阅读说明：本技术 一种工程防水用氯丁胶乳的制备方法 (Preparation method of neoprene latex for engineering waterproofing ) 是由 叶伟 戴祖宏 曾维亮 于凯华 于 2019-10-31 设计创作，主要内容包括：本发明涉及氯丁胶乳技术领域,具体公开了一种工程防水用氯丁胶乳的制备方法,包括以下步骤：称量氯化铝粉末,加水搅拌至溶解；在水相配制槽内加入水,在搅拌作用下依次加入氢氧化钠、盐类和乳化剂得水相,将氯化铝溶液与水相混合；将氯丁二烯送入油相配制槽内,加入调节剂,搅拌使调节剂溶解；在配制槽内加入水,乳化剂和碳酸钠,搅拌溶解得甲液,在配制槽内加入软水,加入防老剂和吩噻嗪,搅拌溶解得乙液,将甲液和乙液混合乳化30～45min得终止剂；聚合釜中先加入油相,后加入水相,搅拌乳化,加入引发剂开始聚合,当总固物合格后,放入终止釜深转,后加入终止剂,搅拌30～35min制得成品胶乳；采用本发明的制备方法可制得稳定性高、防水性能良好的阳离子氯丁胶乳。(The invention relates to the technical field of neoprene latex, and particularly discloses a preparation method of neoprene latex for engineering waterproofing, which comprises the following steps: weighing aluminum chloride powder, adding water and stirring until the aluminum chloride powder is dissolved; adding water into a water phase preparation tank, sequentially adding sodium hydroxide, salts and an emulsifier under the stirring action to obtain a water phase, and mixing an aluminum chloride solution with the water phase; feeding chloroprene into an oil phase preparation tank, adding a regulator, and stirring to dissolve the regulator; adding water, an emulsifier and sodium carbonate into a preparation tank, stirring and dissolving to obtain a first solution, adding soft water into the preparation tank, adding an anti-aging agent and phenothiazine, stirring and dissolving to obtain a second solution, and mixing and emulsifying the first solution and the second solution for 30-45 min to obtain a terminator; adding an oil phase into a polymerization kettle, adding a water phase, stirring and emulsifying, adding an initiator to start polymerization, putting the polymerization kettle into a termination kettle to perform deep rotation after the total solids are qualified, adding a terminator, and stirring for 30-35 min to obtain a finished latex; the cationic neoprene latex with high stability and good waterproof performance can be prepared by adopting the preparation method.)

1. A preparation method of neoprene latex for engineering waterproofing is characterized in that: the method comprises the following steps:

step 1, preparing an aluminum chloride solution: weighing aluminum chloride powder, adding water and stirring to completely dissolve the aluminum chloride;

step 2, preparing a water phase: adding water into a water phase preparation tank, sequentially adding sodium hydroxide, salts and an emulsifier under the stirring action to obtain a water phase, and mixing the aluminum chloride solution prepared in the step 1 with the water phase;

step 3, preparing an oil phase: feeding chloroprene into an oil phase preparation tank, adjusting the temperature, adding a regulator, and stirring to dissolve the regulator;

step 4, preparing a terminator: adding water into a preparation tank, heating to 40-45 ℃, adding an emulsifier and sodium carbonate, stirring and dissolving to obtain a first solution, adding soft water into the preparation tank, heating to 75-85 ℃, adding an anti-aging agent and phenothiazine, stirring and dissolving to obtain a second solution, mixing and emulsifying the first solution and the second solution for 30-45 min to obtain a terminator, wherein the emulsifying temperature is 75-80 ℃;

step 5 polymerization: and (3) adding the oil phase prepared in the step (2) into a polymerization kettle, adding the water phase prepared in the step (1), stirring and emulsifying for 20-25 min, wherein the emulsifying temperature is 34-38 ℃, adding an initiator to start polymerization, putting the polymerization kettle into a stopping kettle to perform deep rotation for 8-9 h when the total solid content is more than 49%, wherein the deep rotation temperature is 40-50 ℃, adding the stopping agent prepared in the step (3), and stirring for 30-35 min to obtain the finished product of the latex.

