Synthetic method of environment-friendly waterborne polyurethane
By forming stable Sn-N bonds with organotin on the mesoporous silica SBA-15 support, the problem of organotin residue in polyurethane synthesis was solved, and the high efficiency of environmentally friendly waterborne polyurethane synthesis and catalytic efficiency were achieved.
Patent Information
- Application Number
- CN202510823070.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-19
- Publication Date
- 2025-12-12
Smart Images
Figure CN121108439A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of polyurethane catalytic synthesis, and particularly relates to a synthesis method of an environmentally-friendly waterborne polyurethane without organic tin residues. BACKGROUND
[0002] Polyurethane is a multi-block polymer composed of hard segments and soft segments, and the micro-phase separation structure caused by the thermodynamic incompatibility of the hard segments and the soft segments endows the polyurethane with excellent mechanical properties. As an ideal biomaterial, the polyurethane has been widely studied in the biomedical fields such as tissue engineering scaffolds, implants, hydrogels and drug carriers due to its flexible chemical structure design, different functions, good biocompatibility and easy preparation. Organic tin is one of the most commonly used organic metal catalysts, and is mainly used for the gelation reaction of polyurethane. In the reaction of isocyanate and polyol, the organic tin shows high selectivity. Common organic tin catalysts include dibutyltin dilaurate and stannous octoate, both of which have strong catalytic activity and can play the role of Lewis acid, promote the electrophilic activity of the isocyanate carbon atom after interacting with the isocyanate group, and accelerate the polymerization reaction rate.
[0003] With the wide application of organic tin compounds, people have begun to pay more attention to the toxicity effect research. Many countries have limited the use of organic tin. Although organic tin can be degraded through various pathways and gradually converted into low-toxicity inorganic tin, its accumulation in the environment and in the body still causes potential harm to the organism, including neurotoxicity, immunotoxicity and reproductive toxicity.
[0004] Therefore, we should pay attention to the problem of organic tin residues in the synthesis of polyurethane. Therefore, it is necessary to propose an environmentally-friendly polyurethane synthesis method without organic tin residues. SUMMARY
[0005] The present application aims at the deficiencies of the prior art, and proposes a preparation method of a carrier catalyst of organic tin and porous material composite, and a method for preparing environmentally-friendly waterborne polyurethane by using the carrier catalyst. The catalyst can avoid the interaction between the organic tin catalyst and the hydroxyl silicone oil to cause dissolution by inert modification of the carrier surface and catalyst stabilization technology, so as to greatly reduce the organic tin residues in the polyurethane synthesis process.
[0006] Technical scheme: The environmentally-friendly waterborne polyurethane synthesis method provided by the present application comprises the following steps:
[0007] (1) Pretreatment and hydrophobic modification of the support catalyst: Mesoporous silica SBA-15 was calcined at 550-650℃ for 1-2h to remove surface hydroxyl groups; long-chain alkyl silane was added and refluxed at 100-120℃ for 3-4h to obtain hydrophobic mesoporous silica SBA-15.
[0008] (2) Amination and DBTDL support: Hydrophobic mesoporous silica SBA-15 was mixed with aminosilane and reacted at 80-100℃ for 2-3 h to introduce -NH2 groups. DBTDL was then reacted with DBTDL in limonene at 60℃ for 4-5 h to fix the catalyst via Sn-N bonds, yielding an organotin supported catalyst.
[0009] (3) The synthesis of environmentally friendly waterborne polyurethane includes the following steps:
[0010] S1) Mix 120-150 parts of diisocyanate and a supported catalyst containing 0.001-0.005 parts of organotin evenly, add 200-400 parts of polyol, react at 40-50℃, determine the -NCO value in the reaction system using the di-n-butylamine method, and determine that the theoretical residual amount of isocyanate in the reaction system is ≤35%.
[0011] S2) Add 10-15 parts of hydrophilic chain extender and react at 40-50℃ for 1-3 hours;
[0012] S3) Add 25-30 parts of butanone oxime for polyurethane end-capping, and react at 70-80℃ for 1-2 hours;
[0013] S4) Cool to 35°C, add salting agent, react for 0.5-1 h, and slowly add deionized water under vigorous stirring to obtain environmentally friendly waterborne polyurethane;
[0014] After the reaction (S5) is complete, the mixture is filtered through a nylon membrane to recover the organotin-supported catalyst, which is then reused to catalyze the synthesis of waterborne polyurethane.
[0015] Furthermore, as a preferred embodiment, the long-chain alkylsilane is any one or more of octyltriethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, octadecyltrimethoxysilane, and octadecyltriethoxysilane.
[0016] Furthermore, as a preferred embodiment, the mercaptosilane is any one or more of 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and mercaptopropylmethyldimethoxysilane.
