JPH0242094B2 - - Google Patents

Description

[Detailed description of the invention]

[] BACKGROUND TECHNICAL FIELD OF THE INVENTION The present invention relates to a polymer having a five-membered ring and a double bond in the polymer main chain, which has excellent mechanical properties such as rigidity and shear strength, and has a high level of heat resistance. Currently, in the petrochemical industry, the _C5 fraction of naphtha decomposition products, which has 5 carbon atoms, is hardly used, and only a small amount of isoprene is used industrially as a raw material for synthetic rubber. Most of it is consumed as fuel. Prior Art Among these C ₅ fractions, the highest content is cyclopentadiene, which has high reactivity, so cyclopentene or
It is expected that it will be used as a new high value-added product such as norbornene derivatives. Among them, polymers produced by ring-opening polymerization using norbornene derivatives as monomers using metathesis catalysts are
Interesting as a new engineering plastic. In particular, 5-norbornene-2 produced by the Diels-Alder reaction of cyclopentadiene and acrylic acid.
- Carboxylic acid ring-opening polymers have the potential to become highly heat-resistant engineering plastics, but
Due to its strong polarity, it does not undergo ring-opening polymerization. Therefore, JP-A No. 56-65018 proposed a method of preparing a norbornene derivative as an ester compound, subjecting it to ring-opening polymerization, and then hydrolyzing it to obtain the desired ring-opening polymer of a 5-norbornene-2-carboxylic acid derivative. are doing. This polymer is a resin with high rigidity and an excellent balance of impact resistance and heat resistance, but in the housing field, structural material field, etc., it is desired to improve the rigidity and heat resistance of the resin itself. Therefore, the present inventors have developed a resin that meets the above-mentioned requirements by taking their resin manufacturing research one step further. [] Summary of the invention (1) The following general formula General formula Constituent unit (A) represented by and general formula (However, R ₁ is a hydrogen atom, an alkyl group or a phenyl group, R ₂ is a hydrogen atom or an alkyl group, R ₃ is an alkyl _group , represents an alkyl group) and satisfies the following requirements (a) to (c): (a) The intrinsic viscosity is 0.3 to 4.0. (b) The content of the above structural unit (A) in all structural units
Must be 90-100% by weight. (c) The trans content of double bonds in structural units (A) and (B) is 40% or more. Ring-opened polymers with such a structure can achieve a high level of rigidity that could not be achieved with conventional general-purpose engineering, and in particular, it is possible to obtain resin materials with excellent shear strength and excellent mechanical workability such as tapping. can. [] Detailed description of the invention Polymer The polymer of the present invention has the general formula Constituent unit (A) represented by and general formula It is a polymer basically composed of the structural unit (B) represented by the following, where R ₁ is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, preferably 1 to 8 carbon atoms, or a phenyl group, preferably a phenyl group. R ₂ represents a hydrogen atom or an alkyl group that is the same as or different from R ₁ , and R ₃ represents an alkyl group that is the same or different from R ₁ , and maintains the rigidity and moldability of these polymers. In order to do this, the intrinsic viscosity is
It is necessary to have from 0.3 to 4.0, particularly preferably from 0.4 to 3.0. If the intrinsic viscosity is less than 0.3, heat resistance, rigidity, and impact resistance will be poor, and if the intrinsic viscosity exceeds 4.0, moldability will deteriorate. Further, the content of the structural unit (A) in the above general formula needs to be 90 to 100% by weight of all the structural units. If the content of the above-mentioned structural unit (A) is less than 90% by weight, the level of rigidity and shear strength will be insufficient, and the level of heat resistance will decrease. Furthermore, it is necessary that the trans content of double bonds in the structural units (A) and (B) is 40% or more. If the transformer type is less than 40%, heat resistance and rigidity will deteriorate. Method for producing polymer The 5-norbornene-2-carboxylic acid ester derivative used in the present invention is generally synthesized by subjecting cyclopentadiene to an acrylic ester derivative or an α-alkyl-substituted acrylic ester derivative through a Diels-Alder reaction. Norbornene derivative monomers having these ester groups, such as methyl 5-norbornene-2-carboxylate, methyl 5-norbornene-2,2-carboxylate, ethyl 5-norbornene-2-carboxylate, 5-norbornene-2-carboxylic acid