JPH0780996B2 - Method for producing impact resistant crosslinked polymer molding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION a. Field of Industrial Application The present invention is a crosslinked polymer in which a metathesis-polymerizable monomer is poured into a molding mold in the presence of a metathesis polymerization catalyst system, and bulk polymerization and molding are performed in the mold at the same time. The present invention relates to a method for producing a molded product. More specifically, the present invention relates to improving the impact resistance and heat resistance of a crosslinked polymer molded product by allowing a specific liquid rubber to coexist during the polymerization.

b. Prior Art It is known that cyclic olefins are opened by a metathesis polymerization catalyst system to give crosslinked polymers.

Therefore, a method is proposed in which a monomer having two metathesis-polymerizable groups, such as dicyclopentadiene, that can be obtained at low cost is poured into a mold in a liquid state, and palk-polymerized in the mold, and molding is performed in one step at the same time as polymerization. (See, for example, JP-A-58-129013).

According to such a method, a large-sized molded product can be obtained by using an inexpensive mold, so that it can be used in a wide range of applications. However, there are many applications in which such a large molded product is required to have good impact resistance. However, in general, the impact resistance is often insufficient in the metathesis-polymerizable monomer as described above, particularly in the crosslinkable monomer. As a method for improving this, a method of molding a polymer molded product in the presence of a rubber soluble in a monomer and a method of adding a plasticizer have been proposed. The method of adding a plasticizer generally has a problem of blooming of the added plasticizer, and it cannot be said to be a sufficient method. On the other hand, the method of adding rubber can be said to be an effective method because a considerably large effect is recognized even if it is added in a small amount. However, the addition of such a rubber greatly increases the viscosity of the reactive solution of the monomer. On the other hand, it is necessary to have a low viscosity in order to efficiently and efficiently pour the reactive solution of the monomer into the template. In such a method, even a reaction injection molding method using high-pressure collision mixing capable of handling the most viscous monomer liquid generally only handles a viscosity of several poises, and a resin for impregnating and solidifying a monomer premix into glass fiber or the like. It was found that methods such as transfer molding require lower viscosity, and the amount that can dissolve the rubber component is extremely limited. That is, it has been found that in the method of adding a general rubber, the addition amount is limited due to the viscosity of the monomer liquid, and it is not possible to sufficiently cope with a certain use.

Therefore, the present inventor has arrived at the present invention as a result of earnest research on a method for obtaining a polymer molded product by metathesis polymerization which has impact resistance even in applications requiring such low viscosity.

c. Structure of the Invention That is, the present inventor has focused on liquid rubber. General rubber is a polymer substance that has a number average molecular weight of several hundred thousand or more before vulcanization and is solid at room temperature. On the other hand, the liquid rubber basically has the same structural unit, but its molecular weight is not constant depending on its structure, but generally it is liquid at room temperature of about 1000 to several hundreds of thousands. Such a liquid rubber generally has a functional group such as a hydroxyl group, a carboxyl group and an amino group at the molecular weight terminal, and is a telechelic polymer (tele
Chelic polymer) is called solid polymer by cross-linking and chain extension using its functional groups.

However, such a telechelic polymer cannot be used with this polymerization catalyst system because such functional groups have a strong poisoning effect on the metathesis polymerization catalyst system. Therefore, when a liquid rubber containing no functional group at the end and having a certain degree of unsaturated bond in the chain was used, the polymerization was not hindered and a part of the unsaturated bond participated in the metathesis polymerization reaction and thus the crosslinked structure was It has been found that a crosslinked polymer molded product having not only the effect considered to be taken into consideration, that is, impact resistance but also improved heat resistance can be obtained.

That is, the present invention is a method for bulk polymerization of a metathesis polymerization monomer in the presence of a metathesis polymerization catalyst system to obtain a crosslinked polymer molding, wherein the polymerization is a non-telechelic liquid having an unsaturated bond of 20 to 40% by weight. A method for producing an impact-resistant crosslinked polymer molded article, characterized in that the liquid rubber is used in the coexistence of the rubber, and the liquid rubber is used in a range of 5 to 20% by weight based on the total amount of the metathesis polymerizable monomer. is there.

