KR20180066699A - Cellulose ether with improved association property, a method of manufacturing the same, and associative thickeners including the same - Google Patents

Abstract

The present invention relates to cellulose ether with an excellent association property, a manufacturing method for the same, and an associative thickener including the same. The cellulose ether includes multiple hydroxyls (-OH) in a molecule. A part of the hydroxyl (-OH) is substituted to a functional group indicated by chemical formula A-O-(C_nH_2nO)_m (In chemical formula 1, Ai is a hydrophobic group selected in a group comprising an alkyl group, an arylalkyl group, an alkenyl group, an arylalkenyl group, a cycloaliphatic group, a perfluoroalkyl group, a carbosilyl group, and a polycyclyl group). According to the present invention, the cellulose ether with the excellent association property can be provided. Also, the associative thickener capable of manufacturing water-based paint having excellent ICI viscosity by including the cellulose ether can be provided.

Description

TECHNICAL FIELD The present invention relates to a cellulose ether having improved crystallinity, a process for producing the cellulose ether, and a concomitant thickener containing the same.

More particularly, the present invention relates to a cellulose ether having improved recycling by replacing a part of hydroxyl groups present in a cellulose ether molecule with a specific functional group, and more particularly, to a cellulose ether having improved recycling, And a method for producing the same and a concomitant thickener containing the same.

Generally, associative thickener refers to a water-soluble or water-dispersible polymer compound having a hydrophobic group. Such associative thickeners can be used in various aqueous systems such as rheological agents such as automotive and industrial coatings, finishes and paints, dyes for printing inks and fabrics, pigment printing pastes, pharmaceutical and cosmetic compositions, plant protection formulations and filler dispersions It is used as an adjuvant to control the characteristics.

For instance, in the case of water-based paints, when the shear rate is high, the apparent viscosity is low and therefore it is easy to be painted, and after the external force is removed, the viscosity is restored so that it is coated with a proper film thickness, (Thixotrophy) is required. A small amount of thickener is used to satisfy such properties. The thickener imparts a high viscosity by forming a resin and a pigment with a net structure in the paint, and the net structure is easily broken due to a high shearing force at the time of coating, thereby lowering the viscosity of the paint, Removing the force externally causes the broken net structure to recover again, causing the viscosity of the paint to rise so that the painted paint does not flow.

The thickener is used as an additive for water-based paint in addition to thixotropy for the purpose of preventing layer separation of paint, improving workability, thickening property, leveling property and water retention property. A representative example of the thickener is cellulose ether.

Generally, cellulose ethers for aqueous paint thickeners include hydroxyethyl cellulose (HEC), hydroxy-ethyl cellulose (HM-HEC) substituted with a hydrophobic group, and hydroxypropylmethylcellulose (Hydroxypropylmethyl Cellulose, HPMC) are mainly used.

Specifically, the hydroxypropylmethylcellulose has a good thickening efficiency and thus has the advantage of obtaining a high paint viscosity even when used in a small amount. However, the coloring ability is deteriorated and the appearance of color deteriorates due to the addition of the same pigment, .

On the other hand, hydroxyethyl cellulose has an advantage in that it exhibits excellent color development and bubble formation, but has drawbacks in that workability is low and the viscosity efficiency is low due to severe spatter during roller or brushing operation.

In order to solve this problem, a method of using a concomitant thickener having a hydrophilic group substituted with a hydrophobic group and imparting a conformation has been studied.

For example, Patent Document 1 (Korean Patent Laid-Open No. 10-2001-0075666) describes a method of using a cellulose derivative modified by hydrophobicity or a guar derivative modified by hydrophobicity as a associative thickener. As the cellulose derivatives modified with the hydrophobic there is C ₁₀ ~ C ₂₄ alkyl and C ₁₀ ~ C ₂₄ aryl alkyl hydrophobic groups in the hydroxyethyl cellulose modified by hydrophobic selected from is illustrated.

Such hydrophobically modified hydroxyalkylcellulose contains a hydrophilic group present in conventional hydroxyalkylcellulose in a hydrophobic monomer in the form of a monomolecular form such as a halogenated alkyl or halogenated alkylaryl having 10 to 24 carbon atoms (C ₁₀ to C ₂₄ ) With a substituted hydrophobic group.

