KR20180039520A - Vinyl chloride polymer latex and preparation method thereof - Google Patents

Abstract

The present invention relates to a vinyl chloride polymer latex having a foam inhibiting effect and to a manufacturing method thereof. The vinyl chloride polymer latex has the foam inhibiting effect by containing a specific amount of a de-foaming agent in the form of vegetable oil and can remarkably reduce the foam generation in the production of a molded article using the de-foaming agent.

Description

TECHNICAL FIELD [0001] The present invention relates to a vinyl chloride polymer latex and a vinyl chloride polymer latex,

TECHNICAL FIELD The present invention relates to a vinyl chloride-based polymer latex having an effect of suppressing foaming and a method for producing the latex.

The vinyl chloride resin is a resin containing 50% or more of vinyl chloride. It is inexpensive, hardness is easy to control, and can be applied to most processing equipments. In addition, it can provide molded articles having excellent physical and chemical properties such as mechanical strength, weather resistance, and chemical resistance, and is widely used in various fields.

Such a vinyl chloride resin is molded into a product by extrusion, calendering, injection molding, paste molding, etc. after mixing various additives such as a plasticizer, a colorant and a heat stabilizer. Particularly, in the case of paste processing using a mixture with a plasticizer, it is molded into various applications in various fields such as building materials, toys, artificial leather, shoes, and gloves according to the processing method.

The pasting is generally performed by spray drying a paste-working vinyl chloride polymer latex obtained by emulsion polymerization to form final resin particles, and the particles are dispersed in a solvent or a plasticizer to form a reverse roll-coating knife coatings, screen coatings, spray coatings, gravure and csreen printing, rotocation casting, shell casting and dipping, to produce flooring, wallpaper, tarpaulin, Gloves, automotive underbody coatings, sealants and carpet tiles.

Such a vinyl chloride polymer for paste processing is usually processed and used in the form of a plastisol composed of various additives such as heat stabilizers together with a plasticizer. When bubbles are present in the plastisol at the time of processing, Mechanical properties (for example, tensile strength and the like) may be lowered, or in the case of a molded article requiring transparency, problems may occur in appearance. Accordingly, a defoaming process for removing bubbles in the plastisol before processing is essentially required.

In addition, in the production of the vinyl chloride type polymer latex through emulsion polymerization, a rapid temperature rise occurs due to the cage effect of the late polymerization initiator in the polymerization reaction, and the stability of the vinyl chloride type polymer latex produced thereby deteriorates There arises a problem that the process stability is lowered due to an increase in pressure inside the reactor.

Accordingly, there is a need to develop a vinyl chloride-based polymer latex which is excellent in stability and can be easily applied to paste processing.

JP 2003-516301 A

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the prior art, and it is an object of the present invention to provide a vinyl chloride type polymer latex having an effect of suppressing foaming.

Another object of the present invention is to provide a process for producing the vinyl chloride-based polymer latex.

In order to solve the above-mentioned problems, the present invention provides a rubber composition comprising 100 parts by weight of a vinyl chloride polymer; And 0.02 part by weight to 0.05 part by weight of a vegetable oil-based antifoaming agent based on 100 parts by weight of the polymer, wherein the vegetable oil-based defoaming agent comprises a silicon-based mixture containing silicon particles and siloxane particles do.

Also, the present invention includes a step (A) of mixing and polymerizing 100 parts by weight of a vinyl chloride monomer and 0.02 to 0.05 parts by weight of a vegetable oil defoaming agent, wherein the vegetable oil defoaming agent comprises a silicon mixture, Wherein the silicon-based mixture comprises silicon particles and siloxane particles.

The vinyl chloride-based polymer latex according to the present invention has a foam inhibiting effect by containing a vegetable oil-based defoaming agent in a specific amount, and foam production can be suppressed during the production of a molded article using the same, so that a separate defoaming step is not necessary And the process efficiency can be improved.

The process for producing the vinyl chloride polymer latex according to the present invention can provide excellent reaction stability by introducing the vegetable oil defoaming agent at a specific polymerization conversion time point, and consequently, a vinyl chloride polymer latex having excellent stability can be produced.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments of the invention and, together with the description of the invention, It should not be construed as limited.
1 is a graph showing changes in dispersibility with time of the defoamer dispersion used in Example 1, Comparative Example 3 and Comparative Example 4 according to an embodiment of the present invention. After cessation of minute, c) was observed after 100 min.

Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.

The terms and words used in the present specification and claims should not be construed in an ordinary or dictionary sense and the inventor can properly define the concept of the term to describe its invention in the best possible way It should be construed as meaning and concept consistent with the technical idea of the present invention.

The present invention provides a vinyl chloride polymer latex having excellent stability and little foaming.

The vinyl chloride-based polymer latex according to an embodiment of the present invention comprises 100 parts by weight of vinyl chloride-based monomer-derived units; And 0.02 part by weight to 0.05 part by weight of a vegetable oil defoaming agent based on 100 parts by weight of the derived unit, wherein the vegetable oil defoaming agent comprises a silicon-based mixture containing silicon particles and siloxane particles.

