Preparation method and application of bio-based dihydric alcohol-based polyurethane dispersion

Abstract

The invention relates to the field of chemical synthesis technologies and new materials for coatings, and discloses a preparation method and application of a bio-based dihydric alcohol-based polyurethane dispersoid, and the preparation method of the bio-based dihydric alcohol-based polyurethane dispersoid comprises the following steps: under a protective atmosphere, adding a catalyst and a catalyst, the preparation method comprises the following steps: mixing poly (trimethylene carbonate) dihydric alcohol and an anionic hydrophilic chain extender for reaction at 100-120 DEG C, adding isocyanate into the mixture, and reacting at 80-85 DEG C under the action of a catalyst to obtain a prepolymer; and adding a mixed solution of a chain extender and a neutralizer into the prepolymer, and carrying out chain extension and emulsification to obtain the bio-based dihydric alcohol-based polyurethane dispersion. The bio-based dihydric alcohol-based polyurethane dispersoid can provide excellent adhesive force for butyl rubber, the problem that a butyl rubber coating film is difficult to adhere is effectively solved, fluoroether dihydric alcohol is further introduced, the polycarbonate-fluoroether copolymerized bio-based dihydric alcohol-based polyurethane dispersoid is synthesized, effective adhesion to the butyl rubber is achieved, and meanwhile, the adhesive force of the butyl rubber is greatly improved. And surface hydrophobic characteristics are provided.

Description

Technical Field

[0001] The invention belongs to the field of chemical synthesis technology and new materials for coatings, and specifically relates to a preparation method and application of a bio-based diol-based polyurethane dispersion. Background Art

[0002] Butyl rubber, especially halogenated butyl rubber, is mainly a copolymer product synthesized from isobutylene and a small amount of isoprene. It is prepared by vulcanization with the addition of different additives, including accelerators, colorants, and antioxidants. It has excellent water vapor barrier properties and chemical stability and is widely used in the field of medical packaging, including rubber stoppers, pen-type syringe pistons, protective caps, gaskets, etc. It is an important drug contact material. Therefore, the residual monomers and additives in butyl rubber, as well as the insoluble particles and small molecules that fall off during sterilization and storage, and the debris generated during the puncture process, all pose a risk of contaminating the drug solution. On the other hand, butyl rubber has high viscoelasticity and is very easy to adhere during the production process. Therefore, appropriate treatment of the butyl rubber surface is of great significance for preventing leakage and improving production and processing efficiency.

[0003] There are various methods for protecting the surface of butyl rubber, including film lamination technology, vacuum coating technology and surface silicone oil coating process. The main coating technologies include PTFE coating, Parylene coating, etc. These materials and coating processes are relatively expensive and complex; in addition, the use of silicone oil in the surface coating may bring the risk of silicone oil contaminating the drug. Although the coating method is simple in process, it is a commonly used surface protection and functionalization method. Butyl rubber is a vulcanized rubber, a type of dense cross-linked polymer with strong viscoelastic properties. The existing PTFE coating, Parylene coating and surface coating using silicone oil are difficult to adhere to the surface of butyl rubber, which in turn affects the protective effect on the butyl rubber surface. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a preparation method and application of a bio-based diol-based polyurethane dispersion.

[0005] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0006] Under a protective atmosphere, polytrimethylene carbonate diol and anionic hydrophilic chain extender are mixed at 100° C. to 120° C., and a viscosity modifier is added to obtain a mixture; wherein the mass ratio of polytrimethylene carbonate diol to anionic hydrophilic chain extender is 10 to 35:2 to 4;

[0007] Add isocyanate, viscosity modifier and catalyst to the mixture in sequence, react at 80°C to 85°C for 2h to 4h to obtain a prepolymer; wherein the mass ratio of polytrimethylene carbonate diol to isocyanate is 10-35:6-11; the mass ratio of isocyanate, viscosity modifier and catalyst is 6-11:0-15:0.015-0.035;

[0008] A mixed solution of adipic acid dihydrazide and N,N-dimethylethanolamine is added to the prepolymer, and the bio-based diol-based polyurethane dispersion is obtained after emulsification; wherein the mass ratio of the mixed solution to the prepolymer is 4-5:5-6; and the mass ratio of adipic acid dihydrazide and N,N-dimethylethanolamine in the mixed solution is 2-3:1.5-2.4. The preparation process of the bio-based diol-based polyurethane dispersion in the present invention is as follows: Figure 1 shown.

[0009] The molecular structure of the polytrimethylene carbonate diol in the present invention contains regular alkyl segments, which are compatible with butyl rubber segments, thereby achieving effective attachment of butyl rubber. This compatibility allows the coating film and butyl rubber to interpenetrate, fuse and attach to each other. In the preparation process, an anionic hydrophilic chain extender is added, which can be neutralized with amines to form salts during the preparation process and dispersed in water through electrostatic stabilization. Isocyanate is used as a cross-linking monomer, and in the presence of a catalyst, a chain extender and a neutralizer, a bio-based diol-based polyurethane dispersion is obtained after chain extension and emulsification.