In the present invention, (a) a reactive solution of a methesis polymerizable monomer containing a catalyst component of a metathesis polymerization catalyst system (solution A) and (b) reactivity of a metathesis polymerization monomer containing an activator component of a metathesis polymerization catalyst system. In a combination of reactive solutions consisting of at least a solution (solution B), the metathesis-polymerizable monomer obtained by combining the solution A and the solution B is a non-monomer having 2 to 40% by weight of unsaturated bonds.
Contains a telechelic liquid rubber, and the liquid rubber is 5 to 20% by weight based on the total amount of the metathesis polymerizable monomer.
It is possible to use a combination of the reactive solutions characterized by containing in the range of.

As described above, the liquid rubber used in the present invention is a liquid at room temperature, and therefore, the processing steps that are performed on ordinary rubber, such as calendering and milling, are impossible. Therefore, since the range of liquid is different depending on its constitutional unit, the molecular weight of the liquid rubber to be used cannot be specified unconditionally, but it is generally about 1000 or more and generally 100,000 or less except for special cases. Is used. In the case of poly-cis-1,4-isoprene, one having a particularly large molecular weight can be used, and it is generally tens of thousands or more.
The range of 10,000 is used.

Further, the liquid rubber used in the present invention needs to contain an unsaturated bond to a certain extent or more, and therefore, in general, a diene rubber itself is preferably used.
A hydrogenated product of these diene rubbers, an isobutylene-diene polymer, or an ethylene-propylene-diene terpolymer can be used, but it is necessary to contain an unsaturated bond to a certain degree or more, and generally an iodine value is used. It is preferably 10 or more, particularly 25 or more.

Specific examples of these liquid rubbers include polycis-1,
4-isoprene, polycis-1,4-butadiene, poly-1,
2-butadiene, polystyrene-butadiene, partial water additives of these rubbers, polyethylene-butadiene, polypropylene-butadiene, polyethylene-propylene-
Examples thereof include diene-polymer, polyacrylonitrile butadiene, and polyisobutylene-diene.

The liquid rubber in the present invention is a non-telechelic (non-t
elechelic), and the word non-telechelic means not only the terminal but also the functional group such as hydroxyl group, carboxyl group, amino group, etc. in addition to the terminal, and the activity of the metathesis polymerization catalyst system. It should be understood that it does not contain a polar proton-containing group that inhibits The liquid rubber can be used regardless of the polymerization method such as ionic polymerization or radical polymerization, but in the case of radical polymerization, in the case of emulsion polymerization frequently performed, the emulsifier mixed in the polymer is metathesis. It is not preferable because it inhibits the activity of the polymerization catalyst system.

Among the liquid rubbers mentioned above, polycis-1,4-isoprene, polycis-1,4-butadiene and poly-1,2-butadiene are particularly suitable.

The liquid rubber in the present invention is used in the range of 2 to 40% by weight based on the total amount of the metathesis polymerizable monomer. A more preferred range of use is 3 to 30% by weight, especially 5
-20% by weight is preferred. However, this is only from a general point of view, and depends on the monomer used, the liquid comb, the required degree of impact resistance, etc., and the optimum addition amount should be determined by experiments.

In the conventional polymerization of metathesis-polymerizable monomers, the solid rubber is used in a ratio of 10 even in reaction injection molding in which a rubber having a relatively low viscosity is used and a high-viscosity liquid is acceptable due to restrictions such as usable viscosity during molding as described above. Although it was not more than 7% by weight, generally not more than 7% by weight, it is possible to add the liquid rubber in the above wide range.

On the other hand, with the liquid rubber as described above, as the metathesis polymerizable monomer used for forming the molded product, any compound such as one capable of bulk polymerization by metathesis polymerization to give a molded product may be used, but generally metathesis polymerizable Those containing 1 to 4 cycloalkene groups are used. Those having a norbornene-type bond are particularly preferable. Hydrocarbons are particularly preferable, and a specific example is dicyclopentadiene. Dihydrodicyclopentadiene, cyclopentadiene-methylcyclopentadiene co-dimer, 5-ethylidene norbornene, 5-
Vinyl norbornene, norbornene, 5-cyclohexenyl norbornene, 1,4-methano-1,4,4a, 5,6,7,8,8a-
Octahydronaphthalene, 1,4,5,8-dimethano-1,4,4a,
5,6,7,8,8a-octahydronaphthalene, 6-ethylidene-1,4,5,8-dimethano-1,4,4a, 5,6,7,8,8a-heptavidronaphthalene, 1, 4,5,8-Dimethano-1,4,4a, 5,8,8a-hexahydronaphthalene, tricyclo [8,2,1,0] trideca-5,11-diene, norbornadiene, 5-phenylnorbornene, ethylene Examples include bis (5-norbornene). Particularly preferred is dicyclopentadiene or a monomer mixture containing 50% or more thereof.