[0017] Furthermore, as a preferred embodiment, the organotin is any one or more of stannous octoate, dibutyltin dilaurate, and di(dodecyl sulfide)dibutyltin.
[0018] Furthermore, as a preferred embodiment, the polyol is any one or more of polyester polyol, polyether polyol, and hydroxyl silicone oil.
[0019] Further, as a preferred embodiment, the diisocyanate is any one or more of limonene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.
[0020] Further, as a preferred embodiment, the hydrophilic chain extender is any one or a mixture of 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, and N-methyldiethanolamine.
[0021] Furthermore, as a preferred embodiment, the salt-forming agent is any one or more mixtures of triethylamine, triethanolamine, ammonia, and acetic acid.
[0022] Beneficial effects: The mesoporous silica used in this invention has a high specific surface area and abundant mesoporous structure, which can fully contact the catalyst prepared with organotin support, improve the catalytic effect, and at the same time avoid the problem of tin residue caused by the homogeneous organotin catalysis of traditional polyurethane.
[0023] Long-chain alkylsilanes were used to modify the porous material SBA-15, forming a hydrophobic layer that blocked the contact between the -OH groups of the polyol and the tin centers. The modified support surface lacked free hydroxyl groups, thus avoiding competition for coordination with organotin compounds and preventing interference with polyurethane synthesis.
[0024] Using bidentate ligand bridging: first, an aminosilane is used to introduce -NH2 groups on the surface of the support, and then Sn-N covalent bonds are formed with organotin, which are more stable than Sn-O bonds and resistant to polyol interference. Attached Figure Description
[0025] Figure 1 The infrared spectrum of the unmodified porous material SBA-15 in Example 1;
[0026] Figure 2 The infrared spectrum of the supported catalyst obtained in Example 1; Figure 3 Pilot-scale process flow chart; Figure 4 Pilot production and factory production flow chart. Detailed Implementation
[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0028] Unless otherwise specified, all reagents and raw materials used in the embodiments and comparative examples of this invention were purchased from the market.
[0029] Example 1:
[0030] (1) Pretreatment and hydrophobic modification of the support catalyst: Mesoporous silica (SBA-15) was calcined at 550℃ for 2h to remove surface hydroxyl groups. Octadecyltrimethoxysilane was added and refluxed at 100℃ for 3h to obtain hydrophobic SBA-15;
[0031] (2) Amination and organotin support: Hydrophobic SBA-15 was mixed with 3-aminopropyltriethoxysilane and reacted at 100°C for 2 h to introduce -NH2 groups. It was then reacted with organotin in limonene at 60°C for 4 h to fix the catalyst through Sn-N bonds, thus obtaining a supported catalyst containing organotin.
[0032] (3) Synthesis of waterborne polyurethane:
[0033] S1) 144 parts of isophorone diisocyanate and a supported catalyst containing 0.001 parts of dibutyltin dilaurate were mixed evenly, 200 parts of hydroxyl silicone oil were added, and the reaction was carried out at 50°C. The -NCO value in the reaction system was determined by the di-n-butylamine method. The -NCO value of the reaction system reached the theoretical value (theoretical residual amount of isocyanate ≤35%).
[0034] S2) Add 10 parts of hydrophilic chain extender and react at 50°C for 2 hours;
[0035] S3) Add 25 parts of butanone oxime for polyurethane end-capping and react at 80°C for 1 hour;
[0036] S4) Cool to 35°C, add salting agent, react for 0.5 h, and slowly add deionized water under vigorous stirring to obtain waterborne polyurethane;
[0037] After the reaction (S5) is complete, the mixture is filtered through a nylon membrane to recover the organotin-supported catalyst, which is then reused to catalyze the synthesis of waterborne polyurethane.
[0038] The hydrophilic chain extender is N-methyldiethanolamine, and the salt-forming agent is acetic acid.
[0039] like Figure 1 The image shown is the infrared spectrum of the unmodified porous material SBA-15 in this embodiment. Figure 2The infrared spectrum of the supported catalyst obtained in Example 1 is shown. Figure 2 and Figure 1 In comparison, 1566.16cm -1 and 2927.11cm -1 The absorption peak at 1092.62 cm⁻¹ indicates successful amino modification. -1 The absorption peak of Sn-N is shown. Due to the influence of Sn-N, the absorption peak of Si-O-Si is shifted, proving that the supported catalyst was successfully obtained in this embodiment.
