JPH06306122A - Heat-sensitive high-molecular compound and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain the compound which undergoes phase transition when subjected to thermal stimulation in water, by the radical polymerization of a specified vinyl compound. CONSTITUTION:The compound is obtained by the radical polymerization of a vinyl compound of formula I (wherein R is H or CH3) [e.g. N-2- isopropoxyethyl(meth)-acrylamide]. It consists of repeating units of formula II and has a molecular weight corresponding to an intrinsic viscosity [eta] of 0.01-6.0 in solution in tetrahydrofuran at 27.5 deg.C.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel thermosensitive polymer compound which undergoes a phase transition in water and a method for producing the same. More specifically, the present invention relates to a light-shielding polymer, a temperature sensor, an adsorbent, a toy, an interior, a textile printing agent, a display, a separation membrane, a heat-sensitive polymer compound having a phase transition in water, which can be used for a mechanochemical material. The present invention relates to a method for efficiently manufacturing this product.

[0002]

2. Description of the Related Art Among water-soluble polymer compounds, they show a special reversible dissolution behavior in which, when they are in an aqueous solution state, they become cloudy at a certain temperature (transition temperature or cloud point) or more, and they become soluble and transparent below the temperature. These are also called hydrophilic-hydrophobic thermoreversible polymer compounds or heat-sensitive polymer compounds, and in recent years, such as greenhouses and other light-shielding substances, temperature sensors or nonionic surfactant adsorbents, etc. It has come to be noticed as a material.

As such a heat-sensitive polymer compound,
So far, partially saponified polyvinyl acetate, polyvinyl methyl ether, methyl cellulose, polyethylene oxide, polyvinyl methyl oxazolidinone, polyacrylamide derivatives and the like are known.

Among these heat-sensitive polymer compounds, polyacrylamide derivatives are particularly useful because they are stable in water and can be produced at a relatively low cost. So far, poly (N-ethylacrylamide) and poly (acrylamide) have been used. (Nn-propyl (meth) acrylamide), poly (N-isopropyl (meth) acrylamide), poly (N-cyclopropyl (meth) acrylamide), poly (N, N-diethylacrylamide), poly (N-methyl) -N-ethylacrylamide), poly (N-methyl-Nn-propylacrylamide), poly (N-methyl-N-isopropylacrylamide), poly (N-acryloylpiperidine), poly (N-acryloylpyrrolidine), poly (N
-Tetrahydrofurfuryl (meth) acrylamide),
Poly (N-methoxypropyl (meth) acrylamide), poly (N-ethoxypropyl (meth) acrylamide), poly (N-isopropoxypropyl (meth) acrylamide), poly (N-ethoxyethyl (meth) acrylamide), poly (N- (2,2-dimethoxyethyl) -N-methylacrylamide), poly (N-1-methyl-2-methoxyethyl (meth) acrylamide),
Poly (N-1-methoxymethylpropyl (meth) acrylamide), poly (N- (1,3-dioxolane-2-
Ilmethyl) -N-methylacrylamide), poly (N
-8-acryloyl-1,4-dioxa-8-aza-spiro [4.5] decane) and the like are known.

However, these heat-sensitive polymer compounds have a limited transition temperature even if they are used as temperature sensors or light-shielding bodies, and cannot be arbitrarily selected according to the purpose. Was not restricted.

[0006]

Under these circumstances, the object of the present invention is to provide a thermosensitive polymer compound which undergoes a phase transition in water by thermal stimulation in order to expand the range of application of the thermosensitive polymer compound. And to provide a method for manufacturing the same.

[0007]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors to develop a heat-sensitive polymer compound that undergoes a phase transition in water, the general formula

A general formula obtained by radical polymerization of a vinyl compound represented by the formula

It consists of a repeating unit represented by the following formula and has an intrinsic viscosity [η] at a temperature of 27 ° C. in a tetrahydrofuran solution.
It was found that a polymer compound having a molecular weight corresponding to 0.01 to 6.0 is a thermosensitive polymer compound that undergoes a phase transition in water, and the present invention has been completed based on this finding.

The polymer compounds of the present invention are poly (N-2-isopropoxyethyl acrylamide) and poly (N-2-isopropoxyethyl methacrylamide), which are novel compounds which have not been published in the literature, and are vinyl compounds mentioned above. It can be easily produced by radical polymerization.

These vinyl compounds, namely N-2-isopropoxyethyl acrylamide and N-2-isopropoxyethyl methacrylamide are also novel compounds,
For example, the general formula

[Chemical 3] According to the method described above, acrylic acid chloride or methacrylic acid chloride, 2-aminoethylisopropyl ether and triethylamine are reacted in a solvent kept at 0 to 10 ° C, or

[Chemical 4] According to the procedure, acrylic acid chloride or methacrylic acid chloride and 2-aminoethyl isopropyl ether were
It can be obtained by reacting in a solvent kept at -10 ° C.

The solvent used in these methods is not particularly limited as long as it is inert to acrylic acid chloride and methacrylic acid chloride, and generally benzene,
Acetone, toluene, etc. are used. Regarding the reaction temperature, if it is too high, side reactions occur, so it is preferable to react in the range of 0 to 10 ° C.

From the reaction mixture thus obtained,
To isolate the target compound, usually, first, triethylamine hydrochloride or 2-aminoethylisopropyl ether hydrochloride is removed by filtration or the like, then the solvent is distilled off from the filtrate by using a rotary evaporator, and then the pressure is reduced by a conventional method. Purify by distillation. At this time, if necessary, vacuum distillation may be further repeated to obtain a highly pure product.

The N-2-isopropoxyethylacrylamide thus obtained had a boiling point of 118 ° C./2 mm.
Hg) A colorless liquid, soluble in solvents such as water, methyl alcohol, ethyl alcohol, acetone, tetrahydrofuran, chloroform, benzene, n-hexane, n
-Insoluble in heptane.

N-2-isopropoxyethylmethacrylamide is a colorless liquid (boiling point: 108 ° C./1 mmHg), which is soluble in water, methyl alcohol, ethyl alcohol, acetone, tetrahydrofuran, chloroform, benzene and the like. It is insoluble in n-hexane and n-heptane.

The heat-sensitive polymer compound of the present invention which undergoes a phase transition in water can be produced by radical polymerization of the above-mentioned N-2-isopropoxyethyl acrylamide or N-2-isopropoxyethyl methacrylamide. However, this polymerization is usually a solution polymerization method or a bulk polymerization method, using benzoyl peroxide, a peroxide such as peracetic acid or an azo compound such as azobisisobutyronitrile as a polymerization initiator, or an ultraviolet ray, Radiation, electron beam,
It can be performed by irradiation with actinic rays such as plasma. The amount of the polymerization initiator used at this time is 0.005 to 5% by weight, and particularly 0.001 to 5% by weight, based on the weight of the monomer.
A range of 2% by weight is suitable.

Especially preferred is the solution polymerization method, N-2.
-Isopropoxyethyl acrylamide or N-2
-A method in which isopropoxyethyl methacrylamide is dissolved in an organic solvent at a concentration of 1 to 80% by weight and polymerized. The solvent used in such a solution polymerization method is not particularly limited as long as it is soluble in N-2-isopropoxyethyl acrylamide or N-2-isopropoxyethyl methacrylamide. For example, water, alcohols, acetone, tetrahydrofuran, chloroform, benzene, alkyl acetates and the like can be mentioned, and these may be used alone or in combination of two or more depending on the case.

The polymer compound of the present invention is -CONH-
Since it has a group, a —CH ₂ —O— group, a —CH ₂ group, a —CH ₃ group, etc., it can be identified by an infrared absorption spectrum or the like. Regarding the degree of polymerization, it is practical that the intrinsic viscosity [η] at a temperature of 27 ° C. in a tetrahydrofuran solution is in the range of 0.01 to 6.0. Regarding the solubility in various solvents, cold water,
It is soluble in methanol, acetone, benzene, tetrahydrofuran, methyl acetate, ethyl acetate, ethylene glycol, chloroform and the like, but insoluble in cyclohexane, n-hexane, n-heptane and the like.

The polymer compound of the present invention has a property that it dissolves in water below the transition temperature and becomes insoluble at the transition temperature or higher. For example, the transition temperature of a 1% aqueous solution of this polymer compound varies depending on the molecular weight and the solution concentration.
2-isopropoxyethylacrylamide) 15-
18 ° C., 21 to 23 ° C. for poly (N-2-isopropoxyethylacrylamide).

[0018]

INDUSTRIAL APPLICABILITY The polymer compound of the present invention is a polymer compound which has not been published in the literature, and has the property of being soluble in water at low temperatures and insoluble in water at high temperatures. These polymers can be used in, for example, light-shielding bodies such as greenhouses, temperature sensors, toys, interiors, textile printing agents, displays, separation membranes, cosmetic base materials, mechanochemical element materials, and the like.

[0019]

The present invention will be described in more detail with reference to Reference Examples and Examples.

Reference Example 1 Triethylamine (30.71 g), 2
-Add aminoethyl isopropyl ether (31.00 g) and toluene (450 ml), cool with ice, and cool the contents to 10 ° C.
While maintaining the temperature below, while stirring, acrylic acid chloride (24.9 ml) was diluted with toluene (50 ml) and slowly added dropwise from the dropping funnel over about 3 hours. After completion of dropping
The reaction solution was left in the refrigerator overnight to complete the reaction, then filtered, toluene was distilled off using a rotary evaporator, and crude N-2-isopropoxyethylacrylamide was concentrated. Then, it is distilled under reduced pressure by a conventional method to give a boiling point of 118.
27.54 g of a liquid substance having a temperature of / 2 mmHg was obtained.

The infrared absorption spectrum of this substance is shown in FIG.
Tables 1 and 2 show the results of infrared spectrum analysis and mass spectrum analysis.

[Table 1]

[Table 2]

From the above analysis results, it was confirmed to be N-2-isopropoxyethylacrylamide.

Reference Example 2 Triethylamine (30.71 g), 2
-Add aminoethyl isopropyl ether (31.00 g) and toluene (450 ml), cool with ice, and cool the contents to 10 ° C.
Methacrylic acid chloride (24.9 ml) was diluted with toluene (50 ml) while stirring at the following temperature, and the mixture was slowly added dropwise from a dropping funnel over about 3 hours. After completion of the dropwise addition, the reaction solution was left in the refrigerator overnight to complete the reaction, then filtered, toluene was distilled off using a rotary evaporator, and crude N-2-isopropoxyethylacrylamide was concentrated. Then, vacuum distillation was carried out by a conventional method to obtain 41.76 g of a liquid substance having a boiling point of 108 ° C./1 mmHg.

The infrared absorption spectrum of this substance is shown in FIG.
Tables 3 and 4 show the results of infrared spectrum analysis and mass spectrum analysis.

[Table 3]

[Table 4]

From the above analysis results, it was confirmed to be N-2-isopropoxyethylmethacrylamide.

Example 1 The vinyl monomer polymer compound obtained in Reference Example 1 was produced. N-2-isopropoxyethylacrylamide 1.
93 g, 20 ml of benzene and 0.02 g of AIBN were placed in an ampoule, which was connected to a vacuum line, frozen and thawed under reduced pressure to remove oxygen in the ampoule, and then the ampoule was sealed. The polymerization reaction was carried out by heating this ampoule at 50 ° C. for 9 hours. The resulting polymer was isolated by mixing in n-hexane with the reaction solvent. Then, it was dissolved in water and freeze-dried to obtain a polymer. Yield = 1.86g.

The infrared absorption spectrum of this polymer compound is shown in FIG. By comparing the infrared absorption spectrum of vinyl monomer with that of high molecular compound, 1627CM ^-1
It was confirmed that the vinyl group disappeared and that a polymer compound was produced.

About the obtained polymer compound, a tetrahydrofuran solution was prepared, and it was measured with an Ubbelohde viscometer to obtain 27
Viscosity was measured at ° C to determine the intrinsic viscosity [η]. Intrinsic viscosity [η] = 0.65.

Further, the heat-sensitive characteristics were investigated by measuring the light transmittance of the aqueous solution by thermal stimulation. The light transmittance of a 1 wt% aqueous solution at a wavelength of 500 nm was measured using a spectrophotometer with a temperature controller at a rate of temperature increase of 1 ° C./min and a rate of temperature decrease of 1 ° C./min. The transmittance-temperature curve of the aqueous solution of the polymer of Example 1 is shown in FIG. Among them, the solid line is the data when the temperature is raised and the dotted line is the data when the temperature is lowered. The transition temperature was obtained from the temperature ( _TL ) at which the light transmittance of the aqueous solution at the time of temperature rise was 0.5 of the initial transmittance.
T _L = 15.0 ℃

Example 2 N-2-isopropoxyethylacrylamide 1.93
g, 20 ml of methanol and 0.02 g of AIBN were placed in an ampoule, the ampoule was connected to a vacuum line, frozen and thawed under reduced pressure to repeatedly remove oxygen in the ampoule, and then the ampoule was sealed. The polymerization reaction was carried out by heating this ampoule at 50 ° C. for 24 hours. The resulting polymer is
After removing the solvent, an acetone solution was prepared and mixed in n-hexane for isolation. Then dissolve in water and freeze-dry.
A polymer was obtained. Yield = 1.77g.

The production of a polymer compound was confirmed by the same method as in Example 1 below. Intrinsic viscosity [η] = 0.26 in tetrahydrofuran solution at 27 ° C.

The transition temperature of the aqueous solution was determined in the same manner as in Example 1. T _L = 17.6 ° C.

Example 3 The vinyl monomer polymer compound obtained in Reference Example 2 was produced. 1.93 g of N-2-isopropoxyethyl methacrylamide, 20 ml of benzene and 0.02 g of AIBN
Was placed in an ampoule, the ampoule was connected to a vacuum line, frozen and thawed repeatedly under reduced pressure to remove oxygen in the ampoule, and then the ampoule was sealed. The polymerization reaction was carried out by heating this ampoule at 50 ° C. for 24 hours. The resulting polymer was isolated by mixing in n-hexane with the reaction solvent. Then, it was dissolved in water and freeze-dried to obtain a polymer. Yield = 1.36g.

The infrared absorption spectrum of this polymer compound is shown in FIG. By comparing the infrared absorption spectrum of vinyl monomer with that of polymer compound, 1621CM ^-1
It was confirmed that the vinyl group disappeared and that a polymer compound was produced.
The production of the polymer compound was confirmed in the same manner as in Example 1 below. Intrinsic viscosity [η] = 0.12 at 27 ° C. in tetrahydrofuran solution. The transition temperature of the aqueous solution was determined in the same manner as in Example 1. T _L = 22.0 ° C.

Example 4 N-2-isopropoxyethyl methacrylamide 1.9
2 g, 20 ml of methanol and 0.02 g of AIBN were placed in an ampoule, which was connected to a vacuum line and frozen and thawed repeatedly under reduced pressure to remove oxygen in the ampoule, and then the ampoule was sealed. The polymerization reaction was carried out by heating this ampoule at 50 ° C. for 24 hours. The resulting polymer is
After removing the solvent, an acetone solution was prepared and mixed in n-hexane for isolation. Then dissolve in water and freeze-dry.
A polymer was obtained. Yield = 1.77g.

The formation of a polymer compound was confirmed by the same method as in Example 1 below. 27 ° C in tetrahydrofuran solution
Intrinsic viscosity [η] = 0.07. The transition temperature of the aqueous solution was determined in the same manner as in Example 1. T _L = 22.0 ° C.

[0037]

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum of the vinyl monomer of Reference Example 1.

2 shows an infrared absorption spectrum of the polymer compound of Example 1. FIG.

FIG. 3 is a transmittance-temperature curve of a 1% by weight aqueous solution of the polymer compound of Example 1.

FIG. 4 is an infrared absorption spectrum of the vinyl monomer of Reference Example 2.

5 shows an infrared absorption spectrum of the polymer compound of Example 3. FIG.

FIG. 6 is a transmittance-temperature curve of a 1% by weight aqueous solution of the polymer compound of Example 3.

Claims (2)

[Claims] 1. A general formula: A general formula characterized by radically polymerizing a vinyl compound represented by And has an intrinsic viscosity [η] of 0.07 at a temperature of 27 ° C. in a tetrahydrofuran solution.
A method for producing a heat-sensitive polymer compound having a molecular weight corresponding to 1 to 6.0. 2. An intrinsic viscosity [η] in a tetrahydrofuran solution at a temperature of 27 ° C., which comprises a repeating unit represented by the general formula:
Is a heat-sensitive polymer compound having a molecular weight corresponding to 0.01 to 6.0.