Further, if necessary, a metathesis polymerizable monomer containing a polar group having a different element such as oxygen or nitrogen can also be used. Such a metathesis-polymerizable monomer also preferably has a norbornene structural unit, and as the polar group,
An ester group, an ether group, a cyano group, an N-substituted imide group and the like are preferable.

Such a polar group has, as a Lewis base, an action of controlling the initiation of the metathesis polymerization reaction, and also has an effect of introducing a polar group into the polymer molded product thus produced, so that the necessity of those actions is satisfied. It is suitably used depending on the situation.

Examples of such polar monomers include (5-norbornenyl)
Methyl-phenyl ether, bis [(5-norbornenyl) methyl] ether, 5-methoxycarbonylnorbornene, 5-methoxycarbonyl-5-methyl-norbornene, 5-[(2-ethylhexyloxy) carbonyl] norbornene, ethylene-bis (5-norbornenecarboxylate), 5-cyanonorbornene, 6-cyano-1,4,5,8-dimethano-1,4,4a, 5,6,7,8,8a-octahydronaphthalene, N-butyl Nadic acid imide, 5
Examples thereof include-(4-pyridyl) -norbornene.

Further, a halogen-containing / metathesis polymerizable monomer can be used for improving flame retardancy and softening temperature. Specific examples of such a monomer include 5-chloronorbornene,
5-bromonorbornene, 5,5,6-trichloronorbornene, 5,5,6,6-tetrachloronorbornene, 5,6-dibromonorbornene, 5- (2,4-dibromophenyl)
Norbornene etc. can be mentioned.

It is preferable that all the metathesis polymerization monomers as described above have a content of impurities that inhibit the metathesis polymerization catalyst as small as possible.

The metathesis polymerization catalyst system used to obtain polymer moldings in the present invention generally comprises two components, a catalyst component and an activator component, as is known.

However, the metathesis polymerization reaction is generally an exothermic reaction, and once the polymerization is started, the system is further heated to accelerate the reaction.

Therefore, as described above, two solutions, that is, a solution mainly composed of a monomer and a catalyst component (solution A) and a solution mainly composed of a monomer and an activator component (solution B) are prepared in advance and subjected to collision mixing (RIM method). ) Or a static mixer, rapid mixing, immediate injection into a mold, shaping, and curing in a mold can be preferably used. In that case, the composition of the monomer does not have to be the same in both liquids, and can be arbitrarily changed depending on the function of the monomer. The addition amount of the liquid rubber can be changed depending on the two liquids, but in the reaction injection molding method, it is generally more preferable that the two liquids have the same viscosity because mixing is effectively performed.

As another method for obtaining a polymer molded product, a Lewis base that acts as a regulator that delays the initiation of metathesis polymerization as described above, or a metathesis polymerization monomer having such a Lewis base is added to delay the initiation of polymerization and preliminarily generate it. A method of injecting the prepared premix into the mold, that is, a method of resin injection can be used. In this case, it is advantageous to obtain a fiber-reinforced molded product by placing a glass fiber mat or the like in the mold in advance.

Salts such as halides of tungsten, rhenium, tantalum, molybdenum and the like are used as a catalyst component in the metathesis polymerization catalyst system, but a tungsten compound is particularly preferable. As such a tungsten compound, tungsten halide, tungsten oxyhalide and the like are preferable, and more specifically, tungsten hexachloride, tungsten oxychloride and the like are preferable. Further, organic ammonium tungstate or the like can also be used. It has been found that such a tungsten compound immediately starts cationic polymerization when added directly to the monomer, which is not preferable. Therefore, the tungsten compound is preferably suspended in an inert solvent such as benzene, toluene, chlorobenzene or the like in advance and solubilized by adding a small amount of an alcohol compound or a phenol compound before use.

Further, as described above, in order to prevent undesired polymerization, it is preferable to add about 1 to 5 mol of Lewis base or chelating agent to 1 mol of the tungsten compound. Examples of such additives include acetylacetone, acetoacetic acid alkyl esters, tetrahydrofuran, and benzonitrile. The copolymerizable polar monomer used in the present invention may be a Lewis base itself as described above, and may have its action even if the above compound is not added.

