JPS6019793B2 - Oil repellent with excellent film forming properties - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oil repellent having excellent film-forming properties, and more specifically, the present invention relates to an oil repellent having excellent film-forming properties, and more specifically, it is composed of a polymerizable compound containing a perfluoroalkyl group, vinylideso chloride, and acrylamide or methacrylamide in a specific ratio. The present invention relates to an oil repellent that is made of a copolymer contained as a unit and has excellent film-forming and oil repellent properties, especially when used in oil-resistant processing of paper.

Conventionally, polymers of compounds such as acrylates or methacrylates containing perfluoroalkyl groups or copolymerization thereof with other polymerizable compounds such as acrylic acid esters, hydrothermal maleic acid, chlorobrene, butadiene, and methyl vinyl ketone have been used. It is known that the combination has water and oil repellent properties, and its use as a water and oil repellent agent for textiles has been developed.

It has also been proposed that a phosphate ester containing a perfluoroalkyl group can be used as an oil repellent for oil-proofing paper. For example, Tokuko Sho 48-477
See Japanese Patent Publication No. 53-77015, US Pat. No. 3,083,224, etc. However, conventional paper oil repellents on the market have the following drawbacks.

That is, since a water-soluble compound such as the above-mentioned phosphate ester is usually employed, it is not possible to impart water repellency to paper. A further important drawback is that the oiliness is significantly reduced when a sizing agent is present. Therefore, when using a commercially available paper twill oil, a special non-sized base paper is required, making it difficult to apply to sized paper. In general, there are two methods for oil-proofing paper: an internal addition method in which paper is made by adding and mixing a processing agent to pulp, and an external addition method in which base paper is impregnated or coated with a processing agent.

In the external addition process, size presses and various coaters are used, and drying is carried out at 80 to 100 o'clock in a short period of several seconds to several tens of seconds. Therefore, with the conventional twill water oil repellent for fibers, the polymer particles do not form into a film during the external additive process of filter paper, and exhibit almost no performance. The applicant has discovered that polymerizable compounds containing perfluoroalkyl groups, vinylidene chloride, and N-methylolacrylamide or N-
The oil repellent agent, which is made of a copolymer containing a specific proportion of methylol methacrylamide as a structural unit, is not easily affected by sizing agents and can be applied not only to unsized paper but also to sized paper, and also provides water repellency. It was previously proposed that it can also be advantageously used in external additive processing as a twill water oil repellent for paper. See Samurai Publication No. 51-133511, etc. The present inventor has conducted various research and studies in order to provide a perfluoroalkyl group-containing polymer that forms a uniform film even when dried at low temperatures and in a short period of time, and exhibits excellent oil repellency for oil-proofing paper using an external addition method. As a result of repeated studies, it has been found that the above object can be advantageously achieved by copolymerizing a perfluoroalkyl group-containing polymerizable compound with vinylidene chloride and acrylamide or methacrylamide in a specific ratio. The present invention is based on the above findings,
CF3 (CF2>7CH2CH20
C.

CH-CH2・CF3kuCF2)4CH20COC(C
H3) ℃ day 2, CF3〆F(CF2)6〈CH2)3
0C. CH go day 2・CF3CF3〆F(CF2)8(C
H2>3MM, CF3, 40 to 7% by weight of a polymerizable compound containing a perfluoroalkyl group having 4 to 1 carbon atoms, and 22% to 22% by weight of vinylidene chloride.
, and a copolymer containing a compound represented by the general formula CH2=C(R)CON2 (wherein R in the formula represents a hydrogen atom or a methyl group) as a constituent unit in a proportion of 1 to 8% by weight. The present invention provides a new twill oil agent.

The oil repellent of the present invention is generally used in the form of an aqueous dispersion in the oil-proofing of paper, but compared to the above-mentioned one containing N-methylolacrylamide as a copolymer component, it can be used in a variety of ways. Advantages are recognized.

