JPS61282477A - Modification of synthetic fiber - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for uniformly and economically modifying 9 synthetic fibers with high reaction efficiency.

(Prior art) Conventionally, as a method for efficiently graft polymerizing a hydrophilic vinyl monomer onto a hydrophobic synthetic fiber, Japanese Patent Publication No. 59-5126
No. 51-87592, etc.

The former method relates to a monomer composition for a two-step in-bath method in which graft polymerization is performed after activation pretreatment, but it is uneconomical because it requires two steps: an activation pretreatment step and a graft polymerization step. Furthermore, the latter relates to a one-stage method in a bath that does not require pre-activation treatment, but the immersion heating method in a bath leaves a large amount of unreacted monomer and the grafting reaction efficiency is not high, and a large amount of homogeneous material is generated in the bath. Problems arise in that the polymer contaminates processing machines and even wastewater.

Therefore, it is difficult to say that it is economical overall.

(Means for Solving the Problems) (1) In a method of modifying synthetic fibers by graft polymerization with a hydrophilic vinyl monomer, a graft polymerization initiator, a hydrophilic vinyl monomer, and a water-soluble polymer having an sp value of 95 or more are used. 1. A method for modifying synthetic fibers, which comprises applying an aqueous mixture of a synthetic organic solvent to the synthetic fibers and then subjecting the synthetic fibers to a heat treatment.

(2) The method for modifying synthetic fibers according to claim 1, wherein the heating means uses microwaves or a combination of steam and microwaves.

(Description of Means) Synthetic fibers in the present invention are fibers made of ordinary fiber-forming synthetic resins, including, for example, polyalkylene terephthalate fibers, polyamide fibers, polyolefin fibers, polyacrylonitrile fibers, etc. Furthermore, fibers made of these modified polymers, a mixture thereof, or a combination of these with natural fibers were used. It includes mixed fibers in various forms. The form of these synthetic fibers may be any type, such as tow, single-thread fabric, or non-woven fabric. What is the sp value (strubility parameter value) of various compounds?9For example, fiber processing v01゜26m6C19
As described in 74), it is one of the parameters indicating the solubility characteristics of a solvent.

The SP value is indicated as l, and is generally calculated as the square root of the cohesive energy density, but for polar molecules, it can be calculated from the heat of vaporization, boiling point, surface tension, solubility, etc. There is.

The water-soluble organic solvent with an sp value of 95 or more in the present invention is generally used as an organic solvent or a chemical. For example, alcohols include methanol, ethanol,
This includes monohydric alcohols such as propatool and polyhydric alcohols such as ethylene glycol, propylene glycol, and glycerin. An example of a ketone is acetone.

Includes acetonitrile acetone, etc.

Examples of amines include pyridine and monoethanolamine. As for ethers, diethylene glycol monoethyl ether.

Includes diethylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol ether ether, etc.

Examples of acid amides include N,N-dimethylformamide, N,N-dimethylacetamide, and the like. Examples of acids include formic acid.

Contains acetic acid, propionic acid, etc. Examples of oxyacids include, but are not limited to, lactic acid. These water-soluble organic solvents with an SP value of 95 or more are added for the purpose of stabilizing the solution, and they may be used alone, in combination of two or more, or in combination with a surfactant. .

Among these, the amount required for chemotaxis is particularly low.

Acetic acid, dimethylpolamide,
And it can be said that the use of lactic acid is the most preferable.

With water-soluble organic solvents with an sp value of less than 95, such as diacetone alcohol, or poorly water-soluble organic solvents with an sp value of 95 or more, such as methyl formate, it is difficult to obtain a stable aqueous mixture, and the layer forms in a short time. Separation occurs and a uniform reaction cannot be performed.

The hydrophilic vinyl monomer referred to in the present invention is usually applied to graft polymerization. It is a compound containing at least one polymerizable unsaturated group and can be applied regardless of its molecular weight.