If the vegetable oil defoaming agent is contained in a smaller amount than the above range, the effect of suppressing foaming may be insignificant or not. If the defoaming agent is contained in an amount exceeding the above range, But the viscosity of the plastisol containing the vinyl chloride type polymer latex containing the latex is increased and the flowability is deteriorated to lower the molding processability and consequently the physical properties such as the appearance characteristics of the produced molded article are deteriorated May occur.

As used herein, the term "siloxane" refers to a compound comprising Si-O bonds and consisting of silicon, oxygen and hydrogen.

The vinyl chloride-based polymer latex according to an embodiment of the present invention may include a vinyl chloride-based monomer-derived unit and a vegetable oil-based defoaming agent as described above, wherein the vegetable oil-based defoaming agent comprises a vinyl chloride- And 0.02 part by weight to 0.05 part by weight based on 100 parts by weight of the composition.

Specifically, the vegetable oil-based antifoaming agent may be one comprising an oil component obtained from a plant and containing rapeseed oil, and may include a silicon mixture including silicon particles and siloxane particles as some components. That is, the vegetable oil defoaming agent may be a seed oil containing silicon particles and siloxane particles. At this time, the vegetable oil defoaming agent may include 1 to 10% by weight of the silicon-based mixture, and specifically 3 to 7% by weight. If the vegetable oil defoamer contains a silicon-based mixture in excess of the above-mentioned range, pinholes or the like may be formed on the surface of the molded article, resulting in deterioration in appearance characteristics.

In addition, the silicon particles and the siloxane particles may independently have an average particle diameter (D ₅₀ ) of 1 μm to 2 μm.

Generally, the defoamer used in the polymer is diluted with water to a certain concentration and is used. When the dispersibility to water is poor, a large amount of defoamer is required for achieving the objective, and storage stability is not easy. . Therefore, it is necessary that the defoaming agent exhibits excellent dispersibility with respect to water in order to obtain a desired foaming inhibiting effect without affecting other physical properties of the polymer.

The vegetable oil defoaming agent according to an embodiment of the present invention includes a silicon mixture including silicon particles and siloxane particles, wherein each of the silicon particles and the siloxane particles has an average particle size as described above, Can be excellent.

Specifically, the average particle size was measured using a particle size analyzer (Nanotrac 150, Microtrac). Specifically, the silicon particles and the siloxane particles to be measured for the average particle diameter were each diluted to 0.1 wt% in deionized water, And then measured using the particle size analyzer.

Therefore, the vinyl chloride-based polymer latex according to an embodiment of the present invention may contain a vegetable oil-based defoaming agent in a specific amount, thereby having excellent latex stability and foam suppressing effect. Therefore, a defoaming process is not required in the production of a molded article using the plastisol containing the foam, and the defoaming process time can be reduced, and deterioration of physical properties due to foam can be suppressed.

On the other hand, the unit derived from the vinyl chloride monomer may be a polymer originating from a vinyl chloride monomer, a vinyl chloride monomer itself, or a state in which the polymer and the monomer are mixed.

The vinyl chloride monomer may be a mixture of a vinyl chloride monomer or a vinyl chloride monomer and a vinyl monomer having a copolymerization with the vinyl chloride monomer, and the vinyl chloride monomer may be a mixture of a vinyl chloride monomer and a vinyl monomer The vinyl chloride polymer may be used by adjusting the vinyl chloride content of the prepared vinyl chloride polymer to 50 wt% or more.

Examples of the vinyl monomer include, but are not limited to, olefin compounds such as ethylene, propylene and butyne; Vinyl esters such as vinyl acetate, vinyl propionate and vinyl stearate; Unsaturated nitriles such as acrylonitrile; Vinyl alkyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl octyl ether and vinyl lauryl ether; Vinylidene halides such as vinylidene chloride; Unsaturated fatty acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, maleic anhydride, itaconic anhydride, and anhydrides of these fatty acids; Unsaturated fatty acid esters such as methyl acrylate, ethyl acrylate, monomethyl maleate, dimethyl maleate, and butyl benzyl maleate; Diallyl phthalate, and the like. These vinyl monomers may be used singly or in combination of two or more.

Specifically, the vinyl monomer may be vinyl acetate.

Further, the present invention provides a process for producing the vinyl chloride-based polymer latex.

The manufacturing method according to an embodiment of the present invention includes a step of mixing and polymerizing 100 parts by weight of a vinyl chloride monomer and 0.02 to 0.05 parts by weight of a vegetable oil defoaming agent (step A), and the vegetable oil defoaming agent Silicon mixture, wherein the silicon-based mixture comprises silicon particles and siloxane particles.

Here, the vegetable oil defoaming agent may include 1 to 10% by weight of the silicon-based mixture, and more specifically 3 to 7% by weight of the silicon-based mixture.

The vinyl chloride monomer used in the production method according to an embodiment of the present invention may be a vinyl chloride monomer alone, or a mixture of a vinyl chloride monomer and a vinyl monomer copolymerizable with the vinyl chloride monomer, and the specific vinyl monomer may be a tact As shown in FIG.