First, it has good storage stability as an aqueous dispersion;
Second, the toxicity problem is eliminated, and third, there are manufacturing advantages of the copolymer. That is, N-methylolacrylamides have toxicity problems such as the release of formalin when oil-resistant treated paper is used in food packaging, but the present invention solves these problems. . In addition, copolymers containing N-methylolacrylamides tend to undergo partial crosslinking due to deformalinization during storage, and have difficulty in stability as aqueous dispersions. However, according to the present invention, they are stable on storage. The properties are also good. Furthermore, the acrylamides of the present invention, compared to N-methylolacrylamides,
It has a high copolymerization reaction rate with perfluoroalkyl group-containing polymerizable compounds and vinylidene chloride, and has good latex selectivity in emulsion polymerization, etc., and has no tendency to adhere to block-like by-products or reactor walls. few.
In the present invention, as the perfluoroalkyl group-containing polymerizable compound, various compounds can be exemplified without particular limitation, such as conventionally known or well-known compounds.

For example, CF3〆F(CF2>,.

<CH2) 3MM Japan Go Day 2・CF3CF3kuCF2)6
(CH2) 20COC (CH3) ℃ day 2, CF3〆F
(CF2)5CH2)2ocMHgoday2・CF3CF
3 (CF2>7S02N (C3 day 7) (CH2) 20C
OCHnitH2, CF3(CF2)7(CH2)40C
OCH 2℃ day 2, CF3 (CF2) 7S02N (CH3
)(CH2)20COC(CH3)CH2, CF3(
CF2)6COOCH-CH2, CF3〆F(CF2)
6CH2CH〈〇C.

CH3). C. C(CH3>go day 2・CF3CF3〆F
(CF2)6CH2CH(〇H)CH2MMJapanese/Japanese/Japanese 2・
Unsaturated esters represented by acrylate or methacrylate containing a perfluoroalkyl group having 4 to 1 carbon atoms such as CF3 can be mentioned.

In addition, the perfluoroalkyl group-containing polymerizable compound in the present invention includes CF2CI>CF(CF2)7CONHCOOCH-2°C day 2, C
F3 day (CF2).

CH20COCH ℃ day 2, CF2CI (CF2),.
Compounds that can be polymerized such as CH20COC(CH3) at 2° C. can also be used, but those containing a terminal perfluoroalkyl group as described above are usually preferred. In the present invention, compounds represented by the general formula CH2=C(R)CONQ include acrylamide and methacrylamide.

These can be used alone or in combination. mosquito)
By using acrylamide in combination with vinylidene chloride, a copolymer exhibiting a high degree of oiliness can be obtained. Furthermore, vinylidene chloride improves the film-forming properties of the copolymer. As is clear from the comparative examples below,
If acrylamides are not used, the effect of improving oil repellency will be small, and even if acrylamides are used in combination with alkyl acrylates other than vinylidene chloride, high oil repellency cannot be achieved. In the present invention, if reactivity with vinylidene chloride and a compound corresponding to the general formula OCQ=C(R)CON2, ease of availability, etc. are taken into account,
As a polymerizable compound containing a perfluoroalkyl group, the general formula CH2=(RI)COOR2Rf (where Rf in the formula is a linear or branched perfluoroalkyl group having 4 to 1 needle carbon atoms) is used. , RI is a hydrogen atom or a methyl group, and R2 is a linear or branched divalent alkylene group having 1 to 10 carbon atoms, respectively). It can be said that it is advantageous in terms of commercial use and performance.