However, hydroxy-ethyl cellulose (HM-HEC) substituted with a simple hydrophobic group such as the C ₁₀ -C ₂₄ alkyl group or the C ₁₀ -C ₂₄ alkylaryl group has limitations in having free association with the emulsion . Therefore, when the HM-HEC is used as a thickener, a desired level of cohesive force can not be imparted and the viscosity efficiency is lowered. As a result, when the water-based paint is manufactured using the thickener, have. As used herein, ICI viscosity refers to the viscosity of an aqueous paint at high shear, which is related to the physical properties of the paint during roller application. Generally, when the ICI viscosity is low, there are many paint rolls by the rollers, which results in poor workability of the rollers.

KR 1020010075666 A

Disclosure of Invention Technical Problem [8] The present invention provides a cellulose ether having excellent recrystallization by substituting a certain functional group for a part of hydroxy groups present in the cellulose ether molecule, and a process for producing the same.

Also, the present invention is to provide a concomitant thickener capable of producing an aqueous paint having excellent ICI viscosity by containing cellulose ether excellent in recyclability as described above.

In order to solve the above problems, the present invention provides a cellulose ether comprising a plurality of hydroxyl groups (-OH) in a molecule, characterized in that a part of the hydroxyl group (-OH) is substituted with a functional group represented by the following formula (Hereinafter, the cellulose ether before the functional group is substituted is referred to as "cellulose ether ", and the cellulose ether substituted with the functional group is referred to as" recycled cellulose ether ").

Formula 1

AO- (C _n H _2n O) _m -

In Formula 1, A is a hydrophobic group selected from the group consisting of an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, an arylalkenyl group, a cycloaliphatic group, a perfluoroalkyl group, a carbosilyl group, Is 1-5 and m is 5-50.

The hydrophobic group selected from the alkyl group, the alkenyl group, the perfluoroalkyl group and the carbosilyl group includes 1 to 40 carbon atoms, the cycloaliphatic group includes 3 to 40 carbon atoms, and the aryl group, arylalkyl group, The hydrophobic group selected from an arylalkenyl group and a polycyclyl group may contain 6 to 40 carbon atoms.

The substitution degree of the functional group may be 0.4 to 2.0 wt%.

The cellulose ether may be at least one selected from the group consisting of alkyl cellulose, hydroxyalkyl cellulose, hydroxyalkyl alkyl cellulose and alkylalkyl hydroxyalkyl cellulose. And may preferably be hydroxyethyl cellulose having a degree of substitution (MS) of 62 to 78 wt%.

According to another aspect of the present invention, there is provided a method for producing a cyclic cellulose ether comprising the steps of: (1) reacting cellulose with an alkalizing agent to obtain an alkalized cellulose; (2) reacting the alkalized cellulose with an etherifying agent to obtain a cellulose ether; And (3) reacting the cellulose ether with an alkalizing agent, a coupling agent, and a compound represented by the following formula (2) to prepare a con- nected cellulose ether.

(2)

_{AO- (C n H 2n O)} m -H

In Formula 2, A is a hydrophobic group selected from the group consisting of an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, an arylalkenyl group, a cycloaliphatic group, a perfluoroalkyl group, a carbosilyl group, Is 1-5 and m is 5-50.

The cellulose ether produced in step (2) may be hydroxyalkyl cellulose. In step (2), the alkaline cellulose is reacted with the first etherizing agent according to step (1) Obtaining a hydroxyalkylcellulose; And reacting the first hydroxyalkylcellulose with a second etherifying agent to obtain a second hydroxyalkylcellulose. At this time, the step (2) may further include partially neutralizing the first hydroxyalkylcellulose with an acid.

The coupling agent may include one or more selected from the group consisting of methylene bromide (CH ₂ Br ₂ ), dichloroethane (C ₂ H ₄ Cl ₂ ), and diglycidyl ether .

The present invention also provides a concomitant thickener comprising the above-mentioned conglomerated cellulose ether.

In the associative cellulose ether according to the present invention, a part of the hydroxyl groups present in the molecule can be substituted with the functional group represented by the above-mentioned formula (1), thereby exhibiting excellent crystallization.

Accordingly, the present invention can provide an aqueous paint having excellent ICI viscosity by using the associative thickener containing the above-mentioned recycled cellulose ether.

Such water-based paints have an excellent resistance to scratches required when the roller is working, and as a result, roller workability can be improved.