Octyl and the like are further easily ring-opening polymerized using metathesis catalysts described in JP-A-49-77999 and the like. As a metathesis catalyst, tungsten or molybdenum compounds are usually used as the transition metal component, and tungsten compounds are particularly preferred because they have high activity. Among these, tungsten halogen compounds are preferred. The organoaluminum component is not particularly limited, and for example, triethylaluminum, diethylaluminum monochloride, and ethylaluminum sesquichloride are used. As the third component species, oxygen-based ligands such as alcohols, nitrogen-based ligands such as pyridine, and phosphorus-based ligands such as triphenylphosphine are used. As the solvent, halogenated hydrocarbons, aromatic hydrocarbons, and halogenated aromatic hydrocarbons are used. In particular, aromatic hydrocarbons such as toluene and halogenated aromatic hydrocarbons such as chlorobenzene have high trans Suitable for obtaining esters. Atmospheric pressure is sufficient as the polymerization pressure, and the polymerization can also be carried out under increased pressure. The polymerization temperature used is in the range of -20℃ to 70℃, but if the temperature is too low, the activity will decrease significantly.
If the temperature is too high, the trans content will decrease and the desired product will not be obtained. Therefore, it is preferable to select the temperature within a range of about 0°C to 40°C. In order to obtain the target ring-opened polymer with a trans content of 40% or more, the amount of catalyst relative to the monomer must be increased, the polymerization temperature must be kept low, or alcohol or nitrogen-based compounds must be used as the third component. This is possible by selecting the order of magnitude. The polymer obtained by ring-opening polymerization has the general formula (However, R ₁ is a hydrogen atom, an alkyl group, or a phenyl group, R ₂ is a hydrogen atom or an alkyl group,
R ₃ represents an alkyl group. ) is a ring-opening polymer of a 5-norbornene-2-carboxylic acid ester derivative composed of repeating units represented by the formula, and preferably has an intrinsic viscosity of 0.4 to 4.0. However, since this ring-opened polymer itself is an ester substituted product, its heat resistance is low and it cannot be used practically as a heat-resistant resin. Therefore, the ring-opened polymer thus obtained is subjected to a hydrolysis treatment of the ester groups. Although there are no particular restrictions on the hydrolysis treatment, the following method is industrially advantageous. Dissolution of ring-opened heavy substance 5-norbornene-2 having the above ester group
- Ring-opening polymers of carboxylic acid esters are converted into ketones,
It is dissolved by using polar organic solvents such as tetrahydrofuran, dioxane, dimethylformamide, dimethyl sulfoxide, etc. These organic solvents dissolve the ring-opening polymer and are compatible with water, and by using these organic solvents, the ring-opening polymer described below can be industrially advantageously hydrolyzed. Can be done. The amount of these organic solvents to be used varies depending on the type and viscosity of the ring-opening polymer, but is generally 5 to 50 parts by weight per 1 part by weight of the polymer.
By adding this amount, a homogeneous solution can be obtained. First stage hydrolysis Next, 0.92 to 3 moles of alkali per mole of ester group units in the ring-opening polymer are dissolved in 10 to 100 parts by weight of water to 100 parts by weight of organic solvent, and this is used to open the ring. It is added sequentially to the polymer solution to hydrolyze the ester groups. As the alkali used, hydroxides of alkali metals or alkaline earth metals and salts of these with weak acids are used, and among these alkalis, sodium hydroxide, which is a hydroxide of alkali metals, is particularly used. Potassium hydroxide, lithium hydroxide and salts with weak acids, sodium carbonate, sodium acetate,
Potassium acetate and potassium carbonate are preferred. The amount of alkali used in the first and second hydrolysis steps is required to be at least 0.92 mol per mol of ester group unit in the ring-opening polymer. The alkali may be added in its entirety in the first stage hydrolysis step, or may be added in divided amounts in the first stage and second stage. However, in the first hydrolysis step, it is desirable to use 0.35 mol or more of alkali based on the ester group. If it is less than 0.35 mol, the hydrolysis rate will be low, making it difficult to dissolve the ring-opened polymer in water during the second-stage hydrolysis treatment. The alkali is generally added as an aqueous solution, but the concentration of the alkali is not particularly limited as long as the amount of water used falls within