It is particularly desirable that Rf be a perfluoroalkyl group having 6 to 14 carbon atoms, and that R2 be a divalent alkylene group having 2 to 4 carbon atoms. Regarding the copolymer of the present invention, the copolymerization ratio of vinylidene chloride is suitably about 22 to 5% by weight, particularly about 25 to 5% by weight, based on the total constitutional units of the copolymer. The copolymerization ratio of the perfluoroalkyl group-containing polymerizable compound is 40 to
7% by weight, preferably about 45-7% by weight. Further, for the compound represented by the general formula C ratio=C(R)CON2, a copolymerization ratio of about 1 to 8% by weight, particularly about 2 to 6% by weight is employed. If vinylidene chloride is too small, the effect of improving low-temperature film forming properties will be reduced, and if it is too large, oil repellency will be impaired. Incidentally, if the amount of vinylidene chloride is too large or too small, the water repellency will decrease. Therefore, if the copolymerization ratio of the compound corresponding to the general formula C=C(R)CON2 is too small, the effect of improving oil repellency will be insufficient, and if it is too large, the water repellency and oil repellency will be reduced. will decrease. In addition to the above-mentioned perfluoroalkyl group-containing polymerizable compound, vinylidene chloride, and a compound corresponding to the general formula C&=C(R)CON, the copolymer in the present invention includes ethylene, vinyl acetate, fluorine Pynyl chloride, vinyl chloride, styrene, Q-methylstyrene, P-methylstyrene, acrylic acid and its lower alkyl esters, methacrylic acid and its lower alkyl esters, diacetone acrylamide, methylolated diacetone acrylamide, benzyl acrylate or methacrylate, cyclohexyl acrylate or does not contain perfluoroalkyl groups such as methacrylate, vinyl alkyl ether, halogenated alkyl vinyl ether, vinyl alkyl ketone, butadiene, isoprene, chloroprene, aziridinyl arylate or methacrylate, glycidyl acrylate, maleic anhydride. It is also possible to copolymerize one or more kinds of polymerizable compounds as constituent units of a copolymer.

By polymerizing these polymerizable compounds that do not contain perfluoroalkyl groups, various properties such as twill water repellency, tear strength, and bending strength can be appropriately improved. In a preferred embodiment of the present invention, in addition to the above-mentioned three types of structural unit components, a non-fluorine-based hydrophobic monomer whose monopolymer has a low glass transition temperature (Tg) of about 0° C. or lower, such as n-butyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, dioctyl maleate, butadiene, vinyl propionate, etc., or cationic monomers such as dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate,
It is desirable to contain salts such as 2-hydroxy-3-dimethylaminopropyl methacrylate (acetate, hydrochloride, etc.) or quaternary ammonium salts as constituent units of the copolymer. By polymerizing a small amount of a cationic monomer, it is possible to improve the mechanical stability of an aqueous emulsion, and by using a low Tg monomer in combination, the film-forming properties of the copolymer can be further improved. Is possible.
The above monomer may be employed in a copolymerization ratio of 10% by weight or less, particularly about 1 to 5% by weight, based on the total constitutional units of the copolymer. In order to obtain the polymer of the present invention, various polymerization reaction methods and conditions can be arbitrarily selected, and any of various polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization can be employed.

For example, a method may be employed in which a mixture of monomers to be copolymerized is emulsified in water in the presence of a surfactant or the like, and the mixture is copolymerized under water.

A polymerization initiator used in polymerization reactions such as ammonium persulfate, potassium persulfate, azobisisobutyramidine dihydrochloride, sodium peroxide, acetyl peroxide, etc. may be added to the reaction system. Further, as the surfactant, various emulsifiers including anionic, ionic, nonionic, or amphoteric emulsifiers can be used. Desirable surfactants include ethylene oxide and isooctylphenol, hexadecanol, oleyl alcohol, alkanethiols having 12 to 16 carbon atoms, and 12 carbon atoms.
Condensation product with ~18 alkylamine etc., carbon number 12
-18 acetates of alkyl amines, and phosphate esters of oleyl alcohol. Therefore, the oil repellent of the present invention is suitably used for oil-proofing paper, and is usually preferably prepared in the form of an aqueous emulsion.

In order to obtain such a form, it is desirable to employ an emulsion polymerization method. In order to increase the emulsion polymerization yield (latex selectivity) and obtain a copolymer with a particle size of 4 mm, it is preferable to add a water-soluble organic solvent to the aqueous medium during the polymerization reaction. For example, glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, acetone, ketones such as methyl ethyl ketone, methyl acetate,
Esters such as ethyl acetate can be employed as the water-dropping organic solvent. The water-soluble organic solvent may be added to the aqueous medium at a concentration of about 5 to 2% by weight. Furthermore, as an emulsifier during emulsion polymerization, it is preferable to use a nonionic surfactant from the viewpoints of chemical stability of the latex, compatibility with auxiliary agents, and the like. For example, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, ethylene oxide dopropylene oxide block copolymer, etc. can be employed as the nonionic surfactant. Furthermore, the emulsion polymerization temperature is preferably about 50 to 6yC; below 50°C, the yield decreases, and above 65qo, the particle size of the resulting copolymer increases. A polymerization time of about 15 to 2 hours is sufficient, and a monomer conversion rate of 99% or more is possible. The oil repellent made of the copolymer of the present invention thus obtained can be applied to the article to be treated by any method.

