JPH0431429A - Production method of norbornene polymer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to norbornene-based polymers produced by bulk polymerization of norbornene-based monomers, and more particularly relates to norbornene-based polymers having high heat distortion temperature, improved flexural modulus and good impact resistance. The present invention relates to a method for producing norbornene-based polymers having excellent properties and moldability.

[Prior art] Dicyclopentadiene (DCP), methyltetracyclododecene (MTD),
Norbornene-based monomers are produced by bulk polymerizing tricyclic or tetracyclic norbornene-based monomers such as ethylidene tetracyclododecene alone or in appropriate combinations in a mold in the presence of a metasense catalyst system (methasense catalyst and co-catalyst). Obtaining polymers is a well-known technique (Japanese Patent Application Laid-open No. 1983
-129013, JP-A-59-51911, JP-A-61-179214, JP-A-61-293208, etc.).

In order to improve the heat distortion temperature or glass transition temperature (Tg) of these norbornene-based polymers,
It is also known to use tricyclopentadiene (TCP) in combination (JP-A-63-227623, JP-A-6
4-9219 etc.). However, when TCPs are used in combination, the heat distortion temperature is improved, but the impact resistance is reduced.

In addition, the reaction stock solution consisting of a norbornene monomer mixture containing TCPs and a metasense catalyst system shows a rapid increase in viscosity after the start of polymerization, and then the polymerization is completed after a considerable period of time. Flow marks (flow pattern traces) and weld lines formed by the coalescence of unevenly cured parts (polymer) occur,
These cause surface defects and deterioration of physical properties of molded products.

On the other hand, 5-
RIM using alkenyl-2-norbornenes (VNBs) as the main raw material and RIM using a mixture of DCP and VNBs are known (JP-A-63-12612, JP-A-63-97610, etc.). ). Also, VNB and DCP
Natural rubber, polyisoprene (IR
), RIM in the presence of styrene-butadiene copolymer (SBR) is also known (JP-A-63-97611).
.

However, VNBs are bicyclic monomers, and the heat deformation temperature of the obtained polymer is low, making them impractical.In fact, VNB homopolymers are rubber-like polymers, which can be used as rigid polymers. In order to achieve this, it is necessary to further apply heat to harden the resin after the reaction in the mold is completed (Japanese Patent Application Laid-Open No. 63-97610). Further, when VNB is used in combination with DCP resin, the rigidity is improved, but as above, it is not an industrially advantageous method because it requires further heating and curing after the reaction in the mold is completed.

Moreover, the Izod impact value in this case is at most 20
kg-cm/cm, which is not sufficient.

By the way, the present inventors have found that it is effective to further use VNBs in combination as a means to improve the moldability, which is a drawback of using bicyclic or tetracyclic norbornene monomers in combination with TCPs. , filed a patent application first (
(Patent Application No. 1-285555). In this case, a problem arises in that the Tg decreases when the proportion of VNBs used in the mixture increases, and when the proportion of TCPs used is increased as a countermeasure to this problem, there is a problem that the impact resistance decreases.

[Problem to be solved by the invention]

The object of the present invention is to have excellent moldability such as adjustable pot life and good appearance, as well as good flexural modulus, high heat distortion temperature, and impact resistance. The purpose of the present invention is to provide norbornene-based polymers.

In order to compensate for the drawbacks of systems in combination with bicyclic or tetracyclic norbornene monomers such as DCP, TCPs, and VNBs, the present inventors developed polybutadiene (B R), a general-purpose elastomer, and styrene-based monomers. When butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), etc. were added and bulk polymerization was performed using RIM, the impact resistance of the molded product was significantly improved. It was found that it decreased.

Therefore, as a result of further research, we added a specific elastomer that is difficult to miscible with these monomers to a monomer mixture of bicyclic and tetracyclic norbornene monomers, TCPs, and VNBs in specific proportions, and created RIM. By carrying out bulk polymerization, they discovered that it was possible to obtain a norbornene-based polymer with high impact resistance, high flexural modulus, heat resistance, and improved moldability, and a good appearance. Based on this, the present invention has been completed.

[Means to solve the problem]

Thus, according to the present invention, (a) 10 to 50% by weight of bicyclic and/or tetracyclic norbornene monomers, (
b) 10 to 50% by weight of tricyclopentadines, and (c) 40 to 8% of 5-alkenyl-2-norbornenes.
A monomer mixture containing 0% by weight in the coexistence of a hydrocarbon elastomer with a solubility parameter of 8.2 or less,
A method for producing norbornene-based polymers is provided, which is characterized by carrying out bulk polymerization using a metasense catalyst system.

Further, according to the present invention, a reaction stock solution for producing such a norbornene-based polymer is provided.

The present invention will be explained in detail below.