The step A may be carried out by mixing and polymerizing a vinyl chloride monomer and a vegetable oil defoaming agent, and the vegetable oil defoaming agent may be added to the vinyl chloride monomer 100 0.02 part by weight to 0.05 part by weight based on the weight of the composition. Herein, the vegetable oil defoaming agent includes a silicon mixture including silicon particles and siloxane particles, and is specifically as described above. If the vegetable oil defoaming agent is added in an amount less than the above range, the amount of the vegetable oil defoaming agent contained in the prepared vinyl chloride type polymer latex is too small, And the amount of the vegetable oil-based defoaming agent in the produced vinyl chloride-based polymer latex may be excessive in the case of adding the vegetable oil-based defoaming agent in an amount exceeding the above range , Resulting in a problem that the physical properties, for example, the appearance characteristics, of the molded article produced using the same are deteriorated.

The vegetable oil defoaming agent may be added to the vinyl chloride monomer at a specific point in time after the initiation of polymerization. For example, the vegetable oil defoaming agent may be added at a polymerization conversion rate of 5% to 90%. Specifically, the vegetable oil-based antifoaming agent may be added at a time when the polymerization conversion rate is 5% to 20% after polymerization initiation or when the polymerization conversion rate is 70% to 90%. More specifically, the vegetable oil- May be added at a point of time of polymerization conversion of 80% to 90% after initiation of polymerization. The production method according to an embodiment of the present invention can improve the reaction stability by suppressing the rapid temperature rise at the end of the polymerization reaction by adding the vegetable oil defoaming agent at a specific time and participating in the polymerization reaction, This excellent vinyl chloride-based polymer latex can be produced. In this case, the vegetable oil defoaming agent may be added all at once or all at once in a specific ratio, or may be added continuously in the range of the polymerization conversion time point described above.

The term " polymerization conversion ratio "used in the present invention indicates the degree of conversion of a vinyl chloride monomer into a polymer, which may be measured using a butane tracer equipped with gas chromatography. Specifically, a polymerization conversion curve according to the ratio of vinyl chloride monomer to butane over time was prepared at each polymerization condition under a certain polymerization condition, and polymerization conversion was obtained according to the polymerization conditions based on the curve. In addition, the polymerization conversion ratio may include an error range depending on the measurement.

Further, the polymerization may be carried out at a temperature ranging from 30 ° C to 70 ° C.

Meanwhile, the polymerization may be carried out by emulsion polymerization, and specifically, it may be carried out by the following method 1 or 2.

Hereinafter, the polymerization will be specifically described by dividing it into Method 1 or Method 2.

Method 1

The polymerization may be carried out by adding a vinyl chloride-based monomer and a vegetable oil-based defoaming agent to a seed mixture containing a first seed and a second seed, and performing a polymerization reaction. At this time, the vegetable oil defoaming agent may be added at a specific conversion rate after the start of the polymerization reaction as described above.

The seed mixture is used for enhancing the bonding force of the vinyl chloride monomer and imparting a bimodal effect to the finally produced vinyl chloride polymer latex. The seed mixture is added in an amount of 1 part by weight to 10 parts by weight based on 100 parts by weight of the vinyl chloride monomer It can be used.

The seed mixture is not particularly limited and may include a first seed and a second seed at an appropriate weight ratio as desired. For example, the first seed and the second seed may be mixed at a weight ratio of 1: 1 to 5: 1 May include. Here, the first seed may have an average particle diameter (D ₅₀ ) of 0.5 μm to 1.0 μm, and the second seed may have an average particle diameter (D ₅₀ ) of 0.05 μm or more and less than 0.5 μm. That is, the first seed may be a particle having a relatively large diameter, and the second seed may be a particle having a relatively small diameter.

Specifically, the polymerization can be carried out by charging a vinyl chloride monomer and a vegetable oil defoaming agent into a vacuum reactor in which the seed mixture and the polymerization water are mixed, and performing a polymerization reaction. The vegetable oil defoaming agent can be carried out after a specific polymerization And may be added to the polymerization reaction at the conversion time point. The specific polymerization conversion time point may be 5% to 90%, specifically 5% to 20%, or 70% to 90%, more specifically 80% to 90% . ≪ / RTI >

The polymerization may be carried out while the first emulsifier is continuously added during the polymerization reaction. If necessary, additives such as a polymerization initiator, a molecular weight adjuster, and an electrolyte may be further added.

For example, the polymerization is carried out by adding 100 parts by weight of a vinyl chloride monomer to a vacuum reactor containing 100 parts by weight of a vinyl chloride monomer, and 1 part by weight to 10 parts by weight of polymerized water of 70 parts by weight to 120 parts by weight, The polymerization is initiated in the temperature range and the polymerization initiator is added in an amount of 0.02 part by weight to 0.05 part by weight based on 100 parts by weight of the vinyl chloride monomer at a specific polymerization conversion rate as described above. After the initiation of the polymerization, 0.7 to 1.5 parts by weight of the first emulsifier may be continuously added to 100 parts by weight of the vinyl chloride monomer. If necessary, 0.1 part by weight to 100 parts by weight of the vinyl chloride monomer may be added. 1.5 parts by weight of a polymerization initiator, 0.5 parts by weight to 2 parts by weight of an electrolyte, and 0.1 parts by weight to 1 part by weight of a molecular weight adjuster.

