JPH0564963B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field] The method of the present invention relates to a novel fluorine-containing polymeric substance, a method for producing the same, and a Langmuir Blossom film thereof. [Prior Art] Polymer compounds decorated with long-chain perfluoroalkyl groups exhibit excellent properties such as water and oil repellency, dustproofness, and corrosion resistance, and are used as surface-modifying materials to protect substrates. It is also excellent as a material for oxygen permeable membranes, and the oxygen permeability of the perfluoroalkyl group improves the selectivity of oxygen permeation. However, polymer compounds into which perfluoroalkyl groups have been introduced are difficult to dissolve in solvents due to the water and oil repellency of the perfluoroalkyl groups, making them difficult to use as membrane materials. In other words, it is difficult to form ultra-thin films, which are important as surface modification materials and substrate protection materials. Also,
Controlling the arrangement of perfluoroalkyl groups, which are functional groups such as water and oil repellency and oxygen affinity, on the surface of polymers is important for improving the performance of the polymer as a surface modification material and oxygen separation membrane. Controlling the arrangement on a surface is not easy. The present inventor modified polyallylamine or polyvinylamine with a perfluoroalkyl group through an amide bond or a urea bond, and used these polymers to create an ultra-thin film with controlled molecular arrangement using the Langmuir-Blodget method [Showa Patent Application No. 1350 of 1962, Patent Application No. 32188 of 1988, Patent Application No. 32189 of 1988]. However, there are problems such as gradual hydrolysis of amide bonds in solution or low solubility and difficulty in handling, and there is a desire for the development of new ultra-thin film materials. [Purpose] The present inventor has conducted extensive research on a method for creating an ultra-thin film that utilizes the hydrophobicity of perfluoroalkyl groups, and has developed an o-, m-, or p-(perfluoroalkyl ) It was discovered that a polymer compound obtained by modification with a phenyl group is suitable as an ultra-thin film material, and the present invention was completed. [Configuration] According to the present invention, the general formula (In the formula, Rf represents a perfluoroalkyl group having 6 to 15 carbon atoms, and the bonding position of the Rf group to the benzene ring is o-, m-, or p-position, and m is 10-15.
The number is 1500, and n is a number satisfying 0<n<0.6m. ) is provided. The fluorine-containing polymer compound according to the present invention comprises polyallylamine represented by the following general formula (), and o-, m-, or p-(perfluoroalkyl) phenylisothiocyanate represented by the general formula (). It is produced by reacting according to the following formula. (In the formula, Rf, m and n have the same meanings as above.) The polyallylamine used in the above reaction was obtained by neutralizing polyallylamine hydrochloride (average molecular weight about 9000) with a base. In the modification reaction of polyallylamine, a mixed solvent of alcohol and benzene is used as a reaction solvent, and the reaction temperature is 5°C to 50°C, preferably 15°C.
Can be carried out at ~30°C. To carry out this reaction preferably, o-, m-, or p-(perfluoroalkyl) phenyl isothiocyanate is added to a mixed solvent of polyallylamine alcohol and benzene. By varying the amount of (perfluoroalkyl)phenyl isothiocyanate added, polyallylamine can be modified with o-, m-, or p-(perfluoroalkyl)phenyl groups with thiourea bonds in any proportion. After stirring for several minutes to several hours, the reaction solution was concentrated, washed with water,
The obtained polymer compound is dried. The obtained fluorine-containing polymer was identified by infrared absorption spectrum to be a fluorine-containing polyallylamine represented by the above general formula (). The fluorine-containing polyallylamine represented by the general formula () of the present invention dissolves in an organic solvent, and easily forms a monomolecular film by spreading this dilute solution on the water surface.
Langmis arrogant film can be created. From the measurement of the surface pressure-surface area curve (FA curve) when this fluorine-containing polymer was spread on the water surface, o-,
It can be seen that in both the m- and p-isomers, an ultra-thin film in which the area occupied by one (perfluoroalkyl)phenyl group becomes larger can be created by reducing the modification rate of polyallylamine. Also,
When compared at the same modification rate, the area occupied by one (perfluoroalkyl) phenyl group decreases in the order of o-, m-, and p-, and in particular, the modification rate of the amino group in polyallylamine of the p-isomer is 40%. The cross-sectional area of the perfluoroalkyl group is 28 Å.
It became clear that the value was less than half of ² .
From this, the arrangement state of the (perfluoroalkyl)phenyl group in this thin film changes not only depending on the modification rate but also the isomer of the benzene ring, and in the case of a modification rate of 40% of the p-isomer, the perfluoroalkyl)phenyl group changes depending on the benzene ring isomer. It turned out to be an ultra-thin film with an arrangement of overlapping groups. Furthermore, from the rise of the F-A curve, it can be seen that this Langmuir-Blodget film is a stable film. One layer or multiple layers of this ultra-thin film were scooped out onto a glass substrate, and the film thickness and critical surface tension γcdyn/cm for n-alkanes were determined. As a result, the γc value was almost the same for 1 layer and 5 layers. , and also o-,
