KR100292635B1 - Instantaneously Self-Polymerizable Butadiene Derivatives and Process for Preparing Them - Google Patents

Abstract

Butadiene monomer of the following formula (1), butadiene polymer of the formula (2) and butadiene copolymer of the formula (3) and a method for preparing the same are disclosed.

In the formula,

R ₁ , R ₂ and R ₄ are the same or different, respectively, and are a cyano group, a carboxylate group (in Formula 1, a carboxylate group of C ₂ to C ₈ , and in Formulas 2 and 3, C ₁ to C ₈ Carboxylate group), sulfone group, formyl group, acetyl group, benzoyl group, phosphonyl group, amide group or phenyl group,

R ₃ is hydrogen or a methyl group, a C ₁ to C ₈ carboxylate group, sulfone group, formyl group, acetyl group, benzoyl group, phosphonyl group, amide group or phenyl group.

The butadiene derivatives can be easily prepared without the need for special initiators, catalysts and polymerization devices because of their strong reactivity, which is innovative in many functional polymer fields such as new processes, new polymers, coatings, carbon fiber precursors, instant adhesives, etc. It can be applied to.

Description

Instantaneously Self-Polymerizable Butadiene Derivatives and Process for Preparing Them}

The present invention relates to a very reactive butadiene derivative and a method for producing the same, and more particularly, to a highly reactive butadiene derivative and a method for producing the spontaneous self-polymerization by the presence of a polar substituent in the 1,3-position of butadiene .

In general, monomers in which a polar substituent such as a cyano group, an ester group, or a carboxylate group exist in a double bond of a vinyl monomer have a high polymerization reactivity, and in some cases, spontaneous radical polymerization or anionic polymerization is known to cause spontaneous radical polymerization or anionic polymerization without an initiator. have. Representative examples include alkyl cyanoacrylates currently widely used as raw materials for instant adhesives. This monomer can be prepared by several methods described in US Pat. Nos. 2,467,926, 2,721,858 and 3,463,804, etc. Unlike ordinary vinyl monomers, cyano and / or carboxylic acids on one side of the double bond Due to the polar substituents of the esters, spontaneous anionic polymerization proceeds instantaneously without an initiator.

In addition, when there are two polar substituents in the 1,1-position of butadiene, spontaneous anionic polymerization occurs, such as alkyl cyanoacrylate, to form a trans-1,4-butadiene polymer. For example, U.S. Patent Nos. 3,316,227 and 3,313,865 use 1-cyano-1-carbetoxy-1,3-butadiene synthesized by the reaction of ethyl cyanoacetate with acrolein as an additive to an instant adhesive. Impact resistance, peeling resistance, heat resistance and water resistance have been reported to increase.

Due to their strong reactivity, these monomers have a very high reactivity, making them simple to produce polymers without special initiators, catalysts, and polymerization devices, resulting in shortened processes, such as new processes, new polymers, coatings, carbon fiber precursors, and instant adhesives. It is anticipated that it will be able to be innovatively applied in the polymer field (see H. Mark, Chemtech, 614, 1976).

The inventors have already prepared butadiene monomers of the following formula (4) (see J. Polym. Sci., Polym. Chem. Ed., 19, 629-644, 1981), but yields are low and are too fast upon pyrolysis. Due to the polymerization at a high rate, not only monomers but also many polymers are produced, thereby limiting many applications.

In the formula,

R ₁ and R ₂ are the same or different, respectively, and are a cyano group or a C ₁ carboxylate group.

Accordingly, the present inventors have intensively studied to solve the above-mentioned problems, and as a result, they have developed butadiene derivatives which are spontaneously polymerized.

It is an object of the present invention to provide a highly reactive butadiene derivative which is instantaneously spontaneously polymerized by the presence of a polar substituent at the 1,3-position of butadiene, and a process for its preparation.

The present invention relates to a method for producing a butadiene monomer represented by the following Chemical Formula 1, and a butadiene monomer represented by the following Chemical Formula 1, using a carboxylate having a high carbon number to increase the yield of the monomer and to use a polymerization inhibitor in the pyrolysis process. will be.

<Formula 1>

In the formula,

R ₁ and R ₂ are the same or different, respectively, and are cyano group, C ₂ to C ₈ carboxylate group, sulfone group, formyl group, acetyl group, benzoyl group, phosphonyl group, amide group or phenyl group.

The present invention also relates to butadiene polymers and copolymers of the formulas (2) and (3).