[0010] Preferably, the polytrimethylene carbonate diol is polytrimethylene carbonate diol, polytrimethylene carbonate-polycaprolactone diol or polytrimethylene carbonate-polytetrahydrofuran diol; the number average molecular weight of the polytrimethylene carbonate is 1000 g / mol to 3000 g / mol, and the molecular weight distribution is 1.5 to 4.

[0011] The anionic hydrophilic chain extender is any one of 2,2-dimethylol propionic acid, dimethylol butyric acid, 2-aminoethane sulfonic acid, 2-(diethanolamino)ethane sulfonic acid, and sodium ethylenediamine ethane sulfonate.

[0012] Preferably, the isocyanate is one of isophorone diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate or any combination thereof.

[0013] Preferably, the viscosity regulator is N-methylpyrrolidone or 2-butanone; and the catalyst is dibutyltin laurate.

[0014] Preferably, the preparation of the mixture further includes the step of adding fluoroether diol, wherein the mass ratio of polytrimethylene carbonate diol, anionic hydrophilic chain extender and fluoroether diol is 18-10:1.92:2-10. In the process of preparing the polyurethane dispersion, the introduction of the fluorinated monomer, i.e., fluoroether diol, can endow the bio-based diol-based polyurethane dispersion coating obtained when the bio-based diol-based polyurethane dispersion is applied to the surface of butyl rubber with a hydrophobic function, thereby having better water resistance and hydrophobicity.

[0015] Preferably, when preparing the mixture, the mixing reaction time is 0.5h to 2h; when preparing the mixture, the stirring speed is 280r / min to 300r / min.

[0016] The second object of the present invention is to provide a bio-based diol-based polyurethane dispersion prepared by the preparation method.

[0017] The third object of the present invention is to provide the use of the bio-based diol-based polyurethane dispersion in improving the adhesion of butyl rubber.

[0018] The fourth object of the present invention is to provide the use of the bio-based diol-based polyurethane dispersion in the preparation of a hydrophobic film on the surface of butyl rubber.

[0019] The fifth object of the present invention is to provide a hydrophobic film on the surface of butyl rubber, wherein the bio-based diol-based polyurethane dispersion provided by the second object of the present method is applied to the surface of butyl rubber to obtain the hydrophobic film on the surface of butyl rubber.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The bio-based diol-based polyurethane dispersion prepared by the method for preparing the bio-based diol-based polyurethane dispersion of the present invention can have excellent adhesion to butyl rubber, which provides a basis for the preparation of butyl rubber coating, is environmentally friendly and can be obtained from bio-based sources. The adhesion of the bio-based diol-based polyurethane dispersion in the process of coating butyl rubber depends on the compatibility between the alkyl segments in the polytrimethylene carbonate diol and the butyl rubber segments. This compatibility allows the coating and butyl rubber to penetrate, fuse and adhere to each other. Butyl rubber itself contains a small amount of polar groups, which generate intermolecular forces with the polar groups in the bio-based diol-based polyurethane dispersion, promoting the adhesion of the bio-based diol-based polyurethane dispersion coating.

[0022] 2. The present invention can impart hydrophobic function to the polyurethane coating by introducing fluorinated monomers, namely fluoroether diols. The bio-based diol-based polyurethane dispersion prepared after adding fluoroether diols is a fluorinated bio-based diol-based polyurethane dispersion. The fluorinated bio-based diol-based polyurethane dispersion is a polymer material with special properties. By introducing fluorine elements into the polyurethane molecular chain, the material is endowed with unique physical and chemical properties. The fluorinated bio-based diol-based polyurethane dispersion inherits the excellent adhesion, scratch resistance and stretchability of polyurethane materials, and improves the water resistance and stronger hydrophobicity of the polyurethane dispersion after film formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The invention provides a synthesis process of a bio-based diol-based polyurethane dispersion, wherein (1) is a polytrimethylene carbonate diol, (2) is isophorone diisocyanate, (3) is 2,2-dihydroxymethyl propionic acid, (4) is isocyanate, (5) is N,N-dimethylethanolamine, (6) is adipic acid dihydrazide, and (7) is a polyurethane dispersion.

[0024] Figure 2 It is the ATR-IR chart of butyl rubber in the present invention.

[0025] Figure 3 This is the ATR-IR graph of the bio-based diol-based polyurethane dispersion prepared in Example 3, Example 4 and Example 5 of the present invention.

[0026] Figure 4 The bio-based diol-based polyurethane dispersion prepared in Examples 3, 4 and 5 of the present invention is 1 HNMR spectrum.

[0027] Figure 5 This is the ATR-IR graph of the bio-based diol-based polyurethane dispersion prepared in Example 6, Example 7 and Comparative Example 2 of the present invention.

[0028] Figure 6 The bio-based diol-based polyurethane dispersion prepared in Example 6, Example 7 and Comparative Example 2 of the present invention is 1 HNMR.

[0029] Figure 7 This is the ATR-IR graph of the bio-based diol-based polyurethane dispersion prepared in Example 8, Example 9 and Comparative Example 3 of the present invention.

[0030] Figure 8 The bio-based diol-based polyurethane dispersion prepared in Example 8, Example 9 and Comparative Example 3 of the present invention is 1 HNMR spectrum.

[0031] Fig. 9 It is the molecular structure diagram of the raw materials in this invention.

