JPS63182301A - Novel cellulose ether sodium salt and its manufacture - Google Patents

Abstract

PURPOSE:To produce an exceedingly salt-resistant cellulose ether sodium salt having a corrosion resistance to polyvalent metal ions, by etherifying cellulose by means of sulfoethylation followed by carbomethylation. CONSTITUTION:Cellulose is mercerized, and then etherified first by means of complete sulfoethylation followed by carbomethylation to to produce a cellulose ether sodium salt having a degree of substitution of the carboxymethy group of 0.2-1.0, degree of substitution of the sulfoethyl group of 0.4-1.0 and an exceedingly-salt-resistant coefficient K<=0.15, which is represented by the formula. In the formula, eta0 is the viscosity [mPa.s] of the above sample having a concentration of 2wt.% in a fresh water system: and eta1 is the viscosity [mPa.s] of the above sample having a concentration of 2wt.% in a 4wt.% aqueous CaCl2 solution system. The resulting cellulose ether sodium salt is most suitable as an additive for cementing in petroleum excavation as well as as an additive fir an aqueous solution or a slurry containing polyvalent metal salts, such as glazes, cosmetics etc.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application on Beams) The present invention relates to a novel cellulose ether sodium salt and a method for producing the same.

In recent years, it has been used as an additive for cementing in oil drilling, as well as for glazes, cosmetics, etc.

When added to an aqueous solution or slurry containing a metal salt, the physical properties of the solution are completely different from those of conventional monovalent metal salt resistance and gelation, that is, a system in which polyvalent metal ions exist. However, as a solution, it maintains the same viscosity as an aqueous solution.

There is also a strong need for a substance that provides an extremely excellent function of maintaining good dispersibility as a slurry.

(Conventional technology and its drawbacks) So far, the durability has been limited to -valent metal ion Na'',
It is mostly resistant to corrosion, and has a strong meaning of salt resistance.

In contrast to these properties, even though the system contains polyvalent metal ions such as Ca'', the viscosity decreases due to the lack of crosslinking or chelation with polyvalent ions and the lack of suppression of polymer chain spreading. Highly stable physical properties that do not cause deterioration, gelation, or precipitation should be distinguished as durability, which is completely different from resistance to monovalent metal ions.

Therefore, Kibatsu 1 refers to physical properties that far exceed conventional durability as ultra-salt resistance, and refers to materials whose ultra-salt resistance coefficient a:k, expressed by the following formula, corresponds to k≦0.15. It is evaluated as having an ultra-16J salt property.

1ηl−η. 1 Salt tolerance coefficient a: ni=□・・・・・・(1)η　0 In this case, the polyvalent metal is not limited to Ca but Mg.

M n , Z n , P b etc., and the C'a source is C
aC12 (7) as well as CaBr2, CaI2, Ca
(Now) 21 Ca (CHz Coo) 2 or the like may be used, and the salt water may be a mixture of these salts.

In formula (1), if ≦0.15, the difference in viscosity between the salt water system and the fresh water system is 15% or less, which means that there is almost no viscosity change in a harsh system such as the presence of Ca''.

On the other hand, when k > 0.15, η1 × η. When , the viscosity of the aqueous salt solution decreases due to insolubilization, etc., and η凰〉η. In this case, the aqueous salt solution undergoes gelation due to crosslinking with Ca''+, and the fluidity and uniformity of the solution are lost, making it almost impractical.

The evaluation of super salt tolerance by such a method is based on the following reasons.

That is, for a polymer that maintains its solubility even in a salt water system, 1 (
If the rate of viscosity change with respect to the concentration up to N11% is small, the CaCl2 concentration of 4! The viscosity change rate with respect to fresh water system viscosity tends to be the maximum when it takes a minimum value at In addition, it has good transparency, which is clearly due to its resistance to multivalent ions. Therefore, the value of k is 0.15
It is considered to have super salt resistance if the following conditions are met.

In other words, conventional cellulose yarn derivatives such as carboxymethylcellulose (CMC), carboxymethylhydroxyethylcellulose (CMHEC), sulfoethylcellulose (SEC), and sulfopropylcellulose (SPC),
Methylcellulose (MC), hydroxyethylcellulose (HEC).

The above-mentioned super salt tolerance cannot be found in hydroxypropylcellulose (HPC), methylhydroxyethylcellulose (MHEC), methylhydroxypropylcellulose (MHPC), and the like.

For example, if it is a non-ionic system, counter ions such as polyvalent metals may have little effect, but since the reaction system in the synthesis process is a gas-liquid solid phase reaction in an alkali, ether substituents and ether substituents Due to the uneven distribution of the degree of polymerization of the alkylene oxide that constitutes the group, when dissolved in an aqueous solution containing a polyvalent metal salt, the diffusion of the polymer chain is suppressed, resulting in a uniform increase in viscosity or gelation. tends to occur. MC, HEC, and RPC are typical examples.

