A modified castor oil polyurethane adhesive containing catalytic groups, its preparation method and application
By introducing quaternary ammonium salt groups into modified castor oil polyurethane adhesive, the problems of toxicity, corrosivity and migration of traditional catalysts are solved, achieving efficient and safe catalytic effects and good adhesive performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- YANTAI RUILONG CHEM TECH CO LTD
- Filing Date
- 2026-01-14
- Publication Date
- 2026-05-26
AI Technical Summary
Existing polyurethane catalysts suffer from problems such as toxicity, corrosiveness, easy migration, and irritating odor, which affect their application areas and performance.
Modified castor oil polyurethane adhesive containing quaternary ammonium salt groups is used. By introducing -NH3Cl, -NH2 and -OH groups on the molecular chain, the Lewis acidity and ion pair effect are utilized to activate the reactive groups, stabilize the reaction transition state, and avoid migration and corrosion.
It achieves highly efficient catalytic reaction between -OH and -NCO, improves reaction efficiency, endows adhesives with good thixotropic properties and high strength, and is safe and environmentally friendly, avoiding the toxic side effects and migration problems of traditional catalysts.
Smart Images
Figure CN121495522B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of organic polymer adhesive technology, specifically relating to a modified castor oil polyurethane adhesive containing catalytic groups, its preparation method, and its application. Background Technology
[0002] Polyurethane is a high-performance polymer material that is usually derived from the reaction of hydroxyl (-OH) components and isocyanate (-NCO) components. It is widely used in many fields such as thermoplastic elastomers, foamed insulation materials, coatings, adhesives and inks.
[0003] To regulate the addition reaction rate of -OH and -NCO and control the structure of the products, catalysts such as organometallic compounds, tertiary amines, and organic acids are often added. Transition organometallic catalysts (e.g., dibutyltin dilaurate) have transition metal atoms that directly coordinate with -NCO, resulting in strong activation effects with small addition amounts. However, most organometallic catalysts are toxic, limiting their application. Tertiary amine catalysts (e.g., pentamethyldiethylenetriamine) are strongly basic and enhance the reactivity of -NCO by attracting electrons from the carbonyl carbon of isocyanates. Tertiary amine catalysts are diverse, low-cost, and have strong catalytic activity for gelation and foaming; however, they have an irritating odor and are volatile. Organic and inorganic acids (e.g., succinic acid and phosphoric acid) can both be used as catalysts for polyurethanes due to their high catalytic activity and fast reaction rates, and are widely used in polyurethane synthesis. However, acidic substances readily ionize to release H₂. + Ions can be corrosive to metal equipment or molds. Furthermore, although organometallic, tertiary amine, and organic acid catalysts exhibit good catalytic effects on the reactions of -OH and -NCO, and have been successfully applied in the production of various polyurethane products, most traditional polyurethane catalysts have small molecular weights, are prone to migration, and possess certain toxic side effects. Summary of the Invention
[0004] The purpose of this invention is to address the shortcomings of the prior art by providing a modified castor oil polyurethane adhesive containing catalytic groups, its preparation method, and its application. The modified castor oil molecular chain simultaneously contains quaternary ammonium salts (-NH3Cl), -NH2, and -OH groups. -NH3Cl can efficiently catalyze the reaction between -OH and -NCO, improving reaction efficiency; the -NH2 and -OH groups react with -NCO, imparting excellent thixotropic properties and high strength to the adhesive.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] The first aspect of the present invention is to provide a modified castor oil polyurethane adhesive containing a catalytic group. The adhesive is a two-component adhesive, wherein, by weight, component A comprises 30.0-50.0 parts of modified castor oil and 0.0-30.0 parts of refined castor oil; component B comprises 30.0-50.0 parts of polyisocyanate or polyisocyanate modifier and 0.00-0.05 parts of dehydrating agent.
[0007] The method for preparing the modified castor oil includes the following steps:
[0008] S1. Add a mixture of refined castor oil and cysteine hydrochloride at a molar ratio of 1:3, and add 3-8% of photoinitiator and methanol of cysteine hydrochloride. Stir to obtain a reaction solution with a mass concentration of 25-40%.