The present invention relates to a synthetic cellulose ether, a process for producing the same, and a concomitant thickener containing the same.

First, the ash-soluble cellulose ether according to the present invention will be described below.

The present invention relates to a cellulose ether comprising a plurality of hydroxyl groups (-OH) in a molecule, wherein a part of the hydroxyl group (-OH) is substituted with a functional group represented by the following formula (1) do.

Formula 1

AO- (C _n H _2n O) _m -

In Formula 1, A is a hydrophobic group selected from the group consisting of an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, an arylalkenyl group, a cycloaliphatic group, a perfluoroalkyl group, a carbosilyl group, Is 1-5 and m is 5-50.

The hydrophobic group selected from the alkyl group, alkenyl group, perfluoroalkyl group and carbosilyl group in A includes 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 10 to 16 carbon atoms . The cycloaliphatic group may contain 3 to 40 carbon atoms, preferably 6 to 29 carbon atoms, and more preferably 7 to 16 carbon atoms. The hydrophobic group selected from the aryl group, arylalkyl group, arylalkenyl group and polycyclyl group may contain 6 to 40 carbon atoms, preferably 6 to 29 carbon atoms, more preferably 7 to 16 carbon atoms.

In the above formula (1), n may preferably be 2. The above-mentioned m may preferably be 5 to 20, more preferably 5 to 15.

Specifically, the functional group represented by the formula (1) is a hydrophobic compound having a hydrophobic group and a polyoxyalkylene group (- (C _n H _2n -O) _m - (HO- (C _n H _2n ) _m -OH) which is a hydrophilic compound.

These functional groups are substituted with a part of hydroxyl groups present in the cellulose ether molecule to produce a conformational cellulose ether having a hydrophobic group in the molecule and having water-soluble or water-dispersible properties. When such a conglomerated cellulose ether is applied to an aqueous coating composition such as an aqueous paint or the like, a hydrophilic group present in the conglomerated cellulose ether molecule is present in the other conglomerated cellulose ether molecule present in the aqueous system and / They associate with hydrophobic groups of other hydrophobic substances and exert their thickening effect.

In particular, according to the present invention, a functional group derived from a long-molecular-type conjugate complex as shown in Formula 1 is introduced into a cellulose ether molecule, whereby a hydrophobic group derived from a conventional monomolecular- Free associative connection with the emulsion which could not be obtained, and consequently the synthesis of the final thickener can be strengthened.

The degree of substitution of the functional group represented by Formula 1 may be 0.4 to 2.0 wt%. When the degree of substitution of the functional group is less than 0.4 wt%, the effect of improving the syneresis may be insufficient. On the other hand, when the degree of substitution is more than 2 wt%, the hydrophobicity becomes excessively high and it is difficult to apply it to a water-soluble coating composition such as an aqueous paint. Here, the substitution degree of the functional group means the average wt% of the functional group based on the weight of the associative cellulose ether.

The cellulose ethers used to provide the associative cellulose ether according to the present invention include alkyl cellulose, hydroxyalkyl cellulose, hydroxyalkyl alkyl cellulose and alkyl alkyl hydroxyalkyl cellulose and alkylalkyl hydroxyalkyl cellulose.

Preferably, the cellulose ether may be hydroxyethyl cellulose having a degree of substitution (MS) of hydroxyethyl group of 62 to 78 wt%. If the degree of substitution (MS) of the hydroxyethyl group is less than 62 wt%, the substitution efficiency of the functional group represented by the formula (1) may be lowered. On the other hand, when the degree of substitution is more than 78 wt%, the production efficiency decreases and the product surface becomes excessively sticky Production and use can be difficult. Here, the degree of substitution (MS) of the hydroxyethyl group means the average wt% of the hydroxyethyl group based on the weight of the cellulose ether.

According to another aspect of the present invention, there is provided a method for producing the associative thickener, comprising the steps of: (1) reacting cellulose with an alkalizing agent to obtain an alkalized cellulose; (2) reacting the alkalized cellulose with an etherifying agent to obtain a cellulose ether; And (3) reacting the cellulose ether with an alkalizing agent, a coupling agent, and a compound represented by the following formula (2) to prepare a con- nected cellulose ether.