(Tri- to Tetracyclic Norbornene Monomer) In the present invention, a bicyclic or tetracyclic norbornene monomer is used in order to obtain a polymer with good heat distortion temperature, impact resistance, and flexural modulus.

Examples of the bicyclic norbornene monomer include dicyclopentadiene, dihydrodicyclopentadiene, cyclopentadiene-methylcyclopentadiene codimer,
1.4-methano-1゜4.4a, 5,6,7,8,8a
-Octahydronaphthalene, etc. can be mentioned.

Tetracyclic norbornene monomers include tetracyclododecene, methyltetracyclododecene, ethyltetracyclododecene, dimethyltetracyclododecene, ethylidenetetracyclododecene, vinyltetracyclododecene, phenyltetracyclododecene, etc. can be mentioned.

In addition, if desired, halogen, ester group, ether group,
Tetracyclododecene having a polar group such as a cyano group, an imido group, or a pyridyl group as a substituent can also be used.

Among them, dicyclopentadiene (DCP) is preferred from the viewpoint of easy availability.

These norbornene monomers may be used alone or in combination of two or more.

(TCPs) Tricyclopentadiene (TCP) is prepared by heating dicyclopentadiene at 120 to 250'C under an inert gas atmosphere.
It can be obtained by heat treatment for 0.5 to 20 hours. Heat treatment of DCPs yields a monomer mixture containing TCPs and unreacted dicyclopentadiene.

In the present invention, from such a mixture, TCP
Although these compounds may be used after isolation, the mixture may also be used as is without isolation.

(VNBs) The 5-alkenyl-2-norbornenes used in the present invention have a lower alkenyl group having a terminal double bond at the 5-position, and the alkenyl group has 2 to 6 carbon atoms, particularly 2
-3 is preferred, and may further have a lower alkyl group or alkenyl group at the 6th and/or 5th positions.

Furthermore, it may be 2.5-norbornadiene, which may have a methyl group or a halogen atom at another site.

Specific examples of these stronger 5-alkenyl-2-norbornenes include, for example, 5-vinylbicif[2,2,
1] hept-2-ene (VNB), 5-impropenylbicyclo[2,2,1]hept-2-ene (IPN),
5-vinyl-5-methylbicyclo[2,2,11hept-2-ene 55-vinyl-4-methylbicyclo[2,2
,1]hept-2-ene, 5-vinyl-4-vinylbicyclo[2,2,11hept-2-ene, 5-propenyl-bicyclo[2,2,1]hept-2-ene, 5-butenyl -bicyclo[2,2,1,1hept-2-ene, 5
-Pentenyl-bicyclo[2°2.1]hept-2-ene, monomethyl substituted products thereof, monochloro substituted products thereof, dichloro substituted products thereof, 5-a-chlorovinylbicyclo[2,2,1]hept -2-ene etc. can be mentioned. Also included is 5-vinylbicyclo[2,2,1]hept-1,4-diene, which is a Diels-Alder reaction product of cyclopentadiene and vinyl acetylene.

Among these, VNB and IPN are preferred because of their ease of acquisition. These can be obtained as Diels-Alder reaction products of butadiene or isoprene with cyclopentadiene. In addition, when high-purity dicyclopentadiene is produced as a monomer for open J1 polymerization by distillation from the C5 fraction, which is a by-product of ethylene production by naphza cracking, VNB and IPN are produced as by-products. It can be obtained cheaply.

(a) Tri- to tetracyclic norbornene monomer, (b) TC
The usage ratio of P and (elVNBs) is (a) 10-5
0% by weight, fb) 10-50% by weight, (c) 40-80
% by weight, preferably 45-70% by weight. If the proportion of VNBs is too small, the effect of improving moldability such as pot life adjustment will be small (and the effect of improving impact strength will be small. Conversely, if it is too large, the Tg of the produced polymer will decrease too much) Therefore, both are unfavorable.

(Other Monomers) In addition to the above three types of monomers, monomers capable of ring-opening polymerization can be used in combination without impairing the object of the present invention.

Specifically, 2-norbornene, 5-methyl-2-norbornene, 5-ethyl-2-norbornene, 5-butyl-2-norbornene, 5-hexyl-2, which can undergo ring-opening polymerization.
- norbornene, 5-ethylidene-2-norbornene,
Bicyclic norbornene monomers such as 5-phenylnorbornene, or cyclobutene, cyclopentene,
Examples include monocyclic cycloolefins such as cyclopentadiene, cyclooctene, and cyclododecene.

(Elastomer) A polymer obtained by bulk polymerization using the monomer mixture according to the present invention has excellent moldability, heat resistance, and high elastic modulus, but has a problem of low impact strength.

By the way, various elastomers are generally used for the purpose of improving impact strength.

As an elastomer for this purpose, a hydrocarbon-based elastomer that does not inhibit polymerization by a metasense catalyst system and is soluble in norbornene-based monomers is usually used.

