JPS603095B2 - Method for dissolving high-grade α-olefin modified polyvinyl alcohol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for dissolving polyvinyl alcohol modified with a higher Q-olefin in water.

Higher Q-olefin modified polyvinyl alcohol obtained by saponifying 50 mol% or more of the vinylester component of a Q-olefin-vinyl ester copolymer with a Q-olefin content of 5 or more carbon atoms from 0.5 to 15 mol% is anhydrous. However, since it is insoluble in water and general organic solvents, it is difficult to prepare a solution of the polymer, and it is difficult to bond or mold the polymer in a solution state. It cannot be used for purposes such as coating or casting, and it is also not easy to efficiently clean and remove the polymer that adheres to reaction vessels and piping during the production of the polymer.

The above-mentioned high-grade Q-olefin-modified polyvinyl alcohol does not dissolve or swell in non-polar solvents such as benzene, hexane, gasoline, and oil, but swells considerably in polar organic solvents such as methanol, chloroform, and pyridine, and in water. It has the property that it dissolves but does not dissolve at all.

The present inventors believed that if the above-mentioned higher Q-olefin-modified polyvinyl alcohol could be made to dissolve in inorganic or organic solvents, especially water, its application range would be extremely wide-ranging, and as a result of intensive research, the above-mentioned higher Q-olefin-modified polyvinyl alcohol The present invention was completed based on the discovery that polyvinyl alcohol can be easily dissolved in water by bringing it into contact with water in the presence of an anionic surfactant.

As the Q-olefin component of the higher Q-olefin modified polyvinyl alcohol used in the present invention, one having 5 or more carbon atoms is used.

There is no particular upper limit to the upper limit, but if the carbon number exceeds 30, the degree of polymerization will decrease and practicality will be diminished, so it is usually appropriate to use a polymer with a carbon number of at least 30. When the number of carbon atoms is less than 5, there is a disadvantage that the polymerization operation must be carried out under pressure, and the properties of the polymer are significantly different from those when the number of carbon atoms is 5 or more, so they are excluded from the scope of the present invention. The copolymerization ratio of such higher Q-olefin needs to be within the range of 0.5 to 15 mol%, and if it is 0.5 mol%, it is almost water-soluble or water-removalable, so the present invention On the other hand, if the amount exceeds 15 mol %, the degree of polymerization of the polymer decreases significantly, resulting in poor backdoor properties. Specifically, the higher Q-olefins mentioned above include Q-bentene, Q-hexene, o-heptene, Q-octene, Q-nonene, Q-decene, Q-dodecene, Q-tridecene, Q-tetradecene, Q-bentadecene, Q -hexadecene, Q-octadecene, Q-eicosene, etc., and these may be used alone or in combination of two or more.

Examples of the vinyl ester component include vinyl formate, vinyl acetate, vinyl propionate, vinyl stearate, and vinyl benzoate, but vinyl acetate is particularly useful in practice.

When copolymerizing the higher Q-olefin and vinylester as described above, a small amount of a third component copolymerizable with these may be present. The degree of saponification of the vinyl ester unit of the high Q-olefin-vinyl ester copolymer should be at least 50 mol%, and if the degree of saponification is less than that, there will be too much anionic surfactant to make it water-soluble. This is not appropriate because it requires

Various known anionic surfactants may be used as the anionic surfactant used to make the saponified high Q-olefin-vinyl ester copolymer, ie, the high Q-olefin modified polypinyl alcohol, soluble in water. Although any of them can be used, the following anionic surfactants are most effective in improving solubility.
301 alkyl sulfates, such as sodium lauryl sulfate, ammonium lauryl sulfate, etc. [2'alkyl sulfonate, e.g. alkyl (12-16 carbon atoms)]
Secondary sodium sulfonate, etc.

'3' Alkylbenzenesulfonate, such as sodium laurylbenzenesulfonate.

'41 dialkyl sulfosuccinates, such as dioctyl sodium sulfosuccinate.

[51 fatty acid alkali salts, such as sodium oleate,
Semi-hardened beef tallow sodium soap, potassium oleate, hando-cured beef tallow potassium soap, castor oil potassium soap, sodium stearate, potassium stearate, etc.

Other anionic surfactants, such as middle-higher fatty acid alkylolamide sulfate and higher fatty acid alkylolamide sulfonate, are slightly less effective than the anionic surfactants ``1'' to ``5'' above. Alkyl ether sulfates, polyoxyethylene alkyl phenyl ether sulfates, alkyl phosphate salts, and alkylnaphthalene sulfonates have even smaller effects.

Various nonionic surfactants and cationic surfactants/active agents have no solubility-imparting effect.