Examples of such monomers include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, and itaconic acid; unsaturated amides such as acrylamide, methacrylamide, N-methylolacrylamide, and vinylpyrrolidone; Examples include various unsaturated compounds such as unsaturated phosphorus compounds such as phosphonic acid, and unsaturated aromatic compounds such as vinyl sulfonic acid and styrene sulfonic acid. In the present invention, derivatives of these monomers are also applicable.

Examples of such derivative compounds include various compounds obtained by adding ethylene oxide to the above monomers, such as polyethylene glycol monoacrylate, polyethylene glycol dimethacrylate, and acrylamide ethylene oxide adducts, but are limited to these monomers. It is not necessary, and in short, any compound containing a polymerizable unsaturated group can be used as the monomer of the present invention. Such monomers can be used alone or in combination of two or more.

Examples of the graft polymerization initiator in the present invention include:
Radical polymerization initiators include, but are not limited to, benzoyl peroxide and azobisisobutyronitrile.

Although the present invention does not require the addition of a fiber swelling agent, it is possible to add a fiber swelling agent depending on the purpose.
As such fiber swelling agents, compounds such as chlorobenzene-based, phenol-based, benzoic acid-based, etc. can be applied.

The present invention comprises a hydrophilic vinyl monomer, a graft polymerization initiator,
After keeping the aqueous mixture containing a fiber swelling agent and the like as necessary in an extremely uniform and stable state, the aqueous mixture is applied to the synthetic fibers by padding.

Graft polymerization is carried out in one processing step by heat treatment, in order to bring the aqueous mixture into an extremely uniform and stable state.

It is characterized by the addition of a water-soluble organic solvent with an sp value of 95 or more.

The hydrophilic vinyl monomer concentration of the aqueous mixture is 5 to 70%.
It is preferable to adjust it within the range of . Below this range, the stability of the solution is extremely reduced and the grafting efficiency is also reduced.

Moreover, exceeding this range leads to a decrease in grafting efficiency, which is thought to be due to a decrease in the carrier effect of water. The amount of water-soluble organic solvent added with an sp value of 95 or more is a monomer concentration of 9 and a polymerization initiator concentration.

It varies depending on the fiber swelling agent concentration, the temperature of the liquid, and the type of water-soluble organic solvent with an sp value of 95 or more, and is difficult to determine, but the important thing is the amount that will result in a uniform and extremely stable aqueous mixture.

The concentration of the graft polymerization initiator is preferably in the range of 0.1% to 6.0%, and if it deviates from this range, homopoly ff - will occur frequently and the graft polymerization efficiency will decrease.

Further, as mentioned above, the fiber swelling agent is not particularly required, but when added, the concentration is preferably 5% or less as a pure product. If this value is exceeded, the graft polymerization efficiency decreases.

The order in which these hydrophilic vinyl monomers and graft polymerization initiators are added is not particularly limited;
It is preferable to add water and a water-soluble organic solvent having an sp value of 95 or more.

The aqueous mixture containing the monomer thus prepared is applied in a required amount to synthetic fibers by a padding method or the like. Other application methods include spraying, coating, and squeezing with a centrifugal dehydrator after immersion, but these can be selected as appropriate depending on the form of the object to be treated, the required amount of application, etc. An aqueous mixed solution containing such monomers is applied to the treated material, which is then transferred to a heating system. When an object to be processed that has been transferred to a heating system is left to stand still for heat treatment, the processing liquid normally moves downward due to its own weight, and preferably the object to be processed is heated to an extent that does not cause liquid movement due to centrifugal force. It is preferable to keep the liquid in a state where there is little liquid movement, such as by rotating it.

As the heating means, a normal heating mechanism can be applied.

Preferably, heating by microwaves or a combination of steam and microwaves may be selected from the viewpoint of temperature increase rate and ease of control.

When using this heating method, the temperature increase rate depends on the frequency, the type and amount of dielectric material, the movement speed of the object to be treated, etc.
The maximum temperature is different, but by adjusting each,
The heating rate and maximum temperature can be regulated.

