrate was completely peeled off. The stable storage period is more than 6 months.

[0048] Example 2

[0049] This embodiment provides a method for preparing an acrylic acid-modified waterborne polyurethane for radiation protection, wherein each component is calculated by weight and comprises the following steps:

[0050] 15 parts of polycarbonate diol T5650J and 5 parts of polytetramethylene ether glycol were added into a container, and vacuum was applied at 100° C. for 1 hour; after cooling to 60° C., 10 parts of hexamethylene diisocyanate and 0.002 parts of organic bismuth catalyst 83 were added, and the temperature was raised to 80° C. for reaction for 3 hours to obtain a prepolymer with an NCO content of 1.34%;

[0051] At a temperature of 65° C., 20 parts of acetone were added to the prepolymer in the container to dilute and reduce viscosity, 0.8 parts of 3-diethylenetriaminopropylmethyldimethoxysilane was added to react for 20 minutes, 5 parts of zinc methacrylate and 0.0015 parts of initiator were added to slowly stir and react for 30 minutes until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., 7 parts of sodium ethylenediaminesulfonate were added to stir for 20 minutes, the prepolymer was transferred to a high-speed stirrer, 56 parts of ionized water were quickly added to stir and emulsify at a high speed for 2 hours, and the acetone was removed by vacuum distillation to obtain an acrylic modified waterborne polyurethane for radiation protection.

[0052] The dispersion was formed into a film, and the tensile strength was tested to be 21.89MPa, the elongation at break was 1023%, and the electromagnetic shielding effectiveness test value was 26dB. According to the national standard GB / T2791-1995, the maximum peel strength was 215.77N / mm, and the substrate was completely peeled off. The stable storage period exceeded 6 months.

[0053] Example 3

[0054] This embodiment provides a method for preparing an acrylic acid-modified waterborne polyurethane for radiation protection, wherein each component is calculated by weight and comprises the following steps:

[0055] 12 parts of polycarbonate diol GE501 and 10 parts of polycastor oil adipate polyol were added into a container, and vacuum was applied at 100° C. for 1 hour; after cooling to 60° C., 11 parts of hexamethylene diisocyanate and 0.002 parts of dibutyltin dilaurate were added, and the temperature was raised to 80° C. and reacted for 3 hours to obtain a prepolymer with an NCO content of 1.4%;

[0056] At a temperature of 65° C., 15 parts of acetone were added to the prepolymer in the container to dilute and reduce the viscosity, 1 part of N-2-aminoethyl-3-aminopropyltriethoxysilane was added to react for 20 minutes, 7 parts of lead methacrylate and 0.002 parts of initiator were added and slowly stirred for reaction for 30 minutes until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., 6 parts of sulfonate BY-3306B were added and stirred for 20 minutes, the mixture was transferred to a high-speed stirrer, 55 parts of deionized water were quickly added and stirred at a high speed for emulsification for 2 hours, and the acetone was removed by vacuum distillation to obtain an acrylic modified waterborne polyurethane for radiation protection.

[0057] The dispersion was formed into a film, and the tensile strength was tested to be 23.45MPa, the elongation at break was 963.21%, and the electromagnetic shielding effectiveness test value was 36dB. According to the national standard GB / T2791-1995, the maximum peel strength was 221.74N / mm, and the substrate was completely peeled off. The stable storage period is more than 6 months.

[0058] Example 4

[0059] This embodiment provides a method for preparing an acrylic acid-modified waterborne polyurethane for radiation protection, wherein each component is calculated by weight and comprises the following steps:

[0060] 6 parts of polycarbonate diol G4672, 6 parts of polycarbonate diol GE501, and 6 parts of polycastor oil adipate polyol were added into a container, and vacuumed at 100° C. for 1 hour; after cooling to 60° C., 10 parts of diphenylmethane diisocyanate and 0.002 parts of dibutyltin dilaurate were added, and the temperature was raised to 80° C. and reacted for 3 hours to obtain a prepolymer with an NCO content of 1.3%;

