JP2005194324A - Manufacturing process of copolymer mixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber which has an excellent dyeability and contains a copolymer of a sulfonic acid group-containing vinyl monomer and a vinyl monomer copolymerizable with the monomer. <P>SOLUTION: The manufacturing process of the copolymer comprises solution-polymerizing 5-40 wt.% sulfonic acid group-containing vinyl monomer with 60-95 wt.% vinyl monomer copolymerizable with the monomer in a polymerization medium composed of a mixture of water and an organic solvent. In order to obtain a copolymer mixture containing a copolymer having a content of the sulfonic acid group-containing vinyl monomer component greater than the content ratio of the sulfonic acid group-containing vinyl monomer in the monomer mixture, the organic solvent is acetone, the weight ratio of water to the organic solvent is 10/90-50/50 and the amount of the polymerization medium used is 1-5 times by weight of the total amount of the monomers used. The fiber contains 3-30 wt.% of the copolymer mixture. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high content ratio of a sulfonic acid group-containing vinyl monomer component from a vinyl monomer copolymerizable with a sulfonic acid group-containing vinyl monomer rather than the charging ratio of the sulfonic acid group-containing vinyl monomer. The present invention relates to a method for producing a copolymer mixture containing a polymer and a fiber having excellent dyeability, which contains the copolymer mixture.

  Acrylic fibers and modacrylic fibers are used in pile products such as stuffed animals and clothing, hair decoration products such as wigs and hairpieces, and bedding products such as curtains and blankets. In order to improve the dyeability of these fibers, sulfonic acid group-containing vinyl monomers are widely used. It is known that the dyeability is an important basic property that increases the added value of the fiber, and generally, the more the sulfonic acid group-containing vinyl monomer component in the fiber, the better.

  As a method for producing these acrylic fibers and modacrylic fibers, a copolymer is prepared from a sulfonic acid group-containing vinyl monomer and a monomer copolymerizable therewith by a suspension polymerization method, an emulsion polymerization method, or a solution polymerization method. Thereafter, the fiber is generally obtained by a dry method or a wet spinning method. However, many problems occur when a large amount of the sulfonic acid group-containing vinyl monomer component is copolymerized to improve dyeability.

  In the emulsion polymerization and suspension polymerization methods, it is necessary to isolate the copolymer once after completion of the polymerization, but if the amount of the sulfonic acid group-containing vinyl monomer is increased, the solid-liquid separation at that time will be inferior in production. There is a tendency to deteriorate. For this reason, the amount of the sulfonic acid group-containing vinyl monomer that can be copolymerized is naturally limited. As a result, the dyeability of the fibers obtained from the copolymer is also naturally limited.

In the solution polymerization method, spinning is performed in a solution state after the completion of polymerization without isolating the copolymer. Therefore, the amount of the sulfonic acid group-containing vinyl monomer that can be copolymerized includes the amount of emulsion polymerization or suspension polymerization. It is difficult to be restricted. Actually, when N, N-dimethylformamide is used as a polymerization solvent for improving dyeability, a copolymer having a high content of a sulfonic acid group-containing vinyl monomer component prepared in advance is used as the main copolymer. A method of adding and polymerizing before the polymerization is proposed. (Patent Document 1) However, in this method, the copolymer having a high content of the sulfonic acid group-containing vinyl monomer component is all contained in the same content. Since a copolymer having the same composition is produced in large quantities at a time, it is a method suitable for a single-product mass production method, but has a disadvantage that it is not suitable for a multi-product small-quantity production method like today. Furthermore, N, N-dimethylformamide is a substance suspected of causing carcinogenicity and is not preferable in terms of safety. Other solvents used for solution polymerization of acrylic polymers include alcohols such as methanol, ethanol and isopropanol, ketones such as acetone and methyl ethyl ketone, N, N-dimethylacetamide, N, N-dimethylsulfoxide and the like. Nitrogen-containing low molecular weight compounds, aromatic hydrocarbons such as benzene, toluene and xylene, aliphatic hydrocarbons such as hexane, octane and cyclohexane, and acetates such as ethyl acetate and butyl acetate. In view of safety, ease of handling, and cost, acetone is preferable, but the solubility of the sulfonic acid group-containing vinyl monomer in acetone is very low, and when used in large quantities, sulfonic acid group-containing vinyl is used. The monomer is present in the polymerization solvent in an undissolved state. Under such an undissolved state, the sulfonic acid group-containing vinyl monomer does not participate in the copolymerization, and it is difficult to obtain a copolymer having a high content of the sulfonic acid group-containing vinyl monomer component. The amount of sulfonic acid group-containing vinyl monomer to be polymerized is very limited. As a result, the dyeability of the fibers obtained from the copolymer is also naturally limited.
JP-A 63-303111