For example, in the case of an aqueous emulsion, the stock solution is diluted with water to a solids concentration of 0.1 to 2%, and the base paper is soaked using a size press or tab size, or a calender roll or Coating using various roll coaters, 6
By drying at a temperature of 0 to 12,000, grain oil-treated paper is obtained. It may also be applied with a suitable sizing agent if necessary. Next, examples of the present invention will be described in more detail, but it goes without saying that this description does not limit the present invention.

The vertical oil properties shown in the following examples are expressed as oil permeability according to TAPPIRC-338 using the mixed oils shown in Table 1.

Table 1 Example 1 Internal volume 1 In the pressure-resistant polymerization reactor, CH2=CHCOOC
H2C ratio C8F, 750 evenings, vinylideso chloride 45 evenings, acrylamide 5 evenings, deoxygenated ion exchange water 250 evenings,
50 hours of ethylene glycol monomethylenal, 8 hours of polyoxyethylene cetyl ether, and 0.2 hours of azobisisobutyramidine hydrochloride were added, and after sealing, nitrogen gas was introduced to a pressure of 3k9/ground to degas it. .

This nitrogen gas introduction and degassing operation was repeated three times to replace the air in the polymerization reactor with nitrogen gas. Place the reactor in a constant temperature water bath for 30 minutes. p. m. 1 while worshiping the contents with
An instant polymerization reaction was performed. A translucent latex was obtained with a yield of 98%.

This latex was diluted with water to prepare a treated case with a solid content concentration of 0.5% by weight, and the squeezing rate was 5% using a size press.
No size paper (basis weight 50 yen/end) at a speed that makes it 0%
was immersed.

Next, the sand was dried for 19 minutes in a drum dryer flooded to 80 oo. The obtained processed paper showed a twill oiliness of 12.
Examples 2 to 5 and Comparative Examples 1 to 4 Various copolymer latexes having copolymer compositions shown in Table 2 below were synthesized using the same method as in Example 1, and a comparative test of sun oil properties was conducted.

The hot oil treatment method was carried out on the same aircraft as in Example 1, and the test results obtained are summarized in Table 2 below. Table 2 In addition, in the above Table 2, FA is CH2=CHCOOC
H2C average CnF2n+, n=6, 8, 10, 12 is 0.
5:3:2:1), Vdc12 is vinylidene chloride, AM
is acrylamide, EA is ethyl acrylate, MMA
indicates methyl methacrylate, and BA indicates butyl acrylate.

Example 6 As monomers, FA50, vinylidene chloride42, acrylamide5, and CH2=C(CH3)COO
CH2CH2N Yu (CH3)3. A copolymer latex was obtained by polymerizing in the same manner as in Example 1 using CIe3.

Claims (1)

[Scope of Claims] 1 40 to 70% by weight of a polymerizable compound containing a perfluoroalkyl group having 4 to 16 carbon atoms, 58 to 22% by weight of vinylidene chloride, and a compound having the general formula CH_2=C(R
) An oil repellent made of a copolymer containing a compound represented by CONH_2 (in the formula, R represents a hydrogen atom or a methyl group) in a proportion of 1 to 8% by weight as a constitutional unit. 2 Polymerizable compound containing perfluoroalkyl group, vinylidene chloride, and CH_2=C(R)CONH
In addition to _2, the glass transition temperature (Tg) of the homopolymer
The oil repellent according to claim 1, wherein the non-fluorine-based hydrophobic monomer having a temperature of 0°C or less is contained as a copolymerization unit in a copolymerization ratio of 10% by weight or less of all the constituent units of the copolymer. . 3 Polymerizable compounds containing perfluoroalkyl groups, vinylidene chloride, and CH_2=C(R)CONH
The oil repellent according to claim 1, wherein, in addition to _2, a cationic monomer is contained as a structural unit in a copolymerization ratio of 10% by weight or less of the total structural units of the copolymer. 4. The oil repellent according to claim 1, 2, or 3, which is prepared in the form of an aqueous emulsion of the copolymer.