Process for the preparation of a dual parent radical initiator

Abstract

This invention discloses a method for preparing an amphiphilic free radical initiator. The method involves preparing a solution of oleic acid polyoxyethylene ester or stearic acid polyoxyethylene ester and triethylamine / dichloroethane, then slowly adding the triethylamine / dichloroethane solution dropwise to the solution. The reaction is carried out at room temperature, and after the oxaloyl chloride solution is completely added, the reaction continues for 30 minutes. Next, a tert-butyl hydroperoxide / dichloroethane solution is slowly added dropwise, and the reaction continues at room temperature, continuing for another 60 minutes. The dichloroethane solvent in the reaction solution is removed under reduced pressure at room temperature. Then, n-hexane is added, and the triethylamine hydrochloride solid is filtered out. The obtained filtrate is then filtered again to remove the n-hexane solvent under reduced pressure at room temperature, yielding the amphiphilic peroxide product.

Description

Technical Field

[0001] This invention relates to the field of free radical initiators, specifically a method for preparing an amphiphilic free radical initiator. Background Technology

[0002] A free radical initiator is a compound that produces free radicals through homolytic cleavage of covalent bonds. Due to the high reactivity of free radicals, they can undergo polymerization, grafting, cross-linking, and other reactions by opening carbon-carbon double bonds or by free radical hydrogen abstraction reactions.

[0003] Traditional free radical initiators are generally classified into two main categories: water-soluble and oil-soluble. To broaden the application range of free radical initiators, amphiphilic free radical initiators with hydrophilic-lipophilic structures have emerged. Due to their special chain structure, unique properties, and wide range of applications, amphiphilic polymers act as both initiators and emulsifiers in soap-free emulsion polymerization, simplifying the polymerization process, facilitating industrial production, and allowing the hydrophilic and lipophilic segments generated during decomposition to remain as functional groups at the polymer chain ends, thus achieving polymer functionalization. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing an amphiphilic free radical initiator.

[0005] The above objectives are achieved through the following scheme:

[0006] A method for preparing an amphiphilic free radical initiator, characterized by comprising the following steps:

[0007] (1) Dissolve the terminal hydroxyl amphiphilic molecule and triethylamine in dichloroethane to obtain solution A, dissolve oxaloyl chloride in dichloroethane to obtain solution B, and dissolve tert-butyl hydroperoxide in dichloroethane to obtain solution C;

[0008] (2) Stir solution B while slowly adding solution A dropwise, maintaining the reaction temperature at room temperature. After solution A has been added, continue stirring the reaction solution for 30-35 minutes.

[0009] (3) Then slowly add solution C dropwise into the reaction solution obtained in step (2), maintain the reaction temperature at room temperature, and continue stirring the reaction solution for 60-65 minutes after solution C has been added.

[0010] (4) Remove the dichloroethane solvent from the reaction solution obtained in step (3) at room temperature and under reduced pressure. After the dichloroethane solvent is removed, add n-hexane, stir, filter, and keep the filtrate for later use. The obtained solid crystal is triethylamine hydrochloride.

[0011] (5) Extract the n-hexane solvent from the filtrate under reduced pressure at room temperature. After the n-hexane solvent is removed, filter again to obtain the amphiphilic peroxide product.

[0012] The method for preparing an amphiphilic free radical initiator is characterized in that the mass ratio of terminal hydroxyl amphiphilic molecule: oxaloyl chloride: tert-butyl hydroperoxide: triethylamine is 1:1-1.2:1-1.2:2-2.1.

[0013] The method for preparing an amphiphilic free radical initiator is characterized in that, in solution A of step (1), the total volume of the terminal hydroxyl amphiphilic molecule and triethylamine is in a volume ratio of 1:3-5 to that of dichloroethane.

[0014] The method for preparing an amphiphilic free radical initiator is characterized in that, in solution B of step (1), the volume ratio of oxaloyl chloride to dichloroethane is 1:5-10.

[0015] The method for preparing an amphiphilic free radical initiator is characterized in that, in solution C in step (1), the volume ratio of tert-butyl hydroperoxide to dichloroethane is 1:3-5.

[0016] The method for preparing an amphiphilic free radical initiator is characterized in that the terminal hydroxyl amphiphilic molecules are polyoxyethylene oleate and polyoxyethylene stearate, and the number of polyoxyethylene structural units n in the amphiphilic molecules is 3-10.

