JPH11302489A - Modifier for acrylic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a modifier which does not hurt human bodies and the environment and exhibits excellent modifying effects by incorporating 1- aminopyrrolidine (salt) and an alkali (alkaline earth) metal hydroxide as effective components. SOLUTION: There is provided a modifying agent which gives an acrylic resin hygroscopicity, pH buffering properties, antibacterial properties, flame retardancy and the like as excellent as those given by modification with hydrazine or a salt thereof. Nitrile groups in the acrylic resin react with 1- aminopyrrolidine or salts thereof to form amidine salts with concurrent hydrolysis of the nitrile groups to form carboxylic, salt-type carboxylic, amide groups or the like by an alkali (alkaline earth) metal hydroxide, which groups manifest hygroscopicity, pH buffering properties, antibacterial properties, flame retardancy and the like. The concentration of 1-aminopyrrolidine (salt) and alkali (alkaline earth) metal hydroxide contained in the aqueous solution of the modifier are preferably 5-80 wt.% and 10-60 wt.%, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an acrylic resin modifier. More specifically, the present invention relates to a novel acrylic resin modifier capable of imparting hygroscopicity, pH buffering property, antibacterial property, flame retardancy, and the like to an acrylonitrile-containing acrylic resin.

[0002]

2. Description of the Related Art Conventionally, in order to modify an acrylic resin containing acrylonitrile to impart hygroscopicity, pH buffering property, antibacterial property, flame retardancy, etc., a crosslinking agent is acted on to cause nitrile in the acrylic resin. After crosslinking the group, limiting the increase in nitrogen content due to the crosslinking to a specific range, then introducing a carboxyl group into a part of the nitrile group remaining by hydrolysis and an amide group into the remainder, and then adding an alkali metal salt or alkali. A method has been proposed in which the carboxyl group is converted into a salt form by adding a metal hydroxide or the like. And as a crosslinking agent, hydrazine hydrate, hydrazine sulfate, hydrazine hydrochloride,
At least one or two or more hydrazines such as hydrazine nitrate and hydrazine bromate and salts thereof are used (JP-A-5-132858, JP-A-5-132858).
-216730, JP-A-8-225610, JP-A-8-325938, JP-A-9-529
No. 13, JP-A-9-59872, etc.).

[0003]

However, the above-mentioned conventional method requires at least three steps to achieve the modification of the acrylic resin, and is not industrially satisfactory. Furthermore, hydrazine and its salts used as a cross-linking agent are not themselves very toxic, but
In the current situation where safety standards and work environments are being actively reviewed in factories that manufacture various products, safety to the human body and the environment is even higher than hydrazine and its salts, and is equal to or higher than these. An acrylic resin modifier having the above effects is desired. An object of the present invention is to provide a novel acrylic resin modifier which is highly safe for the human body and the environment and has an excellent modifying effect.

[0004]

The present invention provides (1) at least one compound selected from 1-aminopyrrolidine and a salt thereof.
And (2) an acrylic resin modifier containing at least one selected from an alkali metal hydroxide and an alkaline earth metal hydroxide as an active ingredient.

According to the present invention, a simple operation of allowing at least one selected from 1-aminopyrrolidine and a salt thereof to act on an acrylic resin,
Excellent hygroscopicity, pH buffering property, antibacterial property, flame retardancy, etc., equivalent to modification with hydrazine or a salt thereof can be imparted. Furthermore, 1-aminopyrrolidine and its salts have the advantage that they are very safe and do not adversely affect workers or working environments.

The reason why 1-aminopyrrolidine and a salt thereof having a different chemical structure from hydrazines bring about the same modification effect as hydrazines is not sufficiently clear.
Among the various active ingredients, the nitrile group in the acrylic resin and the 1-aminopyrrolidine of the above (1) react with the salt thereof to form an amidine salt, and the nitrile group is converted to the specific water of the above (2). Carboxyl group, salt type carboxyl group and amide group are generated by hydrolysis by oxide, and the generated amidine salt, salt type carboxyl group and amide group are hygroscopic, pH buffering, antibacterial, flame retardant, etc. Is considered to be expressed.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The acrylic resin modifier of the present invention comprises
It contains at least one selected from 1-aminopyrrolidine and a salt thereof as one of the active ingredients. 1-Aminopyrrolidine is a known compound and is used, for example, as an intermediate for the production of pharmaceuticals and agricultural chemicals. Further, as the salt of 1-aminopyrrolidine, for example, hydrochloride, sulfate,
Phosphates and the like can be mentioned.

