阅读说明：本技术 氯乙烯聚合终止剂、其制备方法及应用 (Vinyl chloride polymerization terminator, preparation method and application thereof ) 是由 王晶 刘浩 张磊 张新华 裴小静 *** 李静 刘容德 王晓敏 高磊 于 2018-07-25 设计创作，主要内容包括：本发明属于树脂合成领域,具体涉及一种氯乙烯聚合终止剂、其制备方法及应用。包括以下重量份数的原料：二乙基羟胺10～20份、季戊四醇四(3-月桂基硫代丙酸酯)30～40份、十八烷基-3-(3,5-二叔丁基-4-羟苯基)丙酸酯10～20份、去离子水50～60份、分散剂1～3份和乳化剂0.1～0.5份。本发明各组分具有协同增效作用,既能够起到良好的氯乙烯聚合终止效果,又能够有效地提高树脂的老化白度,具有终止效率高、PVC树脂的白度高、PVC透明制品黄色指数低的优点。本发明还提供其制备方法,确保复合终止剂乳液在计量加入时各批次间稳定均匀,在工艺管线内流动性良好。(The invention belongs to the field of resin synthesis, and particularly relates to a vinyl chloride polymerization terminator, and a preparation method and application thereof. The composite material comprises the following raw materials in parts by weight: 10-20 parts of diethylhydroxylamine, 30-40 parts of pentaerythritol tetrakis (3-laurylthiopropionate), 10-20 parts of octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, 50-60 parts of deionized water, 1-3 parts of a dispersant and 0.1-0.5 part of an emulsifier. The components of the invention have synergistic interaction effect, can play a good role in terminating vinyl chloride polymerization, can effectively improve the aging whiteness of resin, and has the advantages of high terminating efficiency, high whiteness of PVC resin and low yellow index of PVC transparent products. The invention also provides a preparation method of the composite terminator emulsion, which ensures that the composite terminator emulsion is stable and uniform among batches when being metered and added and has good fluidity in a process pipeline.)

1. A terminator for vinyl chloride polymerization, characterized in that: the composite material comprises the following raw materials in parts by weight: 10-20 parts of diethylhydroxylamine, 30-40 parts of pentaerythritol tetrakis (3-laurylthiopropionate), 10-20 parts of octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, 50-60 parts of deionized water, 1-3 parts of a dispersant and 0.1-0.5 part of an emulsifier.

2. A vinyl chloride polymerization terminator according to claim 1, characterized in that: the dispersing agent is a polyvinyl alcohol aqueous solution with the polymerization degree of 300-400, the alcoholysis degree of 60-80% and the concentration of 4-6%.

3. A vinyl chloride polymerization terminator according to claim 1, characterized in that: the emulsifier is one or more of sodium dodecyl benzene sulfonate, sodium dodecyl sulfate, polyoxyethylene sorbitan monooleate, sorbitan trioleate and polyoxyethylene sorbitan monolaurate.

4. A vinyl chloride polymerization terminator according to claim 3, characterized in that: the emulsifier is sorbitan trioleate.

5. A method for preparing a terminator for vinyl chloride polymerization according to any one of claims 1 to 4, characterized in that: the method comprises the following steps: pentaerythritol tetra (3-lauryl thiopropionate), octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate and deionized water are mixed, stirred and heated to 50-55 ℃, kept for 10-15 minutes, cooled to room temperature of 23 +/-2 ℃, then added with diethylhydroxylamine, a dispersant and an emulsifier, stirred uniformly and poured into a high-speed shearing emulsifying machine to be emulsified for 20-40 min at the rotating speed of 1800-2600 r/min, and then the vinyl chloride polymerization terminator is obtained.

6. Use of a vinyl chloride polymerization terminator as set forth in any one of claims 1 to 4, characterized in that: adding desalted water, a polyvinyl alcohol 424H aqueous solution with the concentration of 5%, a hydroxypropyl methyl cellulose E50 aqueous solution with the concentration of 3%, tert-butyl peroxyneodecanoate and tert-amyl peroxypivalate into a reaction kettle, pumping the pressure in the kettle to be lower than-0.09 MPa, adding a vinyl chloride monomer, starting stirring, stirring and mixing at normal temperature, heating, reacting, and adding the vinyl chloride polymerization terminator into the kettle when the pressure in the kettle is reduced by 0.25-0.35 MPa.

7. Use according to claim 6, characterized in that: the reaction kettle is a 5L stainless steel pressure reaction kettle provided with two layers of double-blade flat slurry.

8. Use according to claim 6, characterized in that: adding vinyl chloride monomer, starting stirring, controlling the rotating speed at 450-480 rpm, stirring and mixing for 10-15 min at normal temperature, then heating to 58.0 +/-0.2 ℃, starting reaction timing after the temperature is stabilized, and filling the vinyl chloride polymerization terminator into the kettle when the pressure in the kettle is reduced by 0.25-0.35 MPa.

