CN112430278A - Quaternary phosphonium salt type organic silicon latex and preparation method thereof - Google Patents
Quaternary phosphonium salt type organic silicon latex and preparation method thereof Download PDFInfo
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- CN112430278A CN112430278A CN202011338149.2A CN202011338149A CN112430278A CN 112430278 A CN112430278 A CN 112430278A CN 202011338149 A CN202011338149 A CN 202011338149A CN 112430278 A CN112430278 A CN 112430278A
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Abstract
The invention relates to quaternary phosphonium salt type organic silicon latex which comprises the following components in parts by mass: 10-20 parts of quaternary phosphonium salt type organic silicon emulsion, 65-80 parts of latex, 3-6 parts of coupling agent, 2-5 parts of stabilizing agent, 1-3 parts of initiator, 1-3 parts of coagulant and 1-2 parts of foaming agent; the quaternary phosphonium salt is adopted to modify the organic silicon emulsion to prepare the organic silicon emulsion with positive charges, then the latex with negative charges is modified by a heterocoagulation grafting method, a proper catalyst is selected, and the quaternary phosphonium salt type organic silicon latex is synthesized by controlling a formula and a synthesis process; the surface of the prepared latex product has the excellent performance of organic silicon, the water resistance and the solvent resistance are greatly improved, and quaternary phosphonium salt is introduced, so that the latex product has lasting antibacterial, mildew-proof and deodorant effects, is safe and reliable to a human body, does not pollute the environment, and improves the grade of the product.
Description
Technical Field
The invention relates to the field of latex, is applied to sponge, and particularly relates to quaternary phosphonium salt type organic silicon latex and a preparation method thereof.
Background
The latex pillow and the latex mattress can be slowly oxidized and yellowed after being used for a long time, and in addition, bacteria are easily bred on the surface to cause mildewing in a humid environment due to the reasons of air impermeability, microorganism aggregation or synthetic latex and the like; if effective in preventing the development of mold in latex products, it is necessary to use a bactericide comprising an organometallic compound, an organic sulfur compound, an organic chlorine compound or other organic compounds.
However, latex sponges treated with organometallic compounds are harmful to humans; the quaternary ammonium salt and quaternary phosphonium salt organic compounds have cationic surface activity and can adsorb microorganisms with negative electricity on the surface to lose the activity, so that the bactericidal and mildewproof effects are better, and meanwhile, the low foamability, the low dosage, the low toxicity, the good compatibility and the wide application range are paid more and more attention.
In addition, the organosilicon material has hydrophobicity, weather resistance, lower surface energy and soft molecular chain, and has wide application prospect in the field of high polymer materials.
Disclosure of Invention
Aiming at the defects that the existing latex sponge is easy to yellow and breed mould, the quaternary phosphonium salt type organic silicon is added to develop a new generation of solvent-resistant, water-resistant, antibacterial and mould-proof latex sponge, and the quaternary phosphonium salt type organic silicon latex has a huge development prospect for the multifunctional development of latex pillow, latex mattress and other products.
The technical principle of the invention is as follows: the quaternary phosphonium salt modified organosilicon emulsion is used to prepare the organosilicon emulsion with positive charges, the latex with negative charges is modified by a heterocoagulation grafting method, a proper catalyst is selected, and the quaternary phosphonium salt type organosilicon emulsion is synthesized by controlling a formula and a synthesis process.
The technical content is that the quaternary phosphonium salt type organic silicon latex comprises the following components in parts by mass: 10-20 parts of quaternary phosphonium salt type organic silicon emulsion, 65-80 parts of latex, 3-6 parts of coupling agent, 2-5 parts of stabilizing agent, 1-3 parts of initiator, 1-3 parts of coagulant and 1-2 parts of foaming agent.
Preferably, the quaternary phosphonium salt type organic silicon latex comprises the following components in parts by mass: 15 parts of quaternary phosphonium salt type organic silicon emulsion, 70 parts of latex, 5 parts of coupling agent, 3 parts of stabilizing agent, 2 parts of initiator, 3 parts of coagulant and 2 parts of foaming agent.