(2)

_{AO- (C n H 2n O)} m -H

In Formula 2, A is a hydrophobic group selected from the group consisting of an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, an arylalkenyl group, a cycloaliphatic group, a perfluoroalkyl group, a carbosilyl group, Is 1-5 and m is 5-50.

Hereinafter, a method for producing the cyclic cellulose ether according to the present invention will be described in detail.

(1) Step of obtaining alkalized cellulose

This step is a step of reacting cellulose with an alkalizing agent to obtain an alkalized cellulose.

The step of obtaining the alkalized cellulose may be carried out without limitation according to a conventional method generally used in this field. For example, after the cellulose is put into a reaction solvent, an alkalizing agent is added thereto to alkalize the cellulose Cellulose may be used.

Specifically, the cellulose may be finely pulverized raw pulp, and the reaction solvent may include one or more selected from the group consisting of water, acetone, tertiary butyl alcohol, isopropyl alcohol, and dimethyl ether. At this time, the amount of the reaction solvent may be 50 to 2000 parts by weight based on 100 parts by weight of the cellulose.

The alkalizing agent may include an alkali metal hydroxide. For example, the alkalizing agent may include one or more selected from the group consisting of sodium hydroxide, potassium hydroxide, and lithium hydroxide. The amount of the alkalizing agent may be 5 to 600 parts by weight based on 100 parts by weight of the cellulose. If the amount of the alkalizing agent is within the above range, the etherifying agent is uniformly substituted in the whole of the cellulose in the step (2) to be described later, and the reactivity of the etherating agent is increased, so that the cellulose ether having the desired degree of substitution can be obtained.

The purpose of introducing the alkalizing agent is to weaken the crystal structure of the cellulose so that the etherating agent described later and the cellulose can easily react. That is, the alkalizing agent plays a role of promoting the reaction of the cellulose with the etherifying agent. The alkali-converted cellulose thus converted must be agitated at room temperature (20 to 30 ° C) for a certain period of time, so that its crystal structure can be uniformly weakened.

(2) Step of obtaining cellulose ether

This step is a step of obtaining cellulose ether by reacting alkalized cellulose with etherification according to the above step (1).

This step may also be carried out without limitation according to a conventional method generally used in this field as in the step (1). For example, a method in which an etherifying agent is added to an alkaline-containing cellulose, followed by heating to react can be used.

Specifically, the etherifying agent may be at least one alkylene oxide compound selected from propylene oxide and ethylene oxide; And one or more alkyl chloride compounds selected from methyl chloride, ethyl chloride, propyl chloride and butyl chloride.

The amount of the etherifying agent may be 20-400 parts by weight based on 100 parts by weight of the cellulose. If the amount of the etherifying agent is within the above range, the risk of an abnormal reaction and formation of by-products are reduced in the process, and cellulose ether having a desired degree of substitution can be obtained.

When the cellulose ether prepared according to the step (2) is hydroxyalkylcellulose, the step (2) comprises reacting the alkalized cellulose with the first etherating agent according to the step (1) Obtaining an alkyl cellulose; And reacting the first hydroxyalkylcellulose with a second etherifying agent to obtain a second hydroxyalkylcellulose. The first hydroxyalkylcellulose may further be partially neutralized by an acid before being reacted with the secondary etherating agent. When the partial neutralization step is further carried out in this manner, the substitution of the alkyl group becomes uniform and the efficiency of substitution of the hydrophilic group can be increased.

The second hydroxyalkylcellulose thus prepared may be hydroxyethylcellulose having a degree of substitution (MS) of hydroxyethyl group of 62 to 78 wt%.

(3) a step of producing a cyclic cellulose ether

This step is a step of reacting the cellulose ether prepared according to the step (2) with an alkalizing agent, a coupling agent and a compound represented by the following formula (2) to prepare a con- nected cellulose ether.

(2)

_{AO- (C n H 2n O)} m -H

In Formula 2, A is a hydrophobic group selected from the group consisting of an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, an arylalkenyl group, a cycloaliphatic group, a perfluoroalkyl group, a carbosilyl group, Is 1-5 and m is 5-50.

The hydrophobic group selected from the alkyl group, alkenyl group, perfluoroalkyl group and carbosilyl group in A includes 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 10 to 16 carbon atoms . The cycloaliphatic group may contain 3 to 40 carbon atoms, preferably 6 to 29 carbon atoms, and more preferably 7 to 16 carbon atoms. The hydrophobic group selected from the aryl group, arylalkyl group, arylalkenyl group and polycyclyl group may contain 6 to 40 carbon atoms, preferably 6 to 29 carbon atoms, more preferably 7 to 16 carbon atoms.