  The present invention provides a sulfonic acid group-containing vinyl monomer and a copolymer of a vinyl monomer copolymerizable therewith by a solution polymerization method using a water / organic solvent mixed solvent as a polymerization solvent. An object of the present invention is to produce a copolymer mixture containing a copolymer having a high content of a group-containing vinyl monomer component and to provide a fiber with improved dyeability by containing the copolymer mixture. Is.

  As a result of intensive investigations to solve the above problems, by adjusting the water / organic solvent ratio and the amount of solvent at the time of polymerization, it contributes to dyeability even if a small amount of sulfonic acid group-containing vinyl monomer is used. It is possible to obtain a copolymer mixture containing a copolymer having a high content of sulfonic acid group-containing vinyl monomer component, and the dyeability of fibers containing this copolymer mixture is remarkably improved. And found the present invention.

  That is, a solution polymerization method using a copolymer of 5 to 40% by weight of a sulfonic acid group-containing vinyl monomer and 60 to 95% by weight of a vinyl monomer copolymerizable therewith with a water / organic solvent mixed solvent as a polymerization solvent. In order to produce a copolymer mixture containing a copolymer having a higher content of the sulfonic acid group-containing vinyl monomer component than the charge ratio of the sulfonic acid group-containing vinyl monomer, The co-weight is characterized in that the solvent is acetone and the weight ratio of water / organic solvent is 10/90 to 50/50, and the amount of polymerization solvent is 1 to 5 times the sum of the monomer weights charged. This is a fiber containing 3 to 30% by weight of the copolymer mixture in the fiber and the method for producing the coalescence mixture.

  According to the method of producing a copolymer of a vinyl monomer copolymerizable with the sulfonic acid group-containing vinyl monomer of the present invention by solution polymerization using a water / organic solvent mixed solvent as a polymerization solvent, It becomes possible to produce a copolymer mixture containing a copolymer having a high content of a sulfonic acid group-containing vinyl monomer component that is significant in dyeability from the monomer charge ratio. The copolymer mixture obtained by the production method of the present invention can be greatly improved in dyeability by adding a small amount to the spinning dope when producing acrylic fibers and modacrylic fibers.

  Examples of the sulfonic acid group-containing vinyl monomer used in the present invention include acrylamide-t-butylsulfonic acid or a salt thereof, styrenesulfonic acid or a salt thereof, methallylsulfonic acid or a salt thereof, allylsulfonic acid or a salt thereof. , Vinyl sulfonic acid or a salt thereof, or a mixture thereof. Preferable examples include sodium acrylamide-t-butylsulfonate and sodium methallylsulfonate. These monomers may be used alone or in a plurality of types at the same time, and 5 to 40% by weight, preferably 15 to 30% by weight, of the total monomers are used. When the amount of the monomer is less than 5% by weight, the resulting copolymer mixture is mixed with the spinning dope to make a fiber, and the dyeability is insufficient, and if it exceeds 40% by weight, it is not only disadvantageous in terms of cost. When the viscosity of the copolymer mixture solution is increased and the amount of precipitates is increased, the production efficiency tends to decrease in terms of heat removal from the polymerization heat generation.

  As the monomer copolymerizable with the sulfonic acid group-containing vinyl monomer, any monomer capable of ordinary radical polymerization may be used. For example, acrylic acid or its alkyl ester, methacrylic acid or its alkyl ester, acrylonitrile, methacrylo Nitriles such as nitriles, vinyl esters such as vinyl acetate and vinyl formate, aromatic vinyls such as styrene, vinyl halides such as vinyl chloride, vinyl bromide and vinyl fluoride, vinylidene chloride, vinylidene bromide, fluoride And vinylidene halides such as vinylidene, or mixtures thereof. Preferable examples include methyl acrylate, acrylonitrile, and mixtures thereof. These monomers are used in an amount other than the sulfonic acid group-containing vinyl monomer in all monomers, that is, 60 to 95% by weight, and particularly preferably 70 to 85% by weight.