Further, the acrylic resin modifier of the present invention contains, as another active ingredient, at least one selected from alkali metal hydroxides and alkaline earth metal hydroxides. Examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide, lithium hydroxide and the like. Examples of the alkaline earth metal hydroxide include calcium hydroxide, magnesium hydroxide, barium hydroxide and the like.

As the acrylic resin to be modified by the acrylic resin modifier of the present invention, any known acrylic resin containing acrylonitrile can be used. For example, acrylonitrile homopolymer, acrylonitrile and a monomer copolymerizable therewith And the like. The monomer copolymerizable with acrylonitrile is not particularly limited. For example, sulfonic acid compounds such as methallylsulfonic acid and p-styrenesulfonic acid and salts thereof, and (meth)
Acrylic acid, carboxylic acid group-containing compounds such as itaconic acid and salts thereof, vinyl halide, vinylidene halide,
(Meth) acrylic acid ester, acrylamide, styrene, vinyl acetate and the like can be mentioned. One or more of these monomers can be used. Although the acrylonitrile content in the acrylic resin is not particularly limited, it is usually 40% by weight or more, preferably 50% by weight or more.

The form of the acrylic resin is not particularly limited. For example, various forms such as fibers and particles may be used, but a fiber form is preferable. Fiber forms include, for example, short fibers, tows, yarns, knitted fabrics, nonwoven fabrics, and the like. Further, among the fiber forms, the acrylic resin molecules forming the fibers are sufficiently oriented and the dichroic ratio of Congo Red (hereinafter referred to as CR) is 0.4 or more, preferably 0.5.
By modifying the above with the modifier of the present invention,
Has sufficient fiber strength, moisture absorption, pH buffering, antibacterial,
It is possible to produce a modified acrylic fiber which is more excellent in flame retardancy and the like. The CR dichroic ratio is determined by Polymer Chemistry 23
(252) 193 (1966).

The modification of the acrylic resin in the present invention is usually carried out by bringing the acrylic resin modifier of the present invention into contact with the acrylic resin under heating. In a preferred embodiment, the acrylic resin is immersed in an aqueous solution of the modifier of the present invention and heated. At this time, the concentration of 1-aminopyrrolidine or a salt thereof contained in the aqueous solution of the modifier of the present invention is not particularly limited, and may be appropriately selected depending on the form or use of the acrylic resin to be modified. , Usually 5-8
It may be about 0% by weight, preferably about 10 to 50% by weight. The concentration of the alkali metal hydroxide and / or the alkaline earth metal hydroxide (hereinafter, these are collectively referred to as “hydroxide” unless otherwise specified) is not particularly limited.
-The amount of aminopyrrolidine or a salt thereof, the type of hydroxide used, the type and the type of acrylic resin to be modified may be appropriately selected from a wide range depending on the intended use, but usually 10 to 60% by weight, Preferably, it may be about 30 to 40% by weight. Modification by the acrylic resin modifier of the present invention is usually about 50 to 130 ° C, preferably 80 to 100 ° C.
The reaction is carried out at a temperature of about ° C, and is usually completed in about 0.5 to 8 hours, preferably about 1 to 4 hours.

In the present invention, the acrylic resin may be heat-treated in an aqueous solution of 1-aminopyrrolidine or a salt thereof, and then heat-treated in an aqueous solution of a hydroxide. Here, the concentration of 1-aminopyrrolidine or a salt thereof, a hydroxide, a treatment temperature, a treatment time, and the like may be the same as those described above. By the above modification, an acrylic resin having excellent hygroscopicity, pH buffering property, antibacterial property, flame retardancy and the like can be obtained. The acrylic resin can be used for practically all uses known as uses of the acrylic resin, and examples thereof include various clothing materials, paint components, resin additives, and adsorbents for malodorous components such as aldehydes. it can.