A preparation method of quaternary phosphonium salt type organic silicon latex comprises the following steps:
(1) 3-bromopropyl triphenyl phosphonium salt preparation: adding a certain amount of triphenylphosphine, 1, 3-dibromopropane and a reaction solvent into a three-neck flask reactor, wherein the molar ratio of triphenylphosphine to 1, 3-dibromopropane is 1:1, stirring, heating, refluxing and reacting for 8-24 h at 120-140 ℃, cooling, filtering, washing with 50-100 mL of diethyl ether, vacuum drying at 70-85 ℃ to obtain crude 3-bromopropyl triphenyl quaternary phosphonium salt, recrystallizing and purifying, and vacuum drying at 70-85 ℃ for later use;
(2) preparation of organosilicon quaternary phosphonium salt: taking excessive coupling agent KH550, 3-bromopropyltriphenyl quaternary phosphonium salt, an acid-binding agent and a reaction solvent, wherein the molar ratio of the coupling agent KH550, 3-bromopropyltriphenyl quaternary phosphonium salt to the acid-binding agent is 2:1:1, adding the coupling agent KH550, 3-bromopropyltriphenyl quaternary phosphonium salt to the acid-binding agent into a three-neck flask reactor, adding a catalyst, stirring, heating, refluxing and reacting for 4-6 h at the temperature of 60-80 ℃, filtering while the reaction is hot, evaporating the reaction solvent, cooling to room temperature to obtain yellow oily liquid, adding diethyl ether, separating out a white solid, recrystallizing and purifying, washing the diethyl ether for 2-3 times, and performing vacuum drying at the temperature of 70-85 ℃ for later use;
(3) preparation of quaternary phosphonium salt type silicone emulsion: adding organic silicon quaternary phosphonium salt, tween 80, an emulsifier and deionized water into a three-neck flask reactor, stirring and reacting for 0.5-1 h at 40-60 ℃, heating to 80 ℃, adding a certain amount of potassium hydroxide solution, reacting for 3-5 h at constant temperature, cooling, and neutralizing for later use;
(4) preparing quaternary phosphonium salt type organic silicon emulsion graft modified latex: taking a certain amount of latex, a coupling agent and a stabilizing agent, stirring for 15-45 min, heating to 60 ℃, dropwise adding the quaternary phosphonium salt type organic silicon latex into a constant-pressure funnel, dropwise adding for 0.5-1 h, then continuously dropwise adding an initiator, reacting for 4-6 h, adding a foaming agent and a coagulant, performing injection molding, foaming, vulcanizing and drying to obtain the quaternary phosphonium salt type organic silicon latex.
Further, the reaction solvent in the step (1) is one of toluene, xylene or DMF, and the three-neck flask reactor consists of a three-neck flask, a thermometer, a stirrer and a condenser pipe; in the recrystallization purification process, the solvent is absolute ethyl alcohol.
Further, the reaction solvent in the step (2) is absolute ethyl alcohol, and 3-bromopropyl triphenyl phosphonium salt is dissolved in a hot ethyl alcohol solvent in advance; the acid-binding agent in the step (2) is one of triethylamine or potassium carbonate; the catalyst in the step (2) is potassium iodide, and the molar ratio of the dosage of the potassium iodide to the dosage of the 3-bromopropyltriphenyl phosphonium salt is 1: 0.01-0.02.
Further, the three-neck flask reactor is placed in an oil bath tank with an ultrasonic reactor, the power of the ultrasonic reactor is 20kHz, and the reflux reaction is carried out under the protection of nitrogen.
Further, in the reflux reaction in the step (2), one of ethanol solutions of the 3-bromopropyltriphenyl quaternary phosphonium salt is added at one time or dropwise in a feeding mode of the 3-bromopropyltriphenyl quaternary phosphonium salt; in the recrystallization purification process in the step (2), the solvent is one or a combination of two of dichloromethane and n-hexane.
Further, the emulsifier in step (3) is cetyl trimethyl ammonium bromide, which reduces the interfacial tension between the dispersed phase and the continuous phase and makes them easier to emulsify; the mass concentration of the potassium hydroxide solution is 8-15%; the neutralization reaction is to drop glacial acetic acid for neutralization until the pH value is 6-8.