[0017] The method for preparing an amphiphilic free radical initiator is characterized in that,

[0018] The structural formula of oleic acid polyoxyethylene ester is:

[0019]

[0020] The method for preparing an amphiphilic free radical initiator is characterized in that the structural formula of polyoxyethylene stearate is:

[0021]

[0022] The method for preparing an amphiphilic free radical initiator is characterized in that the obtained amphiphilic free radical initiator contains a lipophilic segment-a hydrophilic segment-peroxide group, with the following structural formula:

[0023]

[0024] Prepare a solution of oleic acid polyoxyethylene ester or stearic acid polyoxyethylene ester and triethylamine / dichloroethane, then slowly add it dropwise to a solution of oxaloyl chloride / dichloroethane. React at room temperature. After the oxaloyl chloride solution is completely added, continue to react for 30 minutes. Then, slowly add a solution of tert-butyl hydroperoxide / dichloroethane. React at room temperature. After the tert-butyl hydroperoxide solution is completely added, continue to react for 60 minutes. Remove the dichloroethane solvent from the reaction solution under reduced pressure at room temperature. Then, add n-hexane and filter out the triethylamine hydrochloride solid. Remove the n-hexane solvent from the filtrate under reduced pressure at room temperature and filter again to obtain the amphiphilic peroxide product.

[0025] The beneficial effects of this invention are as follows:

[0026] (1) It simplifies the emulsion polymerization process;

[0027] (2) Reduced the residue of free emulsifier in the polymer;

[0028] (3) Free radical polymerization is used to achieve the amphiphilic structure of the polymer. Attached Figure Description

[0029] Figure 1 This is a synthetic route diagram for amphiphilic molecular free radical initiators;

[0030] Figure 2 The images show the FTIR spectra of OEO-5, TBHP, and the amphiphilic initiator. Curve 1 is the FTIR spectrum of TBHP, curve 2 is the spectrum of OEO-5, and curve 3 is the spectrum of TBHP. Detailed Implementation

[0031] Example 1

[0032] according to Figure 1 The synthetic route for the amphiphilic molecular radical initiator is shown below:

[0033] 1) Add 5 mL (0.012 mol / L) of oleic acid polyoxyethylene ester (n=3, density: 1.034 g / cm³). 3 3.4 mL of triethylamine (density: 0.728 g / cm³) 3 Dissolve the oxaloyl chloride in 10 mL of dichloroethane to obtain solution A. Add 1.02 mL (0.012 mol / L) of oxaloyl chloride (density: 1.488 g / cm³) to the solution. 3 Solution B is obtained by dissolving 1.15 mL of tert-butyl hydroperoxide (density: 0.937 g / cm³) in 6 mL of dichloroethane. 3 Dissolve it in 3.5 mL of dichloroethane to obtain solution C;

[0034] 2) Stir solution B while slowly adding solution A dropwise, maintaining the reaction temperature at room temperature. After solution A has been added, continue stirring the reaction solution for 30 minutes.

[0035] 3) Then slowly add solution C dropwise into the above reaction solution, maintaining the reaction temperature at room temperature. After solution C has been added, continue stirring the reaction solution for 60 minutes.

[0036] 4) Remove the dichloroethane solvent from the reaction solution under reduced pressure at room temperature. After the dichloroethane solvent is removed, add n-hexane, stir, and filter. The solid crystals are triethylamine hydrochloride.

[0037] 5) Extract the n-hexane solvent from the filtrate under reduced pressure at room temperature. After the n-hexane solvent is removed, filter again to obtain the amphiphilic peroxide product.

[0038] Example 2

[0039] according to Figure 1 The synthetic route for the amphiphilic molecular radical initiator is shown below:

[0040] 1) Add 5 mL (0.012 mol / L) of polyoxyethylene stearate (n=3, density: 0.964 g / cm³). 3 3.4 mL of triethylamine (density: 0.728 g / cm³) 3 Dissolve the oxaloyl chloride in 10 mL of dichloroethane to obtain solution A. Add 1.02 mL (0.012 mol / L) of oxaloyl chloride (density: 1.488 g / cm³) to the solution. 3 Solution B is obtained by dissolving 1.15 mL of tert-butyl hydroperoxide (density: 0.937 g / cm³) in 6 mL of dichloroethane. 3 Dissolve it in 3.5 mL of dichloroethane to obtain solution C;

[0041] 2) Stir solution B while slowly adding solution A dropwise, maintaining the reaction temperature at room temperature. After solution A has been added, continue stirring the reaction solution for 30 minutes.

[0042] 3) Then slowly add solution C dropwise into the above reaction solution, maintain the reaction temperature at room temperature, and continue stirring the reaction solution for 60 minutes after solution A has been added.

[0043] 4) Remove the dichloroethane solvent from the reaction solution under reduced pressure at room temperature. After the dichloroethane solvent is removed, add n-hexane, stir, and filter. The solid crystals are triethylamine hydrochloride.