<Formula 2>

<Formula 3>

In the formula,

R ₁ , R ₂ and R ₄ are the same or different, respectively, and are cyano group, C ₁ to C ₈ carboxylate, sulfone group, formyl group, acetyl group, benzoyl group, phosphonyl group, amide group or phenyl group ,

R ₃ is hydrogen or a methyl group, a C ₁ to C ₈ carboxylate group, sulfone group, formyl group, acetyl group, benzoyl group, phosphonyl group, amide group or phenyl group.

In addition, the present invention is the butadiene polymer of the formulas (2) and (3) characterized in that the butadiene monomer of the formula (1) spontaneously polymerized or copolymerized with an acrylic monomer in the absence of an initiator and a catalyst or using a radical initiator and A method for producing a copolymer.

Hereinafter, the present invention will be described in detail.

The butadiene monomer of the present invention is prepared using a carboxylate group having 2 (ethyl) to 8 (octyl) carbon atoms. This is because when the methyl group contains butadiene monomer is polymerized at a rapid rate during pyrolysis, the polymer is obtained a lot of the polymer yields a disadvantage in that the yield of the monomer is lowered, to prepare a butadiene monomer using a carboxylate group having 9 or more carbon atoms This is because the polymerization rate is too slow.

In Chemical Formulas 1 to 3 representing a highly reactive butadiene derivative, R ₁ , R ₂ and R ₄ are the same or different, respectively, and are a cyano group, a carboxylate group, a sulfone group, a formyl group, an acetyl group, which are electron attracting polar functional groups. , Benzoyl group, phosphonyl group, amide group or phenyl group is preferable. In Formula 3, R ₃ is preferably hydrogen, or a methyl group, cyano group, C ₁ to C ₈ carboxylate group, sulfone group, formyl group, acetyl group, benzoyl group, phosphonyl group, amide group or phenyl group. . These R ₁ to R ₄ is particularly preferably a carboxylate group that can control the polymerization rate, the carboxylate group of formula 1 is preferably a carboxylate group of C ₂ to C ₈ , carboxylate in the case of formulas 2 and 3 The group is preferably a C ₁ to C ₈ carboxylate group. Representative examples of the highly reactive butadiene monomers include 1-carboalkoxy-3-cyano-1,3-butadiene, 1-cyano-3-carboalkoxy-1,3-butadiene and 1,3-dicarboalkoxy- 1,3-butadiene, etc.

Butadiene monomer of the formula (1) has a polar substituent in the 1,3-position is more reactive than the existing 1,1-substituted butadiene can be spontaneously polymerized.

In addition, according to the present invention, the butadiene monomer of the formula (1) may be prepared using a polymerization inhibitor in the pyrolysis process to prevent instantaneous spontaneous polymerization as described above.

Polymerization inhibitors that can be used in the present invention include acidic compounds, for example thionyl chloride, sulfonic acid, carboxylic acid, HX (where X represents hydrogen acid including halogen, sulfuric acid, chloric acid) or Lewis acid, and the like. These may be used alone, or two or more thereof may be used together, and the amount thereof is preferably 10 to 1000 ppm. When the polymerization inhibitor is used less than 10 ppm, the polymer is produced, the yield of butadiene monomer is lowered, and when the polymerization inhibitor is used in excess of 1000 ppm, it is difficult to easily remove the polymerization inhibitor remaining after the reaction. Basically, the polymerization inhibitor is ideally easily removed during the polymerization reaction. Since thionyl chloride used in the present invention has a boiling point of 79 ° C., the thionyl chloride can be easily removed under vacuum, and is easily removed because it is decomposed into HCl and SO ₂ as gases at room temperature by reaction with moisture.

The (co) polymers of Formulas (2) and (3) are 5 to 90% by weight of the butadiene monomer of Formula 1, based on the total amount of the (co) polymer, in the absence of an initiator and a catalyst or at a temperature between room temperature and 100 ° C. May be prepared by spontaneous polymerization or copolymerization with an acrylic monomer. In the case of (co) polymerization, if the content of butadiene monomer is less than 5% by weight, the properties of the desired (co) polymer do not appear, whereas if the content of butadiene monomer is more than 90% by weight, the manufacturing cost is too expensive for general use. There is this.