[0032] Among them, the abbreviation of polyurethane dispersion is PUD, the abbreviation of polytrimethylene carbonate diol is PTMC, the abbreviation of polycaprolactone diol is PCL, and the abbreviation of polytetramethylene glycol is PTMEG. DETAILED DESCRIPTION

[0033] The technical solutions in the present invention will be described clearly and completely below in conjunction with the specific implementation of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The methods described in the embodiments of the present invention are conventional methods unless otherwise specified. The materials, reagents, etc. used can be obtained from commercial sources unless otherwise specified.

[0035] There are various methods for butyl rubber surface protection, among which the coating method is simple in process and easy to obtain materials, and has gradually gained market favor in recent years. However, butyl rubber is a vulcanized rubber, a dense cross-linked polymer with strong viscoelasticity and difficult to adhere, which brings challenges to the preparation of coated butyl rubber. Among them, the ATR-IR image of a typical butyl rubber is as follows Figure 2 shown.

[0036] PUD is an excellent elastomeric material with high stability and weather resistance. Its chemical structure is adjustable and it is an important material that may be used to achieve rubber surface coating protection. By introducing functional groups such as fluorine and silicon into PUD, multiple functions such as hydrophobicity, hydrophilicity and lubrication can be achieved, which makes it show broad application prospects in the field of pharmaceutical packaging. The introduction of specific modifiers can improve the basic properties of PUD and give it specific functionality, such as improving hydrolysis resistance and surface performance. PUD has a wide range of applications, from traditional coatings and adhesives to emerging automotive interior adhesives and floor materials. These applications show that PUD not only provides excellent performance, but also meets the market demand for high-performance materials.

[0037] PTMC is a type of bio-based material that meets the current needs of carbon emissions and resource recycling. PTMC not only has excellent water resistance, but also contains regular alkyl segments in its molecular structure. It is the preferred material for butyl rubber to adhere through the principle of like dissolves like. Therefore, by introducing it into PUD, effective adhesion of butyl rubber can be achieved. In addition, the introduction of fluorinated monomers can give the polyurethane coating a hydrophobic function. Fluorinated PUD is a polymer material with special properties. By introducing fluorine elements into the polyurethane molecular chain, the material is given unique physical and chemical properties. Fluorinated PUD inherits the excellent adhesion, scratch resistance and stretchability of polyurethane materials, and improves the water resistance of the film, and its surface is more hydrophobic.

[0038] The PTMC used in the present invention is a type of bio-based diol and an important candidate for reducing carbon emissions. Based on PTMC and its derivatives, the present invention synthesizes and prepares a series of HMDI / HDI / IPDI-based polyurethane dispersions, which can provide excellent adhesion to butyl rubber and provide a basis for the preparation of film-coated butyl rubber.

[0039] Table 1 Specifications and manufacturers of various raw materials

[0040] raw material factory Dicyclohexylmethane diisocyanate, HMDI Wanhua Chemical Hexamethylene diisocyanate, HDI Wanhua Chemical Isophorone diisocyanate, IPDI Wanhua Chemical Polytrimethylene carbonate-polycaprolactone diol, TBC2000 Fengyuan Bio Polytrimethylene carbonate diol, TBE2000 Fengyuan Bio Polytrimethylene carbonate-polytetramethylene glycol, TPT2000 Fengyuan Bio 2,2-Dihydroxymethylpropionic acid, DMPA Titan Technology N,N-Dimethylethanolamine, DMEA Yangzi Petrochemical Dibutyltin laurate, DBTDL Titan Technology Adipic acid dihydrazide Titan Technology N-Methylpyrrolidone, NMP Titan Technology Fluorinated ether glycol, PFPE, E10-H SolvaySolexis Deionized water

[0041] Among them, the structures of TBC2000, TPT2000, TBE2000, IPDI and E10-H are as follows Fig. 9 shown.

[0042] The following is a preparation method and application of a bio-based diol-based polyurethane dispersion.

[0043] Example 1

[0044] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0045] S1. At 110°C and in an N2-protected environment, add 24g of polytrimethylene carbonate diol and 1.92g of 2,2-dimethylol propionic acid into a three-necked flask. Connect a bubbler, a nitrogen bag and a mechanical stirrer to the three-necked flask. Heat the three-necked flask in an oil bath, set the stirrer speed to 280r / min, and stir for 30min until the mixture is evenly stirred.

[0046] S2. Mix 4.20 g of dicyclohexylmethane diisocyanate and 2.70 g of hexamethylene diisocyanate, add dropwise into a three-necked flask within 30 min, pass N2 protection at the same time, control the temperature at 80 ° C, add 10 g of N-methylpyrrolidone to adjust the viscosity of the system, and add dropwise 0.03 g of dibutyltin laurate to catalyze the reaction. Under the stirring of a mechanical stirrer, react for 2 h to obtain a prepolymer.

[0047] S3. After the reaction temperature is cooled to 50°C, a mixture of 1.56g of adipic acid dihydrazide, 1.25g of N,N-dimethylethanolamine and 50g of deionized water is uniformly added to the prepolymer, and then 10g of deionized water is added for rinsing. The mixture is stirred evenly with an electric stirrer for 30 minutes until emulsified to form a stable emulsion. The mixture is cooled to 30°C to obtain the bio-based diol-based polyurethane dispersion.

