A t-shaped gemini compound with two tails and a preparation method and application thereof

Abstract

This invention provides a T-type twin-tailed amphiphilic compound, its preparation method, and its applications, relating to the field of polymer materials technology. The T-type twin-tailed amphiphilic compound has the structure shown in general formula (I). Its synthesis method includes: preparing a dimer containing hydrophobic blocks and isocyanate ends; reacting the dimer with a capping agent to obtain a dimer intermediate; and subjecting the secondary hydroxyl group at the center of the dimer intermediate to an addition reaction with ethylene oxide, propylene oxide, or a mixture thereof to form a hydrophilic block. It can be used as a dispersant in the preparation of coatings, inks, plastic masterbatches, or cosmetics. The T-type twin-tailed amphiphilic compound provided by this invention can be used as a dispersant for organic pigments and inks in the coatings industry. Pigment dispersion formulations using this structure exhibit good dispersibility, uniform color distribution, small particle size, strong anti-flocculation ability, and significantly improved tinting strength and film-forming quality in practical applications.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to a T-type twin-tailed amphiphilic compound, its preparation method, and its applications. Background Technology

[0002] In industries such as coatings, inks, plastic masterbatches, and cosmetics, pigment dispersion is a crucial factor determining the final color, stability, rheological properties, and optical properties of the product. A good dispersant can effectively prevent pigment particle aggregation and sedimentation, improving tinting strength, gloss, and storage stability.

[0003] Currently, commonly used dispersants mainly include small molecule surfactants, polymeric dispersants, and comb-shaped or block-structured polymeric compounds. Among them, small molecule surfactants, although lower in cost, are often prone to desorption during storage, leading to reflocculation of the dispersion system. Traditional polymeric dispersants, while possessing certain steric hindrance effects, often struggle to balance anchoring strength with the extensibility of solvated chains, especially in systems containing organic pigments or high solids content, frequently exhibiting problems such as high viscosity, poor flowability, and thickening after thermal storage.

[0004] In recent years, block or graft dispersants with amphiphilic structures have attracted attention. They adsorb onto pigment surfaces via hydrophobic segments, while hydrophilic segments extend into the medium to form a steric barrier. However, many existing products still have the following shortcomings: limited compatibility in polar or nonpolar media; decreased dispersion stability during long-term storage, manifested as increased particle size and viscosity; poor versatility for pigments of different polarities; and complex synthesis steps, making precise structural control difficult.

[0005] Therefore, there is an urgent need in this field for a novel, controllable dispersant that is suitable for a variety of pigment systems and can maintain low viscosity, small particle size and excellent color development properties over a long period of time. Summary of the Invention

[0006] This invention provides a T-type twinned amphiphilic compound with excellent dispersibility and stability, suitable for various pigment systems.

[0007] In a first aspect, the present invention provides a T-type twinned amphiphilic compound, employing the following technical solution: A T-type twinned amphiphilic compound having the structure shown in general formula (I): (C2H5)2N-CO-NH-X-NH-CO-NH-Y-NH-CO-NH-X-NH-CO-N(C2H5)2 (I); Where X is a hydrophobic block and Y is a hydrophilic block.

[0008] Alternatively, X has the structure shown in general formula (II): -TDI-NH-CO-O-[4-(C 20 H 15 )-3-C 15 H 31 -C6H5O]-O-CO-NH-TDI- (II); R1 represents a C15-C20 straight-chain alkyl group or a C15-C20 unsaturated straight-chain hydrocarbon group containing 1-3 double bonds.

[0009] Alternatively, Y has the structure shown in general formula (III): -CH(CH2O-R2-H)-CH2- (III); R2 represents a polyoxyethylene chain, a polyoxypropylene chain, or a random or block copolymer chain of ethylene oxide and propylene oxide.

[0010] Optionally, R2 represents a block copolymer chain of ethylene oxide and propylene oxide with the structure -(PO). m -(EO) n - where m is an integer from 1 to 50 and n is an integer from 5 to 100.