[0009] S2. Under high-purity nitrogen atmosphere, stirring, room temperature and ultraviolet light irradiation conditions, react for 6~24 h to obtain product solution;
[0010] S3. Add a strong base less than three times the molar amount of castor oil and continue stirring at room temperature for a period of time. After removing methanol from the product solution using a rotary evaporator, add chloroform, wash with deionized water, separate the layers, and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. Dry to constant weight to obtain the modified castor oil product.
[0011] Furthermore, the molecular structural formula of the modified castor oil is as follows: , where R= Or R = .
[0012] Furthermore, the structural formula of the diisocyanate is as follows: (IPDI) (HMDI) (MDI) (HDI) (TDI) (TDI) (TMXDI) (XDI) (TMDI) or At least one of (TMDI).
[0013] Furthermore, the polyisocyanate and the polyisocyanate modifier are at least one of TDI trimer, HDI trimer, IPDI trimer, polyphenyl polymethylene polyisocyanate (PAPI), PM-200 (Yantai Wanhua), NT-8075 (Wuhan Shiquanxing), S-325 (Wuhan Shiquanxing) or S-310 (Wuhan Shiquanxing).
[0014] Furthermore, the photoinitiator is at least one selected from the following: benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropylthioxanthone, benzophenone, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, α,α'-diethoxyacetophenone, ethyl 4-(N,N-dimethylamino)benzoate, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, methyl o-benzoylformate, methyl o-benzoylbenzoate, or ethyl 2,4,6-trimethylbenzoylphenylphosphonate.
[0015] Furthermore, the strong base is at least one of sodium methoxide, sodium hydroxide, and strong potassium oxide.
[0016] Furthermore, the dehydrating agent is at least one of p-toluenesulfonyl isocyanate, 3-ethyl-2-methyl-2-(3-methylbutyl)-1,3-oxazolidine, 3-butyl-2-(1-ethylpentyl)oxazolidine, and 2-methyl-2-ethyl-3-hydroxyethyl-1,3-oxazolidine.
[0017] A second aspect of the present invention is to provide a method for preparing the above-mentioned polyurethane adhesive, wherein the preparation method comprises preparing the following components in parts by weight:
[0018] Component A includes 30.0~50.0 parts of modified castor oil and 0.0~30.0 parts of refined castor oil; Component B includes 30.0~50.0 parts of polyisocyanate or polyisocyanate modifier and 0.00~0.05 parts of dehydrating agent.
[0019] At room temperature, component A is mixed, degassed under vacuum, and then filled into packaging and sealed. Component B is mixed, degassed under vacuum at room temperature, filled into packaging, and sealed to obtain polyurethane adhesive.
[0020] A third aspect of the present invention is to provide the application of the above-described polyurethane adhesive in the packaging and assembly process of new energy batteries.
[0021] Compared with the prior art, the beneficial effects of the technical solution provided by the present invention are:
[0022] (1) High catalytic activity and safe and environmentally friendly. The quaternary ammonium salt groups on the molecular chain activate the reactive groups and stabilize the reaction transition state through their Lewis acidity and ion pair effect, thus catalyzing the reaction of -NCO and -OH. Compared with other types of quaternary ammonium salts, the steric hindrance around the nitrogen atom in -NH3Cl is small, which does not affect the proximity of -OH and -NCO. In terms of spatial structure, -NH3Cl is connected to flexible thioether bonds around -OH, making -NH3Cl easier to move and activate the reactive groups. In addition, compared with traditional transition metal catalysts such as organotin, quaternary ammonium salts have less toxic side effects and are safer and more environmentally friendly.
[0023] (2) The -NH3Cl group will enter the cross-linking network without migration. All -NH3Cl groups are attached to the castor oil molecular chain. As the -NCO and -OH reactions proceed, the quaternary ammonium salt functional groups enter the polyurethane adhesive network and will not migrate out of the adhesive due to molecular thermal motion.