[0061] At a temperature of 65° C., 20 parts of acetone were added to the prepolymer in the container to dilute and reduce viscosity, 1 part of 3-diethylenetriaminopropyltrimethoxysilane was added to react for 20 minutes, 5 parts of zinc methacrylate and 0.001 parts of initiator were added and slowly stirred for reaction for 30 minutes until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., 7 parts of sodium ethylenediaminesulfonate were added and stirred for 20 minutes, the prepolymer was transferred to a high-speed stirrer, 55 parts of deionized water were quickly added and stirred at a high speed for emulsification for 2 hours, and the acetone was removed by vacuum distillation to obtain an acrylic modified waterborne polyurethane for radiation protection.

[0062] The dispersion was formed into a film, and the tensile strength was tested to be 25.22MPa, the elongation at break was 944.56%, and the electromagnetic shielding effectiveness test value was 27dB. According to the national standard GB / T2791-1995, the maximum peel strength was 233.45N / mm, and the substrate was completely peeled off. The stable storage period is more than 6 months.

[0063] Example 5

[0064] This embodiment provides a method for preparing an acrylic acid-modified waterborne polyurethane for radiation protection, wherein each component is calculated by weight and comprises the following steps:

[0065] 12 parts of polycarbonate diol GE501 and 6 parts of polytetramethylene diol were added into a container, and vacuumed at 100° C. for 1 hour; after cooling to 60° C., 5 parts of isophorone diisocyanate, 5 parts of hexamethylene diisocyanate and 0.002 parts of dibutyltin dilaurate were added, and the temperature was raised to 80° C. and reacted for 3 hours to obtain a prepolymer with an NCO content of 1.35%;

[0066] At a temperature of 65° C., 20 parts of acetone were added to the prepolymer in the container to dilute and reduce viscosity, 0.7 parts of N-2-aminoethyl-3-aminopropyltriethoxysilane was added to react for 20 minutes, 6 parts of barium methacrylate and 0.002 parts of initiator were added to slowly stir and react for 30 minutes until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., 8 parts of sodium ethylenediaminesulfonate were added to stir for 20 minutes, the prepolymer was transferred to a high-speed stirrer, 55 parts of deionized water were quickly added to stir and emulsify at a high speed for 2 hours, and the acetone was removed by vacuum distillation to obtain an acrylic modified waterborne polyurethane for radiation protection.

[0067] The dispersion was formed into a film, and the tensile strength was tested to be 24.33MPa, the elongation at break was 948.58%, and the electromagnetic shielding effectiveness test value was 28dB. According to the national standard GB / T2791-1995, the maximum peel strength was 237.79N / mm, and the substrate was completely peeled off. The stable storage period exceeded 6 months.

[0068] Comparative Example 1

[0069] This comparative example does not belong to the prior art. It is only to determine the effect of changes in certain components and dosages on the performance of the product of the present invention. On the basis of the scheme of the present invention, some components and dosages are adjusted to obtain a scheme. Each component is calculated by weight and includes:

[0070] 10 parts of polycarbonate diol G3452 and 7 parts of polytetrahydrofuran were added into a container, and vacuum was applied at 100° C. for 1 hour; after cooling to 60° C., 8 parts of isophorone diisocyanate and 0.002 parts of organic bismuth catalyst 83 were added, and the temperature was raised to 80° C. and reacted for 3 hours to obtain a prepolymer with an NCO content of 1.34%;

[0071] At a temperature of 65° C., 20 parts of acetone were added to the prepolymer in the container to dilute and reduce the viscosity, 0.5 parts of 3-diethylenetriaminopropyltrimethoxysilane was added to react for 20 minutes, 6 parts of methyl methacrylate and 0.0015 parts of initiator were added to slowly stir and react for 30 minutes until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., 6 parts of sodium ethylenediaminesulfonate were added to stir for 20 minutes, the prepolymer was transferred to a high-speed stirrer, 55 parts of deionized water were quickly added to stir and emulsify at a high speed for 2 hours, and the acetone was removed by vacuum distillation to obtain the radiation-proof acrylic modified waterborne polyurethane.