In addition, CMC, which is a typical ionic cellulose derivative, has carboxymethyl groups (hereinafter abbreviated as 0M groups) that form crosslinks or chelates with polyvalent metal ions, resulting in gelation or insolubilization. Showa 57
Even with CMC introduced in No. 164101, which is said to have excellent salt resistance, super salt resistance is not recognized.

Carboxymethyl hydroxyethyl cellulose (CMHE) has a combination of ionic and nonionic ether substituents.
Cellulose mixed ethers such as C) can also be used with the above-mentioned HEC,
It only shows the same trend as CMC.

Furthermore, SEC, which has strong 7-ionic properties and is introduced as a Pauling mud water composition in JP-A No. 59-187078, exhibits an excellent ability to reduce water loss in systems containing polyvalent metal ions. When the degree of substitution of sulfoethyl 2& (hereinafter abbreviated as SE group) falls within this range, microgels etc. are formed, and ultra-salt resistance is not obtained.

Carboxymethyl sulfoalkyl cellulose (CMSAC), which is introduced as a drilling mud conditioner in Japanese Patent Publication No. 52-29267, is sulfofurkylated to compensate for the weak dissociation of the CM group of CMC in a salt water system. Ueba Since the etherification reaction is carried out in a system in which a ruboxymethylating agent (chloroacetic acids) and a sulfoalkylating agent (sodium 2-chloroethanesulfonate, etc.) are mixed simultaneously, excess water such as NaOH present in one reaction system is used. With respect to alkali oxides, terminal halide such as chloroacetic acid has a property that it is easier to replace with alkali cellulose than sodium chloroethanesulfonate, and CM conversion progresses preferentially.

The substitution reaction of SE groups with large steric hindrance proceeds locally,
This results in an extremely heterogeneous ether substitution reaction.

The obtained product does not have It11 salt properties, such as forming microgels even in an aqueous solution, becoming insolubilized, or exhibiting an extreme tendency to increase viscosity or gelation in an aqueous CaCl2 solution system.

(Problems to be Solved by the Invention) As described above, salt resistance against polyvalent metal ions is expected in cellulose-based materials. In other words, there is no substance with super salt resistance, and this is an important problem in industry.

(Means for Solving the Problems) In view of the above circumstances, the present inventors conducted intensive research in order to obtain a substance having ultra-salt resistance in accordance with the above-mentioned objective, and as a result, they arrived at the present invention.

That is, it is obtained by mercerizing cellulose and then etherifying it by a method that requires complete sulfoethylation and then carboxymethylation, and the degree of substitution of the CM group is 0. .2~1
．． The degree of substitution of 0 and SE groups is 0.4 to 1.0, and the ultra-salt resistance coefficient: k expressed by the following formula is k≦0.15, and even in a system where polyvalent ions exist, the aqueous solution is A novel cellulose ether sodium salt (CM
(abbreviated as SEC).

1　η　l　−η　01 Super salt tolerance coefficient: ni=□ η　0 The CMSEC of the present invention is manufactured by the following method.

Powdered pulp, which is commonly used as cellulose, is placed in a stirrer at a ratio of 3 to 10 times the weight of the pulp.

A mixed solvent of a lower alcohol having 3 or less carbon atoms such as isopropyl alcohol and water, and 2.0 to 5.0 mol of alkali hydroxide such as NaOH per anhydrous glucose residue are charged and mercerized. First, as the first etherification reaction, 0.5
~3.0 mol of sodium 2-chloroethanesulfonate is added and after complete sulfoethylation, 9 then as a second etherification reaction, 0.3~3.0 moles per anhydroglucose residue are added.
After the completion of the carboxymethylation reaction by adding 2.0 mol of chloroacetic acid, neutralize excess NaOH with acetic acid to give 80%
Purify with methanol several times and dry to obtain the desired CMSEC.

In other words, in the production method of cellulose mixed ether such as CMSEC, in order for the product to have ultra-salt resistance, the etherification reaction must be carried out uniformly, and in order to do so, the rigid crystal structure of cellulose must be destroyed to a greater extent. is necessary, and it is an essential condition that the SE version precedes the CM version. If the etherification reaction is carried out in this manner, the unsubstituted portion of the glucose residue that was not substituted due to the steric hindrance of the SE group will be effectively substituted by the subsequent CM conversion, resulting in a uniformly distributed substitution. A CMSEC with groups is obtained.

Among the etherification agents used, sulfoethylation agents are the best! There are compounds of ¥9, but sodium 2-chloroethanesulfonate in the present invention has high reactivity.
The etherifying agent may be a crude product that still contains sodium ethanedisulfonate or sodium llide, which is produced as a by-product in the manufacturing process. Sodium vinylsulfonate is easily hydrolyzed or synthesized in an alkali; Furthermore, alkyl sultones are toxic and are not preferred industrially.

