JPS5810408B2 - Kaishitsu Cellulo - Snow Seizou Hohou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing modified cellulose by adsorbing a water-soluble azo compound as a polymerization initiator and a polymerizable monomer onto cellulose and irradiating the adsorbed material with light.

More specifically, we eliminate the modification method of applying synthetic resins to cellulose products, and instead modify each cellulose cellulose with a synthetic resin in advance, and the cellulose products obtained from the modified cellulose are treated with conventional methods. It maintains the characteristics of cellulose products such as porosity and easy dyeability, while maintaining toughness, elasticity,
In order to impart properties such as thermal adhesion and water resistance, a water-soluble azo compound as a polymerization initiator and a polymerizable monomer are adsorbed onto cellulose and irradiated with light. The present invention relates to a technique for achieving the polymerization of added hexamer in a cellulose cellulose cellulose cellulose cellulose cell structure, and for combining cellulose and a synthetic resin within the structure thereof.

Generally, the water-soluble azo compound is evenly dissolved in the aqueous medium, so the polymerization initiation efficiency relative to the amount added is usually lower than that of the oil-soluble azo compound. However, the method of the present invention According to the study, the azo compound, which is a polymerization initiator, exists concentratedly in the places necessary for cellulose modification and acts.
Both the catalytic efficiency of the water-soluble azo compound and the reforming efficiency of the polymerizable monomer are greatly increased.

That is, the present inventors focused on the fact that water-soluble azo compounds have cationic properties due to quaternary nitrogen atoms in an aqueous medium, while celluloses have anionic properties, and the former was adsorbed to the latter. We have completed a new and useful technique for modifying cellulose by polymerizing monomers within the cellulose tissue very intensively through light irradiation.

In the case of thermal polymerization, it was difficult to increase production efficiency because there was a limit to the feed concentration, but using the method of the present invention, continuous polymerization is easily possible and productivity is improved. can be measured.

The water-soluble azo compound used in the present invention is (R1 in both formulas)
is alkyl or cycloalkyl having 1 to 6 carbon atoms, R
2 represents hydrogen, alkyl, cycloalkyl, aralkyl, or aryl, R3 represents hydrogen, and R2 and R3 may form a ring.

) or mineral acid salts thereof, or compounds selected from the group consisting of, for example, 2,2'-azobis(2-amidinopropane), 1,1'-azobis(1-amidino-1-cyclopropylethane) ), 2,2'-azobis(2-amidino-4-methylpentane), azobis-
N,N'-dimethyleneisobutyramidine, 2,2'-
Azobis (2-N-phenylaminoamidinopropane)
, ■, 1'-azobis(1-amidino-1-cyclohexylethane), 2,2'-azobis(1-imino-1
-ethylamino-2-methylpropane), 2,2'-azobis(1-allylamino-1-imino-2-methylbutane), 2,2'-azobis(1-imino-1-cyclohexylamino-2-cyclohexylpropane) ), 2,
2'-azobis(1-imino-1-laurylamino-2
-ethylpropane), 2,2'-azobis(1-imino-1-phenylamino-2,4-dimethylpentane),
2,2'-azobis(1-imino-1-benzylamino-2-cyclopentylpropane), 2,2'-azobis(1-imino-1-parachlorobenzylamino-2
-Methylbutane), 2,2'-azobis(2-cyclohexylpropionic acid hydrazide), 2,2'-azobisisobutyric acid hydrazide, and one or two compounds selected from the group of mineral salts thereof. It is a mixture of the above.

The photopolymerizable monomers used in the present invention include carbon, carbon double bonds, such as halogen atoms, carbonyl, cyanide, carboxy, ester, amide, ether, or allyl groups, and carbon double bonds or carbon triple bonds. For example, vinyl chloride, acrolein, acrylic acid and its salts or esters, acrylamide, and methacrylamide or derivatives thereof, acrylonitrile, methacrylonitrile, chlorobrene, vinyl ethyl ether,
It is one type or a mixture of two or more types, such as vinyl acetate and styrene, unsaturated polyester, or a mixture with a monomer compound that can be copolymerized with unsaturated polyester.

Used as a photoinitiator.

By appropriately selecting conditions such as the type and amount of the water-soluble Abu compound, the type and amount of the polymerizable monomer used, the wavelength of the light used, the irradiation time, and the temperature, PA-modified pulp can be produced according to each condition. Of course you can get it.

To obtain modified cellulose by light irradiation, 300 to 40
Exposure to any radiation source emitting a wavelength of 0 nm may be used, but
Since these water-soluble azo compounds have high photopolymerization activity, polymerization proceeds sufficiently even when exposed to sunlight.

Other suitable light sources include carbon arcs, mercury vapor lamps, fluorescent lamps, argon glow lamps, photographic lamps, and the like.

Since the polymerization initiator of the present invention can also be used as a thermal polymerization initiator, modified cellulose can be obtained by thermal polymerization without irradiation with light.

The aqueous medium for adsorbing the water-soluble azo compound onto cellulose may be any medium as long as the azo compound and cellulose can have cationic and anionic properties when dissolved or suspended. It may be of any composition.