[0011] Secondly, the present invention provides a method for synthesizing the aforementioned T-type twinned amphiphilic compound, employing the following technical solution: A method for synthesizing the aforementioned T-type twinned amphiphilic compound includes the following steps: Prepare a dimer containing hydrophobic blocks and isocyanate ends; The dimer containing hydrophobic blocks and isocyanates at both ends is reacted with a capping agent to obtain a dimer intermediate; The secondary hydroxyl group at the center of the dimer intermediate undergoes an addition reaction with ethylene oxide, propylene oxide, or a mixture thereof to form a hydrophilic block, thereby obtaining the T-type twinned amphiphilic compound.

[0012] Optionally, the specific preparation method of the dimer containing hydrophobic blocks and having isocyanate ends is as follows: First, 4-(tristyryl) cashew phenol was reacted with toluene diisocyanate to prepare an isocyanate-terminated prepolymer containing hydrophobic blocks. Then, 1,3-diamino-2-propanol is reacted with isocyanate-terminated prepolymer to form a dimer containing hydrophobic blocks and isocyanate at both ends; The molar ratio of 4-(tristyryl) cashew phenol to toluene diisocyanate is 1:2; the molar ratio of 1,3-diamino-2-propanol to isocyanate-terminated prepolymer is 1:2.

[0013] Optionally, the capping agent is diethylamine.

[0014] Optionally, the addition reaction involves the polymerization of ethylene oxide followed by the polymerization of propylene oxide, forming a block structure of ethylene oxide and propylene oxide.

[0015] Thirdly, the present invention provides the application of the T-type twinned amphiphilic compound as a dispersant in the preparation of coatings, inks, plastic masterbatches or cosmetics.

[0016] Fourthly, the present invention provides a pigment dispersion comprising a pigment, a liquid medium, and a dispersant, wherein the dispersant is the aforementioned T-type twinned amphiphilic compound.

[0017] In summary, the present invention has at least one of the following beneficial effects: 1. The T-tailed amphiphilic compound provided by the present invention has a symmetrical T-tailed structure. The hydrophobic block can be anchored to the pigment surface to form a strong adsorption layer; the hydrophilic block in the middle can extend fully into the aqueous phase, providing effective steric hindrance and entropy repulsion, thereby significantly inhibiting the aggregation and sedimentation of pigment particles.

[0018] 2. The T-type twinned amphiphilic compound provided by this invention has extremely low system viscosity and good flowability. It is not easy to desorb or degrade during long-term storage, and the dispersion system is not easy to coarsen or thicken. Moreover, it has wide applicability to pigments and can be used in the dispersion of organic pigments and inks in the coating industry. The resulting pigment dispersion formulation has good dispersibility, uniform color distribution, small particle size, and strong anti-flocculation ability in practical applications. Attached Figure Description

[0019] Figure 1 This is a comparison of the appearance of Sample 1 and Sample 2 in an organic pigment dispersion, where Sample 1 is on the left and Sample 2 is on the right. Figure 2 This is a comparison of the appearance of Sample 3 and Sample 4 in the inorganic pigment dispersion, where Sample 3 is on the left and Sample 4 is on the right. Detailed Implementation

[0020] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments, further clarifies the invention. Those skilled in the art should understand that the specific descriptions below are illustrative rather than restrictive, and should not be construed as limiting the scope of protection of the present invention. Example

[0021] Example 1 provides a T-type twinned amphiphilic compound, whose molecular formula contains both hydrophobic and hydrophilic blocks, thus possessing both hydrophilic and hydrophobic properties; the T-type twinned amphiphilic compound has the structure shown in the following general formula (I): (C2H5)2N-CO-NH-X-NH-CO-NH-Y-NH-CO-NH-X-NH-CO-N(C2H5)2 (I); In the above general formula (I), X is a hydrophobic block with the structure shown in general formula (II): -TDI-NH-CO-O-[4-(C 20 H 15 )-3-C 15 H 31 -C6H5O]-O-CO-NH-TDI- (II); R1 represents a C15-C20 straight-chain alkyl group or a C15-C20 unsaturated hydrocarbon group containing 1-3 double bonds.