In the above formula (1), n may preferably be 2. The above-mentioned m may preferably be 5 to 20, more preferably 5 to 15.

The alkalizing agent serves to uniformly substitute the compound represented by the general formula (2) in the whole of the cellulose ether, and may include an alkali metal hydroxide. For example, the alkalizing agent may include one or more selected from the group consisting of sodium hydroxide, potassium hydroxide, and lithium hydroxide. The amount of the alkalizing agent may be 20 to 45 parts by weight based on 100 parts by weight of the cellulose. When the amount of the alkalizing agent is less than 20 parts by weight, alkalization of the cellulose ester is not sufficient and the substitution of the etherifying agent may be uneven. On the other hand, when the amount of the alkaline agent is more than 45 parts by weight, Excessive reaction may occur and hydrophobicity may be excessively high.

The coupling agent is added to increase the binding force between the cellulose ether and the compound represented by Chemical Formula 2 and includes methylene bromide (CH ₂ Br ₂ ), dichloroethane (C ₂ H ₄ Cl ₂ ), and di And diglycidyl ether. The term " glycidyl ether " The amount of the coupling agent may be 0.1 to 20 parts by weight based on 100 parts by weight of the cellulose. When the amount of the coupling agent is less than 0.1 parts by weight, the effect of the addition may be insufficient. On the other hand, when the amount of the coupling agent is more than 20 parts by weight, discoloration may be caused.

In addition, the method for producing the cyclic cellulose ether according to the present invention may further include neutralizing the cyclic cellulose ether prepared in the step (3).

The neutralization step may be carried out without limitation according to a conventional method generally used in this field, for example, by neutralizing a neutralizing agent in a synthetic cellulose ether. As the neutralizing agent, all oxidizing agents can be used. For example, nitric acid, acetic acid, hydrochloric acid and the like are mainly used, and they can be used in a diluted state of 40 to 90%.

According to the present invention, there is provided a concomitant thickener comprising the above-mentioned recycled cellulose ether.

Since the associative thickener includes a cellulose ether into which a functional group derived from a long molecular type of a hydrophilic complex is introduced, when it is applied to an aqueous paint, free associative connection with the emulsion contained in the water-based paint becomes possible, .

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these embodiments.

Example 1

10 kg of cellulose (Rayonier, Ethenier-F) was put in a pressure reactor and 90 kg of a mixed solvent of tertiary butyl alcohol / isopropyl alcohol / water (weight ratio = 83: 6: 11) as a reaction solvent was added, and then 50% sodium hydroxide Was added thereto and reacted with stirring at 25 DEG C to obtain an alkalized cellulose.

Next, 3.52 kg of ethylene oxide was added to the reactor, and the reaction temperature was raised to 85 ° C., and then the first etherification reaction was carried out at the same temperature for 60 minutes to synthesize the first hydroxyethyl cellulose. Then, the temperature of the reactor was cooled to 60 DEG C, and 5.54 kg of 70% nitric acid as a neutralizing agent was added thereto for partial neutralization. At this time, the neutralization ratio is 75%. After the partial neutralization was completed, 8.54 kg of ethylene oxide was added, the reaction temperature was raised to 100 ° C, and then the second etherification reaction was carried out at the same temperature for 60 minutes to synthesize the second hydroxyethyl cellulose. At this time, the substitution degree of the hydroxyethyl group of the second hydroxyethyl cellulose is 62.6 wt%.

Next, 3.5 kg of a 50% sodium hydroxide solution as an alkalizing agent, 0.25 kg of methylene bromide as a coupling agent, and 1.25 kg of an alkyl polyethylene ether were charged in the reactor synthesized with the second hydroxyethylcellulose, and the reaction temperature was raised to 120 ° C , And the reaction was carried out at the same temperature for 180 minutes. At this time, the formulas of the alkylpolyethylene ether are shown in Table 1 below.