The polymerization initiator is not particularly limited and any one or more of a water-soluble polymerization initiator and an oil-soluble polymerization initiator can be used, and at least one selected from the group consisting of peroxycarbonates, peroxyesters and azo compounds can be used have. Specifically, the polymerization initiator is at least one selected from the group consisting of lauryl peroxide (LPO), diisopropyl peroxy dicarbonate, di-2-ethylhexyl peroxycarbonate (OPP), t-butyl peroxypivalate, Neodecanoate, and 2,2-azobisisobutyronitrile may be used alone or in combination of two or more.

Wherein the first emulsifier is selected from the group consisting of sodium lauryl sulfate, lauryl benzene sulfonate, alpha-olefin sulfonate, sodium lauryl ethoxylate sulfate, sodium octadecyl sulfate, sodium lauryl ether sulfate and straight chain alkyl benzene sulfonate It may be more than one kind selected.

The molecular weight regulator is not particularly limited, but may be, for example, mercaptans such as n-butyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan and the like.

The electrolyte is not particularly limited and includes, for example, potassium chloride, sodium chloride, potassium bicarbonate, potassium carbonate, potassium hydrogen sulfite, sodium hydrogen sulfite, sodium pyrophosphate, sodium pyrophosphate, tripotassium phosphate, trisodium phosphate, Potassium, and disodium hydrogenphosphate.

Meanwhile, the first seed and the second seed are microparticles prepared by polymerizing vinyl chloride monomers, respectively, and may be prepared to have an average particle size as described above by different polymerization methods.

For example, the first seed may be prepared by adding a polymerization initiator, a vinyl chloride monomer, and a first emulsifier to a polymerization reactor, homogenizing the mixture, and then emulsifying and condensing the mixture. If necessary, the first seed may be a polymerization water, a second emulsifier, May be used to further perform emulsion polymerization.

The polymerization initiator may be used in an amount of 0.01 to 2 parts by weight based on 100 parts by weight of the vinyl chloride monomer. The average particle diameter of the first seed may be adjusted according to the amount of the polymerization initiator used. For example, as the amount of the polymerization initiator used increases, the average particle diameter of the produced first seed may decrease. The polymerization initiator may be as described above.

The first emulsifier may be used in an amount of 0.1 part by weight to 5 parts by weight based on 100 parts by weight of the vinyl chloride monomer.

The homogenization may be performed by homogenizing for 1 hour to 3 hours using a homogenizer at a temperature of 20 DEG C or less, preferably 5 DEG C to 15 DEG C, though not particularly limited. At this time, the homogenizer is not particularly limited and conventional ones known in the art can be used. For example, a rotor-stator type homogenizer can be used.

The emulsion polymerization for preparing the first seed may be performed at a temperature of 30 ° C to 70 ° C. Specifically, the emulsion polymerization may be started by raising the temperature of the homogenization at 40 ° C to 50 ° C for 5 to 15 hours And then performing emulsion polymerization for a while.

The second seed may be prepared by adding a polymerization initiator, a first emulsifier, and a vinyl chloride monomer to a polymerization reactor and emulsifying and polymerizing the same, wherein the second seed is prepared by continuously carrying out polymerization while the second emulsifier is added during polymerization. , And the number of the polymerized water can be increased.

At this time, the polymerization initiator used in the second seed preparation may be a water-soluble polymerization initiator, and may be one or more selected from the group consisting of potassium persulfate, ammonium persulfate, and hydrogen peroxide.

The first emulsifier used for preparing the second seed may be used in an amount of 0.01 part by weight to 1 part by weight based on 100 parts by weight of the vinyl chloride monomer. The average particle diameter of the second seed prepared according to the amount of the first emulsifier used Can be adjusted. For example, as the amount of the first emulsifier used increases, the average particle diameter of the second seed may be increased.

The second emulsifier used in the preparation of the second seed may be continuously fed into the reactor during polymerization as described above, and may be used in an amount of 0.01 to 6 parts by weight based on 100 parts by weight of the vinyl chloride monomer.

In one embodiment of the present invention, the first emulsifier and the second emulsifier used in the first seed and the second seed may be the same material or different materials, and the specific species may be the same as the first emulsifier described above.

Method 2

The polymerization may be carried out by introducing a vinyl chloride monomer and a vegetable oil defoaming agent in the presence of a water-soluble polymerization initiator and performing a polymerization reaction, wherein the vegetable oil defoaming agent is added at the time of the above- . ≪ / RTI >

Specifically, the polymerization can be carried out by charging a vinyl chloride monomer and a vegetable oil-based defoaming agent into a vacuum reactor in which a first emulsifier, a water-soluble polymerization initiator and a polymerization water are mixed, and performing a polymerization reaction. The vegetable oil- And may be added at a specific polymerization conversion time point after initiation to participate in the polymerization reaction. At this time, the specific polymerization conversion time point may be as described above.