[0024] (3) -NH3Cl has moderate acidity and alkalinity, unlike the strongly alkaline tetramethylammonium hydroxide which catalyzes the dimerization or trimerization of isocyanate groups and consumes some NCO, affecting the molar ratio of -OH to -NCO.
[0025] (4) The content of NH3Cl in modified castor oil can be adjusted by the amount of strong alkali added during the neutralization reaction, thereby controlling the catalytic activity and adjusting the reaction rate and crosslinking degree of the polyurethane adhesive. Attached Figure Description
[0026] Figure 1 Infrared spectra of the modified castor oil and refined castor oil prepared in Example 1;
[0027] Figure 2 Infrared spectra of modified castor oil and refined castor oil prepared in Comparative Example 2;
[0028] Figure 3 The DSC curves for the samples of Example 1 and Comparative Example 1 are shown.
[0029] Figure 4 The shear tensile curves are for the bonded specimens of Example 1 and Comparative Example 1. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the specific embodiments and accompanying drawings are described in further detail below. Where specific test methods, instruments, or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.
[0031] This invention provides a method for preparing a modified castor oil polyurethane adhesive containing catalytic groups. The preparation method comprises, by weight, the following components: 30.0-50.0 parts of modified castor oil, 0.0-30.0 parts of refined castor oil, 30.0-50.0 parts of polyisocyanate or polyisocyanate modifier, and 0.00-0.05 parts of dehydrating agent.
[0032] Modified castor oil is degassed under vacuum at room temperature, then filled into packaging materials and sealed; polyisocyanate or polyisocyanate modifier is mixed with dehydrating agent at room temperature, degassed under vacuum, filled into packaging materials, and sealed to obtain polyurethane adhesive.
[0033] The preparation method of modified castor oil includes the following steps:
[0034] S1. Add a mixture of refined castor oil and cysteine hydrochloride at a molar ratio of 1:3, and add 3-8% of photoinitiator and methanol of cysteine hydrochloride. Stir to obtain a reaction solution with a mass concentration of 25-40%.
[0035] S2. Under high-purity nitrogen atmosphere, stirring, room temperature and ultraviolet light irradiation conditions, react for 6~24 h to obtain product solution;
[0036] S3. Add 1.5 to 3 times the molar amount of strong base to the castor oil and continue stirring at room temperature for 1 h. After removing methanol from the product solution using a rotary evaporator, add 10 times the volume of chloroform to the product solution. Wash the product three times with an equal volume of deionized water, separate the layers, and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. This product is then dried in a vacuum drying oven at 40°C until constant weight to obtain the modified castor oil.
[0037] The molecular structural formula of modified castor oil is as follows: , where R= Or R = And R is The number is 1;
[0038] The structural formula of polyisocyanate is (IPDI) (HMDI) (MDI) (HDI) (TDI) (TDI) (TMXDI) (XDI) (TMDI) or At least one of (TMDI);
[0039] The polyisocyanate modifier is at least one of TDI trimer, HDI trimer, IPDI trimer, polyphenyl polymethylene polyisocyanate (PAPI), PM-200 (Yantai Wanhua), NT-8075 (Wuhan Shiquanxing), S-325 (Wuhan Shiquanxing) or S-310 (Wuhan Shiquanxing);
[0040] The initiator is at least one of the following: benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropylthioxanthone, benzophenone, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, α,α'-diethoxyacetophenone, ethyl 4-(N,N-dimethylamino)benzoate, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, methyl o-benzoylformate, methyl o-benzoylbenzoate, or ethyl 2,4,6-trimethylbenzoylphenylphosphonate.
[0041] The strong alkali mentioned is at least one of sodium methoxide, sodium hydroxide, and potassium hydroxide;
[0042] The dehydrating agent is at least one of p-toluenesulfonyl isocyanate, 3-ethyl-2-methyl-2-(3-methylbutyl)-1,3-oxazolidine, 3-butyl-2-(1-ethylpentyl)oxazolidine, and 2-methyl-2-ethyl-3-hydroxyethyl-1,3-oxazolidine.
[0043] The modified castor oil-based polyurethane adhesive provided by this invention can be prepared by following the above methods. Specific examples are described below.