The temperature of the reactor was then cooled to 60 DEG C and neutralized by the addition of 5.9 kg of a 70% nitric acid solution as a neutralizing agent. After the neutralization was completed, the mixture was washed with a mixed solvent of acetone / water (weight ratio = 90: 10) and dried to obtain recovered hydroxyethylcellulose. At this time, the substitution degree of the functional group derived from the alkylpolyethylene ether in the produced concomitant hydroxyethylcellulose was 0.49 wt%.

Examples 2 to 7

The same procedure as in Example 1 was carried out except that the amount of ethylene oxide charged in the primary etherification reaction and the secondary etherification reaction, and the formula and charge amount of the alkylpolyethylene ether were changed as shown in the following Table 1 To prepare synthesized hydroxyethylcellulose. At this time, the degree of substitution of hydroxyethyl group of the hydroxyethyl cellulose produced by the secondary etherification reaction and the degree of substitution of functional group of associative hydroxyethyl cellulose are shown in Table 1 below.

Comparative Example 1

Hydrophobically modified hydroxyethyl cellulose (HM-HEC) (Lotte Fine Chemicals) was prepared. At this time, the substitution degree of the hydroxyethyl group of the HM-HEC is 64.5 wt%, and the substitution degree of the alkyl group (C ₁₂ H ₂₅ -) which is a hydrophobic group is 0.56 wt%.

Comparative Example 2

Hydrophobically modified hydroxyethyl cellulose (HM-HEC) (Lotte Fine Chemicals, HM500) was prepared. At this time, the substitution degree of the hydroxyethyl group of the HM-HEC is 68.2 wt% and the substitution degree of the alkyl group (C ₁₂ H ₂₅ -) which is a hydrophobic group is 0.74 wt%.

<Evaluation method>

1. ICI Viscosity

In order to evaluate the ICI viscosity, water-soluble paints were first prepared using the concomitant hydroxyethylcellulose prepared according to Examples 1 to 7 and the HM-HEC prepared according to Comparative Examples 1 and 2 as associative thickener.

Concretely, the water-soluble paint was composed of 13.0% by weight of titanium dioxide (TiO ₂ ) / 7.0% by weight of aluminum silicate as an extender pigment, 13.0% by weight of calcium carbonate and 5.0% by weight of talc / acrylic emulsion (Acronal ^® 559, BASF 0.3% by weight of dispersant (44S, Sanocof Co., Ltd) 0.5% by weight of antifoaming agent (SN-1300, Sanocof Co., Ltd) 0.3% by weight of freezing agent (CF- (Texanol ™, Eastman chemical company) 1.0% by weight / pH adjusting agent (AMP-95 ^® , Eastman chemical company), 1.5% by weight of an antiseptic agent (ethylene glycol), 0.2% by weight of Troysan 174, Troy chemical corp. 0.2% by weight / 5% by weight of a synthetic thickener / 36% by weight of water.

The ICI viscosity of the water-soluble paint was measured at 25 캜 using an ICI viscometer (REL, Cone & Plate viscometer).

Ethylene
Oxide (kg) Alkylpolyethylene ether Hydroxy
Ethyl group
Degree of substitution
(wt%) Functional group
Degree of substitution
(wt%) Alkyl group
Degree of substitution
(wt%) ICI
Viscosity
(poise) Primary Secondary The input
(kg) Example 1 3.52 8.54 _{(CH 2) 12 -O- (CH} 2 CH 2 O) 5 -H 1.25 62.6 0.49 - 0.85 Example 2 3.75 10.15 _{(CH 2) 12 -O- (CH} 2 CH 2 O) 5 -H 1.36 67.5 0.92 - 0.88 Example 3 3.48 8.72 (CH ₂ ) ₁₂ -O- (CH ₂ CH ₂ O) ₁₀ -H 1.94 63.5 0.76 - 0.86 Example 4 3.81 10.3 (CH ₂ ) ₁₂ -O- (CH ₂ CH ₂ O) ₁₀ -H 2.23 69.8 1.42 - 0.92 Example 5 3.45 8.61 (CH ₂ ) ₁₂ -O- (CH ₂ CH ₂ O) ₁₅ -H 2.62 62.9 1.03 - 0.87 Example 6 3.71 10.06 (CH ₂ ) ₁₂ -O- (CH ₂ CH ₂ O) ₁₅ -H 2.91 68.5 1.92 - 0.98 Example 7 3.85 10.36 (CH ₂ ) ₁₆ -O- (CH ₂ CH ₂ O) ₁₀ -H 2.12 69.1 1.54 - 1.05 Comparative Example 1 - - - - 64.5 - 0.56 0.65 Comparative Example 2 - - - - 68.2 - 0.74 0.75

As shown in Table 1, in the case of the aqueous paint prepared using the concomitant cellulose ether prepared according to Examples 1 to 7, the ICI viscosity was higher than that of the water-based paint prepared using HM-HEC according to Comparative Examples 1 and 2 Is improved.