The polymerization may be carried out while the second emulsifier is continuously added during the polymerization reaction. If necessary, an additive such as a dispersant or a reaction inhibitor may be added.

For example, the polymerization is carried out in a vacuum reactor comprising 70 parts by weight to 120 parts by weight of polymerization water, 0.01 to 0.06 part by weight of the first emulsifier and 0.006 to 0.01 part by weight of a water-soluble polymerization initiator per 100 parts by weight of the vinyl chloride monomer 100 parts by weight of a vinyl chloride monomer is added to initiate polymerization at a temperature ranging from 30 to 70 DEG C, and 0.02 part by weight or more of a vegetable oil defoaming agent is added to 100 parts by weight of the vinyl chloride monomer at the time of the above- And 0.05 part by weight of the monomer is added to the polymerization. After the initiation of the polymerization, 0.7 to 1.5 parts by weight of the second emulsifier may be continuously added to 100 parts by weight of the vinyl chloride monomer.

The water-soluble polymerization initiator, the first emulsifier, and the second emulsifier may be the same as those described in the method 1.

In addition, the present invention provides a plastisol containing the vinyl chloride-based polymer latex and a molded article produced using the plastisol.

Specifically, the plastisol may include 100 parts by weight of the vinyl chloride-based polymer latex and 40 to 120 parts by weight of the plasticizer. If necessary, additives such as a dispersion diluent, a heat stabilizer, a viscosity reducing agent and a foaming agent are further included can do.

The term "plastisol" in the present invention refers to a mixture of a resin and a plasticizer so as to be processed into a molding, a mold or a continuous film by heating. For example, a paste in which a vinyl chloride polymer latex and a plasticizer are mixed Lt; / RTI >

The term "plasticizer " in the present invention may be an organic additive material which serves to improve moldability at high temperatures of the resin by adding thermoplastic resin to the thermoplastic resin.

The plasticizers and additives are not particularly limited and those customary in the art can be used.

Further, the molded article may be a paste molded product produced by pasting using a plastisol. The molded article may be manufactured using a plastisol containing the vinyl chloride-vinyl acetate copolymer according to an embodiment of the present invention, thereby exhibiting excellent physical properties.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. However, the following examples and experimental examples are provided for illustrating the present invention, and the scope of the present invention is not limited thereto.

Example  One

100 parts by weight of polymerization water at 50 캜, 0.018 parts by weight of sodium lauryl sulfate and 0.07 parts by weight of potassium persulfate (KPS) were put into a reactor having an internal volume of 1 m ³ equipped with a stirrer, and the reactor was vacuumed while stirring. 100 parts by weight of a vinyl chloride monomer was charged into a reactor in a vacuum state, and the temperature of the reactor was raised to 50 캜 to initiate polymerization. After the initiation of polymerization, 1.6 parts by weight of sodium lauryl sulfate was continuously added for 6 hours, and a vegetable oil defoaming agent dispersion (5.6% w / w) was added to the polymerization reaction at a polymerization conversion rate of 5%. The vegetable oil defoaming agent dispersion was prepared by adding a vegetable oil defoaming agent to water (25 ° C) at room temperature and stirring at 150 rpm. The vegetable oil defoaming agent was prepared by adding 5 wt% of a silicon mixture containing silicon particles and siloxane particles, . The vegetable oil defoaming agent dispersion was used in an amount such that the vegetable oil defoaming agent was 0.02 parts by weight per 100 parts by weight of the vinyl chloride monomer. Thereafter, when the internal pressure of the reactor reached 3.5 K / G, the internal temperature of the reactor was measured and the reaction terminated to obtain a vinyl chloride polymer latex.

Example  2

Except that a vegetable oil defoaming agent dispersion (5.6% w / w) was used in an amount such that the amount of the vegetable oil defoaming agent was 0.05 parts by weight relative to 100 parts by weight of the vinyl chloride monomer. A latex was obtained.

Example  3

A vinyl chloride polymer latex was obtained in the same manner as in Example 1 except that the vegetable oil defoaming agent dispersion (5.6% w / w) was added at a polymerization conversion rate of 50% to participate in the polymerization reaction.

Example  4

A vinyl chloride polymer latex was obtained in the same manner as in Example 1 except that the vegetable oil defoaming agent dispersion (5.6% w / w) was added at a polymerization conversion rate of 85% to participate in the polymerization reaction.