[0044] Example 1
[0045] This embodiment provides a method for preparing a modified castor oil polyurethane adhesive containing catalytic groups, as detailed below:
[0046] S1. 10.00 g (10.5 mmol) of refined castor oil (hydroxyl value 36.86 mgKOH / 100g, iodine value 80 g / 100g), 3.58 g (31.5 mmol) of cysteine hydrochloride, and 0.1557 g (0.95 mmol) of 2-hydroxy-2-methyl-1-phenyl-1-propanone were added sequentially to a single-necked round-bottom flask, followed by the addition of 20.65 g of methanol. The mixture was stirred to obtain a reaction solution with a mass concentration of 40%.
[0047] S2. Under high-purity nitrogen atmosphere, stirring at room temperature and ultraviolet light irradiation, the reaction was carried out for 24 h to obtain the product solution;
[0048] S3. Add sodium hydroxide in 1.5 molar amounts as castor oil and continue stirring at room temperature for 1 h. After removing methanol from the product solution using a rotary evaporator, add chloroform in 10 times the volume of methanol. Wash three times with deionized water of equal volume as chloroform, separate the layers, and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. Place it in a vacuum drying oven at 40℃ and dry to constant weight to obtain the modified castor oil product.
[0049] 30.00 g of modified castor oil was degassed under vacuum, then filled into packaging materials and sealed to obtain polyurethane adhesive component A; at room temperature, 30.00 g of HDI trimer was mixed with 0.006 g of 3-ethyl-2-methyl-2-(3-methylbutyl)-1,3-oxazolidine, degassed under vacuum, filled into packaging materials, and sealed to obtain polyurethane adhesive component B.
[0050] Comparative Example 1
[0051] 30.00 g of refined castor oil was degassed under vacuum, then filled into packaging materials and sealed to obtain polyurethane adhesive component A; at room temperature, 15.00 g of HDI trimer was mixed with 0.003 g of 3-ethyl-2-methyl-2-(3-methylbutyl)-1,3-oxazolidine, degassed under vacuum, filled into packaging materials, and sealed to obtain polyurethane adhesive component B.
[0052] Comparative Example 2
[0053] This embodiment provides a method for preparing a modified castor oil polyurethane adhesive containing catalytic groups, as detailed below:
[0054] S1. 10.00 g (10.5 mmol) of refined castor oil (hydroxyl value 36.86 mgKOH / 100g, iodine value 80 g / 100g), 3.58 g (31.5 mmol) of cysteine hydrochloride, and 0.6458 g (2.52 mmol) of benzoin dimethyl ether were added sequentially to a single-necked round-bottom flask, and 42.68 g of methanol was added. The mixture was stirred to obtain a reaction solution with a mass concentration of 25%.
[0055] S2. Under high-purity nitrogen atmosphere, stirring at room temperature and ultraviolet light irradiation, the reaction was carried out for 12 h to obtain the product solution;
[0056] S3. Add sodium methoxide in 3 molar amounts as castor oil and continue stirring at room temperature for 1 h. After removing methanol from the product solution using a rotary evaporator, add chloroform in 10 times the volume of methanol. Wash three times with deionized water in equal volumes as chloroform, separate the layers, and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. Place it in a vacuum drying oven at 40℃ and dry to constant weight to obtain the modified castor oil product.
[0057] 50.00 g of modified castor oil and 10.0 g of refined castor oil were mixed, degassed under vacuum, and then filled into packaging materials and sealed to obtain polyurethane adhesive component A. At room temperature, 33.00 g of PM-200, 17.00 g of TDI and 0.05 g of 2-methyl-2-ethyl-3-hydroxyethyl-1,3-oxazolidine were mixed, degassed under vacuum, filled into packaging materials, and sealed to obtain polyurethane adhesive component B.
[0058] Comparative Example 3
[0059] 60.00 g of refined castor oil was degassed under vacuum, then filled into packaging materials and sealed to obtain polyurethane adhesive component A; at room temperature, 11.88 g of PM-200, 5.94 g of TDI and 0.0238 g of 2-methyl-2-ethyl-3-hydroxyethyl-1,3-oxazolidine were mixed, degassed under vacuum, filled into packaging materials and sealed to obtain polyurethane adhesive component B.