[0022] In the above general formula (I), Y is a hydrophilic block with the structure shown in general formula (III): -CH(CH2O-R2-H)-CH2- (III); R2 represents a polyoxyethylene chain, a polyoxypropylene chain, or a random or block copolymer chain of ethylene oxide and propylene oxide.

[0023] More specifically, R2 represents a block copolymer chain of ethylene oxide and propylene oxide, with the structure -(PO). m -(EO) n - where m is an integer from 1 to 50 and n is an integer from 5 to 100.

[0024] Therefore, the complete chemical structure of the above-mentioned T-type twinned amphiphilic compound is as follows: (C2H5)2N-CO-NH-TDI-NH-CO-O-[4-(C 20 H 15 )-3-C 15 H 31 -C6H5O]-O-CO-NH-TDI-NH-CO-NH-CH(CH2O-(EO)m-(PO)nH)-CH2-NH-CO-NH-TDI-NH-CO-O-[4-(C 20 H 15 )-3-C 15 H 31 -C6H5O]-O-CO-NH-TDI-NH-CO-N(C2H5)2 A method for preparing a T-type twinned amphiphilic compound includes the following steps: Step S1: Prepare 4-(tristyryl) cashew nut alcohol.

[0025] Take a 5L dry double-necked round-bottom flask, equipped with a magnetic stirrer, a reflux condenser, and a constant-pressure dropping funnel. Connect a calcium chloride drying tube to the upper end of the condenser to isolate it from moisture in the air. Add 100 g of cashew nut shell powder and 45 g of ZnCl2 to the flask, then add 1500 mL of anhydrous tetrahydrofuran. Start stirring to dissolve or disperse the solids as much as possible. Dissolve 90 g of triphenylchloromethane in 500 mL of anhydrous tetrahydrofuran to obtain a triphenylchloromethane solution, and transfer it to the constant-pressure dropping funnel. Heat the reaction mixture to 80°C in an oil bath. Slowly add the triphenylchloromethane solution, controlling the dropping rate to be completed within 30 minutes. After the addition is complete, continue heating and refluxing at 80°C for 6-12 hours. Cool the reaction mixture to room temperature. Slowly pour the reaction solution into 5L of ice water and extract with dichloromethane (3 × 2 L). Combine the organic phases, wash with saturated brine, dry with anhydrous sodium sulfate, filter, and remove the solvent by rotary evaporation to obtain the crude product. The product was collected and purified by column chromatography, and then eluted with a gradient of petroleum ether and ethyl acetate (gradually increasing from 100% petroleum ether to 5% ethyl acetate). The solvent was removed by rotary evaporation to obtain a pale yellow to white solid or a waxy solid, which is 4-(tristyryl) cashew nut alcohol.

[0026] Step S2: Prepare -NCO-terminated 4-(tristyryl) cashew nut prepolymer.