the above-mentioned ratio of organic solvent to water. Although the hydrolysis temperature is arbitrary between 40 and 200°C, the hydrolysis proceeds satisfactorily at 50 to 80°C. As the reaction progresses, the ring-opened polymer precipitates out of the reaction system and the reaction system becomes non-uniform. Second stage hydrolysis When the reaction system becomes non-uniform, water or aqueous alkaline solution is added. The organic solvent may be added while being heated to distill off the organic solvent, or may be added directly without being distilled off. The amount of water added must be at least 3 parts by weight per 1 part by weight of the polymer. If it is less than this, even if water or aqueous alkaline solution is added, a homogeneous solution will not be obtained. In addition, in a system in which the organic solvent is not distilled off, the total amount including the water added during the first-stage hydrolysis must be equal to or more than the amount of the organic solvent charged. There is no particular problem with the hydrolysis temperature as long as it is within the same range as the first stage hydrolysis. Neutralization Then, the carboxylic acid salt in the ring-opening polymer is converted into a carboxylic acid group by adding an acid, and the product is obtained as a precipitate. As the acid component, general acids such as hydrochloric acid, nitric acid, acetic acid, and sulfuric acid are sufficient, and the amount added is 1 to 10 equivalents relative to the carboxylic acid salt. There are no particular limitations on the concentration of the acid used. To obtain the product as a slurry, add 0.2 to 0.2 to
Add 0.7 equivalent, preferably 0.4 to 0.6 equivalent, stir for about 0.5 to 3 hours, and then gradually add the remaining acid component to obtain a good powder. In this neutralization reaction, if a predetermined amount of the acid component is added to the system at once, neutralization becomes possible, but the residual amount of alkali increases, the fluidity of the product decreases, and it is likely to be colored. Analysis/Measurement of Physical Properties The composition ratio of the product was quantified by infrared absorption spectroscopy. The trans content was quantified from the spectrum of the double bond region of ¹³ C-NMR spectroscopy. The intrinsic viscosity (ηs/C) was measured in tetrahydrofuran (concentration 0.1 g/g) at 30°C. Heat deformation temperature is determined by JIS K-7207-1974, Izotsu impact strength is determined by JIS K-7110-1971 (lap method of three 2 mm thick test pieces), and three-point bending rigidity is determined by JIS K-7110-1971.
7203-1973, the shear strength was measured based on K-7214, respectively. This will be explained in detail in Examples below. Example 1 After purging a dry flask with nitrogen, 400 parts by weight of toluene as a solvent and 100 parts by weight of 5-norbornene-2-carboxylic acid ester as a monomer were charged, and the liquid temperature was adjusted to 15°C. After that, 2.6 parts by weight of tungsten hexachloride was added, then diethylaluminum monochloride was added in an amount of 3 times the mole of tungsten hexachloride, and then n-butanol was added in an amount of 2 times the mole of tungsten hexachloride, and the mixture was left open for 10 hours. Ring polymerization was performed. After the polymerization reaction is completed,
15 to 3 times the volume of methanol to the toluene used in preparation.
Part by weight of concentrated hydrochloric acid was added, and this solution was attached to a flask for catalytic decomposition. Thereafter, the reprecipitation purification method was performed twice using tetrahydrofuran as a good solvent and methanol as a poor solvent, followed by drying to obtain 99 parts by weight of a polymer. The intrinsic viscosity of this polymer is 0.55
It was hot. The trans content was 55%. Next, 100 parts by weight of the ring-opening polymer is charged, followed by 1000 parts by weight of acetone, the temperature is raised to 56°C, and the polymer is completely dissolved under stirring. then 600
Fifty parts by weight of caustic potassium is dissolved in parts by weight of water, and this is gradually added to the acetone solution of the ring-opening polymer so as not to reduce the concentration of the reaction system. As ester hydrolysis progresses, the ring-opened polymer precipitates in the system. Next, 600 parts by weight of water was added to the system, and the reaction was continued for 1 hour while keeping the reaction temperature constant. After the addition of water, the precipitated ring-opened polymer dissolves in the solution and becomes a homogeneous system. Then, 94 parts by weight of acetic acid are diluted with 170 parts by weight of water and added to the aqueous solution of the ring-opening polymer. When half of the amount has been added, the addition is temporarily stopped, stirring is continued for 1 hour, and then the remaining amount is added, causing the ring-opened polymer to precipitate as a white powder. By passing this, the target 5-norbornene-2-