Among these, elastomers having good compatibility with norbornene monomers, such as SBR, butadiene-styrene block copolymer (SEBS), SBS, and SIS, are widely used.

Contrary to expectations, it was found that a polymer obtained by adding such an elastomer to a monomer mixture containing VNBs and performing bulk polymerization had very low impact strength. Therefore, in order to increase impact strength, we conducted extensive studies and found that elastomers with low compatibility with norbornene monomers can increase impact strength.

That is, the elastomer used in the present invention is a hydrocarbon elastomer having a solubility parameter (SP value) of 8.2 or less. When elastomers that are susceptible to sagging are shown along with their SP values, for example, natural rubber (8,0), ethylene propylene rubber (EPT or EPDM; 7.9), butyl rubber (IIR; 7.8), polyisoprone (IR; 8.0
), etc.

The amount of such elastomer used is 1oo of the monomer mixture.
It is usually 1 to 10 parts by weight, preferably 2 to 6 parts by weight, per 1 part of 3H. If the amount of elastomer used is too small, the impact strength improvement effect will be low, and if it is too large, the flexural modulus will decrease.

These elastomers may be used alone or in combination of two or more. The above-mentioned hydrocarbon-based elastomer such as SBH can be used together with the elastomer of the present invention, as long as the effects of the present invention are not impaired.

(Metasense Catalyst System) The catalyst used in the present invention is a metasense catalyst known as a catalyst for ring-opening polymerization of norbornene monomers. Therefore, molybdenum-based metasense catalysts such as molybdenum halides, oxyhalides, oxides, organic ammonium salts, etc. are preferable, and in particular, JP-A-58-12
Organic ammonium salts described in JP-A-59-51911 and the like are preferred.

Specific examples of molybdenum-based metasense catalysts include tridodecylammonium molybdate, methyltricabrylammonium molybdate, tri(tridecyl)ammonium molybdate, trioctylammonium soribdate, molybdenum pentachloride, molybdenum oxytrichloride, and the like.

Specific examples of the cocatalyst (activator) include alkylaluminum halides, alkoxyalkylaluminum halides, aryloxyalkylaluminum halides, and organic tin compounds.

In the case of alkylaluminum halides, there is a problem that polymerization starts immediately when a solution containing a catalyst is mixed. can delay the start of
129013, 61-120814).

In addition to catalysts and activators, halogenated hydrocarbons such as chloroform, carbon tetrachloride, and hexachlorocyclobentajenna (for example, JP-A-60-79035) and halogens such as silicon tetrachloride, germanium tetrachloride, and lead tetrachloride are also used. Chemical compound (Japanese Patent Application Laid-open No. 186730/1986) may be used in combination.

The metasense catalyst is usually about 0 per mole of 1,000 mol.
．． It is used in a range of 0.01 to 50 mmol, preferably 0.91 to 20 mmol. The cocatalyst (activator) is usually 0.1 to 200 (molar ratio) to the catalyst component, preferably (
is used in a range of 1 to 1° (molar ratio).

Both the metasense catalyst and the cocatalyst are preferably used after being dissolved in a monomer, but they may also be used after being suspended or dissolved in a small amount of a solvent as long as the properties of the product are not essentially impaired.

(Norbornene Polymer) In the present invention, the RIM method is used in which a norbornene monomer is subjected to ring-opening polymerization in bulk using a metasense catalyst in a mold. As long as the polymerization is substantially bulk polymerization, a small amount of inert solvent may be present.

In a preferred method for producing bulk ring-opening polymers, the norbornene-based monomer mixture is divided into two parts, placed in separate containers, the metasense catalyst is added to one part, and the co-catalyst is added to the other part, and two stable reaction stock solutions are prepared. Prepare. These two reaction stock solutions are mixed and then poured into a mold of a predetermined shape, where ring-opening polymerization is carried out in bulk. The mold may be a simple formwork.

In the present invention, an impingement mixer, conventionally known as a RIM device, can be used to mix the two reaction stock solutions. In this case, the vessels containing the two reaction stock solutions become sources of separate streams. RI two types of flow
The mixture is instantaneously mixed using the mixing head of the M machine, and then injected into a hot mold, where it is immediately subjected to bulk polymerization to obtain a molded product.

Furthermore, after the mixing of two types of reaction stock solutions is completed in a mixer, injection or injection may be performed several times into a preheated mold (for example, Japanese Patent Application Laid-open No. 59-51911, U.S. Pat. 4.426.502) or may be injected continuously. This method has the advantage that it can be made smaller and can be operated at lower pressure than an impingement mixing device, and it also has the advantage of increasing the injection speed when the amount of reinforcing material such as glass uA fiber is large. By slowing down, it becomes possible to uniformly impregnate the reaction stock solution into the system.