[0027] Dry all glassware, including the round-bottom flask, condenser, and dropping funnel, thoroughly in an oven (110°C, overnight) and assemble while hot. Connect a balloon filled with inert gas to the upper end of the condenser and a mineral oil bubbler to the outlet to maintain positive pressure. Under dry conditions, accurately weigh 1.0 mol of 4-(tristyryl) cashew nut shell powder prepared in step S1 and add it to the reaction flask. Add a measured amount of anhydrous tetrahydrofuran (approximately 3-5 times the total volume of reactants) to the flask, start stirring, and allow it to dissolve completely. Use a syringe to draw 0.2% of the total mass of the reactants of catalyst DBTL and inject it into the reaction flask, continuing stirring. Transfer an accurately weighed amount of toluene diisocyanate (TDI-100, 2.0 mol) to a constant-pressure dropping funnel and dilute it with an anhydrous tetrahydrofuran of approximately the same volume as the TDI. Mix well to obtain a TDI solution, ready for dropwise addition. Continuously purge the assembled reaction system with N2 for 10-15 minutes to replace the air. Then, place the reaction flask in an ice-water bath and cool to 0-5℃. While stirring vigorously, slowly add TDI solution dropwise through a constant-pressure dropping funnel. Strictly control the dropping rate to maintain the reaction temperature below 40℃. This process takes approximately 1-2 hours. After the addition is complete, remove the ice bath and allow the reaction system to naturally warm to room temperature (approximately 25℃). Then, place it in an oil bath at 30-40℃ and continue the reaction for 8 hours to obtain -NCO-terminated 4-(tristyryl)cainol prepolymer. Place the obtained 4-(tristyryl)cainol prepolymer solid in a vacuum drying oven and dry it thoroughly to constant weight at room temperature or lower. Then seal it and store it in a refrigerator (-20℃) or freezer, and label it. The reaction process is monitored by measuring its infrared spectrum using FT-IR. When the characteristic peak of the phenolic hydroxyl group (~3200-3600 cm⁻¹) is reached... -1 The isocyanate characteristic peak (~2270 cm⁻¹) has largely disappeared. -1 The intensity of the reaction no longer decreases and stabilizes near the theoretical value, indicating that the reaction has been completed.

[0028] Step S3: Prepare -NCO-terminated dimers.

[0029] Accurately weigh 2.0 mol of the -NCO-terminated 4-(tristyryl) cashew phenol prepolymer prepared in step S2 and place it in a reaction flask; add an appropriate amount of anhydrous tetrahydrofuran, start stirring, and let it dissolve completely to obtain a prepolymer solution. Heat the prepolymer solution to 60°C using an oil bath and maintain the temperature. In another dry flask, accurately weigh 1.0 mol of 1,3-diamino-2-propanol and dissolve it in a small amount of anhydrous tetrahydrofuran to prepare a tetrahydrofuran solution of 1,3-diamino-2-propanol with a mass concentration of about 10-20%. Transfer this solution to a constant pressure dropping funnel. Under vigorous stirring, slowly and dropwise add the tetrahydrofuran solution of 1,3-diamino-2-propanol to the prepolymer solution. The dropping rate should not be too fast (the dropping rate should be controlled within 1 hour). Maintain the reaction temperature at 60-70℃. After the addition is complete, continue stirring at 60-70℃ for 4 hours. Stop the reaction, add a small amount of anhydrous methanol, and stir for 30 minutes to quench any residual -NCO groups. Cool the reaction solution to room temperature, and while stirring vigorously, pour in a large amount of deionized water. The product will precipitate out as a fibrous or flocculent solid. Collect the solid by filtration using a Buchner funnel, and wash the solid repeatedly with methanol to thoroughly remove the solvent tetrahydrofuran and any unreacted impurities. After filtration again, transfer the filter cake to a watch glass and place it in a vacuum drying oven at 50-60℃ for 24-48 hours until constant weight is obtained, yielding a white to pale yellow solid product, which is an -NCO-terminated dimer. The reaction process is monitored by FT-IR showing the disappearance of the -NCO peak and the appearance of a urea bond C=O peak (~1640 cm⁻¹). -1 ) and a strong and broad hydroxyl (OH) peak (~3200-3500 cm⁻¹) -1 ).

[0030] Step S4: Prepare the dimer intermediate.