[0060] Example 2
[0061] This embodiment provides a method for preparing a modified castor oil polyurethane adhesive containing catalytic groups, as detailed below:
[0062] S1. 10.00 g (10.5 mmol) of refined castor oil (hydroxyl value of 36.86 mgKOH / 100g, iodine value of 80 g / 100g), 3.58 g (31.5 mmol) of cysteine hydrochloride, and 0.5147 g (2.52 mmol) of 1-hydroxycyclohexylphenyl ketone were added sequentially to a single-necked round-bottom flask, followed by the addition of 32.91 g of methanol. The mixture was stirred to obtain a reaction solution with a mass concentration of 30%.
[0063] S2. Under high-purity nitrogen atmosphere, stirring at room temperature and ultraviolet light irradiation, the reaction was carried out for 6 h to obtain the product solution;
[0064] S3. Add potassium hydroxide in 2.2 molar amounts of castor oil and continue stirring at room temperature for 1 h. After removing methanol from the product solution using a rotary evaporator, add chloroform in 10 times the volume of methanol. Wash three times with deionized water of equal volume to the chloroform, separate the layers, and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. Place it in a vacuum drying oven at 40℃ and dry to constant weight to obtain the modified castor oil product.
[0065] 30.00 g of modified castor oil and 30.00 g of refined castor oil were mixed, degassed under vacuum, and then filled into packaging materials and sealed to obtain polyurethane adhesive component A. At room temperature, 18.29 g of TDI trimer, 15.54 g of TDI and 0.001 g of toluenesulfonyl isocyanate were mixed, degassed under vacuum, filled into packaging materials and sealed to obtain polyurethane adhesive component B.
[0066] Example 3
[0067] This embodiment provides a method for preparing a modified castor oil polyurethane adhesive containing catalytic groups, as detailed below:
[0068] S1. 10.00 g (10.5 mmol) of refined castor oil (hydroxyl value 36.86 mgKOH / 100g, iodine value 80 g / 100g), 3.58 g (31.5 mmol) of cysteine hydrochloride, and 0.6927 g (1.89 mmol) of 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone were added sequentially to a single-necked round-bottom flask, followed by the addition of 26.51 g of methanol. The mixture was stirred to obtain a reaction solution with a mass concentration of 35%.
[0069] S2. Under high-purity nitrogen atmosphere, stirring at room temperature and ultraviolet light irradiation, the reaction was carried out for 12 h to obtain the product solution;
[0070] S3. Add potassium hydroxide in a molar ratio of 1 mole of castor oil and sodium methoxide in a molar ratio of 1.5 moles of castor oil, and continue stirring at room temperature for 1 h. After removing methanol from the product solution using a rotary evaporator, add chloroform in a volume 10 times that of methanol, and wash three times with deionized water in a volume equal to that of chloroform. Separate the layers and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. This product is then dried in a vacuum drying oven at 40℃ to constant weight to obtain the modified castor oil product.
[0071] 40.00 g of modified castor oil and 20.00 g of refined castor oil were mixed, degassed under vacuum, and then filled into packaging materials and sealed to obtain polyurethane adhesive component A. At room temperature, 25.03 g of MDI, 17.33 g of TDI and 0.006 g of 3-ethyl-2-methyl-2-(3-methylbutyl)-1,3-oxazolidine were mixed, degassed under vacuum, filled into packaging materials and sealed to obtain polyurethane adhesive component B.
[0072] Example 4
[0073] This embodiment provides a method for preparing a modified castor oil polyurethane adhesive containing catalytic groups, as detailed below:
[0074] S1. 10.00 g (10.5 mmol) of refined castor oil (hydroxyl value 36.86 mgKOH / 100g, iodine value 80 g / 100g), 3.58 g (31.5 mmol) of cysteine hydrochloride, 0.1557 g (0.95 mmol) of 2-hydroxy-2-methyl-1-phenyl-1-propanone, and 0.3975 g (0.95 mmol) of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide were sequentially added to a single-necked round-bottom flask, followed by the addition of 31.31 g of methanol. The mixture was stirred to obtain a reaction solution with a mass concentration of 28%.