Example  5

100 parts by weight of polymerization water at 50 占 폚 and 0.002 parts by weight of copper sulfate (II), 4.5 parts by weight of the first seed and 1.6 parts by weight of the second seed were put in a 500 L high-pressure reactor and the reactor was vacuumed while stirring. 100 parts by weight of vinyl chloride monomer was charged into a reactor in a vacuum state, and then the internal temperature of the reactor was raised to 50 占 폚 and polymerization was carried out. At this time, the first seed was vinyl chloride polymer particles having an average particle diameter of 0.68 mu m, and the second seed was vinyl chloride polymer particles having an average particle diameter of 0.12 mu m. After initiation of the polymerization, 0.9 weight part of sodium lauryl sulfate was continuously fed into the reactor for 6 hours, and a vegetable oil defoaming agent dispersion (5.6% w / w) was added to the polymerization reaction at a polymerization conversion of 5%. The vegetable oil defoaming agent dispersion was prepared by adding a vegetable oil defoaming agent to water (25 ° C) at room temperature and stirring the mixture at 150 rpm. The vegetable oil defoaming agent was prepared by adding a silicon mixture containing silicon particles and siloxane particles to 5 The vegetable oil defoaming agent dispersion was used in an amount such that the vegetable oil defoaming agent was 0.02 parts by weight based on 100 parts by weight of the vinyl chloride monomer. Thereafter, when the internal pressure of the reactor reached 3.5 K / G, the internal temperature of the reactor was measured and the reaction terminated to obtain a vinyl chloride polymer latex.

Example  6

Except that the vegetable oil defoaming agent dispersion (5.6% w / w) was used in an amount such that the amount of the vegetable oil defoaming agent was 0.05 parts by weight relative to 100 parts by weight of the vinyl chloride monomer. A latex was obtained.

Example  7

A vinyl chloride polymer latex was obtained in the same manner as in Example 5 except that the vegetable oil defoaming agent dispersion (5.6% w / w) was added at a polymerization conversion rate of 50% to participate in the polymerization reaction.

Example  8

A vinyl chloride polymer latex was obtained in the same manner as in Example 5 except that the vegetable oil defoaming agent dispersion (5.6% w / w) was added at a polymerization conversion rate of 85% to participate in the polymerization reaction.

Comparative Example  One

100 parts by weight of polymerization water at 50 캜, 0.018 parts by weight of sodium lauryl sulfate and 0.07 parts by weight of potassium persulfate (KPS) were put into a reactor having an internal volume of 1 m ³ equipped with a stirrer, and the reactor was vacuumed while stirring. 100 parts by weight of a vinyl chloride monomer was charged into a reactor in a vacuum state, and the temperature of the reactor was raised to 50 캜 to initiate polymerization. After initiation of polymerization, 1.6 parts by weight of sodium lauryl sulfate was added continuously for 6 hours to participate in the polymerization reaction. Thereafter, when the internal pressure of the reactor reached 3.5 K / G, the reaction was terminated and a vinyl chloride polymer latex was obtained.

Comparative Example  2

100 parts by weight of polymerization water at 50 占 폚 and 0.002 parts by weight of copper sulfate (II), 4.5 parts by weight of the first seed and 1.6 parts by weight of the second seed were put in a 500 L high-pressure reactor and the reactor was vacuumed while stirring. 100 parts by weight of vinyl chloride monomer was charged into a reactor in a vacuum state, and then the internal temperature of the reactor was raised to 50 占 폚 and polymerization was carried out. At this time, the first seed was vinyl chloride polymer particles having an average particle diameter of 0.68 mu m, and the second seed was vinyl chloride polymer particles having an average particle diameter of 0.12 mu m. After initiation of the polymerization, 0.9 part by weight of sodium lauryl sulfate was continuously fed into the reactor for 6 hours to participate in the polymerization reaction. Thereafter, when the internal pressure of the reactor reached 3.5 K / G, the internal temperature of the reactor was measured and the reaction terminated to obtain a vinyl chloride polymer latex.

Comparative Example  3

A vinyl chloride polymer latex was obtained in the same manner as in Example 1 except that polydimethylsiloxane was used in place of the vegetable oil-based defoaming agent.

Comparative Example  4

A vinyl chloride type polymer latex was obtained in the same manner as in Example 1 except that FoamStar ^® A10 (Cognis) was used instead of the vegetable oil type defoaming agent.

Comparative Example  5

Except that the vegetable oil defoaming agent dispersion (5.6% w / w) was used in an amount such that the amount of the vegetable oil defoaming agent was 0.01 parts by weight relative to 100 parts by weight of the vinyl chloride monomer. A latex was obtained.

Comparative Example  6

Except that the vegetable oil defoaming agent dispersion (5.6% w / w) was used in an amount such that the amount of the vegetable oil defoaming agent was 0.1 parts by weight relative to 100 parts by weight of the vinyl chloride monomer. A latex was obtained.

Comparative Example  7

A vinyl chloride polymer latex was obtained in the same manner as in Example 1 except that the vegetable oil-based defoamer dispersion (5.6% w / w) was added prior to the initiation of polymerization and polymerization was started.

Comparative Example  8

A vinyl chloride polymer latex was obtained in the same manner as in Example 1 except that the vegetable oil defoaming agent dispersion (5.6% w / w) was added after completion of the polymerization reaction.

Comparative Example  9

Except that the vegetable oil defoaming agent dispersion (5.6% w / w) was used in an amount such that the amount of the vegetable oil defoaming agent was 0.01 part by weight relative to 100 parts by weight of the vinyl chloride monomer. A latex was obtained.