In both cases of m- and p-isomers, the higher the degree of modification to polyallylamine, the smaller the value. The o-isomer shows approximately 21-17 dyn/cm,
The m-isomer showed about 19-15 dyn/cm, and the p-isomer showed about 18-15 dyn/cm. These γc
The value is the γc value of polytetrafluoroethylene
It can be said that these films are excellent films with low surface energy, which is close to 18.5 dyn/cm. [Effect] That is, the present invention is a reagent for introducing o-, m-, or p-(perfluoroalkyl) phenyl groups into polyallylamine through a thiourea bond.
-, m-, or p- (perfluoroalkyl)
Modifications can be made in various proportions by arbitrarily varying the amount of phenyl isothiocyanate. The obtained fluorine-containing polymer compound is soluble and can be formed into an ultra-thin film by the Langmuir-Blodget method, and can be used as an unprecedented ultra-thin film surface-modifying substance. Furthermore, the area occupied by one (perfluoroalkyl)phenyl group in this ultra-thin film can be controlled by changing the modification rate of the (perfluoroalkyl)phenyl group to polyallylamine and the positional isomer of the benzene ring. Furthermore, the surface of these films contains perfluoroalkyl groups, which are functional groups, and exhibits the excellent low surface energy property characteristic of fluorine-containing groups. Furthermore, the surface state of this film can be controlled by changing the degree of modification of the (perfluoroalkyl)phenyl group to polyallylamine and the positional isomerism of the benzene ring. It can be changed from a high state to a lower state. Conventionally, there has been an example in which a fluorine-containing group having a benzene ring was modified with a thiourea bond to polyallylamine, and a functional ultra-thin polymer film with sequence control within and between molecules was created using the Langmuir-Blodget method. do not have. In this specification, the term "Langmeur Blossom film" refers to a monomolecular film or a cumulative film obtained by the conventionally well-known Langmuir Blossom film. [Example] Next, the present invention will be explained in more detail with reference to Examples. Example 1 Add 116 mg of metallic sodium to 9 ml of methanol,
After no hydrogen is generated, add 469.6 mg of polyallylamine chlorine salt (average molecular weight, approximately 9000), cover and stir. The precipitated sodium chloride is removed by filtration, and 11 ml of methanol and 5 ml of benzene are added. To this solution, 139.3 mg of p-(perfluorooctyl) phenyl isothiocyanate was dissolved in a mixed solvent of 4 ml of methanol and 1 ml of benzene and added at once. This reaction solution is homogeneous and can be used as it is as a stock solution of a polymer solution for producing a Langmuir Blossom film. The solvent is removed from this solution under reduced pressure, and 5% of the amino groups in the polyallylamine are washed with water and dried.
A polymer modified with (perfluorooctyl)phenyl groups was obtained. The obtained polymer was determined by infrared absorption spectrum to have a carbonate-fluorine bond: 1300~
This was confirmed by the observation of strong absorption at 1100 cm ^-1 . In a similar manner, using o-, m-, or p-(perfluorooctyl) phenyl isothiocyanate, for the amino group of polyallylamine,
The reaction was carried out at a molar ratio of 5, 10, 20, 30, 40%,
Polymer compounds with modification rates of 5, 10, 20, 30, and 40% were obtained, respectively. However, polymer compounds with a modification rate of 30% or more were difficult to dissolve in the reaction solvent, and some of them precipitated during the reaction. Example 2 Preparation of Langmuir Blossom film The fluorine-containing polymer synthesized in Example 1 was modified with each isomer (o-, m-, p-) and (perfluoroalkyl) phenyl group modification rate (M%). ) is abbreviated as (o-, m-, p-)PAPHF(M). In the Langmeur Blosget method, o
-, m-, and p-PAPHF5, 10, 20, 30, 40
Prepare a dilute mixed solution of trifluoroethanol and benzene (a dilute mixed solution of methanol and benzene in the case of p-PAPHF5, 10, and 20), respectively.
FIG. 1 shows the results of measuring the relationship between surface pressure and surface area (FA curve) when these solutions were spread on a water surface at 17°C. Based on this result, the area occupied by one molecule of fluoroalkyl group in the membrane, that is, the ultimate area is o-PAPHF5, 10, 20, 30, 40
87, 87, 63, 57, 45 Å ² , m-
88 each in the order of PAPHF5, 10, 20, 30, 40,
74, 54, 48, 33Å ² , p-PAPHF5, 10, 20,
The values of 30 and 40 were 71, 57, 32, 31, ^{and 11 Å2} , respectively. This ultra-thin film on the water surface is placed on a glass substrate under surface pressure.
It was transferred as a monomolecular film and a cumulative film at 20 mN·m ^-1 . These were transparent films. Example 3 Setting the critical surface tension γc For the monomolecular film and the cumulative film transferred onto the glass substrate in Example 2, the contact angle with n-alkane was set, and the critical surface tension γc value was determined from the Zisman plot. was calculated using the least squares method. These results are shown in Table 1. Example 4 Measurement of film thickness A 19-layer cumulative film of the Langmuir-Blodget film obtained in Example 2 (7 for o-PAPHF20 and 30)
The film thickness was measured using a Taly step using a stacked layer film (12 layer stacked film for o-PAPHF10 and p-PAHF10). That is, a portion of the thin film was peeled off and the level difference between the film and the substrate was measured using a Talystep. The obtained film thickness was divided by the number of cumulative layers to obtain the film thickness of one layer. These results are shown in Table 1.