[0075] S2. Under high-purity nitrogen atmosphere, stirring at room temperature and ultraviolet light irradiation, the reaction was carried out for 8 h to obtain the product solution;
[0076] S3. Add potassium hydroxide in 2.0 molar amounts of castor oil and continue stirring at room temperature for 1 h. After removing methanol from the product solution using a rotary evaporator, add chloroform in 10 times the volume of methanol. Wash three times with deionized water of equal volume to the chloroform, separate the layers, and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. Place it in a vacuum drying oven at 40℃ and dry to constant weight to obtain the modified castor oil product.
[0077] 50.00 g of modified castor oil was degassed under vacuum, then filled into packaging materials and sealed to obtain polyurethane adhesive component A; at room temperature, 20.96 g of MDI, 22.22 g of IPDI and 0.04 g of 3-butyl-2-(1-ethylpentyl)oxazolidine were mixed, degassed under vacuum, filled into packaging materials and sealed to obtain polyurethane adhesive component B.
[0078] Example 5
[0079] This embodiment provides a method for preparing a modified castor oil polyurethane adhesive containing catalytic groups, as detailed below:
[0080] S1. 10.00 g (10.5 mmol) of refined castor oil (hydroxyl value 36.86 mgKOH / 100g, iodine value 80 g / 100g), 3.58 g (31.5 mmol) of cysteine hydrochloride, and 0.5250 g (2.52 mmol) of α,α'-diethoxyacetophenone were added sequentially to a single-necked round-bottom flask, followed by the addition of 40.15 g of methanol. The mixture was stirred to obtain a reaction solution with a mass concentration of 26%.
[0081] S2. Under high-purity nitrogen atmosphere, stirring at room temperature and ultraviolet light irradiation, the reaction was carried out for 20 h to obtain the product solution;
[0082] S3. Add 0.8 molar amounts of sodium hydroxide and 1.0 molar amounts of sodium methoxide to the castor oil, and continue stirring at room temperature for 1 h. After removing methanol from the product solution using a rotary evaporator, add 10 times the volume of chloroform to the methanol solution, and wash three times with an equal volume of deionized water. Separate the layers and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. This product is then dried in a vacuum drying oven at 40℃ to constant weight to obtain the modified castor oil product.
[0083] 40.00 g of modified castor oil and 25.00 g of refined castor oil were mixed, degassed under vacuum, and then filled into packaging materials and sealed to obtain polyurethane adhesive component A. At room temperature, 19.83 g of HMDI, 25.82 g of PM-200 and 0.001 g of toluenesulfonyl isocyanate were mixed, degassed under vacuum, filled into packaging materials and sealed to obtain polyurethane adhesive component B.
[0084] Performance testing and comparative experiments
[0085] (1) Characterization of product structure
[0086] The modified castor oil and refined castor oil obtained in Example 1 were tested for infrared spectra using the potassium bromide tablet method. The test results are shown in [Figure 1]. Figure 1 .
[0087] As shown in the figure, the control sample refined castor oil was tested at a wavenumber of 1739 cm⁻¹. -1 A strong absorption peak was observed at 1739 cm⁻¹ (attributed to the CH₂=CH₂ absorption peak in the castor oil structure), indicating that the refined castor oil contained a large number of double bond functional groups before the modification reaction. The modified castor oil obtained in Example 1 showed a strong absorption peak at 1739 cm⁻¹. -1 The absorption peak at 1123 cm⁻¹ almost disappeared, indicating that the CH₂=CH₂ bond in refined castor oil underwent a thiol-olefin addition reaction with the cysteine salt. Meanwhile, at 1123 cm⁻¹... -1A strong absorption peak appeared at [value missing] (attributed to the characteristic absorption peak of -NH3Cl), indicating that the modified castor oil prepared in Example 1 contains a large number of -NH3Cl functional groups. Additionally, at a wavenumber of 3450 cm⁻¹... -1 A broader absorption peak, stronger than that of refined castor oil, appeared nearby, which was attributed to the absorption peaks of the -OH and -NH2 groups.