  As the organic solvent for the polymerization solvent, acetone is used for the reasons described above. The weight ratio of water / acetone in the polymerization solvent used to obtain a high content copolymer of the sulfonic acid group-containing vinyl monomer component is larger than the target charge ratio of the sulfonic acid group-containing vinyl monomer. Although it varies depending on the amount of the sulfonic acid group-containing vinyl monomer, 10/90 to 50/50, particularly 20/80 to 40/60 is preferable. When the weight ratio is smaller than 10/90 (the ratio of water is low), the high content copolymer of the sulfonic acid group-containing vinyl monomer component is less than the target charge ratio of the sulfonic acid group-containing vinyl monomer. Although it is easy to obtain, the copolymer is easily separated in the solution, and it is impossible to continue the polymerization due to sedimentation at the bottom of the polymerization machine, and the productivity and handling of the copolymer solution are significantly lowered. When the ratio is larger than 50/50 (the ratio of water is high), the handling property of the solution is improved, but the sulfonic acid group-containing vinyl monomer component is higher than the target charge ratio of the sulfonic acid group-containing vinyl monomer. It is difficult to obtain a copolymer having a content rate, and as a result, the dyeability when the copolymer mixture is mixed into a fiber tends to decrease.

  The amount of the polymerization solvent is preferably 1 to 5 times by weight, particularly 1.5 to 3.0 times by weight of the total weight of charged monomers. When the amount of the polymerization solvent is less than 1 time, the viscosity of the copolymer solution becomes high, resulting in poor heat removal and the operation becomes difficult. In the case of more than 5 times, since the formation and precipitation of the high content copolymer of the sulfonic acid group-containing vinyl monomer component is not seen than the charging ratio of the sulfonic acid group-containing vinyl monomer, the present copolymer When the mixture is mixed into a fiber, the dyeability tends to decrease. In addition, the amount of the copolymer mixture obtained by one polymerization tends to decrease and the production efficiency tends to decrease.

  The polymerization initiator used in the present invention is not particularly limited as long as it is soluble in acetone, which is usually used in solution polymerization. For example, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2 , 4-dimethylvaleronitrile), azo initiators such as 2,2′-azobis (2-methylbutyronitrile), and organic peroxide initiators such as benzoyl peroxide and lauroyl peroxide. It is not limited to these.

  The polymerization temperature varies depending on the decomposition temperature of the initiator, the desired yield, the molecular weight of the copolymer, and the like, but is usually 30 to 90 ° C, particularly preferably 50 to 80 ° C.

  After completion of the polymerization reaction, the copolymer mixture solution is discharged from the polymerization machine and sent to the next process. If necessary, dilution by adding a solvent, concentration by removing the solvent, removal of unreacted monomers, coloring Addition of inhibitors and flame retardants will not cause any problems.

  For the fiber containing the copolymer mixture, the copolymer mixture is mixed in an arbitrary ratio according to the desired dyeability with a spinning stock solution in which a separately prepared main copolymer is dissolved. It is obtained by spinning by the method. The amount of the copolymer mixture in the fiber is preferably 3 to 30% by weight, particularly 4 to 10% by weight. If it is less than 3% by weight, sufficient dyeing performance cannot be obtained, and if it exceeds 30% by weight, the dyeing performance tends to be saturated.

  EXAMPLES Hereinafter, although this invention is demonstrated using an Example and a comparative example, this invention is not limited to these Examples. In the text,% and parts are based on weight.