9. Use according to claim 6, characterized in that: adding 1.8-2.4 kg of desalted water, 8-10 g of a 5% polyvinyl alcohol 424H aqueous solution, 6-6.67 g of a 3% hydroxypropyl methyl cellulose E50 aqueous solution, 0.255-0.267 g of 75% tert-butyl peroxyneodecanoate and 0.500-0.533 g of 75% tert-amyl peroxypivalate into a reaction kettle, pumping the pressure in the kettle to be lower than-0.09 MPa, adding 1kg of vinyl chloride monomer, starting stirring at the rotating speed of 440-470 rpm, stirring and mixing at normal temperature for 10-15 min, raising the temperature of the kettle to 58.0 +/-0.2 ℃, starting reaction timing after the temperature is stabilized, and adding the vinyl chloride polymerization terminator into the kettle when the pressure in the kettle is reduced by 0.25-0.35 MPa.

10. Use according to claim 9, characterized in that: the addition amount of the vinyl chloride polymerization terminator is 400-700 ppm based on the weight of vinyl chloride.

Technical Field

The invention belongs to the field of resin synthesis, and particularly relates to a vinyl chloride polymerization terminator, and a preparation method and application thereof.

Background

The terminating agent stops or significantly reduces the reaction rate by combining with residual initiator reactive radicals and residual initiator to form inactive compounds, which effectively protects the polymer from damage by thermal oxygen aging during stripping and subsequent processing. The terminator is added when the polymerization reaction reaches a set end point, and commonly used terminators are bisphenol A, thiosemicarbazone, BHT, and the like. A single terminator often cannot meet the requirements of efficiently terminating the polymerization reaction and improving the thermal stability of the resin at the same time, and the terminator is developing towards the functional compound direction of both chain termination and improving the thermal stability of PVC.

CN201110380532 discloses a preparation method and a use method of a polyvinyl chloride resin terminator, wherein the terminator is an oil-soluble composite liquid terminator and is mainly compounded by HKY-10, a benzofuranone antioxidant and a phosphite antioxidant. Wherein HKY-10 is a liquid antioxidant prepared by dissolving 2, 6-di-tert-butyl-4- (1-phenylethyl) phenol in an organic solvent. The aging whiteness of the PVC resin product can be improved by using the terminator. The formula used is different from the patent of the invention. The terminator of the invention introduces an organic solvent, and can potentially influence the production and polymerization of PVC.

CN103435725A discloses an aqueous emulsion type polyvinyl chloride resin terminator and a preparation method thereof, wherein the terminator comprises, by weight, 70-140 parts of a stabilizer, 18-42 parts of a phenol antioxidant, 0.1-0.3 part of a light stabilizer, 4-18 parts of a polymerization inhibitor, 13-96 parts of an emulsifier, 1-8 parts of a dispersant, and 100-320 parts of water, the stabilizer and the phenol antioxidant are placed in a stirrer to be heated and dissolved, the temperature is reduced to normal temperature after heat preservation, then the light stabilizer and the polymerization inhibitor are added, and the mixture is stirred uniformly to obtain a mixed terminator solution. And adding an emulsifier into the mixed terminator solution, heating to 40-60 ℃, uniformly stirring, and mixing the emulsion. And simultaneously mixing the dispersing agent and water, stirring and heating to 80-100 ℃ to obtain a dispersing solution. And finally, adding the dispersion solution into the mixed emulsion to obtain the aqueous emulsion type polyvinyl chloride terminator, which can well improve the thermal stability and processability of the PVC resin. The used formula is different from the patent of the invention, and the phenolic antioxidant used in the invention is toxic.

CN201610153540 discloses a PVC oil-soluble terminator and a preparation method thereof, which comprises the following raw materials in parts by weight: epoxidized soybean oil: 5-50 parts of an antioxidant: 10-30 parts of bisphenol A: 10-40 parts of a solid terminator: 1-20 parts of a stabilizer: 5-40 parts of a plasticizer: 1-40 parts of styrene: 5-45 parts of solvent oil: 5-25 parts of methanol solution: 5-40 parts. The PVC resin oil-soluble terminator obtained by the invention has good termination effect and long thermal stability time, and the solid material is added into the reaction vessel at one time during preparation, so that the reaction time is greatly shortened, the reaction temperature is lower, the energy consumption is reduced, and the production capacity of a production device is improved. The formula and the process used by the invention are different from the patent of the invention, and the oil-soluble terminator contains bisphenol A with higher toxicity, which runs counter to the development direction of green environmental protection of the terminator.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a vinyl chloride polymerization terminator, which can achieve good vinyl chloride polymerization termination effect, can effectively improve the aging whiteness of resin, and has the advantages of high termination efficiency, high whiteness of PVC resin and low yellow index of a PVC transparent product; the invention also provides a preparation method and application thereof.