Further, the latex in the step (4) is one or a combination of two of natural latex and synthetic latex; the coupling agent in the step (4) is vinyl trimethylsilane; the stabilizer is sodium bisulfite, which can enhance the surface charge, protective layer and hydration degree of the latex particles; the initiator is ammonium persulfate; the foaming agent is one of lauric acid, sodium palmitate and sodium myristate; the coagulant is a delayed coagulant, namely sodium silicofluoride, so that the latex is slowly gelled; the vulcanization process parameters are as follows: the vulcanizing temperature is 100-130 ℃, the vulcanizing time is 5-15 min, and the vulcanizing temperature is 70-100 ℃, the drying time is 10-25 min.
Has the advantages that: according to the quaternary phosphonium salt type organic silicon latex and the preparation method thereof, the quaternary phosphonium salt modified organic silicon is adopted to modify the latex, the surface of the prepared latex product has the excellent performance of the organic silicon, the water resistance and the solvent resistance are greatly increased, and meanwhile, the quaternary phosphonium salt is introduced, so that the latex product has lasting antibacterial, mildew-proof and deodorant effects, is safe and reliable to a human body, does not pollute the environment, and improves the grade of the product.
Drawings
FIG. 1 is a schematic diagram of a three-necked flask reactor.
Detailed Description
The quaternary phosphonium salt type organic silicon latex is prepared from the following raw materials in parts by mass: 15 parts of quaternary phosphonium salt type organic silicon emulsion, 70 parts of latex, 5 parts of coupling agent, 3 parts of stabilizing agent, 2 parts of initiator, 3 parts of coagulant and 2 parts of foaming agent. The latex is natural latex, the coupling agent is vinyl trimethylsilane, the stabilizing agent is sodium bisulfite, the initiator is ammonium persulfate, the coagulant is slow coagulant sodium silicofluoride, the foaming agent is sodium myristate, and the specific preparation method of the quaternary phosphonium salt type organic silicon latex is as follows:
(1) step 1: adding triphenylphosphine, 1, 3-dibromopropane and a reaction solvent in a molar ratio of 1:1 into a three-neck flask reactor, stirring, heating, refluxing and reacting for 12 h under the protection of nitrogen at 130 ℃, cooling, filtering, washing with 100 mL diethyl ether, and vacuum drying at 80 ℃ to obtain a crude product of 3-bromopropyl triphenyl quaternary phosphonium salt, recrystallizing and purifying the crude product of the quaternary phosphonium salt with absolute ethyl alcohol, and vacuum drying at 80 ℃ for later use;
(2) step 2: adding a coupling agent KH550, a 3-bromopropyltriphenyl phosphonium salt, an acid-binding agent triethylamine and a reaction solvent in a molar ratio of 2:1:1 into a three-necked flask reactor, adding a catalyst potassium iodide, controlling the reaction temperature to be 70 ℃, stirring, heating, refluxing, reacting for 6 hours under the protection of nitrogen, filtering while the reaction is hot after the reaction is finished, evaporating the reaction solvent, cooling to room temperature to obtain yellow oily liquid, adding diethyl ether, separating out a white solid, performing recrystallization purification by using dichloromethane and n-hexane, washing the diethyl ether for 2-3 times, and performing vacuum drying at 75 ℃ for later use;
(3) and step 3: adding organic silicon quaternary phosphonium salt, tween 80, an emulsifier cetyl trimethyl ammonium bromide and deionized water into a three-neck flask reactor, stirring and reacting for 1 h at 40 ℃, heating to 80 ℃, adding 3 parts by mass of 10% potassium hydroxide solution, reacting for 5 h at constant temperature, cooling, and dropwise adding glacial acetic acid to neutralize the pH value to about 7 for later use;
(4) and 4, step 4: and (2) taking the natural latex, the vinyltrimethylsilane and the sodium bisulfite, stirring for 30 min, heating to 60 ℃, dropwise adding the quaternary phosphonium salt type organosilicon emulsion into a constant-pressure funnel, dropwise adding the quaternary phosphonium salt type organosilicon emulsion for 0.5 h, continuously dropwise adding an ammonium persulfate saturated solution, reacting for 6 h, adding the sodium myristate and the sodium silicofluoride, performing injection molding, foaming, vulcanizing and drying to obtain the product.