For example, water alone or a mixture of water and one or more organic solvents that mix with water, such as alcohols, ketones, aldehydes, and dimethyl sulfoxide, can be used.

In order to adsorb a water-soluble azo compound onto cellulose, for example, the mineral acid salt of the azo compound and cellulose may be mixed and stirred in an aqueous medium, and then the solvent may be filtered off or distilled off. It is preferable to use the aqueous medium as it is as a solvent for the polymerization reaction.

After adding the monomer, the monomer is irradiated with light to achieve the desired polymerization reaction in the site where the polymerization initiator is concentrated, that is, within the cellulose structure, resulting in cellulose modified with a synthetic resin.

The resulting synthetic resin is integrated with the cellulose tissue, and does not separate from the cellulose even when sufficiently extracted with an organic solvent.

If the obtained modified cellulose is made into paper, for example, the paper will have new properties such as toughness, water resistance, elasticity, and heat-fusibility without losing the original advantages of paper.

As mentioned above, in the method of the present invention, polymers can be produced at a practical speed even by sunlight irradiation, and polymerization and curing can be completed in a very short time by ultraviolet irradiation, so polymers can be produced continuously. This has made it possible to produce modified cellulose at an extremely high cost on an industrial scale.

The present invention will be further explained with reference to Examples below.

The parts representing the amount of insole in the examples are parts by weight.

Example 1 5 parts bleached softwood pulp, 2,2'-azobis(2
-amidinopropane) hydrochloride 0.02 parts, water 100 parts,
2.55 parts of methyl methacrylate in a nitrogen atmosphere,
A 100W high-pressure mercury lamp was irradiated for 15 minutes from a distance of 10 crrL.

The reaction mixture was placed in 2000 parts of methyl alcohol;
After filtration and drying, 7.3 parts of modified cellulose is obtained.

This was further heated and refluxed with benzene to obtain 7.0 parts of residue.

Comparative Example 1 Light irradiation reaction and After post-treatment, the obtained residue was 5.1
There was almost no difference in weight from the pulp originally used in the section, and it was virtually impossible to obtain a modified pulp.

Comparative Example 2 4,4'-azobis(2-amidinopropane) hydrochloride was used as a water-soluble azo compound
The light irradiation reaction and post-treatment were carried out in the same manner as in Example 1 except that 0.02 part of 4-cyanopenctic acid) was used, but the residue obtained was 5.3 parts, which was virtually modified in this case as well. Couldn't get any pulp.

Example 2 30 parts of phosphoric acid-treated cellulose (trade name: Abecel P, manufactured by Abekawa Industries Co., Ltd.) was suspended in 400 parts of water, and 2,2'-
Add 0.5 part of azobis(2-amidino-4-methylpentane) hydrochloride and stir for 10 minutes.

Next, 25 parts of acrylonitrile and 1 part of polyether alcohol were added, and the mixture was irradiated with sunlight for 30 minutes at a reaction temperature of 10°C without any particular degassing in a Pyrex glass reaction tube.

57 parts of the solids collected by filtration were heated and extracted with 2000 parts of tetrahydrofuran to obtain 49 parts of polymethyl methacrylate-modified cellulose.

Example 3 Link - 100 parts, 2,2'-azobis(2-cyclohexylpropionic acid hydrazide) sulfate 1 part, water 150 parts
0 part was placed in a Pyrex glass reaction tube and irradiated with a 100W high-pressure mercury lamp from a distance of 10cm without any particular degassing.
After 10 minutes and 20 minutes, the ultraviolet absorption of 370 parts m of the supernatant liquid was measured, and the amount of catalyst adsorbed by the linter was calculated.

It was 0.8 parts after 10 minutes and 0.9 parts after 20 minutes.

Example 4 100 parts of water in a Pyrex glass reaction tube, 10 parts of the celluloses listed in Table 1, the water-soluble azo compounds listed in Table 2, and the monomers listed in Table 3 were added, and the mixture was heated at 10°C for 100 W.
The reaction solution was irradiated with a high-pressure mercury lamp from a distance of 10 cm for 15 minutes, poured into 2000 parts of methanol, and then filtered. This was further heated to reflux with 200 parts of benzene, filtered, and dried to obtain the amount shown in Table 4. Modified cellulose was obtained.

Claims (1)

[Scope of Claims] 1. A water-soluble ab compound that is a polymerization initiator in cellulose, that is, it has cationic properties due to a quaternary nitrogen atom in an aqueous medium (in both formulas, R1 is an alkyl having 1 to 6 carbon atoms or cycloalkyl, R2 represents hydrogen, alkyl, cycloalkyl, aralkyl, aryl, R3 represents hydrogen, and R2 and R3 may form a ring.) or a mineral acid salt thereof; A modified cellulose characterized by adding a compound selected from the group and a photopolymerizable monomer and irradiating it with light in an aqueous medium to polymerize the polymerizable monomer within the anionic cellulose structure. manufacturing method.