[0031] Place all the -NCO-terminated dimers prepared in step S3 into a dry round-bottom flask; add an appropriate amount of anhydrous tetrahydrofuran, start stirring, and let it dissolve completely to obtain a dimer solution; install a reflux condenser, the upper end of which can be connected to a bubbler filled with mineral oil to observe the reaction and absorb waste gas; place the reaction flask in an ice-water bath and cool to 0-5℃. Low temperature can control the reaction rate and prevent it from being too vigorous; according to the calculated amount, mix excess diethylamine (2.2 mol, 10% excess) with an equal volume of anhydrous tetrahydrofuran to obtain a diethylamine solution and transfer it to a constant pressure dropping funnel; under vigorous stirring, slowly add the diethylamine solution dropwise to the dimer solution. Control the dropping rate and maintain the reaction temperature below 30°C; after the dropping is complete, remove the ice-water bath and allow the reaction solution to slowly warm to room temperature, continuing to stir the reaction for 2-4 hours at room temperature; monitor the reaction using FT-IR spectroscopy, taking a small amount of the reaction solution with a dropper and applying it to a KBr salt plate for measurement, the endpoint being the characteristic absorption peak of -NCO (~2270 cm⁻¹). -1 The peak of the C=O stretching vibration of substituted urea (~1640-1660 cm⁻¹) completely disappears, and at the same time, the peak of the C=O stretching vibration of substituted urea appears. -1 ) and NH stretching vibration peak (~3320 cm⁻¹) -1 After confirming that the reaction is complete, the reaction solution is concentrated on a rotary evaporator to remove most of the solvent and excess diethylamine. The concentrated product is then added dropwise to a large amount of n-hexane or petroleum ether under vigorous stirring. The product will precipitate out as a solid or viscous substance. The precipitate is collected by filtration or decantation. The final product is dried in a vacuum drying oven at 40-50°C for 24-48 hours to obtain the dimer intermediate.

[0032] Step S5: Preparation of T-type twin-tailed amphiphilic compounds: Thoroughly clean the stainless steel high-pressure reactor and dry it at 100°C; add the dried dimer intermediate and anhydrous toluene (toluene mass is 3-4 times the mass of the dimer intermediate) prepared in step S4 into the reactor; add 0.15% by mass of the reactants (including the dimer intermediate and anhydrous toluene) of KOH catalyst, ensuring that the stir bar can rotate smoothly; seal the reactor, open the exhaust valve, and thoroughly remove air and oxygen from the reactor by repeatedly evacuating and filling with nitrogen (at least 3 times); close the exhaust valve, introduce nitrogen until the pressure reaches 0.4 MPa, close the inlet valve, and observe whether the pressure gauge reading remains stable within 1 hour to check the airtightness of the system. After confirming there are no leaks, vent the nitrogen gas; start the stirring and heating system to raise the temperature inside the reactor to 100-110℃, so that the intermediate is fully dissolved and the catalyst is activated; based on the molar number of the dimerizing intermediate, inject 20-60 times the molar number of the dimerizing intermediate into the reactor by gravimetric method (i.e., to make the degree of polymerization n 20-60), maintain the reaction temperature at 120-150℃, and stir the reaction for 2-4 hours under these conditions. The reaction endpoint was determined by observing the pressure drop (when the pressure drops to a stable value and no longer decreases, it indicates that the EO has been basically consumed); the exhaust valve was opened, and the pressure inside the vessel was reduced to -0.1 MPa and maintained for 0.5 h by vacuuming, and the unreacted EO was extracted; in the same way as the above reaction, propylene oxide with a molar amount of 5 times that of the dimer intermediate (i.e., to make the degree of polymerization m 5) was injected to carry out the reaction; after the reaction was completed, the vessel was aged for 2 h, and after neutralization, adsorption, dehydration, and degassing, it was filtered with a leaf filter and the filtrate was distilled under reduced pressure to obtain the T-type twin-tailed amphiphilic compound.

[0033] Comparative Example 1: Comparative Example 1 uses BASF's Dispex® Ultra PA 4560.

[0034] Performance testing: To verify the excellent performance of the T-type twinned amphiphilic compound provided in Example 1 of the present invention as a dispersant, it was compared with Comparative Example 1 according to the following application formulation and test method.

[0035] Following the formulations shown in Table 1, the above components were mixed and dispersed using the same grinding and dispersion process until dispersion equilibrium was reached, yielding samples 1-4. The prepared samples were then visually inspected to assess their flow properties.