Further, in this example, the reaction solvent in step 1 is selected from xylene with relatively low polarity, which reduces the speed of nucleophilic substitution reaction and reduces the possibility of byproduct generation.
Further, in this example, as shown in FIG. 1, the three-necked flask reactor described in step 1 and step 2 was composed of a three-necked flask, a thermometer, a stirrer and a condenser, and placed in an oil bath with an ultrasonic reactor having a power of 20 kHz. .
Further, in this example, the reflux reaction described in step 2, using potassium iodide as a catalyst, promoted the reaction by a molar ratio of the amount of 3-bromopropyltriphenylphosphonium salt to the amount of 3-bromopropyltriphenylphosphonium salt (1: 0.01), resulting in a 1-fold increase in the final yield.
In the example, the reflux reaction in step 2 is carried out in a manner that 3-bromopropyltriphenyl phosphonium salt is dissolved in a hot ethanol solvent in advance, and the feeding is dropwise added by a constant pressure funnel for 2 hours, so that the occurrence of side reactions is reduced, and the yield is improved by 25%.
Further in this example, the vulcanization process parameters described in step 4 are: vulcanizing at 120 deg.C for 10min, washing with water, and oven drying at 80 deg.C for 10min to obtain the final product.
The above description is only a preferred mode of the present invention, and it should be noted that, for those skilled in the art, it is possible to make several similar changes and modifications without departing from the principle of the present invention, and these should be considered as being within the protection scope of the textile fabric of the present invention.
Claims (9)
1. A quaternary phosphonium salt type silicone latex characterized in that: the composition comprises the following components in parts by mass: 10-20 parts of quaternary phosphonium salt type organic silicon emulsion, 65-80 parts of latex, 3-6 parts of coupling agent, 2-5 parts of stabilizing agent, 1-3 parts of initiator, 1-3 parts of coagulant and 1-2 parts of foaming agent.
2. The quaternary phosphonium salt-type silicone latex according to claim 1, characterized in that: the composition comprises the following components in parts by mass: 15 parts of quaternary phosphonium salt type organic silicon emulsion, 70 parts of latex, 5 parts of coupling agent, 3 parts of stabilizing agent, 2 parts of initiator, 3 parts of coagulant and 2 parts of foaming agent.
3. A preparation method of quaternary phosphonium salt type organic silicon latex is characterized in that: the method comprises the following steps:
(1) 3-bromopropyl triphenyl phosphonium salt preparation: adding a certain amount of triphenylphosphine, 1, 3-dibromopropane and a reaction solvent into a three-neck flask reactor, wherein the molar ratio of triphenylphosphine to 1, 3-dibromopropane is 1:1, stirring, heating, refluxing and reacting for 8-24 h at 120-140 ℃, cooling, filtering, washing with 50-100 mL of diethyl ether, vacuum drying at 70-85 ℃ to obtain crude 3-bromopropyl triphenyl quaternary phosphonium salt, recrystallizing and purifying, and vacuum drying at 70-85 ℃ for later use;
(2) preparation of organosilicon quaternary phosphonium salt: taking excessive coupling agent KH550, 3-bromopropyltriphenyl quaternary phosphonium salt, an acid-binding agent and a reaction solvent, wherein the molar ratio of the coupling agent KH550, 3-bromopropyltriphenyl quaternary phosphonium salt to the acid-binding agent is 2:1:1, adding the coupling agent KH550, 3-bromopropyltriphenyl quaternary phosphonium salt to the acid-binding agent into a three-neck flask reactor, adding a catalyst, stirring, heating, refluxing and reacting for 4-6 h at the temperature of 60-80 ℃, filtering while the reaction is hot, evaporating the reaction solvent, cooling to room temperature to obtain yellow oily liquid, adding diethyl ether, separating out a white solid, recrystallizing and purifying, washing the diethyl ether for 2-3 times, and performing vacuum drying at the temperature of 70-85 ℃ for later use;
(3) preparation of quaternary phosphonium salt type silicone emulsion: adding organic silicon quaternary phosphonium salt, tween 80, an emulsifier and deionized water into a three-neck flask reactor, stirring and reacting for 0.5-1 h at 40-60 ℃, heating to 80 ℃, adding a certain amount of potassium hydroxide solution, reacting for 3-5 h at constant temperature, cooling, and neutralizing for later use;
(4) preparing quaternary phosphonium salt type organic silicon emulsion graft modified latex: taking a certain amount of latex, a coupling agent and a stabilizing agent, stirring for 15-45 min, heating to 60 ℃, dropwise adding the quaternary phosphonium salt type organic silicon latex into a constant-pressure funnel, dropwise adding for 0.5-1 h, then continuously dropwise adding an initiator, reacting for 4-6 h, adding a foaming agent and a coagulant, performing injection molding, foaming, vulcanizing and drying to obtain the quaternary phosphonium salt type organic silicon latex.