Thus, the monomer solution containing the catalyst component (solution A) is
It has practically sufficient stability.

On the other hand, the activator component in the metathesis polymerization catalyst system is preferably an organometallic compound centered on an alkylated compound of a metal of Group I to Group III of the Periodic Table, particularly tetraalkyltin, an alkylaluminum compound, an alkylaluminum halide compound, Specific examples thereof include diethylaluminum chloride, diethylaluminum chloride, trioctylaluminum, dioctylaluminum aodide, and tetrabutyltin. The other solution (corresponding to solution B) is formed by dissolving the organometallic compound as the activator component in the raw material monomer.

In the present invention, basically, a crosslinked polymer molded product can be obtained by mixing the solution A and the solution B, but with the above composition as it is, the polymerization reaction is started very quickly, Curing may occur before it sufficiently flows into the molding mold, which often causes a problem. As described above, it is preferable to use an activity modifier for that purpose.

As such a regulator, Lewis bases are generally used, and ethers, esters, nitriles and the like are used. Specific examples include ethyl benzoate, butyl ether, diglyme and the like. Such a regulator is generally used by adding it to the solution side of the component of the activator of the organometallic compound. When a monomer having a Lewis base group is used as described above, it can also serve as a regulator.

The amount of the metathesis polymerization catalyst system used is, for example, when a tungsten compound is used as the catalyst component, the ratio of the tungsten compound to the raw material monomer is about 10 on a molar basis.
When the activator component is an alkylaluminum, the ratio of the aluminum compound to the raw material monomer is about 100 on a molar basis. Around 1 to about 2000 to 1, preferably about 200 to 1 to about 500 to 1 is used. Further, as described above, the masking agent and the regulator can be appropriately adjusted and used depending on the amount of the catalyst system used by experiments.

The crosslinked polymer molded product according to the present invention may further contain various additives in order to improve or maintain its properties in practical use. Such additives include fillers, pigments, antioxidants, light stabilizers, flame retardants, polymer modifiers and the like. Since such an additive cannot be added after the crosslinked polymer of the present invention is formed, it is necessary to add the additive to the above-mentioned raw material solution in advance.

The easiest method is the solution A and the solution B.
Although it is possible to cite a method of adding it to either or both of them in advance, in that case, the catalyst component or the activator component having strong reactivity in the liquid does not react to a certain extent with practical use, and It must not interfere with polymerization. In any case, if the reaction is unavoidable but does not substantially inhibit the polymerization even if it exists, it is also possible to mix it with the monomer to prepare the third liquid, and to use the mixture immediately before the polymerization. . Further, in the case of a solid filler, both components are mixed, and immediately before starting the polymerization reaction or while polymerizing, those having a shape capable of sufficiently filling the voids, in the molding mold, It is also possible to fill it.

The reinforcing material or filler as an additive is effective in improving the bending modulus. Examples of such a material include glass fiber, mica, carbon black, and wollastonite. Those obtained by surface-treating these with a so-called silane coupler can also be suitably used.

In addition, it is preferable to add an antioxidant to the crosslinked polymer molded product of the present invention, and therefore it is desirable to add a phenol-based or amine-based antioxidant to the solution in advance. Specific examples of these antioxidants include 2,6-di-t-butyl-p-cresol and N, N'-diphenyl-
p-phenylenediamine, tetrakis [methylene (3,5
-Di-t-butyl-4-hydroxycinnamate)] methane and the like.

The polymer molded product of the present invention is characterized by improving flexibility and impact resistance and, in some cases, heat resistance by adding liquid rubber. By using it in the form of such a liquid rubber, a wider range of addition amount is possible than in the case of ordinary solid rubber, but the solid elastomer is also small in amount within a range not impairing the characteristics of the present invention, generally 5 Amounts of less than or equal to 5% by weight, and generally less than or equal to 3% by weight can be used in combination. Examples of the elastomer used for this purpose include styrene-butadiene-styrene triblock rubber, styrene-isoprene-styrene triblock rubber, polybutadiene, polyisoprene, butyl rubber, ethylene propylene-diene terpolymer, and nitrile rubber.

The polymer molded product of the present invention is produced by simultaneously performing polymerization and molding as described above.

As the molding method, as described above, the resin injection method in which the catalyst system and the monomer mixture are mixed in advance into the mold, the solution A and the solution B in which the catalyst system is divided into two are collided at the head portion. It is possible to adopt the RIM method in which it is mixed and poured into the mold as it is. In either case, the injection pressure into the mold can be relatively low, and thus inexpensive molds can be used.