[0036] Table 1. Formulations of Samples 1-4

[0037] Figure 1This is a comparison of the appearance of Sample 1 and Sample 2 in an organic pigment dispersion, where Sample 1 is on the left and Sample 2 is on the right. Figure 2 This is a comparison of the appearance of Sample 3 and Sample 4 in the inorganic pigment dispersion, where Sample 3 is on the left and Sample 4 is on the right. Figure 1 and Figure 2 As shown, for both organic and inorganic pigments, samples 1 and 3, using the compound of Example 1 of this invention as a dispersant, exhibited excellent surface flowability, with a thin and uniform texture. In contrast, samples 2 and 4, using the dispersant of Comparative Example 1, were significantly more viscous and had poorer flowability. This indicates that the compound of this invention can more effectively reduce system viscosity and improve processing rheology.

[0038] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A T-type twinned amphiphilic compound, characterized in that, It has the structure shown in the following general formula (I): (C2H5)2N-CO-NH-X-NH-CO-NH-Y-NH-CO-NH-X-NH-CO-N(C2H5)2 (I); Where X is a hydrophobic block and Y is a hydrophilic block.

2. The T-type twinned amphiphilic compound according to claim 1, characterized in that, X has the structure shown in general formula (II): -TDI-NH-CO-O-[4-(C 20 A 15 )-3-C 15 A 31 -C6H5O]-O-CO-NH-TDI-(II); R1 represents a C15-C20 straight-chain alkyl group or a C15-C20 unsaturated straight-chain hydrocarbon group containing 1-3 double bonds.

3. The T-type twinned amphiphilic compound according to claim 1, characterized in that, Y has the structure shown in general formula (III): -CH(CH2O-R2-H)-CH2- (III); R2 represents a polyoxyethylene chain, a polyoxypropylene chain, or a random or block copolymer chain of ethylene oxide and propylene oxide.

4. The T-type twinned amphiphilic compound according to claim 3, characterized in that, R2 represents a block copolymer chain of ethylene oxide and propylene oxide, with the structure -(PO). m -(EO) n - where m is an integer from 1 to 50 and n is an integer from 5 to 100.

5. A method for synthesizing a T-type twinned amphiphilic compound according to any one of claims 1-4, characterized in that, Includes the following steps: Prepare a dimer containing hydrophobic blocks and isocyanate ends; The dimer containing hydrophobic blocks and isocyanates at both ends is reacted with a capping agent to obtain a dimer intermediate; The secondary hydroxyl group at the center of the dimer intermediate undergoes an addition reaction with ethylene oxide, propylene oxide, or a mixture thereof to form a hydrophilic block, thereby obtaining the T-type twinned amphiphilic compound.

6. The method for synthesizing the T-type twinned amphiphilic compound according to claim 5, characterized in that, The specific preparation method of the dimer containing hydrophobic blocks and with isocyanates at both ends is as follows: First, 4-(tristyryl) cashew phenol was reacted with toluene diisocyanate to prepare an isocyanate-terminated prepolymer containing hydrophobic blocks. Then, 1,3-diamino-2-propanol is reacted with isocyanate-terminated prepolymer to form a dimer containing hydrophobic blocks and isocyanate at both ends; The molar ratio of 4-(tristyryl) cashew phenol to toluene diisocyanate is 1:2; the molar ratio of 1,3-diamino-2-propanol to isocyanate-terminated prepolymer is 1:

2.

7. The method for synthesizing the T-type twinned amphiphilic compound according to claim 5, characterized in that, The capping agent is diethylamine.

8. The method for synthesizing the T-type twinned amphiphilic compound according to claim 5, characterized in that, The addition reaction involves the polymerization of ethylene oxide followed by the polymerization of propylene oxide, forming a block structure of ethylene oxide and propylene oxide.

9. The use of the T-type twinned amphiphilic compound according to any one of claims 1-4 as a dispersant in the preparation of coatings, inks, plastic masterbatches or cosmetics.

10. A pigment dispersion, characterized in that, It comprises a pigment, a liquid medium, and a dispersant, wherein the dispersant is a T-type twinned amphiphilic compound as described in any one of claims 1-4.

Images