Comparative Example  10

Except that the vegetable oil defoaming agent dispersion (5.6% w / w) was used in an amount such that the amount of the vegetable oil defoaming agent was 0.1 parts by weight relative to 100 parts by weight of the vinyl chloride monomer. A latex was obtained.

Comparative Example  11

A vinyl chloride polymer latex was obtained in the same manner as in Example 5 except that the vegetable oil defoaming agent dispersion (5.6% w / w) was added before the initiation of polymerization and polymerization was started.

Comparative Example  12

A vinyl chloride polymer latex was obtained in the same manner as in Example 5 except that the vegetable oil defoaming agent dispersion (5.6% w / w) was added after completion of the polymerization reaction.

Experimental Example  One

In order to comparatively analyze the dispersibility of the defoamer dispersion used in Example 1, Comparative Example 3 and Comparative Example 4, changes were observed immediately after the preparation (immediately after mixing), after 30 minutes of standing, and after 100 minutes of standing. The results are shown in Fig.

As shown in Fig. 1, the vegetable oil defoaming agent dispersion of Example 1 including the vegetable oil defoaming agent according to the present invention had excellent dispersibility in water and was uniformly dispersed without causing layer separation even after being left for a long time Respectively.

On the other hand, in the defoamer dispersions of Comparative Example 3 and Comparative Example 4 which include the conventionally known polydimethylsiloxane and the commercialized FoamStar ^® A10, layer separation occurred with the passage of time, and in particular, FoamStar ^® A10 was neglected After 30 minutes, it was confirmed that the layer separation occurred conspicuously.

Experimental Example  2

The content of defoamer in each of the vinyl chloride polymer latexes prepared in Examples 1 to 8 and Comparative Examples 1 to 12 was measured and the degree of inhibition of bubble formation and the stability of reaction of the latex were compared and analyzed. The results are shown in Table 2 below.

The content of defoamer in the vinyl chloride polymer latex was measured by liquid chromatography (LC) analysis. Specifically, each of the vinyl chloride polymer latexes was dried to prepare a powder, and 1 part by weight of each of the vinyl chloride polymer powders was added to 100 parts by weight of a tetrahydrofuran (THF) solution. The resulting mixture was dissolved at room temperature, And the supernatant was extracted and filtered to prepare analytical samples, respectively. Each prepared analytical sample was quantitatively analyzed using an Aquilty UPLC (Ultra Performance Liquid Chromatography, Waters) apparatus and a Xevo G2-S QTof mass spectrometer.

The degree of inhibition of foaming was evaluated by placing 1 L of each vinyl chloride polymer latex into a beaker, generating bubbles by using a bubble generator, measuring the volume increase rate. At this time, the air bubble was injected into the bubble generator at an air flow rate of 10 L / min, and the volume increase rate was measured at 5 minutes after the injection. The foam inhibition degree evaluation was evaluated by a five-point method, and specific evaluation criteria are shown in Table 1 below.

In addition, the above reaction stability was compared with the internal temperature of the reactor measured before completion of the polymerization reaction.

Foam level Volume increase rate
(Amount of bubble generated per latex input) 1 (very good) 10 to less than 20 2 (excellent) 20 to less than 40 3 (usually) 40 to less than 50 4 (thirteen) 50 to less than 100 5 (very poor) 100 or more

division Defoaming agent content (parts by weight) Bubble generation inhibition (point) Reaction stability (캜) Example 1 0.02 3 75 Example 2 0.05 2 68 Example 3 0.02 2 70 Example 4 0.02 One 62 Example 5 0.02 3 71 Example 6 0.05 2 64 Example 7 0.02 2 65 Example 8 0.02 One 58 Comparative Example 1 - 5 85 Comparative Example 2 - 5 75 Comparative Example 3 0.02 4 83 Comparative Example 4 0.02 4 85 Comparative Example 5 0.01 5 85 Comparative Example 6 0.1 2 64 Comparative Example 7 0.02 5 82 Comparative Example 8 0.02 One 83 Comparative Example 9 0.01 5 73 Comparative Example 10 0.1 2 65 Comparative Example 11 0.02 5 72 Comparative Example 12 0.02 One 78

As shown in Table 2, the vinyl chloride polymer latexes of Examples 1 to 8 according to one embodiment of the present invention had less foaming than vinyl chloride polymer latexes of Comparative Examples 1 to 12 and had excellent reaction stability Respectively. Here, the term "excellent in the reaction stability" means that there is little difference in temperature between the polymerization reaction and the stability of the prepared vinyl chloride polymer latex is small, because the temperature rise at the end of the reaction is small at the end of the reaction. As a result, The residual monomers can be easily removed in the residual monomer stripping step for removing the unreacted monomers in the vinyl polymer latex and applied to the production of the final molded product to ensure excellent storage stability.