However, there is no particular problem in using a nonionic surfactant together with the above-mentioned anionic surfactant. The amount of the anionic surfactant used to solubilize the higher Q-olefin modified polyvinyl alcohol in water should be 2 parts by weight or more, especially 5 parts by weight or more based on 10 parts by weight of the higher Q-olefin modified polyvinyl alcohol. preferable. The upper limit is not particularly limited and can be up to several tens of parts by weight, but since there are economical and usage restrictions when using too much, it is usually kept at about 200 parts by weight at most. Several percent of high Q-olefin modified polyvinyl alcohol can be obtained by using anionic surfactant.
Aqueous solutions with concentrations ranging from 10% to several 10% can be prepared.

Although heating is not necessarily required for dissolution, dissolution proceeds quickly and a more highly concentrated aqueous solution can be prepared. Generally, the dissolution is carried out by bringing the higher Q-olefin-modified polyvinyl alcohol, anionic surfactant and water into contact with each other by mixing or leaving them to stand. In addition, a mode in which a molded product of high-grade olefin-modified polyvinyl alcohol molded together with an anionic surfactant or a pulverized product thereof is brought into contact with water is also adopted. The method of the invention includes: o Adhesives, coatings, paints.

o Binder for plaster, cement, etc., binder for manufacturing inorganic or organic fiberboard, binder for manufacturing inorganic filler board.

o Pigment binder for paper, sizing agent or coating agent for paper.

o Warp sizing agent, fiber or textile product processing agent.

o Dispersion or emulsion stabilizer.

o Raw solution for manufacturing films, fibers, composite fibers, semipermeable membranes, etc.

o For production of phenolic resins or amino resins. o pack agent,
For poultices and hand cleaners.

o For adding detergent. o For post-denaturation such as formalization and imparting photosensitivity.

oHigher Q-Purpose of dissolving or cleaning areas to which olefin-modified polyvinyl alcohol has adhered. o Selective elution of the former resin from a film or other molded product or composite molded product made by blending higher Q-olefin-modified polyvinyl alcohol with another resin.

It can be applied to etc.

Next, the method of the present invention will be further explained with reference to Examples.

Hereinafter, the term "parts" refers to parts by weight. Example 1 5 parts of Q-octene modified polyvinyl alcohol (Q-octene amount 8.0 mol%, total saponification degree of vinyl acetate component mol%) and 1 part of sodium lauryl sulfate were added to 10 parts of water. When the solution was stirred at about 5 psi, an almost transparent aqueous solution with low viscosity was obtained.

Examples 2 to 4 In place of sodium lauryl sulfate, sodium dioctyl sulfosuccinate (Example 2), sodium laualylbenzenesulfonate (Example 3), sodium alkyl secondary sulfonate having 14 carbon atoms (Example 4), Sodium stearate (Example 5)
A dissolution test was carried out in the same manner as in Example 1, except that the solution was used, and a homogeneous solution was obtained in each case.

Examples 5 to 7 Types of higher Q-olefin modified polypinyl alcohol,
Dissolution tests were conducted using various types of anionic surfactants.

Note that the melting temperature was 60 to 70°C. Example 5 Q-dodecene modified polyvinyl alcohol (Q-dodecene content 65 mol%, total saponification degree of vinyl acetate component mol%)
7 parts dioctyl sodium sulfosuccinate 1 part water
10 base parts Uniformly dissolved Example 6 Q-octadecene modified polyvinyl alcohol (Q-octadecene content 4.5 mol%, degree of saponification of vinyl acetate component 96 mol%) 5 parts Sodium lauryl sulfate
0.5 parts potassium stearate
0.5 part water
Uniform dissolution Example 7 Q-decene modified polyvinyl alcohol (q-butene content 6.0 mol%, total saponification degree of vinyl acetate component mol%)
4 parts sodium laurylbenzenesulfonate 2 parts water
Example 8: Uniform dissolution of 10 anchors Example 8: Q-decene modified polyvinyl alcohol (Q-butene content: 3.0 mol%, degree of saponification of vinyl acetate component: 99 mol%)
When a film with a thickness of 30 mm obtained by melt-molding a mixture of 100 parts of sodium lauryl sulfate and 15 parts of sodium lauryl sulfate under substantially anhydrous conditions was soaked in water for 4 days, most of the film was dissolved in water. Ta.

Claims (1)

[Claims] 1. The content of α-olefin having 5 or more carbon atoms is 0.5 to 1.
The method is characterized in that a higher α-olefin modified polyvinyl alcohol obtained by saponifying 50 mol% or more of the vinyl ester component of a 5 mol% α-olefin-vinyl ester copolymer is brought into contact with water in the presence of an anionic surfactant. A method for dissolving higher α-olefin modified polyvinyl alcohol. 2. The method according to claim 1, wherein the α-orphin has 5 to 30 carbon atoms. 3. Claim 1, wherein the anionic surfactant is at least one surfactant selected from the group consisting of alkyl sulfates, alkyl sulfonates, alkylbenzene sulfonates, dialkyl sulfosuccinates, and fatty acid alkali salts. the method of.