The vinyl chloride polymerization terminator disclosed by the invention comprises the following raw materials in parts by weight: 10-20 parts of diethylhydroxylamine, 30-40 parts of pentaerythritol tetrakis (3-laurylthiopropionate), 10-20 parts of octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, 50-60 parts of deionized water, 1-3 parts of a dispersant and 0.1-0.5 part of an emulsifier.

The dispersing agent is a polyvinyl alcohol aqueous solution with polymerization degree of 300-400, alcoholysis degree of 60-80% and concentration of 4-6%, and the concentration is preferably 5%.

The emulsifier is one or more of sodium dodecyl benzene sulfonate, sodium dodecyl sulfate, polyoxyethylene sorbitan monooleate, sorbitan trioleate and polyoxyethylene sorbitan monolaurate. Sorbitan trioleate is preferred.

The preparation method of the vinyl chloride polymerization terminator comprises the following steps: pentaerythritol tetra (3-lauryl thiopropionate), octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate and deionized water are mixed, stirred and heated to 50-55 ℃, kept for 10-15 minutes, cooled to room temperature of 23 +/-2 ℃, then added with diethylhydroxylamine, a dispersant and an emulsifier, stirred uniformly and poured into a high-speed shearing emulsifying machine to be emulsified for 20-40 min at the rotating speed of 1800-2600 r/min, and then the vinyl chloride polymerization terminator is obtained.

The application of the vinyl chloride polymerization terminator disclosed by the invention comprises the steps of adding desalted water, a polyvinyl alcohol 424H aqueous solution with the concentration of 5%, a hydroxypropyl methyl cellulose E50 aqueous solution with the concentration of 3%, tert-butyl peroxyneodecanoate and tert-amyl peroxypivalate into a reaction kettle, pumping the pressure in the kettle to be lower than-0.09 MPa, adding a vinyl chloride monomer, starting stirring, stirring and mixing at normal temperature, then heating for reaction, and adding the vinyl chloride polymerization terminator into the kettle when the pressure in the kettle is reduced by 0.25-0.35 MPa.

Preferably, the reaction kettle is a 5L stainless steel pressure reaction kettle provided with two layers of double-blade flat slurry.

Preferably, vinyl chloride monomer is added, stirring is started, the rotating speed is controlled to be 450-480 rpm, stirring and mixing are carried out for 10-15 min at normal temperature, then the temperature is raised to 58.0 +/-0.2 ℃, the reaction is started for timing after the temperature is stabilized, and when the pressure in the kettle is reduced by 0.25-0.35 MPa, the vinyl chloride polymerization terminator is added into the kettle.

As a preferable technical scheme, the application of the vinyl chloride polymerization terminator provided by the invention comprises the steps of adding 1.8-2.4 kg of desalted water, 8-10 g of a 5% polyvinyl alcohol 424H aqueous solution, 6-6.67 g of a 3% hydroxypropyl methyl cellulose E50 aqueous solution, 0.255-0.267 g of 75% tert-butyl peroxyneodecanoate and 0.500-0.533 g of 75% tert-amyl peroxypivalate into a reaction kettle, pumping the pressure in the kettle to be lower than-0.09 MPa, adding 1kg of vinyl chloride monomer, starting stirring at a rotating speed of 440-470 rpm, stirring and mixing at normal temperature for 10-15 min, raising the temperature of the kettle to 58.0 +/-0.2 ℃, starting reaction timing after the temperature is stabilized, and adding the vinyl chloride polymerization terminator into the kettle when the pressure in the kettle is reduced by 0.25-0.35 MPa.

The addition amount of the vinyl chloride polymerization terminator is 400-700 ppm based on the weight of vinyl chloride.

Compared with the prior art, the invention has the following advantages:

(1) the invention adopts diethylhydroxylamine, pentaerythritol tetra (3-lauryl thiopropionate), octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, a dispersant and an emulsifier, and the components have synergistic effect, thereby not only playing a good vinyl chloride polymerization termination effect, but also effectively improving the aging whiteness of the resin, and having the advantages of high termination efficiency, high whiteness of PVC resin and low yellow index of PVC transparent products.

(2) The invention also provides a preparation method thereof, which obtains the composite terminator emulsion with stably and uniformly dispersed components of the terminator by heating, adding the emulsifier and the dispersant which are suitable for the emulsification of the terminator and shearing the emulsion at a high speed by a shearing emulsifying machine, ensures that the composite terminator emulsion is stable and uniform among batches when being metered and added, and has good fluidity in a process pipeline.

Detailed Description

The present invention will be further described with reference to the following examples.