[0048] Example 2

[0049] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0050] S1. At 110°C and in an N2-protected environment, add 22g of polytrimethylene carbonate-polycaprolactone diol and 1.92g of 2,2-dimethylol propionic acid into a three-necked flask. Connect a bubbler, a nitrogen bag and a mechanical stirrer to the three-necked flask. Heat the three-necked flask in an oil bath heating pot, set the stirrer speed to 280r / min, and stir for 30min until the mixture is evenly stirred.

[0051] S2. Mix 4.20 g of dicyclohexylmethane diisocyanate and 2.70 g of hexamethylene diisocyanate, add dropwise into a three-necked flask within 30 min, pass N2 protection at the same time, control the temperature at 80 ° C, add 10 g of N-methylpyrrolidone to adjust the viscosity of the system, and add dropwise 0.03 g of dibutyltin laurate to catalyze the reaction. Under the stirring of a mechanical stirrer, react for 2 h to obtain a prepolymer.

[0052] S3. After the reaction temperature is cooled to 50°C, a mixture of 2.4g adipic acid dihydrazide, 1.95g N,N-dimethylethanolamine and 50g deionized water is uniformly added to the prepolymer, and then 10g of deionized water is added for rinsing. The mixture is stirred evenly with an electric stirrer for 30 minutes until emulsified to form a stable emulsion. The mixture is cooled to 30°C to obtain the bio-based diol-based polyurethane dispersion.

[0053] Example 3

[0054] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0055] S1. At 110°C and in an N2-protected environment, add 24g of polytrimethylene carbonate diol and 2.00g of 2,2-dimethylol propionic acid into a three-necked flask. Connect a bubbler, a nitrogen bag and a mechanical stirrer to the three-necked flask. Heat the three-necked flask in an oil bath, set the stirrer speed to 280r / min, and stir for 30min until the mixture is evenly stirred.

[0056] S2. Add 7.21 g of isophorone diisocyanate dropwise into a three-necked flask within 30 min, while passing N2 protection, control the temperature at 80°C, add 10 g of 2-butanone to adjust the viscosity of the system, and add 0.03 g of dibutyltin laurate dropwise to catalyze the reaction. Under stirring with a mechanical stirrer, react for 2 h to obtain a prepolymer.

[0057] S3. After the reaction temperature is cooled to 50°C, a pre-prepared mixture of 1.56g of adipic acid dihydrazide, 1.25g of N,N-dimethylethanolamine and 50g of deionized water is uniformly added to the prepolymer, and then 10g of deionized water is added for rinsing. The mixture is stirred evenly with an electric stirrer for 30 minutes until emulsified to form a stable emulsion. The mixture is cooled to 30°C to obtain the bio-based diol-based polyurethane dispersion.

[0058] Example 4

[0059] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0060] S1. At 110°C and in an N2-protected environment, add 22g of polytrimethylene carbonate-polycaprolactone diol and 1.92g of 2,2-dimethylol propionic acid into a three-necked flask. Connect a bubbler, a nitrogen bag and a mechanical stirrer to the three-necked flask. Heat the three-necked flask in an oil bath heating pot, set the stirrer speed to 280r / min, and stir for 30min until the mixture is uniformly stirred.

[0061] S2. Add 7.21 g of isophorone diisocyanate dropwise into a three-necked flask within 30 min, while passing N2 protection, control the temperature at 80°C, add 10 g of 2-butanone to adjust the viscosity of the system, and add 0.02 g of dibutyltin laurate dropwise to catalyze the reaction. Under stirring with a mechanical stirrer, react for 2 h to obtain a prepolymer.

[0062] S3. After the reaction temperature is cooled to 50°C, a pre-prepared mixture of 1.56g of adipic acid dihydrazide, 1.25g of N,N-dimethylethanolamine and 50g of deionized water is uniformly added to the prepolymer, and then 10g of deionized water is added for rinsing. The mixture is stirred evenly with an electric stirrer for 30 minutes until emulsified to form a stable emulsion. The mixture is cooled to 30°C to obtain the bio-based diol-based polyurethane dispersion.

[0063] Example 5

[0064] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0065] S1. At 110°C and in an N2-protected environment, add 22g of polytrimethylene carbonate-polytetrahydrofuran diol and 1.92g of 2,2-dihydroxymethyl propionic acid into a three-necked flask. Connect a bubbler, a nitrogen bag and a mechanical stirrer to the three-necked flask. Heat the three-necked flask in an oil bath heating pot, set the stirrer speed to 280r / min, and stir for 30min until the mixture is evenly stirred.

[0066] S2. Add 7.21 g of isophorone diisocyanate dropwise into a three-necked flask within 30 min, while passing N2 protection, control the temperature at 80°C, add 10 g of N-methylpyrrolidone to adjust the viscosity of the system, and add 0.03 g of dibutyltin laurate dropwise to catalyze the reaction. Under stirring with a mechanical stirrer, react for 2 h to obtain a prepolymer.

[0067] S3. After the reaction temperature is cooled to 50°C, a pre-prepared mixture of 1.56g of adipic acid dihydrazide, 1.25g of N,N-dimethylethanolamine and 50g of deionized water is uniformly added to the prepolymer, and then 10g of deionized water is added for rinsing. The mixture is stirred evenly with an electric stirrer for 30 minutes until emulsified to form a stable emulsion. The mixture is cooled to 30°C to obtain the bio-based diol-based polyurethane dispersion.