4. The method according to claim 3, wherein the quaternary phosphonium salt silicone latex is prepared by: the reaction solvent in the step (1) is one of toluene, xylene or DMF, and the three-neck flask reactor consists of a three-neck flask, a thermometer, a stirrer and a condenser pipe; in the recrystallization purification process, the solvent is absolute ethyl alcohol.
5. The method for preparing a quaternary phosphonium salt type silicone latex according to claim 1, characterized in that: the reaction solvent in the step (2) is absolute ethyl alcohol, and 3-bromopropyl triphenyl quaternary phosphonium salt is dissolved in a hot ethyl alcohol solvent in advance; the acid-binding agent in the step (2) is one of triethylamine or potassium carbonate; the catalyst in the step (2) is potassium iodide, and the molar ratio of the dosage of the potassium iodide to the dosage of the 3-bromopropyltriphenyl phosphonium salt is 1: 0.01-0.02.
6. The method for producing a quaternary phosphonium salt type silicone latex according to claim 4 or 5, characterized in that: the three-neck flask reactor is placed in an oil bath tank with an ultrasonic reactor, the power of the ultrasonic reactor is 20kHz, and the reflux reaction is carried out under the protection of nitrogen.
7. The method for preparing a quaternary phosphonium salt type silicone latex according to claim 1, characterized in that: in the reflux reaction in the step (2), one of ethanol solutions of the 3-bromopropyltriphenyl quaternary phosphonium salt is added at one time or dropwise in a feeding mode of the 3-bromopropyltriphenyl quaternary phosphonium salt; in the recrystallization purification process in the step (2), the solvent is one or a combination of two of dichloromethane and n-hexane.
8. The method for preparing a quaternary phosphonium salt type silicone latex according to claim 1, characterized in that: the emulsifier in the step (3) is cetyl trimethyl ammonium bromide, so that the interfacial tension between the dispersed phase and the continuous phase is reduced, and the dispersed phase and the continuous phase are easier to emulsify; the mass concentration of the potassium hydroxide solution is 8-15%; the neutralization reaction is to drop glacial acetic acid for neutralization until the pH value is 6-8.
9. The method for preparing a quaternary phosphonium salt type silicone latex according to claim 1, characterized in that: the latex in the step (4) is one or the combination of two of natural latex and synthetic latex; the coupling agent in the step (4) is vinyl trimethylsilane; the stabilizer is sodium bisulfite, which can enhance the surface charge, protective layer and hydration degree of the latex particles; the initiator is ammonium persulfate; the foaming agent is one of lauric acid, sodium palmitate and sodium myristate; the coagulant is a delayed coagulant, namely sodium silicofluoride, so that the latex is slowly gelled; the vulcanization process parameters are as follows: the vulcanizing temperature is 100-130 ℃, the vulcanizing time is 5-15 min, and the vulcanizing temperature is 70-100 ℃, the drying time is 10-25 min.
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| CN113799514A (en) * | 2021-09-24 | 2021-12-17 | 广州松源实业有限公司 | Environment-friendly paper file box with mould-proof and insect-proof functions |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113799514A (en) * | 2021-09-24 | 2021-12-17 | 广州松源实业有限公司 | Environment-friendly paper file box with mould-proof and insect-proof functions |
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