Acrylic monomers that can be used in the present invention include alkyl cyanoacrylate, methacrylate, acrylonitrile, and the like, and radical initiators include 2,2'-azobisisobutyronitrile (AIBN) or benzoyl per Oxides (BPO) and the like. Butadiene monomer of formula (1) can be spontaneous polymerization without the use of any initiator or catalyst at room temperature, it is possible to prepare a butadiene polymer of the formula (2) of a relatively high molecular weight. In addition, the monomer may be dissolved in a general organic solvent and then polymerized using a radical initiator such as AIBN or BPO at 100 ° C. or lower. The prepared polymer showed a difference in solubility in general organic solvents according to the type of substituents and the position of substitution, and was generally well dissolved in a polar solvent such as dimethylformamide. Thus, the butadiene derivatives according to the invention can be used as such or in combination with additives as polymer materials such as instant adhesives, carbon fibers and the like. For example, one of the monomers, 1-carbomethoxy-3-cyano-1,3-butadiene, is well copolymerized with ethyl cyanoacrylate, which is used as an instant adhesive, and the resulting copolymer is added to the main chain. Having double bonds has shown a significant improvement in flexibility and thermal stability, a disadvantage of conventional instant adhesives. In addition, another monomer, 1,3-dicyano-1,3-butadiene, is well copolymerized with acrylonitrile used as carbon fiber, and the resultant copolymer has a double bond in the main chain, thereby Since the critical ring formation temperature at the previous step is significantly lower than conventional acrylonitrile polymers, rings can be formed at lower temperatures than conventional methods. Moreover, homopolymers of 1,3-dicyano-1,3-butadiene are advantageously formed at lower temperatures when using these monomers, because the ring forms at 230 ° C., about 100 ° C. or lower than the acrylonitrile polymer. Can be prepared. Therefore, the butadiene derivative prepared according to the present invention can be applied as various functional polymer raw materials, such as instant adhesive, carbon fiber.

Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by these Examples.

<Example>

<Example 1>

Preparation of 1-carbetoxy-3-cyano-1,3-butadiene monomer

The norbornene adduct was prepared by diels-alder reaction of cyclopentadiene and acrylonitrile, followed by induction of anion with lithium diisopropylamide, followed by ethyl formate reaction. A derivative was synthesized, and 2-carbetoxyvinyl-2-cyano-5-norbornene was synthesized by reacting carbetoxymethylenetriphenylphosphorane by a Wittig reaction. Finally, the temperature of the pyrolysis device made of quartz glass tube was raised to 450 ° C., and then the internal pressure was 0.67 millibars (0.5 mmHg) with a vacuum pump, followed by the synthesis of 2-carbetoxyvinyl-2-cyano-5-norbor. 15 g of nene was dissolved in 120 ml of benzene, and 300 ppm of thionyl chloride was added to the resulting solution, and then slowly added dropwise to the column in the pyrolysis apparatus to prepare a 1-carbetoxy-3-cyano-1,3-butadiene monomer. The monomer thus produced was a crystalline solid, with a yield of 70%, a melting point of about 50 ° C. and no polymer at all. The chemical structure of the obtained monomer was confirmed by IR and NMR analysis.

IR (CCl ₄ solution, cm ⁻¹ ): 2237 (CN), 1729 (CO ₂ R), 975 (CH = CH).

¹ H-NMR (CDCl _3, δ): 7.0 (q, 2H), 6.1 (d, 2H).

The resulting monomers were dissolved in carbon tetrachloride and stored.

Comparative Example 1

Preparation of 1-carbomethoxy-3-cyano-1,3-butadiene monomer

1-Carbomethoxy- in the same manner as in Example 1, except that carbomethoxymethylenetriphenylphosphorane was used instead of carbetoxymethylenetriphenylphosphorane in the Wittich reaction and thionyl chloride was not used during pyrolysis. 3-Cyano-1,3-butadiene monomer was prepared. The chemical structure of the obtained monomer was almost the same as in Example 1, the yield was relatively low (40%), and the polymer contained 50%.

Comparative Example 2

Preparation of 1-carbetoxy-3-cyano-1,3-butadiene monomer

A 1-carbetoxy-3-cyano-1,3-butadiene monomer was prepared in the same manner as in Example 1, except that thionyl chloride was not used during pyrolysis. The chemical structure of the obtained monomer was the same as in Example 1, the yield was relatively low (40%), of which 30% of the polymer was included.

<Example 2>

Preparation of 1-Carbooctoxy-3-cyano-1,3-butadiene monomer

1-Carbooctoxy-3-cyano-1,3-butadiene in the same manner as in Example 1 except that carbooxytoxymethyltriphenylphosphorane was used in place of carbetoxymethylenetriphenylphosphorane in the Wittich reaction. Monomers were prepared. The obtained monomer showed almost the same yield as Example 1, and the chemical structure was similar.