[0040] Example 2:
[0041] (1) Pretreatment and hydrophobic modification of the support catalyst: Mesoporous silica (SBA-15) was calcined at 550℃ for 1 h to remove surface hydroxyl groups. Octadecyltrimethoxysilane was added and refluxed at 100-120℃ for 3 h to obtain hydrophobic SBA-15;
[0042] (2) Amination and organotin support: Hydrophobic SBA-15 was mixed with 3-aminopropyltrimethoxysilane and reacted at 80°C for 2 h to introduce -NH2 groups. It was then reacted with organotin in limonene at 60°C for 4 h to fix the catalyst through Sn-N bonds, thus obtaining a supported catalyst containing organotin.
[0043] (3) The synthesis of waterborne polyurethane is the same as the steps in Example 1.
[0044] Example 3:
[0045] (1) Pretreatment and hydrophobic modification of the support catalyst: Mesoporous silica (SBA-15) was calcined at 550℃ for 1 h to remove surface hydroxyl groups. Octadecyltrimethoxysilane was added and refluxed at 120℃ for 3 h to obtain hydrophobic SBA-15;
[0046] (2) Amination and organotin support: Hydrophobic SBA-15 was mixed with N-aminoethyl-3-aminopropyltrimethoxysilane and reacted at 80°C for 2 h to introduce -NH2 groups. The mixture was then reacted with organotin in limonene at 60°C for 4 h to fix the catalyst via Sn-N bonds, thus obtaining a supported catalyst containing organotin.
[0047] (3) The synthesis of waterborne polyurethane is the same as the steps in Example 1.
[0048] Example 4:
[0049] (1) Pretreatment and hydrophobic modification of the support catalyst: Mesoporous silica (SBA-15) was calcined at 550℃ for 1 h to remove surface hydroxyl groups. Octadecyltrimethoxysilane was added and refluxed at 120℃ for 3 h to obtain hydrophobic SBA-15;
[0050] (2) Amination and organotin support: Hydrophobic SBA-15 was mixed with N-aminoethyl-3-aminopropyltrimethoxysilane and reacted at 90°C for 2 h to introduce -NH2 groups. The mixture was then reacted with organotin in limonene at 60°C for 4 h to fix the catalyst via Sn-N bonds, thus obtaining a supported catalyst containing organotin.
[0051] (3) The synthesis of waterborne polyurethane is the same as the steps in Example 1.
[0052] Comparative Example 1
[0053] The preparation method of waterborne polyurethane is the same as in the examples, but the organotin catalyst is added directly.
[0054] The preparation method is as follows:
[0055] Synthesis of waterborne polyurethane:
[0056] S1) Mix 120-150 parts of diisocyanate and 0.001 parts of dibutyltin dilaurate evenly, add 200-400 parts of hydroxyl silicone oil, react at 40-50℃, and determine the -NCO value in the reaction system using the di-n-butylamine method. The -NCO value of the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤35%).
[0057] S2) Add 10-15 parts of hydrophilic chain extender and react at 40-50℃ for 1-3 hours;
[0058] S3) Add 25-30 parts of butanone oxime for polyurethane end-capping, and react at 70-80℃ for 1-2 hours;
[0059] S4) Cool to 35°C, add salting agent, react for 0.5-1 h, and slowly add deionized water under vigorous stirring to obtain waterborne polyurethane;
[0060] Comparative Example 2
[0061] Organotin was directly loaded with mesoporous silica and used to prepare waterborne polyurethane.
[0062] The preparation method is as follows:
[0063] (1) SBA-15 organotin support: SBA-15 and organotin are reacted in limonene at 60°C for 4-5 h to obtain a supported catalyst containing organotin.
[0064] (2) Synthesis of waterborne polyurethane:
[0065] S1) Mix 120-150 parts of isophorone diisocyanate and a supported catalyst containing 0.001-0.005 parts of dibutyltin dilaurate evenly, add 200-400 parts of hydroxyl silicone oil, react at 40-50℃, and determine the -NCO value in the reaction system using the di-n-butylamine method. The -NCO value of the reaction system reaches the theoretical value (theoretical residual amount of isocyanate ≤35%).
[0066] S2) Add 10-15 parts of hydrophilic chain extender and react at 40-50℃ for 1-3 hours;
[0067] S3) Add 25-30 parts of butanone oxime for polyurethane end-capping, and react at 70-80℃ for 1-2 hours;
[0068] S4) Cool to 35°C, add salting agent, react for 0.5-1 h, and slowly add deionized water under vigorous stirring to obtain waterborne polyurethane;
[0069] After the S5 reaction is complete, the mixture is filtered through a nylon membrane to recover SBA-15, which is then used again to catalyze the synthesis of waterborne polyurethane.
[0070] The hydrophilic chain extender is N-methyldiethanolamine, and the salt-forming agent is acetic acid.