[0068] Example 6

[0069] A method for preparing a bio-based diol-based polyurethane dispersion, wherein the polyurethane dispersion is a fluorinated polyurethane dispersion, specifically comprising the following steps:

[0070] S1. At 110°C and in an N2 protected environment, add 18g of polytrimethylene carbonate diol, 1.92g of 2,2-dihydroxymethylpropionic acid and 2g of fluoroether diol into a four-necked flask. Connect a bubbler, nitrogen and a mechanical stirrer to the four-necked flask. Heat with an oil bath heating pot. Set the stirrer speed to 300r / min and stir for 2h to remove moisture from the system.

[0071] S2. Cool down to 65°C, slowly add 7.21g of isophorone diisocyanate to the above solution with a constant pressure funnel within 10min, and pass N2 protection at the same time. Raise the temperature to 85°C, rinse the constant pressure funnel with 10.12g of 2-butanone. At the same time, butanone can also adjust the viscosity of the system. In order to catalyze the reaction, add 0.02g of dibutyltin dilaurate by dropwise addition, react for 4h, and obtain a prepolymer.

[0072] S3. After the reaction temperature is cooled to 50°C, a solution of 1.56g of adipic acid dihydrazide, 50g of deionized water and 1.25g of N,N-dimethylethanolamine is added dropwise to the prepolymer within 30 minutes, followed by adding 10g of deionized water for washing, and the mixture is fully mixed with an electric stirrer, and stirred for 30 minutes for emulsification treatment to form a stable emulsion, which is then cooled to 30°C to obtain the fluorinated bio-based diol-based polyurethane dispersion.

[0073] Example 7

[0074] A method for preparing a bio-based diol-based polyurethane dispersion, wherein the polyurethane dispersion is a fluorinated polyurethane dispersion, specifically comprising the following steps:

[0075] S1. Add 15g of polytrimethylene carbonate diol, 1.92g of 2,2-dimethylol propionic acid and 5g of fluoroether diol to a four-necked flask at 110°C and N2 protection. Connect a bubbler, nitrogen and a mechanical stirrer to the four-necked flask. Heat in an oil bath, set the stirrer speed to 300r / min, and stir for 2h to remove moisture from the system.

[0076] S2. Cool down to 65°C, slowly add 7.21g of isophorone diisocyanate to the above solution with a constant pressure funnel within 10min, and pass N2 protection at the same time. Raise the temperature to 85°C, rinse the constant pressure funnel with 10.12g of 2-butanone. At the same time, butanone can also adjust the viscosity of the system. In order to catalyze the reaction, add 0.02g of dibutyltin dilaurate by dropwise addition, react for 4h, and obtain a prepolymer.

[0077] S3. After the reaction temperature is cooled to 50°C, a solution containing 1.56g of adipic acid dihydrazide, 50g of deionized water and 1.25g of N,N-dimethylethanolamine prepared in advance is added dropwise to the prepolymer at a constant rate, followed by adding 10g of deionized water for washing, and the mixture is fully mixed with an electric stirrer, and emulsified for 30min to form a stable emulsion. After cooling to 30°C, the fluorinated bio-based diol-based polyurethane dispersion is obtained.

[0078] Example 8

[0079] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0080] S1. At 110°C and N2 protected environment, add 18g of polytrimethylene carbonate-polycaprolactone diol, 1.92g of 2,2-dimethylol propionic acid and 2g of fluoroether diol into a four-necked flask; connect a bubbler, nitrogen and a mechanical stirrer to the four-necked flask. Use an oil bath heating pot to heat, set the stirrer speed to 300r / min, and stir for 2h to remove moisture from the system.

[0081] S2. Cool down to 65°C, slowly add 7.21g of isophorone diisocyanate to the above solution with a constant pressure funnel within 10min, and pass N2 protection at the same time. Raise the temperature to 85°C, rinse the constant pressure funnel with 10.12g of 2-butanone. At the same time, butanone can also adjust the viscosity of the system. In order to catalyze the reaction, add 0.02g of dibutyltin dilaurate by dropwise addition, react for 4h, and obtain a prepolymer.

[0082] S3. After the reaction temperature is cooled to 50°C, a solution of 1.56g of adipic acid dihydrazide, 50g of deionized water and 1.25g of N,N-dimethylethanolamine is added dropwise to the prepolymer at a constant rate, followed by adding 10g of deionized water for washing, and the mixture is fully mixed with an electric stirrer, and stirred for 30 minutes for emulsification treatment to form a stable emulsion, which is then cooled to 30°C to obtain the fluorinated bio-based diol-based polyurethane dispersion.

[0083] Example 9

[0084] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0085] S1. Add 15g of polytrimethylene carbonate-polycaprolactone diol, 1.92g of 2,2-dimethylol propionic acid and 5g of fluoroether diol to a four-necked flask at 110°C and N2 protection. Connect a bubbler, nitrogen and a mechanical stirrer to the four-necked flask. Heat in an oil bath, set the stirrer speed to 300r / min, and stir for 2h to remove moisture from the system.