In the case of other sodium haloalkylsulfonates, for example, sodium chloromethanesulfonate has low reactivity and requires severe reaction conditions, which has an unfavorable effect on physical properties. In addition, in the case of sodium haloalkylsulfonate having carbon tJ&3 or more, the hydrolysis reaction easily proceeds with alkali hydroxide such as NaOH, so it is unsuitable as an etherification agent.

In addition, the following method was followed for the property analysis and physical property evaluation of the obtained CMSEC (the same applies hereinafter).

(1) Degree of ether substitution (DS) The degree of ether substitution of the product of the present invention is determined by colloid titration method.
The SE degree and the CM degree are calculated from the a content and the sulfur content measured by the oxygen flask combustion method.

■Na content (N consumed by bound Na per 1g of sample)
/400 Amount of polyvinyl potassium sulfate aqueous solution (intestine 1)) Accurately weigh 0.3 to 0.5 g of the sample, dissolve it in water, and add 1150 g of the sample.
VK was added with excess N/200 methyl glycol chitosan aqueous solution 101, titrated with N/40G polyvinyl potassium sulfate aqueous solution using toluidine blue as an indicator, and the Na content: A (1) was calculated using the following formula. I asked for it.

A(■1)Tense □ X: Anhydrous sample Ikg S: To N00 Polyvinyl potassium sulfate aqueous solution titration 1 b Nibrafuku titration 11 ■ Sulfur content Accurately weigh 3 to 5 g of sample and pre-contain 10% peroxide Hydrogen water and S
After complete combustion in a combustion flask filled with hydrogen, the absorption liquid was ion-exchanged through a strongly acidic H-type ion exchange resin, 2-propatool 801 was added, and 1 g of 0.0 IN supersalt was added using trimethylene blue as an indicator. Sulfur content m:sc%) by titration with barium acid and the following calculation formula
I asked for

y: sample anhydride amount s: 0.01N barium perchlorate titration amount mlb blank titration amount intestine From A and S determined from ■ and ■, S using the following formula
The degree of E conversion and the degree of CM conversion were calculated.

Degree of SE = □ 3203-50S -32A 182S (0,4A/S) Degree of CM = □ 3203-505 -32A (2), after preparing a 2% solution and an 8% CaCl2 aqueous solution of the if salt-resistant sample, Divide the 4% aqueous solution into equal parts, add an equal weight of pure water to one, add an equal weight of 8% CaCl2 aqueous solution to the other, and separate the fresh water solution of the 2% sample and the fresh water solution of the 2% sample. A 4% by weight CaCl2 aqueous solution was prepared. After leaving each sample for a day and night, the viscosity was measured at 25° C. using a B-type viscometer, and the ultra-salt resistance coefficient k was determined based on the following formula.

1η biη. I Itli Salt resistance: □ η 0 (3) Transparency Place 2% of the sample in a cylindrical glass tube placed on a black and white lined board.
The solution was poured into the cylinder, and the height of the cylinder at which the border between black and white was no longer visible under a constant light source was defined as the transparency (Cm).

(Effects of the Invention) The CMSEC obtained according to the present invention has the following characteristics, that is, the viscosity of CMSEC and solutions of other cellulose derivatives produced by methods other than the present invention significantly change at a concentration of 4f1% by weight in a CaCl2 aqueous solution. On the other hand, the CMSEC of the present invention shows no change in viscosity and has extremely excellent physical properties such as ultra-salt resistance. It is ideal as an additive for aqueous solutions or slurries containing polyvalent metal salts.

(Example) An example of the present invention will be described below.

As comparative examples, CMC, SEC, CMHEC, and CMSEC performed by a method other than the present invention are also described.

Example 1 70 g of powder pulp was charged into a 31 volume Nigu, and 300 g of 2-propanol and 811.4 g of 40% NaOH aqueous solution were added.
Then, 48.8 g of sodium 2-chloroethanesulfonate was added and reacted for 60 minutes at 80° C. After cooling sufficiently, 25.7 g of 80% chloroacetic acid was added. ℃ for 60 minutes, and after completion, excess NaOH was neutralized with 50% acetic acid aqueous solution.
% methanol: After purifying several times and sufficiently desalting using 1000 g, the product was dried at 8° C. for 60 minutes to obtain CMSEC.

The obtained CMSEC has an SE degree of 0.55 (effective utilization rate of sodium 2-chloroethanesulfonate 84.6%)
, CM degree 0.34 (effective utilization rate of chloroacetic acid is SO
, t), viscosity of fresh water system (1@omPa*s and k
There was -0.08 te.

Example 2 Example 1: 811.4 g of 40% NaOH aqueous solution.