Specifically, each of the vinyl chloride polymer latexes of Example 1 and Example 5 according to one embodiment of the present invention had a foam generation rate lower than that of the vinyl chloride polymer latex of Comparative Example 1 and Comparative Example 2 produced without using a defoaming agent And the reaction stability was excellent.

In addition, in the case of the vinyl chloride polymer latexes of Comparative Example 3 and Comparative Example 4 which were produced by using conventional antifoaming agents, the degree of foaming was somewhat reduced compared to the vinyl chloride polymer latex of Comparative Example 1 in which no defoaming agent was used , No significant effect on the reaction stability was observed. In comparison with the vinyl chloride polymer latex of Example 1, foaming was increased and the reaction stability was greatly reduced.

The vinyl chloride polymer latexes of Comparative Example 5 and Comparative Example 9, which contained less than the defoamer content of the present invention, had the same level as the vinyl chloride polymer latexes of Comparative Example 1 and Comparative Example 2, Bubbles were generated and the end-of-reaction temperature rose. This means that when the antifoaming agent is contained in an amount smaller than the amount of the antifoaming agent proposed in the present invention, it can not have an effective effect on the foaming suppression and the reaction stability.

On the other hand, in the case of the vinyl chloride polymer latexes of Comparative Example 6 and Comparative Example 10 which contained more than the defoamer content of the present invention, the degree of foaming was as high as that of the vinyl chloride polymer latex of Example 2 and Example 6 However, the effect of suppressing the foaming and the end-of-reaction temperature rise is insignificant compared with the amount of the defoaming agent used, and rather, due to the excessive defoaming agent, the viscosity is increased due to the viscosity increase during the production of the molded article using the vinyl chloride polymer latex, There arises a problem that pinholes are generated in the produced molded article to lower the surface characteristics, and thus the practical application is limited.

In preparing the vinyl chloride polymer latex, the vinyl chloride polymer latexes of Comparative Example 7 and Comparative Example 11 prepared by adding the defoamer before the initiation of polymerization, not at the time of introduction as shown in the present invention, Foam generation was increased compared to the vinyl chloride polymer latex (each time the defoaming agent was added at a polymerization conversion rate of 5%), and the effect of suppressing the temperature rise at the end of the reaction was not exhibited. On the other hand, the vinyl chloride polymer latex of Comparative Example 8 and Comparative Example 12 prepared by adding the defoamer after completion of polymerization had an excellent foam inhibiting effect. However, after the completion of the polymerization reaction, The stability of the latex was poor, and as a result, there was a problem that the storage processability was low.

Claims (14)

100 parts by weight of vinyl chloride monomer-derived units; And
0.0 > 0.05 < / RTI > parts by weight of a vegetable oil-based antifoaming agent based on 100 parts by weight of the derived unit,
Wherein the vegetable oil-based defoaming agent comprises a silicon-based mixture comprising silicon particles and siloxane particles.
The method according to claim 1,
Wherein the vegetable oil-based defoaming agent comprises rapeseed oil.
The method according to claim 1,
Wherein the vegetable oil-based antifoaming agent comprises 1 to 10% by weight of a silicon-based mixture.
The method according to claim 1,
Wherein the silicon particles and the siloxane particles independently have an average particle diameter (D ₅₀ ) of 1 to 2 μm.
100 parts by weight of a vinyl chloride monomer and 0.02 part by weight to 0.05 part by weight of a vegetable oil defoaming agent,
The vegetable oil-based defoaming agent includes a silicon-based mixture,
The method for producing a vinyl chloride-based polymer latex according to claim 1, wherein the silicon-based mixture comprises silicon particles and siloxane particles.
The method of claim 5,
Wherein the vegetable oil-based defoaming agent is introduced at a time point of 5 to 90% after initiation of the polymerization reaction.
The method of claim 5,
Wherein the vegetable oil-based defoaming agent is added at a time point of 5% to 20% or 70% to 90% after initiation of the polymerization reaction.
The method of claim 5,
Wherein the vegetable oil-based antifoaming agent is introduced at a time point of 80 to 90% after initiation of the polymerization reaction.
The method of claim 5,
Wherein the polymerization is carried out by charging a vinyl chloride-based monomer and a vegetable oil-based defoaming agent into a seed mixture containing a first seed and a second seed, and performing a polymerization reaction.
The method of claim 9,
Wherein the seed mixture is used in an amount of 1 part by weight to 10 parts by weight based on 100 parts by weight of the vinyl chloride monomer.
The method of claim 9,
Wherein the seed mixture contains the first seed and the second seed at a weight ratio of 1: 1 to 5: 1.
The method of claim 9,
The first seed has an average particle diameter (D ₅₀ ) of 0.5 탆 to 1.0 탆,
Wherein the second seed has an average particle diameter (D ₅₀ ) of 0.05 탆 or more and less than 0.5 탆.
The method of claim 5,
Wherein the polymerization is carried out by introducing a vinyl chloride monomer and a vegetable oil defoaming agent in the presence of a water-soluble polymerization initiator and performing a polymerization reaction.
The method of claim 5,
Wherein the polymerization is carried out in a temperature range of from 30 캜 to 70 캜.

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