[0086] S2. Cool down to 65°C, slowly add 7.21g of isophorone diisocyanate to the above solution with a constant pressure funnel within 10min, and pass N2 protection at the same time. Raise the temperature to 85°C, rinse the constant pressure funnel with 10.12g of 2-butanone. At the same time, butanone can also adjust the viscosity of the system. In order to catalyze the reaction, add 0.02g of dibutyltin dilaurate by dropwise addition, react for 4h, and obtain a prepolymer.

[0087] S3. After the reaction temperature is cooled to 50°C, a solution containing 1.56g of adipic acid dihydrazide, 50g of deionized water and 1.25g of N,N-dimethylethanolamine prepared in advance is added dropwise to the prepolymer at a constant rate, followed by adding 10g of deionized water for washing, and the mixture is fully mixed with an electric stirrer, and stirred for 30 minutes for emulsification treatment to form a stable emulsion, which is cooled to 30°C to obtain the fluorinated bio-based diol-based polyurethane dispersion.

[0088] Comparative Example 1

[0089] A method for preparing a bio-based diol-based polyurethane dispersion comprises the following steps:

[0090] S1. At 110°C and in an N2-protected environment, add 31.95g of polytrimethylene carbonate-polytetrahydrofuran diol, 3.00g of 2,2-dimethylol propionic acid and 15.00g of N-methylpyrrolidone into a three-necked flask. Connect a bubbler, a nitrogen bag and a mechanical stirrer to the three-necked flask. Heat the three-necked flask in an oil bath heating pot, set the stirrer speed to 280r / min, and stir for 30min until the mixture is uniformly stirred.

[0091] S2. Mix 6.33 g of dicyclohexylmethane diisocyanate and 4.06 g of hexamethylene diisocyanate, and add dropwise into a three-necked flask within 30 min. Add isocyanate and diol in a molar ratio of 1:2. At the same time, pass N2 for protection. Control the temperature at 80 ° C. Add 15 g of N-methylpyrrolidone to adjust the viscosity of the system, and dropwise add 0.03 g of dibutyltin laurate to catalyze the reaction. Under stirring with a mechanical stirrer, react for 2 h to obtain a prepolymer.

[0092] S3. After the reaction temperature is cooled to 50°C, a pre-prepared mixed solution of 2.4g adipic acid dihydrazide and 1.95g N,N-dimethylethanolamine is uniformly added to the prepolymer, and then 90g of deionized water is added for rinsing. The mixture is stirred evenly with an electric stirrer for 30 minutes until emulsified to form a stable emulsion. The mixture is cooled to 30°C to obtain the bio-based diol-based polyurethane dispersion.

[0093] Comparative Example 2

[0094] A method for preparing a fluorinated bio-based diol-based polyurethane dispersion comprises the following steps:

[0095] S1. Add 18g of polytrimethylene carbonate diol, 1.92g of 2,2-dimethylol propionic acid and 10g of fluoroether diol into a four-necked flask at 110°C and N2 protection. Connect a bubbler, nitrogen and a mechanical stirrer to the four-necked flask. Heat in an oil bath, set the stirrer speed to 300r / min, and stir for 2h to remove moisture from the system.

[0096] S2. Cool down to 65°C, slowly add 7.21g of isophorone diisocyanate to the above solution with a constant pressure funnel within 10min, and pass N2 protection at the same time. Raise the temperature to 85°C, rinse the constant pressure funnel with 10.12g of 2-butanone. At the same time, butanone can also adjust the viscosity of the system. In order to catalyze the reaction, add 0.02g of dibutyltin dilaurate by dropwise addition, react for 4h, and obtain a prepolymer.

[0097] S3. After the reaction temperature is cooled to 50°C, a solution containing 1.56g of adipic acid dihydrazide, 50g of deionized water and 1.25g of N,N-dimethylethanolamine prepared in advance is added dropwise to the prepolymer within 30 minutes, followed by adding 10g of deionized water for washing, and the mixture is fully mixed with an electric stirrer, and emulsified by stirring for 30 minutes to form a stable emulsion. After cooling to 30°C, the fluorinated bio-based diol-based polyurethane dispersion is obtained.

[0098] Comparative Example 3

[0099] A method for preparing a fluorinated bio-based diol-based polyurethane dispersion comprises the following steps:

[0100] S1. At 110°C and N2 protected environment, add 18g of polytrimethylene carbonate-polycaprolactone diol, 1.92g of 2,2-dimethylol propionic acid and 10g of fluoroether diol into a four-necked flask. Connect a bubbler, nitrogen and a mechanical stirrer to the four-necked flask. Use an oil bath heating pot to heat, set the stirrer speed to 300r / min, and stir for 2h to remove moisture from the system.

[0101] S2. Cool down to 65°C, slowly add 7.21g of isophorone diisocyanate to the above solution with a constant pressure funnel within 10min, and pass N2 protection at the same time. Raise the temperature to 85°C, rinse the constant pressure funnel with 10.12g of 2-butanone. At the same time, butanone can also adjust the viscosity of the system. In order to catalyze the reaction, add 0.02g of dibutyltin dilaurate by dropwise addition, react for 4h, and obtain a prepolymer.