[0072] Compared with Examples 1 to 5, the acrylate functional monomer in the system is replaced with methyl methacrylate, and the formula is a more common acrylic modified waterborne polyurethane. After film formation, the tensile strength is 19.23MPa, the elongation at break is 1221%, and the electromagnetic shielding effectiveness test value is 6dB, and the electromagnetic shielding effect is poor. According to the national standard GB / T2791-1995, the maximum peel strength of T is 211.47N / mm, and the substrate is completely peeled off. The stable storage period exceeds 6 months.

[0073] Comparative Example 2

[0074] This comparative example does not belong to the prior art. It is only to determine the effect of changes in certain components and dosages on the performance of the product of the present invention. On the basis of the scheme of the present invention, some components and dosages are adjusted to obtain a scheme. Each component is calculated by weight and includes:

[0075] 16 parts of polycarbonate diol G345 were added into a container and vacuumed at 100° C. for 1 hour; after cooling to 60° C., 8 parts of isophorone diisocyanate and 0.002 parts of organic bismuth catalyst 83 were added, and the temperature was raised to 80° C. and reacted for 3 hours to obtain a prepolymer with an NCO content of 1.34%;

[0076] At a temperature of 65° C., 20 parts of acetone were added to the prepolymer in the container to dilute and reduce viscosity, 0.5 parts of 3-diethylenetriaminopropyltrimethoxysilane was added to react for 20 minutes, 6 parts of methyl methacrylate and 0.0015 parts of initiator were added to slowly stir and react for 30 minutes until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., 6 parts of sodium ethylenediaminesulfonate were added to stir for 20 minutes, the prepolymer was transferred to a high-speed stirrer, 55 parts of deionized water were quickly added to stir and emulsify at a high speed for 2 hours, and the acetone was removed by vacuum distillation to obtain the radiation-proof acrylic modified waterborne polyurethane.

[0077] Compared with Example 1, only polycarbonate diol is used as the soft segment, the tensile strength is improved, but the elongation at break is significantly reduced, and the cost is increased. After film formation, the tensile strength is 27.68MPa, the elongation at break is 672%, and the electromagnetic shielding effectiveness test value is 32dB. According to the national standard GB / T2791-1995, the maximum peel strength of T is 232.57N / mm, and the substrate is completely peeled off. The stable storage period exceeds 6 months.

[0078] Comparative Example 3

[0079] This comparative example does not belong to the prior art. It is only to determine the effect of changes in certain components and dosages on the performance of the product of the present invention. On the basis of the scheme of the present invention, some components and dosages are adjusted to obtain a scheme. Each component is calculated by weight and includes:

[0080] 10 parts of polycarbonate diol G3452 and 7 parts of polytetrahydrofuran were added into a container, and vacuum was applied at 100° C. for 1 hour; after cooling to 60° C., 8 parts of isophorone diisocyanate and 0.002 parts of organic bismuth catalyst 83 were added, and the temperature was raised to 80° C. and reacted for 3 hours to obtain a prepolymer with an NCO content of 1.34%;

[0081] At a temperature of 65° C., 20 parts of acetone were added to the prepolymer in the container to dilute and reduce viscosity, 0.5 parts of 3-diethylenetriaminopropyltrimethoxysilane was added to react for 20 minutes, 6 parts of barium methacrylate and 0.0015 parts of initiator were added and slowly stirred for reaction for 30 minutes until the solution viscosity increased to 500 mPa·s, the temperature was lowered to 40° C., 3 parts of sodium ethylenediaminesulfonate were added and stirred for 20 minutes, the prepolymer was transferred to a high-speed stirrer, 55 parts of deionized water were quickly added and stirred at a high speed for emulsification for 2 hours, and the acetone was removed by vacuum distillation to obtain the radiation-proof acrylic modified waterborne polyurethane.