[0071] Performance testing
[0072] 1. The residual organotin content in the supported catalyst and the aqueous polyurethane after recovering the organotin supported catalyst was determined. The determination method is as follows:
[0073] (1) Sample preparation: Add 50 mg of sample to 10 mL of limonene and extract by ultrasonication for 30 min. Centrifuge and filter the supernatant through a 0.22 μm filter membrane. Repeat the extraction 3 times, combine the extracts, and concentrate to 1 mL by nitrogen blowing for analysis.
[0074] (2) Detection method: Inductively coupled plasma mass spectrometry (ICP-MS) was used for determination, and the calculation formula is as follows:
[0075]
[0076] Where: C: Tin concentration measured by ICP-MS (μg / L); V: Sample volume (mL); m: Sample mass (g).
[0077] 2. The initial catalytic efficiency and the catalytic efficiency after 20 cycles of recovery catalysis of the organotin supported catalyst were measured. The results of organotin content, tin residue, and catalyst catalytic efficiency are shown in Table 1.
[0078]
[0079] As can be seen from the results in the table, the waterborne polyurethane prepared by the present invention uses the recyclable organotin supported catalyst prepared by the present invention as a catalyst, the polyurethane conversion rate is high, and there is no organotin residue that is harmful to the environment and organisms.
[0080] 3. Process Flow
[0081] (1) Pilot-scale process flow
[0082] like Figure 3 As shown;
[0083] (2) Pilot-scale and factory production process
[0084] like Figure 4 As shown.
[0085] The above description is merely an embodiment of the present invention and does not limit the scope of patent protection. Any non-substantial changes or substitutions made by those skilled in the art based on the present invention will still fall within the scope of patent protection.
Claims
1. A method for synthesizing an environmentally friendly waterborne polyurethane, characterized in that... Includes the following steps: (1) Pretreatment and hydrophobic modification of the support catalyst: Mesoporous silica SBA-15 was calcined at 550-650℃ for 1-2h to remove surface hydroxyl groups; long-chain alkyl silane was added and refluxed at 100-120℃ for 3-4h to obtain hydrophobic mesoporous silica SBA-15. (2) Amination and DBTDL support: Hydrophobic mesoporous silica SBA-15 was mixed with aminosilane and reacted at 80-100℃ for 2-3 h to introduce -NH2 groups. DBTDL was then reacted with DBTDL in limonene at 60℃ for 4-5 h to fix the catalyst via Sn-N bonds, yielding an organotin supported catalyst. (3) The synthesis of environmentally friendly waterborne polyurethane includes the following steps: S1) Mix 120-150 parts of diisocyanate and a supported catalyst containing 0.001-0.005 parts of organotin evenly, add 200-400 parts of polyol, react at 40-50℃, determine the -NCO value in the reaction system using the di-n-butylamine method, and determine that the theoretical residual amount of isocyanate in the reaction system is ≤35%. S2) Add 10-15 parts of hydrophilic chain extender and react at 40-50℃ for 1-3 hours; S3) Add 25-30 parts of butanone oxime for polyurethane end-capping, and react at 70-80℃ for 1-2 hours; S4) Cool to 35°C, add salting agent, react for 0.5-1 h, and slowly add deionized water under vigorous stirring to obtain environmentally friendly waterborne polyurethane; After the reaction (S5) is complete, the mixture is filtered through a nylon membrane to recover the organotin-supported catalyst, which is then reused to catalyze the synthesis of waterborne polyurethane.
2. The method for synthesizing the environmentally friendly waterborne polyurethane according to claim 1, characterized in that: The long-chain alkylsilane is any one or more of octyltriethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, octadecyltrimethoxysilane, and octadecyltriethoxysilane.
3. The method for synthesizing the environmentally friendly waterborne polyurethane according to claim 1, characterized in that: The mercaptosilane is any one or more of 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and mercaptopropylmethyldimethoxysilane.
4. The method for synthesizing the environmentally friendly waterborne polyurethane according to claim 1, characterized in that: The organotin is any one or more of stannous octoate, dibutyltin dilaurate, and di(dodecyl sulfide)dibutyltin.
5. The method for synthesizing the environmentally friendly waterborne polyurethane according to claim 1, characterized in that: The polyol is any one or more of polyester polyol, polyether polyol, and hydroxyl silicone oil.
6. The method for synthesizing the environmentally friendly waterborne polyurethane according to claim 1, characterized in that: The diisocyanate is any one or more of limonene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.
7. The method for synthesizing the environmentally friendly waterborne polyurethane according to claim 1, characterized in that: The hydrophilic chain extender is any one or a mixture of 2,2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, and N-methyldiethanolamine.
8. The method for synthesizing the environmentally friendly waterborne polyurethane according to claim 1, characterized in that: The salt-forming agent is any one or a mixture of triethylamine, triethanolamine, ammonia, and acetic acid.