2. The method for preparing the neoprene latex for engineering waterproofing according to claim 1, wherein the neoprene latex for engineering waterproofing comprises the following steps: the water added in the steps 1-4 is soft water without calcium and magnesium.

3. The preparation method of the neoprene latex for engineering waterproofing according to claim 2, wherein: and (3) after the aluminum chloride solution is completely dissolved into the water phase in the step (2), introducing steam, and heating the water phase to 45-55 ℃.

4. The method for preparing the neoprene latex for engineering waterproofing according to claim 3, wherein the neoprene latex for engineering waterproofing comprises the following steps: and the emulsifier adopted in the step 2 and the step 4 is dodecyl trimethyl ammonium chloride or dodecyl trimethyl ammonium bromide.

5. The method for preparing the neoprene latex for engineering waterproofing according to claim 4, wherein the neoprene latex for engineering waterproofing comprises the following steps: chloroprene is pumped by nitrogen in the step 3.

6. The method for preparing the neoprene latex for engineering waterproofing according to claim 5, wherein the neoprene latex for engineering waterproofing comprises the following steps: the regulator adopted in the step 3 is diisopropyl xanthate and sulfur.

7. The method for preparing the neoprene latex for engineering waterproofing according to claim 6, wherein the neoprene latex for engineering waterproofing comprises the following steps: the anti-aging agent adopted in the step 4 is 2, 6-di-tert-butyl-4-methylphenol, n-octadecyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate or pentaerythritol tetra- [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ].

8. The method for preparing the neoprene latex for engineering waterproofing according to claim 7, wherein: the initiator adopted in the step 5 is hydrogen peroxide.

9. The method for preparing the neoprene latex for engineering waterproofing according to claim 8, wherein: and (3) standing the finished latex prepared in the step (5) for more than 30min, filtering and packaging.

10. The method for preparing the neoprene latex for engineering waterproofing according to claim 9, wherein: and (4) storing the finished product latex prepared in the step (5) at the temperature of 25-30 ℃.

Technical Field

The invention relates to the technical field of neoprene latex, in particular to a preparation method of neoprene latex for engineering waterproofing.

Background

Polychloroprene latexes are produced by polymerizing chloroprene in an emulsion. The neoprene latex can produce a plurality of varieties with different characteristics and purposes to meet the requirements of different products due to different adopted emulsifiers, initiators, regulators, terminators, auxiliary monomers and polymerization conditions. Polychloroprene latexes can be broadly classified into two broad categories, negative latexes and positive latexes. The domestic neoprene latex has general purpose neoprene latex suitable for manufacturing industrial gloves and other dipped products, concentrated neoprene latex suitable for manufacturing sponge products and cold-resistant neoprene latex which can be used for manufacturing weather balloons and products with low temperature characteristic requirements. These latexes are all negative latexes.

The neoprene latex is applied to adhesives, is mostly anionic latex, and is suitable for bonding paper, cotton cloth, fiber, leather and wood. Is not suitable for engineering waterproof materials. The latex particles of the anionic neoprene latex are provided with negative electric nuclei, and are favorable for being bonded with adherends (such as paper, cotton cloth, fiber, leather, wood and the like) with positive electric nuclei. Engineering materials such as cement, glass and materials with high valence metal ions have the same surface charge as anionic latex particles due to negative charge nuclei on the surface, and have poor adsorption. Therefore, anionic latexes are not suitable for engineering waterproofing materials.

Based on the problems, I have developed a preparation method of cationic neoprene latex for engineering waterproofing, which can prepare cationic neoprene latex with good stability and good waterproofness.