[0088] Figure 2 The absorption peak of the modified castor oil obtained in Comparative Example 2 is at 1739 cm⁻¹. -1 No absorption peak was observed at 1123 cm⁻¹, indicating that all CH₂=CH₂ bonds in the modified castor oil had reacted. Furthermore, at 1123 cm⁻¹... -1 The absence of a characteristic absorption peak for -NH3Cl at 3450 cm⁻¹ indicates that all -NH3Cl in the modified castor oil obtained in Example 2 underwent neutralization with the strong base (all -NH3Cl reacted to form -NH2). Correspondingly, at a wavenumber of 3450 cm⁻¹, the characteristic absorption peak for -NH3Cl was not observed. -1 It exhibits a stronger absorption peak than refined castor oil, which is attributed to the absorption peaks of -OH and -NH2 groups.
[0089] (2) Reaction performance
[0090] The polyurethane adhesives obtained in Example 1 and Comparative Example 1 were mixed at a weight ratio, and their reactivity was determined by Netzsch DSC. The test results are shown in the figure. Figure 3 See a in Table 1. The modified castor oil obtained in Example 1 was neutralized with sodium hydroxide and then cured with HDI trimer. The reaction process was monitored by DSC, and the test results are shown in [Table 1]. Figure 3 b. Test conditions: nitrogen atmosphere, aluminum crucible, test temperature range 30 ~ 180 ℃, heating rate 20 ℃ / min.
[0091] from Figure 3 As can be seen from a in the figure and Table 1, the initial reaction temperature (T) of the adhesive measured in Example 1 is... on ), exothermic peak temperature (T) peak ), termination reaction temperature (T) end The values of the values in Example 1 and Comparative Example 1 are both lower than those in Comparative Example 1, indicating that the polyurethane adhesive obtained in Example 1 has a faster reaction rate and a more concentrated exothermic reaction (approximately twice that of the adhesive prepared in Comparative Example 1). The adhesive obtained in Example 1 has both lower initial and final reaction temperatures, indicating that the two components react more rapidly. This demonstrates that the -NH3Cl functional group in the molecule lowers the activation energy and shortens the curing time. Furthermore, compared to Comparative Example 1, the enthalpy of reaction in Example 1 is higher for the same mass of adhesive, indicating that more reactive groups (-OH, -NH2) react with -NCO in the adhesive of Example 1. Figure 3As can be seen from b in Example 1, T on T peak and T end The results were all at the lowest values, proving that the -NH3Cl functional group has a catalytic effect on the reaction of polyurethane adhesives.
[0092] Table 1. DSC measurement results of Example 1 and Comparative Example 1
[0093]
[0094] (3) Adhesive performance
[0095] Components A and B of Example 1 and Comparative Example 1 were mixed in a specific ratio and applied to a steel sample with an overlap area of 12.5 ± 0.25 mm × 25 ± 0.20 mm. The bonded steel sample was clamped and fixed with dovetail clips and cured in a 60 ℃ forced-air oven for 4 hours to obtain a tensile-shear test specimen. The specimen was subjected to tensile testing on a universal testing machine at a tensile speed of 1 mm / min, and the stress-strain curve was obtained. Figure 4 ).from Figure 4 It can be seen that the specimen prepared with the polyurethane adhesive obtained in Example 1 has a tensile shear strength of 6.05 MPa and an elongation at break of 2.15%; while the specimen prepared with the adhesive in Comparative Example 1 has a tensile shear strength of 1.76 MPa and an elongation at break of 2.23%. This indicates that the specimen prepared with the adhesive obtained in Example 1 has higher tensile shear properties.
[0096] The components A and B of the remaining examples and comparative examples were mixed in proportion and cured in a 60 °C forced-air oven for 4 h to prepare specimens for tensile-shear tests. The measured tensile strength and elongation at break are summarized in Table 2. As can be seen from the data in Table 2, the adhesive strength of the specimens prepared in the tested examples is much higher than that of the specimens prepared in Comparative Examples 1 and 3.