Prior to the examples, definitions of analysis methods and the like will be described.
(Separation of precipitates)
The copolymer solution was treated with a centrifugal separator (Kubota Seisakusho 5100) at 1000 G for 2 minutes. The upper supernatant portion was separated as a uniform portion and the lower precipitation portion as a precipitation portion, and the respective copolymers were isolated by removing the polymerization solvent and drying.
(Sulphonic acid group-containing vinyl monomer component in the copolymer)
0.05 g of the dried copolymer is burned in a combustion apparatus (QF-02 manufactured by Dia Instruments), and the generated gas is absorbed in 100 ml of 0.3% hydrogen peroxide solution. The absorbing solution was analyzed by ion chromatography (Yokogawa IC-7000) to quantify the SO4 ion component. All SO4 ions were calculated as being derived from the sulfonic acid group-containing vinyl monomer.
(State of copolymer solution)
The state of the copolymer solution was determined visually.
(Fiber dye exhaustion rate)
A separately prepared copolymer of acrylonitrile 49% -vinyl chloride 51% is dissolved in acetone to a concentration of 30% to prepare a spinning dope A. A predetermined amount of the copolymer solution of the present invention and the spinning stock solution A were mixed to prepare a spinning stock solution B. The spinning dope B was spun into an aqueous acetone solution from a nozzle and solidified, and then washed with water, dried, stretched, and heat treated to obtain 3.3 dtex fiber. The fibers were dyed with malachite green 2.5% dye solution at 70 ° C. for 1 hour. The exhaust rate of the fiber was calculated from the residual liquid concentration after dyeing. The closer to 2.5%, the better the dyeability.

(Example 1)
A 5 L pressure vessel was charged with 1322 g of polymerization solvent (acetone 1120 g, water 202 g), sodium acrylamide-t-butylsulfonate 90 g, acrylonitrile 300 g, and methyl acrylate 210 g, and the temperature was raised to 65 ° C. 2,3′-Azobis (2,4-dimethylvaleronitrile) (3 g) was added to initiate polymerization. During the polymerization, while adding 6 g of 2,2′-azobis (2,4-dimethylvaleronitrile), the polymerization temperature was raised to 70 ° C. after 2 hours, the polymerization temperature was raised to 75 ° C. after 3 hours, and the polymerization was started for 5 hours. After the post-polymerization was completed, the copolymer solution was discharged after cooling to 40 ° C. The copolymer solution was clouded by precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was excellent at 0.9%. The amount of the sulfonic acid group-containing vinyl monomer component in the obtained copolymer was 37% of the precipitated portion and 12% of the uniform portion. The precipitation portion was a high content copolymer of the sulfonic acid group-containing vinyl monomer component with respect to 15% of the sulfonic acid group-containing vinyl monomer charge ratio.

(Example 2)
In Example 1, polymerization was performed in the same manner except that 240 g of acrylonitrile charged and 270 g of methyl acrylate were used. The copolymer solution was clouded by precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was excellent at 0.7%. The amount of the sulfonic acid group-containing vinyl monomer component in the obtained copolymer was 34% of the precipitated portion and 13% of the uniform portion. The precipitation portion was a high content copolymer of the sulfonic acid group-containing vinyl monomer component with respect to 15% of the sulfonic acid group-containing vinyl monomer charge ratio.

(Example 3)
In Example 1, the polymerization was carried out in the same manner except that 180 g of acrylonitrile charged and 330 g of methyl acrylate were charged. The copolymer solution was clouded by precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was excellent at 1.1%. The amount of the sulfonic acid group-containing vinyl monomer component in the obtained copolymer was 22% for the precipitated portion and 13% for the uniform portion. The precipitation portion was a high content copolymer of the sulfonic acid group-containing vinyl monomer component with respect to 15% of the sulfonic acid group-containing vinyl monomer charge ratio.

Example 4
A fiber was obtained in the same manner as in Example 3 except that the proportion of the copolymer of the present invention in the fiber was 20%. The dye exhaustion rate of the fiber mixed with this copolymer was excellent at 1.3%.

(Example 5)
In Example 1, polymerization was performed in the same manner except that the charged polymerization solvent was changed to 1400 g (acetone 1260 g, water 140 g). The copolymer solution was clouded by precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was as excellent as 1.4%. The amount of the sulfonic acid group-containing vinyl monomer component in the obtained copolymer was 34% of the precipitated portion and 8% of the uniform portion. The precipitation portion was a high content copolymer of the sulfonic acid group-containing vinyl monomer component with respect to 15% of the sulfonic acid group-containing vinyl monomer charge ratio.