Disclosure of Invention

The invention provides a preparation method of neoprene latex with good stability and engineering water resistance.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a preparation method of engineering waterproof neoprene latex comprises the following steps:

step 1, preparing an aluminum chloride solution: weighing aluminum chloride powder, adding water and stirring to completely dissolve the aluminum chloride;

step 2, preparing a water phase: adding water into a water phase preparation tank, sequentially adding sodium hydroxide, salts and an emulsifier under the stirring action to obtain a water phase, and mixing the aluminum chloride solution prepared in the step 1 with the water phase;

step 3, preparing an oil phase: feeding chloroprene into an oil phase preparation tank, adjusting the temperature, adding a regulator, and stirring to dissolve the regulator;

step 4, preparing a terminator: adding water into a preparation tank, heating to 40-45 ℃, adding an emulsifier and sodium carbonate, stirring and dissolving to obtain a first solution, adding soft water into the preparation tank, heating to 75-85 ℃, adding an anti-aging agent and phenothiazine, stirring and dissolving to obtain a second solution, mixing and emulsifying the first solution and the second solution for 30-45 min to obtain a terminator, wherein the emulsifying temperature is 75-80 ℃;

step 5 polymerization: and (3) adding the oil phase prepared in the step (2) into a polymerization kettle, adding the water phase prepared in the step (1), stirring and emulsifying for 20-25 min, wherein the emulsifying temperature is 34-38 ℃, adding an initiator to start polymerization, putting the polymerization kettle into a stopping kettle to perform deep rotation for 8-9 h when the total solid content is more than 49%, wherein the deep rotation temperature is 40-50 ℃, adding the stopping agent prepared in the step (3), and stirring for 30-35 min to obtain the finished product of the latex.

The technical principle and the effect of the technical scheme are as follows:

1. the neoprene latex prepared by the method has high stability, does not generate the phenomenon of gel in the process of preparing the adhesive for engineering, and simultaneously has good waterproof effect.

2. In the scheme, part of aluminum chloride reacts with sodium hydroxide in a water phase to form floccule of the aluminum hydroxide, the floccule can protect latex, and the aluminum chloride can be ionized in a system of the latex and also plays a role of an electrolyte.

Further, the water added in the steps 1-4 is soft water without calcium and magnesium.

Has the advantages that: the adoption of soft water can avoid unnecessary calcium and magnesium impurities introduced in the preparation and polymerization processes, thereby influencing the quality of the latex.

Further, after the aluminum chloride solution is completely dissolved into the water phase in the step 2, introducing steam, and heating the water phase to 45-55 ℃.

Has the advantages that: before emulsification, the temperature of the water phase is raised, so that the temperature of the emulsion after emulsification with the oil phase can enable the initiator to generate free radicals to initiate polymerization reaction.

Further, the emulsifier used in step 2 and step 4 is dodecyl trimethyl ammonium chloride or dodecyl trimethyl ammonium bromide.

Has the advantages that: the emulsifier adopts dodecyl trimethyl ammonium chloride or dodecyl trimethyl ammonium bromide to enable latex particles to carry positive charges, so that the cation neoprene latex with high stability is prepared.

Further, chloroprene is fed under pressure with nitrogen in step 3.

Has the advantages that: the chloroprene fed under pressure by using nitrogen can isolate the adverse effect of oxygen in the air on the latex.

Further, the regulators adopted in the step 3 are diisopropyl xanthate and sulfur.

Has the advantages that: diisopropyl xanthate and sulfur as regulators enable polymers with a molecular weight range that meets the requirements.

Further, the anti-aging agent adopted in the step 4 is 2, 6-di-tert-butyl-4-methylphenol, n-octadecyl beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate or pentaerythritol tetrakis [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ].

Has the advantages that: the three anti-aging agents can achieve good anti-aging effect.

Further, the initiator used in the step 5 is hydrogen peroxide.

Has the advantages that: when hydrogen peroxide is used as an initiator, peroxy groups (-O-) contained in hydrogen peroxide are heated to break the-O-bond and split into two corresponding free radicals HO^.Thereby initiating polymerization of the chloroprene monomer.

Further, the finished latex prepared in the step 5 is stood for more than 30min, filtered and packaged.

Has the advantages that: in order to ensure the quality of the final latex, the gel that may be present during the preparation is filtered.

Further, the finished latex prepared in the step 5 is stored at a temperature of 25-30 ℃.

Has the advantages that: the storage at the temperature of 25-30 ℃ can ensure the quality of the finished latex and prevent the adverse effect of over-high and over-low temperature on the finished latex.

Detailed Description

The following is further detailed by way of specific embodiments: