JPH03273012A - Heat-sensitive polymeric compound which undergoes phase transition in monoalcohol and its production - Google Patents

Abstract

PURPOSE:To obtain the title compound which can reversibly undergoes dissolution in a monoalcohol in a high temperature region and insolubilization in a monoalcohol in a low temperature region and can be used as a temperature sensor or the like by selecting a heat-sensitive polymeric compound comprising specified repeating units and having a specified molecular weight. CONSTITUTION:A heat-resistant polymeric compound comprising repeating units of the formula and having a molecular weight corresponding to a limiting viscosity of 0.01-6.0 (at 27 deg.C) in an aqueous solution is selected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a novel heat-sensitive polymer compound that undergoes phase transition in an m-alcohol solvent and a method for producing the same. More specifically, the present invention provides a highly heat-sensitive material that undergoes a phase transition in m-alcohol solvents and can be used for light shields, temperature sensors, adsorbents, toys, interior decorations, textile printing agents, displays, separation membranes, and mechanochemical materials. This invention relates to molecular compounds and methods for efficiently producing them.

[Conventional technology]

Some water-soluble polymer compounds exhibit a special reversible dissolution behavior in which they precipitate and become cloudy above a certain temperature (transition temperature or cloud point) in an aqueous solution state, and dissolve and become transparent below that temperature. This material is also called a woody-hydrophobic thermoreversible polymer compound or a heat-sensitive polymer compound, and has recently attracted attention as a material for light shields in greenhouses, temperature sensors, and water-soluble organic substance adsorbents. It's starting to look like this.

Until now, such heat-sensitive polymer compounds include partially saponified polyvinyl acetate, polyvinyl methyl ether,
Methyl cellulose, polyethylene oxide, polyvinylmethyloxasilideinone, and polyacrylamide derivatives are known. Among these heat-sensitive polymer compounds, polyacrylamide derivatives are stable in water and can be produced at relatively low cost. is particularly useful, and so far poly(N-ethyl acrylamide), poly(N-n-
poly(N-isopropyl(meth)acrylamide), poly(N-cyclopropyl(meth)acrylamide), poly(N,
N-diethylacrylamide), poly(N-methyl-N
-ethyl acrylamide), poly(N-methyl-N-n
-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-dioxolan-2-yl)-N-methyl acrylamide)
, poly(N-8-acryloyl-1゜4-dioxa-8
-aza-spiro [4.5] decane) etc. are known.

However, all of these heat-sensitive polymer compounds show heat sensitivity in an aqueous solution, but do not show heat sensitivity in other solvents. Polymers exhibiting heat sensitivity in -valent alcohol solvents include poly(N-1,3-dioxolane-2
-yl)-N-methylacrylamide), which, unlike the above-mentioned heat-sensitive polymers, is insoluble at temperatures below the transition temperature and soluble at temperatures above the transition temperature (Published Patent Publication No. 1983-243112). )).

[Problem to be solved by the invention]

Under these circumstances, the present invention was developed to expand the scope of use of heat-sensitive polymer compounds, and to expand the scope of use of heat-sensitive polymer compounds. The purpose of this invention is to provide a manufacturing method for the same.

[Means to solve the problem]

As a result of intensive research to develop a heat-sensitive polymer compound that undergoes a phase transition in a -hydric alcohol solvent, the present inventors discovered a compound obtained by radical polymerization of a vinyl compound represented by the formula % (). It consists of repeating units represented by the formula % formula %, and 27
It was discovered that a polymer compound having a molecular weight corresponding to an intrinsic viscosity [η] of 0.01 to 6.0 at a temperature of ℃ is a heat-sensitive polymer compound that undergoes a phase transition in a -hydric alcohol solvent. The present invention was completed based on the findings.

The polymer compound of the present invention is poly(N-(1,3-dioxolan-2-yl)acrylamide), which is a novel compound published by Bunyu, and is a radical compound of poly(N-(1,3-dioxolan-2-yl)acrylamide). It can be easily produced by polymerization.

The compound represented by this formula (I), that is, N-(1,3
-dioxolan-2-yl)acrylamide is also a new compound, for example, according to the reaction formula %, acrylic acid chloride and 2-aminomethyl-1,
3-dioxolane and triethylamine at 0 to 10°C.
Alternatively, acrylic acid chloride and 2-aminomethyl-1,
It can be obtained by reacting with 3-dioxolane in a solvent maintained at 0 to 10°C.

The solvent used in these methods is not particularly limited as long as it is inert to acrylic acid chloride, and benzene, acetone, toluene, etc. are generally used.

Regarding the reaction temperature, if it is too high, side reactions will occur, so
It is preferable to carry out the reaction in the range of 0 to 10°C.

To isolate the target compound from the reaction mixture thus obtained, usually first, triethylamine hydrochloride or 2-aminomethyl-1,3-dioxolane hydrochloride is removed by filtration, etc., and then a rotary evaporator is used. The solvent is distilled off from the filtration using cyclohexane, followed by recrystallization using cyclohexane for purification. At this time, if necessary, recrystallization can be repeated to obtain high purity.

The N-(1,3-dioxolan-2-yl)acrylamide thus obtained is a colorless crystalline solid (melting point: 70° to 8°C) that can be mixed with water, methyl alcohol, ethyl alcohol, acetone, tetrahydrofuran, Compatible with solvents such as chloroform and benzene.

The thermosensitive polymer compound of the present invention that undergoes a phase transition in m alcohol solvents is the aforementioned N-(1,3-dioxolane-2-
By radical polymerizing acrylamide)
However, this polymerization is usually carried out by solution polymerization or bulk polymerization using a peroxide such as benzoyl peroxide or peracetic acid or an azo compound such as azobisisobutyronitrile as a polymerization initiator. This can be carried out by irradiation with actinic rays such as ultraviolet rays, radiation, electron beams, and plasma. The amount of polymerization initiator used at this time is:
0.005 to 5% by weight, based on the weight of the monomers, especially 0
．． A range of 0.001 to 2% by weight is suitable.

Particularly preferred is a solution polymerization method in which N-(1゜3-dioxolan-2-yl)acrylamide is dissolved in an organic solvent at 1%.
This is a method of dissolving and polymerizing at a concentration of ~80% by weight.

Regarding the solvent used in such solution polymerization method, N-
There is no particular restriction as long as it dissolves (1,3-dioxolan-2-yl)acrylamide. For example, water,
Alcohols, acetone, tetrahydrofuran, chloroform, benzene, alkyl acetates, etc. can be mentioned, and these may be used alone or in combination of two or more types depending on the case.

The polymer compound of the present invention is a high temperature soluble heat-sensitive polymer compound that is insoluble in m alcohols at low temperatures and soluble in m alcohols at high temperatures. The transition temperature of this is −
It also varies depending on the type of alcohol.

The polymer compound of the present invention has a -CONH- group, a CH20-
Since it has a -CH< group, it can be identified by infrared absorption spectrum. Regarding the degree of polymerization, it is practical that the intrinsic viscosity [η] in an aqueous solution at a temperature of 27°C is in the range of 0.01 to 6.0. Furthermore, regarding solubility in various solvents, water, heat
Hydrolic alcohols, ethylene glycol, chloroform, etc. have m solution, cold alcohols, acetone, benzene, etc.
Tet=-+$V It is insoluble in alkyl acetates such as furan, methyl acetate, ethyl acetate, and n-butyl acetate, diethyl ether, n-hexane, and n-hebutane.

When the polymer compound of the present invention is heated above the transition temperature, m
It has the property of being soluble in alcohol at high temperatures and becoming insoluble when cooled. For example, the transition temperature of a 1%-hydric alcohol solution of this polymer compound is 18-20°C for methanol and 44-44°C for ethanol, although it varies depending on the molecular weight.
6℃, 32-34℃ for n-propanol, 48-52℃ for isopropanol, 3℃ for n-butyl alcohol.
It is 2 to 35°C, and 31 to 35°C for isoamyl alcohol, and generally varies depending on the type of m alcohol.

〔Effect of the invention〕

The polymer compound of the present invention is a polymer compound that has not been described in any literature, and has a heat-sensitive property that undergoes a phase transition in an alcohol solvent such that it reversibly dissolves in m alcohols at high temperatures and becomes insoluble in m alcohols at low temperatures. It is a polymer compound and is different from conventionally known heat-sensitive polymers that undergo a phase transition in an aqueous solution. These polymers can be used, for example, in light shields for greenhouses, temperature sensors, toys, textile printing agents, displays, separation membranes, mechanochemical device materials, and the like.

Next, the present invention will be explained in more detail with reference to Reference Examples and Examples, but the present invention is not limited to these Examples in any way.

[Reference example]

2! In a Erlenmeyer flask, add triethylamine (100°80
g), 2-aminomethyl-1,3-dioxolane (
Add acrylic acid chloride (80 g) and benzene (980 m), cool on ice, keep the content at a temperature below 10°C, and add acrylic acid chloride (80 m) to benzene (
The solution was diluted with 20 m i') and slowly added dropwise from a dropping funnel over about 3 hours. After the dropwise addition was completed, the reaction solution was left in the refrigerator for a day and night to complete the reaction, and then filtered, and benzene was distilled off using a Roji Hisakou evaporator to obtain crude N-(1,
3-dioxolan-2-yl)acrylamide was concentrated. Then, it was recrystallized by a conventional method to obtain 113.58 g of a crystalline substance having a melting point of 70.8°C.

The infrared absorption spectrum of this material is shown in FIG.

Infrared spectrum NH- CH2=CH- 〉C=0 >CH- Tor analysis: Mass spectrum analysis: M+1 3293cm-' 1628cm- 1146cm-'1661cm-' 2955, 2918cm"' m/e = 158 OCH2 CH2=CHCO-= 55 CH2=CH= 27 From the above analysis results, N-(1,3-dioxolane-2
-yl) acrylamide.

[Example 1] A polymer compound of the vinyl monomer obtained in Reference Example was produced.

5.02 g of N-1,3-dioxolan-2-yl)acrylamide and 80 m of benzene in a 500 mf Erlenmeyer flask with a U-tube fitted with a capillary stopper! , 0.0419 g of azobisisobutyronitrile was added, and the mixture was kept at 60° C. for 1 hour while stirring under a nitrogen stream. Polymer precipitated as the polymerization progressed. After the reaction, the produced polymer compound was mixed with the reaction solvent in acetone, precipitated, and isolated. Yield: 2.61g.

The infrared absorption spectrum of this polymer compound is shown in FIG. By comparing the infrared absorption spectrum of the vinyl monomer with that of the polymer compound, it was confirmed that the vinyl group of 1628CM-1 disappeared and a polymer compound was formed.

The obtained polymer compound was made into an aqueous solution, and the viscosity was measured at 27°C using an Ubbelohde viscosity needle, and the intrinsic viscosity [η
] was sought. Intrinsic viscosity [η) = 0.59°.Thermal sensitivity characteristics were also investigated by measuring the light transmittance of the m-alcohol solution under thermal stimulation. The transmittance-temperature curve of the polymer compound alcohol solution of Example 1 is shown in FIG. Among these, the solid line is the data when cooling, and the broken line is the data when heating. That is, a polymer compound-hydric alcohol solution having a concentration of 1% by weight was adjusted, and the light transmittance at a wavelength of 500 nm was measured using a spectrophotometer with a temperature controller while cooling the solution at a cooling rate of 1° C./min. The transition temperature was determined from the temperature (TL) at which the light transmittance was 0.5 of the initial transmittance. These results are summarized in Table 1.

Table 1 [Example 2] 4.07 g of N-1,3-dioxolan-2-yl)acrylamide, 69 g of water at 1° 0.0512 g of ammonium sulfate was added, and the mixture was kept at 60° C. for 5 hours while stirring under a nitrogen stream to polymerize. As the polymerization progressed, a polymer was produced, resulting in a highly viscous aqueous solution. After the reaction, the mixture was dehydrated, mixed in acetone, precipitated, and isolated.

Yield: 4.04g.

Thereafter, the formation of a polymer compound was confirmed in exactly the same manner as in Example 1, the intrinsic viscosity [η] = 1.23 at 27°C in an aqueous solution, and the transition temperature of the alcohol solution was determined in exactly the same manner as in Example 1. These results are shown in Table 2.

Table 2

[Brief explanation of drawings]

FIG. 1 shows the infrared absorption spectrum of the vinyl monomer of Reference Example, and FIG. 2 shows the infrared absorption spectrum of the polymer compound of Example 1. FIG. 3 shows a transmittance-temperature curve in a 1% by weight alcohol solution of the polymer compound of Example 1 according to the method of the present invention. Patent applicant: Ken Sugiura, Director of the Agency of Industrial Science and Technology. Wave number + a60 12G building (cm-') 禦2 figure (am-')

Claims (2)

[Claims] (1) Formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ It consists of repeating units represented by 27
A heat-sensitive polymer compound having a molecular weight corresponding to an intrinsic viscosity [η] of 0.01 to 6.0 at a temperature of °C. (2) Formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Characterized by radical polymerization of the vinyl compound represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Consisting of repeating units represented by the aqueous solution 27 in
A method for producing a heat-sensitive polymer compound having a molecular weight corresponding to an intrinsic viscosity [η] of 0.01 to 6.0 at a temperature of °C.