<Example 3>

Preparation of 1,3-dicyano-1,3-butadiene monomer

A 1,3-dicyano-1,3-butadiene monomer was prepared in the same manner as in Example 1, except that cyanomethylenetriphenylphosphorane was used instead of carbetoxymethylenetriphenylphosphorane in the Wittich reaction. The monomer thus produced was a crystalline solid, with a yield of 80%, a melting point of 79 ° C., and no polymer at all. The chemical structure of the obtained monomer was confirmed by IR and NMR analysis.

IR (KBr, cm ⁻¹ ): 2235 (CN), 1625 (CO ₂ R), 970 (CH = CH).

¹ H-NMR (CDCl _3, δ): 7.1 and 5.9 (q, 2H), 6.4 and 6.3 (d, 2H).

The resulting monomers were dissolved in carbon tetrachloride and stored.

<Example 4>

Preparation of 1,3-dicarbutoxy-1,3-butadiene monomer

A 1,3-dicarbethoxy-1,3-butadiene monomer was prepared in the same manner as in Example 1 except that methyl acrylate was used instead of acrylonitrile in the Diels-Alder reaction. The obtained monomer showed almost the same yield as Example 1, and the chemical structure was similar.

Example 5

Preparation of Poly (1-Carbomethoxy-3-cyano-1,3-butadiene) Polymer

The 1-carbomethoxy-3-cyano-1,3-butadiene monomer was left in air at room temperature without adding an initiator to allow polymerization to proceed quantitatively, and the yield of the white powder polymer obtained by precipitation of the product in hexane was 100%. It was. The chemical structures of the polymers obtained were analyzed by IR and NMR, and the viscosity and thermal properties (glass transition temperature (Tg) and pyrolysis temperature (Td)) were evaluated by viscometer and differential scanning calorimetry (DSC), respectively.

IR (KBr, cm ⁻¹ ): 2221 (CN), 1739 (CO ₂ R).

¹ H-NMR (CDCl _3, δ): 6.2 (d, 1H), 3.7 (s, 4H), 2.8 (b, 2H).

Viscosity (CHCl ₃ , δ): 0.35; Tg: 57 ° C .; Td: 254 ℃

The resulting polymer showed a relatively high molecular weight, and it was found that the flexibility and heat resistance were significantly increased than the ethyl cyanoacrylate polymer (Tg: 135 ° C; Td: 148 ° C) used as the instant adhesive.

<Example 6>

Preparation of Poly (1-Carbetoxy-3-cyano-1,3-butadiene) Polymer

The 1-carbetoxy-3-cyano-1,3-butadiene monomer was left at 55 ° C. under nitrogen without adding an initiator to proceed polymerization quantitatively, and the yield of the white powder polymer obtained by precipitating the product in hexane was 100%. It was. The chemical structure, viscosity and thermal properties of the resulting polymer were similar to Example 5.

<Example 7>

Preparation of Poly (1,3-dicyano-1,3-butadiene) Polymer

The 1,3-dicyano-1,3-butadiene monomer was dissolved in benzene under nitrogen, a small amount of AIBN was added and the reaction was carried out at 60 ° C. for 6 hours to allow the polymerization to proceed quantitatively, and the product was precipitated in hexane. The yield of powdered polymer was 100%. The chemical structure and viscosity of the polymer obtained were similar to Example 5, and the ring formation temperature analyzed by DSC was 208 ° C., which is much lower than the acrylonitrile polymer (293 ° C.) used as the carbon fiber precursor, advantageously at low temperatures. Fibers can be produced.

<Example 8>

Preparation of Poly (1-Carbomethoxy-3-cyano-1,3-butadiene / ethyl cyanoacrylate) copolymer

0.5 g of 1-carbomethoxy-3-cyano-1,3-butadiene was dissolved in 1.5 g of ethyl cyanoacrylate under nitrogen, and then allowed to stand at room temperature without adding an initiator to allow polymerization to proceed quantitatively. The yield of white powdery polymer obtained by precipitation in hexane was 100%. The chemical structures of the resulting polymers were analyzed by IR and NMR, and the viscosity and thermal properties were evaluated by viscometer and DSC, respectively.

IR (KBr, cm ⁻¹ ): 2222 (CN), 1746 (CO ₂ R).