(Example 6)
In Example 1, polymerization was carried out in the same manner except that the polymerization solvent charged was 1200 g (acetone 960 g, water 240 g). The copolymer solution was clouded by precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was as excellent as 1.4%. The amount of the sulfonic acid group-containing vinyl monomer component in the obtained copolymer was 35% of the precipitated portion and 7% of the uniform portion. The precipitation portion was a high content copolymer of the sulfonic acid group-containing vinyl monomer component with respect to 15% of the sulfonic acid group-containing vinyl monomer charge ratio.

(Example 7)
In Example 3, polymerization was carried out in the same manner except that 390 g of charged methyl acrylate and 30 g of sodium acrylamide-t-butylsulfonate were used. The copolymer solution was clouded by precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was excellent at 0.5%. The amount of the sulfonic acid group-containing vinyl monomer component in the obtained copolymer was 10% of the precipitated portion and 4% of the uniform portion. The precipitation portion was a high content copolymer of the sulfonic acid group-containing vinyl monomer component with respect to the sulfonic acid group-containing vinyl monomer charge ratio of 5%.

(Example 8)
In Example 3, polymerization was carried out in the same manner except that 300 g of charged methyl acrylate and 120 g of sodium acrylamide-t-butylsulfonate were used. The copolymer solution was clouded by precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was excellent at 2.4%. The amount of the sulfonic acid group-containing vinyl monomer component in the obtained copolymer was 42% of the precipitated portion and 17% of the uniform portion. The precipitated portion was a high content copolymer of the sulfonic acid group-containing vinyl monomer component with respect to the sulfonic acid group-containing vinyl monomer charge ratio of 20%.

(Comparative Example 1)
In Example 1, the polymerization was carried out in the same manner except that the polymerization solvent charged was 1400 g (acetone 560 g, water 840 g). The copolymer solution was transparent with no clouding due to precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was inferior at 0.1%.

(Comparative Example 2)
In Example 1, polymerization was carried out in the same manner except that the polymerization solvent charged was 1400 g (acetone 1330 g, water 70 g). In the copolymer solution, white turbidity due to precipitation was observed, but the precipitation of the precipitate became severe during the polymerization, making it impossible to continue the polymerization.

(Comparative Example 3)
In Example 1, polymerization was carried out in the same manner except that 114 g of acrylonitrile charged, 129 g of methyl acrylate, 43 g of sodium acrylamide-t-butylsulfonate, and 1714 g of polymerization solvent (acetone 1371 g, water 343 g) were used. The copolymer solution was transparent with no clouding due to precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was inferior at 0.1%.

(Comparative Example 4)
In Example 3, polymerization was carried out in the same manner except that 408 g of charged methyl acrylate and 12 g of sodium acrylamide-t-butylsulfonate were used. The copolymer solution was transparent with no clouding due to precipitation. The dye exhaustion rate of the fiber mixed with this copolymer was inferior at 0.1%.

  The production conditions for the copolymers of Examples and Comparative Examples, the properties of the obtained copolymer solutions, the composition of the copolymers, and the dyeing results of the fibers are shown in (Table 1).

Claims (6)

  A copolymer comprising 5 to 40% by weight of a sulfonic acid group-containing vinyl monomer and 60 to 95% by weight of a vinyl monomer copolymerizable therewith by a solution polymerization method using a water / organic solvent mixed solvent as a polymerization solvent. A copolymer mixture containing a copolymer having a high content of sulfonic acid group-containing vinyl monomer components from the charge ratio of the sulfonic acid group-containing vinyl monomer. A method for producing a coalescence mixture.   The copolymer having a higher content of the sulfonic acid group-containing vinyl monomer component than the charge ratio of the sulfonic acid group-containing vinyl monomer is in a state of being precipitated or separated in the polymerization solution. Production method.   The production method according to claim 1, wherein the organic solvent of the polymerization solvent is acetone and the weight ratio of water / organic solvent is 10/90 to 50/50.   The production method according to claim 1, wherein the polymerization solvent is charged in an amount of 1 to 5 times the total of the charged monomer weights.   A fiber comprising 3 to 30% by weight of the copolymer mixture produced by the production method according to claim 1 in the fiber.   The fiber according to claim 5, wherein the fiber according to claim 5 is an acrylic fiber or a modacrylic fiber.