[0013]

The present invention will be described more specifically with reference to the following examples and comparative examples. In the following, “parts” and “%” refer to “parts by weight” and “% by weight”, respectively.
Means Example 1 10 parts of a copolymer consisting of 90% of acrylonitrile and 10% of methyl acrylate (intrinsic viscosity in dimethylformamide at 30 ° C. = 1.2) was treated with a 48% aqueous solution of rodin soda 9
The spinning stock solution dissolved in 0 parts is spun and drawn (total draw ratio =
10) After that, drying was performed in an atmosphere of dry bulb / wet bulb = 120 ° C./60° C., and then relaxation treatment was performed under high pressure steam at 125 ° C. (process shrinkage 27%) to obtain a single fiber fineness of 1.0 denier. A raw fiber (CR dichroic ratio = 0.56) was produced. 10 g of the raw material fiber obtained was subjected to a 1-aminopyrrolidine concentration of 3
After boiling for 3 hours in 1 liter of an aqueous solution having a concentration of 5% and a concentration of sodium hydroxide of 10%, the mixture was washed with water to produce a modified acrylic fiber.

Comparative Example 1 10 g of a raw fiber produced in the same manner as in Example 1 was modified according to the method described in JP-A-8-325938. That is, 10 g of raw material fiber is added to a 13% hydrazine aqueous solution 1
After boiling for 3 hours in 1 liter of a 10% aqueous sodium hydroxide solution for 2 hours, acid-treating with hydrochloric acid, treating again with sodium hydroxide and washing with water.
It was treated with 1 liter of (OH) ₂ aqueous solution at 60 ° C. for 5 hours and washed with water to produce a modified acrylic fiber.

[0015] The modified acrylic fiber obtained in Example 1 and Comparative Example 1 was tested for moisture absorption and
The pH buffer capacity, sterilization rate and flame retardancy were examined. Table 1 shows the results
Shown in (1) Moisture Absorption Approximately 5.0 g of the modified acrylic fiber was dried at 105 ° C. for 16 hours, and the weight [(W1) g] was measured. Next, this was put in a thermo-hygrostat at a temperature of 20 ° C. and a relative humidity of 65%,
After standing for 4 hours, the weight [(W2) g] was measured. From the above results, the moisture absorption was calculated according to the following equation. Moisture absorption (%) = [(W2−W1) / W1] × 100

(2) pH buffer capacity (μeq / g) About 0.4 g of a sufficiently dried modified acrylic fiber was precisely weighed [(X) g], and 200 ml of water was added thereto.
Hydrochloric acid or 0.1N aqueous sodium hydroxide solution is added dropwise, and the consumed amount of hydrochloric acid or aqueous sodium hydroxide solution until the pH becomes 5.0 in the case of hydrochloric acid or 7.0 in the case of aqueous sodium hydroxide solution. [(Y) cc] was determined, and the buffering capacity against acid or alkali was calculated by the following equation. pH buffer capacity (μeq / g) = 1000Y / X

(3) Antibacterial property Test strain: Staphylococcus aureus
IFO 12732) Test method: According to the method specified by the Textile Sanitary Processing Council (SEK), a bouillon suspension of the test bacterium is poured on a sterilized sample cloth and cultured in a closed container at 37 ° C for 18 hours. The number of bacteria was measured, and the difference was calculated as the difference between the number of bacteria B of the standard cloth and the number of bacteria C of the sample with respect to the number of inoculated A. Increase / decrease value = log C-log A Difference value = (log B−log A) − (log C−log A) (4) Flame Retardancy (LOI) The flame retardancy (LOI) was measured according to the method for measuring the lowest oxygen index of JIS-7201.

[0018]

[Table 1]

From Table 1, it is clear that the acrylic resin modifier of the present invention has the same effect as hydrazine.

According to the present invention, it is possible to provide a novel acrylic resin modifier which is highly safe for the human body and the environment and has an excellent modifying effect.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akihiro Nabeshima 463 Kagasuno, Kawauchi-machi, Tokushima City, Tokushima Prefecture Inside the Otsuka Chemical Co., Ltd. Inside Tokushima Factory

Claims (1)

[Claims] 1. An active ingredient comprising (1) at least one selected from 1-aminopyrrolidine and a salt thereof, and (2) at least one selected from an alkali metal hydroxide and an alkaline earth metal hydroxide. Acrylic resin modifier.