48.11 g of sodium 2-chloroethanesulfonate and 40% Ma instead of 7 g of @O% chloroacetic acid 2S
il (aqueous solution 108.0 g, crude sodium mono-chloroethanesulfonate 133.2 g (sodium 2-chloroethanesulfonate content 54% by weight) and 80% chloroacetic acid #
CMSEC was obtained in the same manner as in Example 1 except that 22.5 g was used.

Example 3 In Example 1, powdered cotton linter pulp was used instead of powdered pulp, and 46.8 g of sodium 2-chloroethanesulfonate and 25.7 g of 60% chloroacetic acid were added.
．． Sodium 2-chloroethanesulfonate 3 instead of
CMSEC was obtained in the same manner as in Example 1 except that 2.11 g and 40.8 g of 60% chloroacetic acid were used.

Example 4 In Example 1, the reaction system was previously set to a nitrogen atmosphere before charging the raw materials, powdered cotton linter pulp was used instead of powdered wood pulp, sodium 2-chloroethanesulfonate was added to 4s, sg, and 60% chloroacetic acid M! CMSEC was obtained in the same manner as in Example 1 except that 43.2 g of sodium 2-chloroethanesulfonate and 36.7 g of 80% chloroacetic acid were used instead of 25.7 g.

Comparative Example 1 In Example 1, 40% NaOH aqueous solution 8B, 40% NaOH aqueous solution 108. Using Og.

Except that the etherification reaction was carried out by simultaneously charging 50.4 g of sodium 2-chloroethanesulfonate and 57.8 g of 60% chloroacetic acid instead of 48.8 g of sodium 2-chloroethanesulfonate and 25.7 g of 60% chloroacetic acid M. is CMS E C by the same method as in Example 1.
I got it.

Comparative Example 2 In Example 1, 40% NaOH aqueous solution 44. l]g, 2
-Sodium 2-chloroethanesulfonate 181.0 in place of 8g of sodium chloroethanesulfonate 4B
SEC was obtained in the same manner as in Example 1, except that chloroacetic acid was used and chloroacetic acid was not used.

Comparative Example 3 Commercially available carboxymethyl hydroxyethyl cellulose (C
MHEC) Carboxymethyl group: D SO, 32Hydroxyethyl group: M S 0.81 Comparative Example 4 Commercially available carboxymethyl cellulose (CMC) D SO
,79 Comparative Example 5 Commercially available carboxymethyl cellulose (CMC) DS 1
．． 05 Comparative Example 6 ゛In Example 1, 40% NaOH aqueous solution 88.4
108.0 g of 40% NaOH aqueous solution was used instead of 108.0 g of 40% NaOH aqueous solution.

First, instead of 25.7 g of 6096 chloroacetic acid, 57.8 g of 6096 chloroacetic acid was charged to carry out the etherification reaction, and then 46.8 g of sodium 2-chloroethanesulfonate was added.
Sodium 2-chloroethanesulfonate 50 instead of g
．． CMSEC was obtained in the same manner as in Example 1 except that 4 g was charged and the etherification reaction was performed.

The properties of the substances obtained in the above Examples and Comparative Examples were
Shown in the table.

Table 1 Rich MS: Molar substitution degree of hydroxyethyl group 1^7 〇 Effective utilization rate of the etherification agent used to obtain the I group and the SE group α) The CMSEC of the present invention is It is clear that the value of k is 0.15 or less, that is, it has ultra-salt resistance, and the performance is significantly superior to the CMSEC of Comparative Examples 1 and 6 obtained using a known method.

Claims (2)

[Claims] (1) The degree of substitution of the carboxymethyl group is 0.2 to 1.0 and the degree of substitution of the sulfoethyl group is 0.4 to 1.0, and the super salt tolerance coefficient expressed by the following formula: k is k≦0 .15. Super salt resistance coefficient: k = |η_1−η_0|/η_0 [η_0: Clear water system viscosity of the above sample at 2% by weight [mPa・
s] η_1: Viscosity of 4 wt% CaCl_2 aqueous solution system of 2 wt% of the above sample [mPa・s]] (2) It is obtained by manufacturing with the essential conditions that the etherification reaction first involves complete sulfoethylation and then carboxymethylation, and the degree of substitution of the carboxymethyl group is 0.2 to 1. A novel cellulose ether sodium salt, characterized in that the degree of substitution of the sulfoethyl group is 0.4 to 1.0, and the super salt resistance coefficient k expressed by the following formula is k≦0.15. manufacturing method. Super salt resistance coefficient: k = |η_1−η_0|/η_0 [η_0: Clear water system viscosity of the above sample at 2% by weight [mPa・
s] η_1: Viscosity of 4 wt% CaCl_2 aqueous solution system of 2 wt% of the above sample [mPa・s]]