[0082] Compared with Example 1, the amount of hydrophilic chain extender added was reduced, the hydrophilic group content was reduced, the particle size of the dispersion was increased, and the storage, dilution and centrifugal stability were reduced, affecting the subsequent test and use. The stable storage period was less than 6 months.

[0083] In summary, the waterborne polyurethane of the present invention has a high solid content of 50% and has excellent radiation protection performance and storage stability.

[0084] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed in the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims. The information disclosed in the background technology section of this article is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as an admission or in any form that the information constitutes prior art known to those skilled in the art.

Claims

1. An acrylic acid-modified waterborne polyurethane for radiation protection, characterized in that: The waterborne polyurethane is prepared from the following parts by weight of polyester polyol, polyether polyol, diisocyanate, catalyst, acetone, coupling agent, acrylate functional monomer, initiator, hydrophilic chain extender and deionized water:

2. The acrylic acid-modified waterborne polyurethane for radiation protection according to claim 1, characterized in that: The polycarbonate diol is any one or any two of DURANOL G4672, DURANOL G3452, DURANOL GE501 and DURANOL T5650J, and the average molecular weight is 500-2000.

3. The acrylic acid-modified waterborne polyurethane for radiation protection according to claim 1, characterized in that: The sulfonate hydrophilic compound used as the hydrophilic chain extender is one of sodium ethylenediamine ethanesulfonate and sulfonate BY-3306B.

4. The acrylic acid-modified waterborne polyurethane for radiation protection according to any one of claims 1 to 3, characterized in that: The polyether polyol is any one or any two of polytetrahydrofuran, polycastor oil adipate polyol and polytetramethylene ether glycol, and the average molecular weight is 1000-3000.

5. The acrylic acid-modified waterborne polyurethane for radiation protection according to any one of claims 1 to 3, characterized in that: The diisocyanate is any one or more of isophorone diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate.

6. The acrylic acid-modified waterborne polyurethane for radiation protection according to any one of claims 1 to 3, characterized in that: The catalyst is at least one of dibutyltin dilaurate and an organic bismuth catalyst 83.

7. The strong adhesive and heat-resistant transparent aqueous polyurethane dispersion according to any one of claims 1 to 3, characterized in that: The coupling agent is at least one of 3-diethylenetriaminopropyltrimethoxysilane, N-2-aminoethyl-3-aminopropyltriethoxysilane and 3-diethylenetriaminopropylmethyldimethoxysilane.

8. The acrylic acid-modified waterborne polyurethane for radiation protection according to any one of claims 1 to 3, characterized in that: The acrylate functional monomer is at least one of zinc methacrylate, barium methacrylate, iron methacrylate and lead methacrylate.

9. The acrylic acid-modified waterborne polyurethane for radiation protection according to any one of claims 1 to 3, characterized in that: The initiator is azobisisobutyronitrile.

10. A method for preparing the acrylic acid-modified waterborne polyurethane for radiation protection according to any one of claims 1 to 9, characterized in that: include: The raw materials for preparing acrylic modified waterborne polyurethane for radiation protection are prepared according to the formula described in any one of claims 1 to 9; Add the polycarbonate diol and polyether polyol in the raw materials into a container, and evacuate at 100°C for 1 hour; after cooling to 60°C, add diisocyanate and catalyst, heat to 80°C and react for 3 hours to obtain a prepolymer with an NCO content of 1.3-1.4%; Acetone is added to the prepolymer in the container at a temperature of 65° C. to dilute and reduce the viscosity, a coupling agent is added to react for 20 minutes, an acrylate functional monomer and an initiator are added and slowly stirred to react for 30 minutes until the solution viscosity increases to 500 mPa·s, the temperature is lowered to 40° C., a sulfonate hydrophilic compound as a hydrophilic chain extender is added and stirred for 20 minutes, the prepolymer is transferred to a high-speed stirrer, deionized water is quickly added and stirred at a high speed for emulsification for 2 hours, and the acetone is removed by vacuum distillation to obtain an acrylic acid-modified waterborne polyurethane for radiation protection.

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