[0102] S3. After the reaction temperature is cooled to 50°C, a solution containing 1.56g of adipic acid dihydrazide, 50g of deionized water and 1.25g of N,N-dimethylethanolamine prepared in advance is added dropwise to the prepolymer within 30 minutes, followed by adding 10g of deionized water for washing, and the mixture is fully mixed with an electric stirrer, and emulsified by stirring for 30 minutes to form a stable emulsion. After cooling to 30°C, the fluorinated bio-based diol-based polyurethane dispersion is obtained.

[0103] 1. Structural characterization

[0104] ATR-IR and 1 HNMR, such as Figure 3 and Figure 4 As shown. Figure 3 It can be seen that these three PUDs all have NH at 3320cm -1 The stretching vibration of C=O at 1724cm -1 The stretching vibration at 1580 cm-1 The stretching vibration at 2935 cm-1 indicates that all three PUDs were successfully synthesized. -1 and symmetrical stretching vibration peak 2863cm -1 The alkyl chain structures in the three PUDs were confirmed, and the 1105 cm -1 The COC absorption peak from Figure 4 It can be seen that 2.03-2.09 ppm is COOCH2CH2CH2O, 4.22-4.27 ppm is COOCH2CH2CH2O, which confirms the existence of PTMC structure in PTMC-PUD, PTMC-PCL-PUD and PTMC-PTMEG-PUD, 2.30-2.35 ppm is COCH2CH2CH2CH2CH2CH2O, which can confirm the structure of PCL in PTMC-PCL-PUD, and 3.41-3.45 ppm is OCH2CH2CH2CH2O, which indicates the existence of PTMEG structure in PTMC-PTMEG-PUD.

[0105] Figure 5 The ATR-IR graphs of the bio-based diol-based polyurethane dispersions prepared in Example 6, Example 7 and Comparative Example 2 are shown in Table 1. Figure 5 It can be seen that the N–H (3320 cm-1) -1 )、C=O(1724cm -1 ) and C–N (1580cm -1 ), indicating that all three PUDs were successfully synthesized; and there is a stretching vibration at 1235cm -1 and 775cm -1 The CF stretching vibration peak at , and the intensity becomes stronger as the amount of E10-H introduced increases.

[0106] Figure 6 The bio-based diol-based polyurethane dispersion prepared in Example 6, Example 7 and Comparative Example 2 1 HNMR. Combination Figure 5 , 2.03-2.09 ppm (COOCH2CH2CH2O), 4.22-4.27 (COOCH2CH2CH2O) ppm indicate that these three PUDs are PUDs synthesized based on PTMC-OH and E10-H.

[0107] Figure 7 The ATR-IR graphs of the bio-based diol-based polyurethane dispersions prepared in Example 8, Example 9 and Comparative Example 3 are shown in Table 1. Figure 5Similarly, the PTMC-PCL-based PUDs obtained by copolymerization with different proportions of E10 have a 3320 cm -1 N–H, 1724 cm -1 C=O and 1580cm -1 The characteristic peak of C–N stretching vibration indicates that all three PUDs were successfully synthesized; -1 and 775cm -1 The CF stretching vibration peak at has a stronger vibration intensity as the E10 content increases.

[0108] Figure 8 The bio-based diol-based polyurethane dispersion prepared in Example 8, Example 9 and Comparative Example 3 1 HNMR. Combination Figure 7 , 2.30-2.35ppm(COCH2CH2CH2CH2CH2CH2O), 2.03-2.09ppm(COOCH2CH2CH2O), 4.22-4.27ppm(COOCH2CH2CH2O) can confirm that these three PUDs are PUDs synthesized based on PTMC-PCL-OH and E10-H.

[0109] 2. Performance Testing

[0110] The bio-based diol-based polyurethane dispersions prepared in Examples 1 to 9 and Comparative Examples 1 to 3 were sprayed onto the surface of butyl rubber and dried at 100° C. for 30 min to obtain a coated butyl rubber with a thickness of 30 μm to 50 μm. The method used to test adhesion is GB / T 9286-2021 "Scratch test for paints and varnishes".

[0111] Table 2 Adhesion of bio-based diol-based polyurethane dispersions prepared in different examples and comparative examples on butyl rubber

[0112]

[0113]

[0114]

[0115] Note: 2% fluoroether diol means the mass percentage of fluoroether diol in polyurethane dispersion; 5% fluoroether diol means the mass percentage of fluoroether diol in polyurethane dispersion; 10% fluoroether diol means the mass percentage of fluoroether diol in polyurethane dispersion.