As a result, it can be seen that the cellulose ether into which the functional group derived from the complex of a hydrophilic group has been introduced is enhanced in syneresis as compared with the cellulose ether hydrophobized by the simple hydrophobic group (C ₁₂ H ₂₅ -).

The water-based paint prepared by using the as-synthesized cellulose ether prepared according to the embodiment of the present invention has a high ICI viscosity and is therefore excellent in resistance to rubbing required in roller operation. As a result, according to the present invention, Aqueous paint can be provided.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Should be construed as being included in the scope of the present invention.

Claims (10)

As a cellulose ether containing a plurality of hydroxyl groups (-OH) in a molecule,
The cellulosic ether excellent in recycling (hereinafter, the cellulose ether before the functional group is substituted is referred to as "cellulose ether &quot;, and the cellulose ether before the substitution of the functional group is substituted with a functional group represented by the following formula The cellulose ether substituted with a functional group is referred to as "associative cellulose ether"):
Formula 1
AO- (C _n H _2n O) _m -
In Formula 1, A is a hydrophobic group selected from the group consisting of an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, an arylalkenyl group, a cycloaliphatic group, a perfluoroalkyl group, a carbosilyl group, Is 1-5 and m is 5-50. The method according to claim 1,
The hydrophobic group selected from the alkyl group, the alkenyl group, the perfluoroalkyl group and the carbosilyl group includes 1 to 40 carbon atoms, the cycloaliphatic group includes 3 to 40 carbon atoms, and the aryl group, arylalkyl group, Lt; / RTI &gt; wherein the hydrophobic group selected from the group consisting of alkyl, alkenyl and polycyclyl groups comprises 6 to 40 carbon atoms. The method according to claim 1,
And the substitution degree of the functional group is 0.4 to 2.0 wt%. The method according to claim 1,
The cellulose ether may be at least one selected from the group consisting of alkyl cellulose, hydroxyalkyl cellulose, hydroxyalkyl alkyl cellulose and alkylalkyl hydroxyalkyl cellulose. &Lt; RTI ID = 0.0 &gt; 1, &lt; / RTI &gt; The method of claim 1, wherein
Wherein the cellulose ether is hydroxyethyl cellulose having a hydroxyethyl group degree of substitution (MS) of 62 to 78 wt%. 6. A process for producing a crystalline cellulose ether according to any one of claims 1 to 5,
(1) reacting cellulose with an alkalizing agent to obtain an alkalized cellulose;
(2) reacting the alkalized cellulose with an etherifying agent to obtain a cellulose ether; And
(3) reacting the cellulose ether with an alkalizing agent, a coupling agent, and a compound represented by the following formula (2) to prepare a congeneric cellulose ether:
(2)
_{AO- (C n H 2n O)} m -H
In Formula 2, A is a hydrophobic group selected from the group consisting of an alkyl group, an aryl group, an arylalkyl group, an alkenyl group, an arylalkenyl group, a cycloaliphatic group, a perfluoroalkyl group, a carbosilyl group, Is 1-5 and m is 5-50. The method according to claim 6,
The cellulose ether prepared according to the step (2) is hydroxyalkylcellulose,
The step (2) comprises: reacting the alkalized cellulose with the first etherification agent to obtain the first hydroxyalkyl cellulose according to the step (1); And reacting the first hydroxyalkylcellulose with a second etherifying agent to obtain a second hydroxyalkylcellulose. &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt; 8. The method of claim 7,
And partially neutralizing the first hydroxyalkylcellulose with an acid. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt; The method according to claim 6,
The coupling agent may include one or more selected from the group consisting of methylene bromide (CH ₂ Br ₂ ), dichloroethane (C ₂ H ₄ Cl ₂ ), and diglycidyl ether By weight based on the total weight of the cellulose ether. A concomitant thickener comprising a conformational cellulose ether according to any one of claims 1 to 5.