[0044] 5) Extract the n-hexane solvent from the filtrate under reduced pressure at room temperature. After the n-hexane solvent is removed, filter again to obtain the amphiphilic peroxide product.

[0045] Example 3

[0046] according to Figure 1 The synthetic route for the amphiphilic molecular radical initiator is shown below:

[0047] 1) Add 5 mL (0.01 mol / L) of oleic acid polyoxyethylene ester (n=5, density: 1.034 g / cm³) 3 2.9 mL of triethylamine (density: 0.728 g / cm³) 3 Dissolve the oxaloyl chloride in 10 mL of dichloroethane to obtain solution A. Add 0.85 mL (0.01 mol / L) of oxaloyl chloride (density: 1.488 g / cm³). 3 Solution B is obtained by dissolving 0.96 mL of tert-butyl hydroperoxide (density: 0.937 g / cm³) in 8.5 mL of dichloroethane. 3 Dissolve it in 4.5 mL of dichloroethane to obtain solution C;

[0048] 2) Stir solution B while slowly adding solution A dropwise, maintaining the reaction temperature at room temperature. After solution A has been added, continue stirring the reaction solution for 30 minutes.

[0049] 3) Then slowly add solution C dropwise into the above reaction solution, maintaining the reaction temperature at room temperature. After solution C has been added, continue stirring the reaction solution for 60 minutes.

[0050] 4) Remove the dichloroethane solvent from the reaction solution under reduced pressure at room temperature. After the dichloroethane solvent is removed, add n-hexane, stir, and filter. The solid crystals are triethylamine hydrochloride.

[0051] 5) Extract the n-hexane solvent from the filtrate under reduced pressure at room temperature. After the n-hexane solvent is removed, filter again to obtain the amphiphilic peroxide product.

[0052] The amphiphilic molecular free radical initiator prepared according to Example 3 Figure 2 The figures show the FTIR spectra of oleic acid polyoxyethylene ester (OEO-5), tert-butyl hydroperoxide (TBHP), and an amphiphilic initiator, respectively. The figures show that the amphiphilic initiator and TBHP show a peak at 843 cm⁻¹. -1 There is a distinct absorption peak for peroxide bonds (OO) at this location, while OEO-5 does not show a corresponding peak at this location.

Claims

1. A method for preparing an amphiphilic free radical initiator, characterized in that, Includes the following steps: (1) Dissolve the terminal hydroxyl amphiphilic molecule and triethylamine in dichloroethane to obtain solution A, dissolve oxaloyl chloride in dichloroethane to obtain solution B, and dissolve tert-butyl hydroperoxide in dichloroethane to obtain solution C; (2) Stir solution B while slowly adding solution A dropwise, maintaining the reaction temperature at room temperature. After solution A has been added, continue stirring the reaction solution for 30-35 minutes. (3) Then slowly add solution C dropwise into the reaction solution obtained in step (2), maintain the reaction temperature at room temperature, and continue stirring the reaction solution for 60-65 minutes after solution C has been added. (4) Remove the dichloroethane solvent from the reaction solution obtained in step (3) at room temperature and under reduced pressure. After the dichloroethane solvent is removed, add n-hexane, stir, filter, and keep the filtrate for later use. The obtained solid crystal is triethylamine hydrochloride. (5) Extract the n-hexane solvent from the filtrate under reduced pressure at room temperature. After the n-hexane solvent is removed, filter again to obtain the amphiphilic peroxide product. The mass ratio of the terminal hydroxyl amphiphilic molecule: oxaloyl chloride: tert-butyl hydroperoxide: triethylamine is 1:1-1.2:1-1.2:2-2.1; The terminal hydroxyl amphiphilic molecule is oleic acid polyoxyethylene ester or stearic acid polyoxyethylene ester, and the number of polyoxyethylene structural units n in its amphiphilic molecule is 3-10. The structural formula of oleic acid polyoxyethylene ester is: The structural formula of polyoxyethylene stearate is: .

2. The method for preparing an amphiphilic free radical initiator according to claim 1, characterized in that, In solution A described in step (1), the total volume ratio of the terminal hydroxyl amphiphilic molecule and triethylamine to the volume ratio of dichloroethane is 1:3-5.

3. The method for preparing an amphiphilic free radical initiator according to claim 1, characterized in that, In solution B described in step (1), the volume ratio of oxalyl chloride to dichloroethane is 1:5-10.

4. The method for preparing an amphiphilic free radical initiator according to claim 1, characterized in that, In solution C described in step (1), the volume ratio of tert-butyl hydroperoxide to dichloroethane is 1:3-5.

Images