[0097] Table 2. Adhesive properties of each embodiment and comparative example
[0098]
[0099] Where there is no conflict, the above embodiments and features described herein can be combined with each other.
[0100] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A modified castor oil polyurethane adhesive containing catalytic groups, characterized in that, It includes two components, A and B. By weight, component A includes 30.0-50.0 parts of modified castor oil and 0.0-30.0 parts of refined castor oil, and component B includes 30.0-50.0 parts of polyisocyanate or polyisocyanate modifier and 0.00-0.05 parts of dehydrating agent. The method for preparing the modified castor oil includes the following steps: S1. Add a mixture of refined castor oil and cysteine hydrochloride at a molar ratio of 1:3, and add 3-8% of photoinitiator and methanol of cysteine hydrochloride. Stir to obtain a reaction solution with a mass concentration of 25-40%. S2. Under high-purity nitrogen atmosphere, stirring, room temperature and ultraviolet light irradiation conditions, react for 6~24 h to obtain product solution; S3. Add a strong base less than 3 times the molar amount of castor oil and continue stirring at room temperature for a period of time. After removing methanol from the product solution using a rotary evaporator, add chloroform, wash with deionized water, separate the layers, and collect the lower organic phase. After removing chloroform from the organic phase using a rotary evaporator, a viscous product is obtained. Dry to constant weight to obtain the modified castor oil product. The strong base is at least one of sodium methoxide, sodium hydroxide, and potassium hydroxide.
2. The modified castor oil polyurethane adhesive containing catalytic groups as described in claim 1, characterized in that, The molecular structural formula of the modified castor oil is as follows: , where R= Or R= And R is The number is 1.
3. The modified castor oil polyurethane adhesive containing catalytic groups as described in claim 1, characterized in that, The structural formula of the polyisocyanate is as follows: , , , , , , , , or At least one of them.
4. The modified castor oil polyurethane adhesive containing catalytic groups as described in claim 1, characterized in that, The polyisocyanate modifier is at least one of TDI trimer, HDI trimer, IPDI trimer, polyphenyl polymethylene polyisocyanate, PM-200, NT-8075, S-325 or S-310.
5. The modified castor oil polyurethane adhesive containing catalytic groups as described in claim 1, characterized in that, The photoinitiator is at least one of the following: benzoin dimethyl ether, 2-hydroxy-2-methyl-1-phenyl-1-propanone, isopropylthioxanthone, benzophenone, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, α,α'-diethoxyacetophenone, ethyl 4-(N,N-dimethylamino)benzoate, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, methyl o-benzoylformate, methyl o-benzoylbenzoate, or ethyl 2,4,6-trimethylbenzoylphenylphosphine.
6. The modified castor oil polyurethane adhesive containing catalytic groups as described in claim 1, characterized in that, The dehydrating agent is at least one of p-toluenesulfonyl isocyanate, 3-ethyl-2-methyl-2-(3-methylbutyl)-1,3-oxazolidine, 3-butyl-2-(1-ethylpentyl)oxazolidine, and 2-methyl-2-ethyl-3-hydroxyethyl-1,3-oxazolidine.
7. A method for preparing a modified castor oil polyurethane adhesive containing a catalytic group as described in any one of claims 1-6, characterized in that, The preparation method involves preparing the following components by weight: Component A includes 30.0~50.0 parts of modified castor oil and 0.0~30.0 parts of refined castor oil; Component B includes 30.0~50.0 parts of polyisocyanate or polyisocyanate modifier and 0.00~0.05 parts of dehydrating agent. At room temperature, component A is mixed, degassed under vacuum, and then filled into packaging and sealed. Component B is mixed, degassed under vacuum at room temperature, filled into packaging, and sealed to obtain polyurethane adhesive.
8. The application of a modified castor oil polyurethane adhesive containing catalytic groups as described in any one of claims 1-6 in the packaging and formulation process of new energy batteries.