[0116] As shown in Table 2, when hexamethylene diisocyanate and dicyclohexylmethane diisocyanate are used, the PUDs based on polytrimethylene carbonate diol and polytrimethylene carbonate-polycaprolactone copolymer diol have better adhesion to brominated and chlorinated butyl rubber than those based on polytrimethylene carbonate-polytetrahydrofuran copolymer diol. When isophorone diisocyanate is used, the PUDs based on polytrimethylene carbonate diol, polytrimethylene carbonate-polycaprolactone copolymer diol and polytrimethylene carbonate-polytetrahydrofuran copolymer diol can achieve excellent adhesion on the surface of brominated and chlorinated butyl rubber. This is because the surface composition of butyl rubber includes alkyl segments, polar vulcanized cross-linking structures, and chlorine or bromine elements. The three diols all have alkyl segments and polar carbonyl groups, which are conducive to the fusion and attachment of brominated and chlorinated butyl rubbers. Compared with hexamethylene diisocyanate, dicyclohexylmethane diisocyanate and isophorone diisocyanate, the longer isocyanate segments will reduce the alkyl fusion ability of the resulting PUD, and the carbon content of polytrimethylene carbonate-polytetrahydrofuran copolymer diol is lower than that of polytrimethylene carbonate diol and polytrimethylene carbonate-polycaprolactone copolymer diol, which reduces its adhesion to brominated and chlorinated butyl rubbers. In general, this provides a direction for the adhesion mechanism of butyl rubber substrates with high cross-linking density and high elasticity through coating processes without surface treatment, and provides a material basis. In addition, when the amount of fluoroether monomer introduced into the polytrimethylene carbonate diol, polytrimethylene carbonate-polycaprolactone copolymer diol and isophorone diisocyanate system reaches 10%, its adhesion to brominated and chlorinated butyl rubber is reduced, which also supports this adhesion process.

[0117] Table 3 Contact angles of TBE-PUD with different degrees of fluorination

[0118]

[0119]

[0120] Note: 2% fluoroether diol means the mass percentage of fluoroether diol in polyurethane dispersion; 5% fluoroether diol means the mass percentage of fluoroether diol in polyurethane dispersion; 10% fluoroether diol means the mass percentage of fluoroether diol in polyurethane dispersion.

[0121] As shown in Table 3, further introduction of fluoroether diol can effectively improve the hydrophobicity of the coating. At the same time, when the fluoroether modification equivalent reaches 5%, Example 7 and Example 9 can achieve contact angles of 92.861° and 95.514° respectively while ensuring adhesion. The successful introduction of fluorinated monomers has realized the preparation of bio-based diol-fluorinated polyether-based PUD. By changing the amount of fluorinated monomers, both the adhesion to butyl rubber and the provision of a hydrophobic surface can be taken into account, which provides a basis for the construction of functional coatings on the surface of butyl rubber.

[0122] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0123] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing a bio-based diol-based polyurethane dispersion, characterized in that: The following steps are involved: Under a protective atmosphere, removing water from polytrimethylene carbonate diol and anionic hydrophilic chain extender at 100° C. to 120° C. to obtain a mixture; wherein the mass ratio of polytrimethylene carbonate diol to anionic hydrophilic chain extender is 10-35:2-4; Add isocyanate, viscosity modifier and catalyst to the mixture in sequence, react at 80°C to 85°C for 2h to 4h to obtain a prepolymer; wherein the mass ratio of polytrimethylene carbonate diol to isocyanate is 10-35:6-11; the mass ratio of isocyanate, viscosity modifier and catalyst is 6-11:0-15:0.015-0.035; A mixed liquid of adipic acid dihydrazide and N,N-dimethylethanolamine is added to the prepolymer, and the bio-based diol-based polyurethane dispersion is obtained after emulsification; the mass ratio of the mixed liquid to the prepolymer is 4-5:5-6; the mass ratio of adipic acid dihydrazide and N,N-dimethylethanolamine is 2-3:1.5-2.

4.

2. The method for preparing a bio-based diol-based polyurethane dispersion according to claim 1, characterized in that: The polytrimethylene carbonate diol is polytrimethylene carbonate diol, polytrimethylene carbonate-polycaprolactone diol or polytrimethylene carbonate-polytetrahydrofuran diol; The anionic hydrophilic chain extender is any one of 2,2-dimethylol propionic acid, dimethylol butyric acid, 2-aminoethane sulfonic acid, 2-(diethanolamino)ethane sulfonic acid, and sodium ethylenediamine ethane sulfonate.

3. The method for preparing a bio-based diol-based polyurethane dispersion according to claim 1, characterized in that: The isocyanate is one of isophorone diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate or any combination thereof.

4. The method for preparing a bio-based diol-based polyurethane dispersion according to claim 1, characterized in that: The viscosity regulator is N-methylpyrrolidone or 2-butanone; the catalyst is dibutyltin laurate.

5. The method for preparing a bio-based diol-based polyurethane dispersion according to claim 1, characterized in that: The preparation of the mixture also includes the step of adding fluoroether diol; the mass ratio of polytrimethylene carbonate diol, anionic hydrophilic chain extender and fluoroether diol is 18-10:1.92:2-10.

6. The method for preparing a bio-based diol-based polyurethane dispersion according to claim 1, characterized in that: When preparing the mixture, the mixing reaction time is 0.5h to 2h.

7. The bio-based diol-based polyurethane dispersion prepared according to the preparation method according to any one of claims 1 to 6.

8. Use of the bio-based diol-based polyurethane dispersion according to claim 7 in improving the adhesion of butyl rubber.

9. Use of the bio-based diol-based polyurethane dispersion according to claim 7 in preparing a hydrophobic film on the surface of butyl rubber.

10. A butyl rubber surface hydrophobic film, characterized in that: The bio-based diol-based polyurethane dispersion according to claim 7 is applied to the surface of butyl rubber to obtain a hydrophobic film on the surface of the butyl rubber.

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