Although it varies somewhat depending on the type of graft polymerization initiator and the type of monomer, it is usually 80°C or higher, preferably 100°C or higher,
Temperature conditions of up to 180° C. are applied.

(Example) Example 1 0.5 g of organic peroxide (NIPER MT-80 manufactured by NOF Co., Ltd.) as a graft polymerization initiator, 30 g of methacrylic acid as a hydrophilic vinyl monomer, and a water-soluble organic solvent with an SP value of 95 or more. Add 5 g of acetic acid and dilute with water to make 10
0 g of an aqueous mixed solution was prepared.

Next, a polyethylene terephthalate processed yarn fabric (Toshi Seisu 2525), which had been subjected to intermediate scouring, was soaked in the aqueous mixture, squeezed with a mangle, wound into a roll, and then sealed with a vinylidene chloride film. The pick-up rate at this time was 70% of the weight of the processed yarn fabric. Next, the fabric was placed in a microwave treatment device (Aboropet, manufactured by City) and heated and irradiated with 100°C steam and microwave for 5 minutes.

After drying using the hot water method, the weight increase rate relative to the initial processed yarn fabric weight was determined.

The reaction efficiency of the monomer corresponding to the weight increase rate was calculated as follows, taking the pickup rate into consideration.

The results are shown in Table 1.

Monomer reaction efficiency - Grafting efficiency Grafting efficiency (%) - [Weight increase rate 20, 7 x monomer concentration) xloo [In the formula 1 Weight increase rate: weight %, monomer concentration: weight fraction] Comparative example 1 Example 1 In place of dimethylformamide, a water-soluble organic solvent with an sp value of 95 or more, 40% diacetone alcohol (a water-soluble organic solvent) with an sp value of 92 was added.

In Example 1, a uniform and stable aqueous mixture was obtained, but
In Comparative Example 1, the mixed liquid was separated into two layers.

It was unsuitable as a pad liquid.

Comparative Example 2 Graft polymerization initiator (Niper MT-80 manufactured by NOF Corporation)
) 2g, swelling agent for polyethylene terephthalate fibers: 10g monochlorobenzene, 5g emulsifier (Ninoigen EA160 manufactured by Nihon Yushi) 1:1 (by weight) mixture of acrylic acid and methacrylic acid 2 as hydrophilic vinyl monomer.
0g was diluted with water and 1000g/bound. Next, a log of polyethylene terephthalate processed yarn fabric (+2525 manufactured by Toshi Co., Ltd.), which had been finished with the scouring intermediate set, was immersed in 300 d of this solution and heat-treated at 100° C. for 60 minutes. Next, the hot water method,
After drying, determine the weight increase rate with respect to the initial processed yarn fabric9
Grafting efficiency was determined using the following formula.

The results are shown in Table 1.

[In the formula: weight increase rate: weight ratio]

Table 1 As is clear from Table 1, the grafting efficiency of the fabric obtained by graft polymerization in one step using the aqueous mixture obtained in Example 1 was high; The grafting efficiency in Comparative Example 3, which was subjected to polymerization treatment, was low. Also, Comparative Example 1 in which a water-soluble organic solvent with an sp value of less than 95 was used instead of a water-soluble organic solvent with an sp value of 95 or more. In Comparative Example 2 using an organic solvent with an SP value of 95 or more, a stable aqueous mixture was not formed, and one-step graft polymerization treatment could not be performed.

(Effects of the Invention) The present invention can uniformly and extremely economically modify 9 synthetic fibers with high reaction efficiency.

Claims (2)

[Claims] (1) In a method of modifying synthetic fibers by graft polymerization with a hydrophilic vinyl monomer, a graft polymerization initiator, a hydrophilic vinyl monomer, and a water-soluble organic solvent having a Sol Utility Parameter (SP) value of 9.5 or more are used. 1. A method for modifying synthetic fibers, which comprises applying an aqueous mixture consisting of the following to the synthetic fibers and then heat-treating the synthetic fibers. (2) The method for modifying synthetic fibers according to claim 1, wherein the heating means is microwaves or a combination of steam and microwaves.