A ring-opened copolymer of carboxylic acid and methyl 5-norbornene-2-carboxylate was obtained. The physical property values of the product are shown in [Table 1]. Example 2 Under the conditions of Example 1, the amount of caustic potash was changed from 50 parts by weight.
The reaction was carried out in the same manner as in Example 1 except that the amount was reduced to 37 parts by weight. The physical property values of the product are shown in [Table 1]. Example 3 Caustic soda was used instead of the caustic potash used in Example 1.
Ester hydrolysis was carried out under the same charging conditions and reaction conditions as in Example 1, except that the amount was changed to 36 parts by weight. The physical property values of the product are shown in [Table 1]. Example 4 The methyl 5-norbornene-2-carboxylate monomer used in Example 1 was replaced with an octyl 5-norbornene-2-carboxylate monomer to obtain a ring-opened polymer. The product is 97 parts by weight and has an intrinsic viscosity of
0.62, and the trans content was 50%. Hydrolysis was carried out under the same charging conditions and reaction conditions as in Example 1. The physical property values of the product are shown in [Table 1]. Example 5 Instead of the 5-norbornene-2-carboxylic acid methyl monomer used in Example 1, 3-phenyl-5
-Norbornene-2-carboxylic acid methyl monomer was used to obtain a ring-opened polymer. The product weighed 37 parts by weight, had an intrinsic viscosity of 0.43, and a trans content of 53%. Hydrolysis was carried out under the same charging conditions and reaction conditions as in Example 1. The physical property values of the product are shown in [Table 1]. Example 6 Among the ring-opening polymerization conditions used in Example 1, when n-butanol was changed to 2,6-lutidine, a ring-opening polymer with an intrinsic viscosity of 0.65 and a trans content of 74% was obtained at 87 parts by weight. . Hydrolysis was carried out under the same charging conditions and reaction conditions as in Example 1. The physical property values of the product are shown in [Table 1]. Example 7 When the ring-opening polymerization conditions used in Example 1 were changed to 2.1 parts by weight of tungsten hexachloride, the polymerization temperature to 5°C, and the reaction time to 16 hours, the intrinsic viscosity was 1.2 and the trans content was 65 parts by weight. 43% ring-opened polymer was obtained. Hydrolysis was carried out under the same charging conditions and reaction conditions as in Example 1. The physical property values of the product are shown in [Table 1]. Comparative Example 1 Among the ring-opening polymerization conditions used in Example 1, tungsten hexachloride was changed to 0.3 parts by weight, the type of aluminum alkyl was changed to triethylaluminum, the solvent was changed from toluene to chlorobenzene, and the polymerization temperature was 40°C.
When the amount was changed to 98 parts by weight, a ring-opened polymer with an intrinsic viscosity of 1.4 and a trans content of 35% was obtained. Hydrolysis was carried out under the same charging conditions and reaction conditions as in Example 1. The physical property values of the product are shown in [Table 2]. Comparative Example 2 When 5.0 mol of 1,5-hexadiene was added to the ring-opening polymerization system of Example 1 as a molecular weight regulator based on tungsten hexachloride, a ring-opening polymer with an intrinsic viscosity of 0.28 and a trans content of 48% was obtained at 71 parts by weight. A combination was obtained. Hydrolysis was carried out under the same charging conditions and reaction conditions as in Example 1. The physical property values of the product are shown in [Table 2]. Comparative Example 3 Under the conditions of Example 1, the amount of caustic potash was changed from 50 parts by weight.
The reaction was carried out in the same manner as in Example 1 except that the amount was reduced to 30 parts by weight. The physical property values of the product are shown in [Table 2].

【table】

【table】

Claims (1)

[Claims] 1 The following general formula General formula Constituent unit (A) represented by and general formula (where R ₁ is a hydrogen atom, an alkyl group, or a phenyl group, R ₂ is a hydrogen atom or an alkyl group, and R ₃ is a
represents an alkyl group. ), and a polymer that satisfies the following requirements (a) to (c): (a) An intrinsic viscosity of 0.3 to 4.0. (b) The content of the above structural unit (A) is 90% of the total structural units.
~100% by weight. (c) The trans content of double bonds in structural units (A) and (B) is 40% or more.