¹ H-NMR (CDCl _3, δ): 6.2 (d, 1H), 4.2 (s, 2H), 3.7 (s, 4H), 2.8 (b, 2H), 1.4 (s, 3H).

Viscosity (CHCl ₃ ): 0.32; Tg: 115 ° C .; Td: 179 ° C.

The resulting copolymer showed a relatively high molecular weight, and it was found that flexibility and heat resistance were increased more than the ethyl cyanoacrylate polymer (Tg: 135 ° C; Td: 148 ° C) used as the instant adhesive.

Example 9

Preparation of Poly (1,3-dicyano-1,3-butadiene / acrylonitrile) Copolymer

0.5 g of 1,3-dicyano-1,3-butadiene was dissolved in 5 g of acrylonitrile under nitrogen, diluted with benzene, 0.01 g of BPO was added, and then reacted at 80 ° C. for 24 hours for polymerization. The yield of the white powdery polymer obtained by precipitating the product in ethanol was 100%. The chemical structure and viscosity of the obtained copolymer were similar to those of Example 8, and the ring formation temperature analyzed by DSC was 235 ° C, which is advantageously lower than acrylonitrile polymer (293 ° C), which is used as a carbon fiber precursor. Carbon fibers can be produced.

Butadiene derivatives prepared according to the present invention can be prepared simply by the polymer without the need for special initiators, catalysts and polymerization devices because of their strong reactivity, such as new processes, new polymer products, coatings, carbon fiber precursors, instant adhesives, etc. It can be innovatively applied to functional polymer field.

Claims (10)

Butadiene copolymer of the formula (3). <Formula 3> In the formula, R ₁ , R ₂ and R ₄ are the same or different, each being a cyano group or a C ₁ to C ₈ carboxylate group, R ₃ is hydrogen or a methyl group, cyano group or C ₁ to C ₈ carboxylate group. A method for producing a butadiene monomer of the formula (1) by a pyrolysis step, wherein a polymerization inhibitor of 10 to 1000 ppm is used in the pyrolysis step. <Formula 1> In the formula, R ₁ and R ₂ are the same or different, respectively, and are cyano groups or C ₂ to C ₈ carboxylate groups. 3. The 1-carboalkoxy-3-cyano-1,3-butadiene, 1-cyano-3-carbo of claim 2, wherein the butadiene monomer is alkyl of carboalkoxy is C ₂ to C ₈ alkyl. A process for producing alkoxy-1,3-butadiene or 1,3-dicarboalkoxy-1,3-butadiene. 4. The method of claim 2 or 3, wherein the polymerization inhibitor is selected from the group consisting of thionyl chloride, sulfonic acid, carboxylic acid, HX (where X represents hydrogen acid including halogen, sulfuric acid or chloric acid) and Lewis acid which are acidic compounds. A process for producing at least one compound. Spontaneously homopolymerizing 5 to 90% by weight of butadiene monomer of formula (1) based on the total amount of polymer or copolymer in the absence of initiator and catalyst or using a radical initiator at a temperature from room temperature to 100 ° C, or an acrylic monomer Method for producing a butadiene polymer or copolymer of the formula (2) and 3 characterized in that the copolymerization with. <Formula 1> <Formula 2> <Formula 3> In the formula, R ₁ , R ₂ and R ₄ are the same or different, respectively, and are a cyano group or a carboxylate group (in Formula 1, a carboxylate group of C ₂ to C ₈ , and in Formulas 2 and 3, C ₁ to C ₈ Carboxylate group), R ₃ is hydrogen or a methyl group, cyano group or C ₁ to C ₈ carboxylate group. (Correction) The 1-carboalkoxy-3-cyano-1,3-butadiene and 1-cyano-3 of claim 5, wherein the butadiene monomer is alkyl of carboalkoxy is C ₂ to C ₈ alkyl. -Carboalkoxy-1,3-butadiene or 1,3-dicarboalkoxy-1,3-butadiene. 7. A process according to claim 5 or 6 wherein the acrylic monomer is selected from the group consisting of alkyl cyanoacrylates, methacrylates and acrylonitrile. The process according to claim 5 or 6, wherein the radical initiator is 2,2'-azobisisobutyronitrile (AIBN) or benzoyl peroxide (BPO). The method of claim 2, wherein the monomer is usable as an instant adhesive when used by itself or as an additive. The method of claim 2, wherein the monomer is usable as carbon fiber when used as such or as an additive.