【table】

【table】 [Brief explanation of the drawing]

FIG. 1 shows the F-A curve of the fluorine-containing polymer Langmeur Blossom film according to the present invention.

Claims (1)

[Claims] 1. General formula (In the formula, Rf represents a perfluoroalkyl group having 6 to 15 carbon atoms, the bonding position of the Rf group to the benzene ring is o-, m-, or p-position, and m is 10 to
The number is 1500, and n is a number satisfying 0<n<0.6m. ) A fluorine-containing polymer compound represented by 2 General formula (In the formula, Rf represents a perfluoroalkyl group having 6 to 15 carbon atoms, the bonding position of the Rf group to the benzene ring is o-, m-, or p-position, and m is 10 to
The number is 1500, and n is a number satisfying 0<n<0.6m. ) In the method for producing a fluorine-containing polymer compound represented by the general formula (In the formula, m has the same meaning as above.) A polyallylamine represented by the general formula (wherein Rf has the same meaning as above). 3 General formula (In the formula, Rf represents a perfluoroalkyl group having 6 to 15 carbon atoms, and the bonding position of the Rf group to the benzene ring is o-, m-, or p-position, and m is 10-15.
The number is 1500, and n is a number satisfying 0<n<0.6m. Langmuir Blossom film using a fluorine-containing polymer compound represented by ).