Further, when the polymerization reaction in the mold starts, the temperature in the mold rapidly rises due to the reaction heat, and the polymerization reaction ends in a short time. Unlike the case of polyurethane-RIM, it is easy to release from the mold, and a special release agent is often unnecessary.

Since the molded product has an oxide layer on the surface, it has good adhesion to commonly used paints such as epoxy and polyurethane.

d. Effects of the invention The molded product thus obtained has improved impact resistance and heat resistance compared to conventional products, and is a member of various transportation equipment including automobiles, a housing for electric and electronic equipment. Such,
It can be used for a wide range of applications, mainly for large moldings.

e. Examples Hereinafter, the present invention will be described in detail with reference to Examples. It should be noted that the embodiment is for the purpose of explanation, and the present invention is not limited to this.

Examples 1 to 10 and Comparative Example Commercially available dicyclopentadiene (DCP) was purified by distillation in a nitrogen stream under reduced pressure. Purified dicyclopentadiene has a melting point
The purity was 99% or higher when measured by gas chromatography at 33.6 ℃.

The liquid rubber used was that shown in Table 1 below.

The liquid rubber and DCP were mixed at a ratio shown in Table 2 below to obtain a monomer mixture. The melt viscosity at 30 ° C. was measured with a rotational viscometer and is shown in Table 2.

[Preparation of Catalyst Component Solution] 20 g of tungsten hexachloride was added to 70 ml of dry toluene under a nitrogen stream, and then a solution of 21 g of nonylphenol and 16 ml of toluene was added to prepare a 0.5 M tungsten-containing catalyst solution. On the other hand, nitrogen gas was purged overnight to remove hydrogen chloride gas generated by the reaction between tungsten hexachloride and nonylphenol, to obtain a polymerization catalyst.

10 ml of this solution, 1.0 ml of acetylacetone and 500 ml of the monomer mixture were mixed to prepare a solution A having a tungsten content of 0.01M.

[Preparation of activator component solution] Trioctylaluminum 85 and dioctylaluminum iodide 15 and siglyme 300 were prepared in a molar ratio of 500 ml, and mixed with 500 ml of a mixed monomer to obtain an aluminum content of 0.03 M.
Solution B was prepared.

The above solution was taken out into a cylinder in which 10 ml of the catalyst component solution (solution A) and 10 ml of the activator component solution (solution B) were heated to a predetermined temperature and then sufficiently replaced with nitrogen.

The liquid was simultaneously extruded from such a syringe at a constant speed and introduced into a nozzle, where it was molded by an ultra-small RIM machine capable of collision mixing and pouring into a mold, whereby a brown tough plate-like product could be formed.

From the molded sample to the notched Izod sample
A TMA sample was cut out and the softening point and impact resistance were measured. TMA measured the softening point in the needle penetration mode in a nitrogen stream and is shown in Table 3.

As can be seen from the results, it can be seen that the low-viscosity solution improves impact resistance and softening point, which are generally contradictory properties. It can be seen that such effects are greater in those having a large amount of unsaturated bonds, that is, polybutadiene, polyisoprene, etc., than the partial water additive, and the unsaturated bond has a large effect.

Examples 11 to 14 Solution A and solution B were obtained in the same manner as in Example 1 except that those shown in Table 4 below were used as the monomer mixture. Each of these
Rapidly stir each 10 ml in a beaker under a nitrogen stream and mix it with 60
It was poured into a mold where a plate-shaped molded product heated to ℃ was obtained, and a large plate-shaped molded product was obtained.

The impact resistance and thermal softening point (by TMA) of such a molding were measured and are summarized in Table 5.

As can be seen from the results, by copolymerizing a cyano group-substituted monomer and a monomer having a polar functional group such as a methoxycarbonyl group, a softening point is lowered and a flexible and tough molded product is obtained, It can be seen that the impact resistance is further improved.

Claims (1)

[Claims] 1. A method for bulk polymerization of a metathesis polymerization monomer in the presence of a metathesis polymerization catalyst system to obtain a crosslinked polymer molding, wherein the polymerization is a non-telechelic liquid rubber having 2 to 40% by weight of an unsaturated bond. The method for producing an impact-resistant crosslinked polymer molded article, wherein the liquid rubber is used in the range of 5 to 20% by weight based on the total amount of the metathesis polymerizable monomer.