Furthermore, the present invention is not limited to the method of using two types of reaction stock solutions. As can be easily understood by those skilled in the art,
For example, various modifications are possible, such as placing monomers and desired additives in a third container and using it as a third stream.

The material of the mold used in the present invention is not particularly limited to metal, and any material such as synthetic resin, wood, or cement can be used, but from an economic standpoint, resin molds, plated surfaces, electroformed molds, etc. are preferred. used.

The mold temperature is usually room temperature or higher, preferably 40 to 200 ℃
℃, more preferably 50 to 120℃. The mold clamping pressure is usually within the range of 0.1 to 100 kg/cryf.

The polymerization time may be selected appropriately, but the time from the pot life in the mold to the smoking time is usually 5.
within minutes, preferably within 2 minutes.

Note that pot life (PL) is the time it takes for the reaction stock solution containing the metasense catalyst and cocatalyst to increase in viscosity and become difficult to flow after mixing the reaction stock solution containing the metasense catalyst and cocatalyst (the time it takes for the reaction stock solution to become difficult to flow from a liquid state to a pudding state). Smoking time (SMT) refers to the reaction progressing further, rapid heat generation occurs, and at the same time a slight white smoke is observed from the surface of the produced polymer, after which the polymerization reaction quickly ends. This refers to the time from the mixing of the reaction stock solution to the generation of white smoke.

Therefore, the longer the PL and the smaller the SMT/PL value, the better the moldability. In short, the longer the PL, the better the operability, and the shorter the time from the start of the reaction in the mold to the end of polymerization, the shorter the molding production time.

The reaction stock solution is usually stored and operated under an atmosphere of an inert gas such as nitrogen gas, but the mold is not necessarily sealed with an inert gas.

(Optional ingredients) Antioxidants, fillers, pigments, colorants, foaming agents, flame retardants,
By blending various additives such as a sliding agent, a dicyclopentadiene thermopolymerized resin, and its hydrogenated product, the properties of the resulting polymer can be modified.

As antioxidants, there are various antioxidants for Plusdec and rubber, such as phenol-based, phosphorus-based, and amine-based antioxidants.

Fillers include milled glass, carbon black, talc,
There are inorganic fillers such as calcium carbonate and mica.

Additives are usually mixed in one or both of the reaction solutions in advance.

[Examples] The present invention will be described in more detail with reference to Examples and Comparative Examples below, but the present invention is not limited only to these Examples. In addition, parts and percentages in these examples are based on critical condition unless otherwise specified.

[Example 1, Comparative Example 1] 2.6-di-t-butyl-4-hydroxytoluene (B
99.3% pure dicyclopentadiene (DCP) containing 11000 ppp of HT), 96.1% pure tricyclopentadiene (TCP), and 99.8% pure
A mixture of 5-vinylbicyclo[2,2,11hept-2-ene (VNB) of Three parts of Kogyo ■ trade name, Mitsui EPT brand 4045) were dissolved.

This mixture was divided into two equal parts, one containing DEAC at 41 mmol/12, and n-propyl alcohol at 50 mmol/I2. , silicon tetrachloride was added at a concentration of 20 mmol/β, and the mixture was thoroughly mixed to obtain a solution A.

On the other hand, BHTJ moiety and tri(dodecyl)ammonium molybdate were added at a concentration of 12 mmol/β,
(Mixed to make liquid B.

100 mff of both reaction stock solutions A and B were taken and mixed at 30°C to measure the reaction activity, and the results are shown in Table 1.

Both reaction solutions A and B were mixed at a ratio of 1:1 using a gear pump and a power mixer, and a 500 mm x 500 mm x
The mixture was poured into a mold heated to 60° C. with a spatial volume of 3 mm at approximately normal pressure. Injection time was approximately 30 seconds.

After the injection was completed, the reaction was carried out for 90 seconds. Thereafter, the molded product (norbornene polymer) was taken out from the mold, and the appearance and physical properties of the molded product were measured, and the results are shown in Table 1.

(Leaving space below) As is clear from Table 1, the reaction stock solution containing the 1,000-mold mixture of the present invention has a long PI (and good operability) and a small SMT/PL value (and inside the mold). The polymerization reaction proceeds immediately at
Both the flexural modulus and the Izot impact strength show high values.

On the other hand, Comparative Example 1 in which the three component monomers are not used together
(Experiment numbers 1-4 to 1-9) had poor moldability or the physical properties of the molded product were not satisfactory.

In other words, in experiment number 1-4 using only DCP, the flexural modulus and impact strength were relatively good, but SMT/P
Large L value (poor moldability).

In experiment number 1-5 using only TCP, the reaction could not be evaluated because the monomer was solid at room temperature. In experiments number 1-6 using only VNB, the SMT/PL value was small (
Although moldability is good, the molded product obtained is rubber-like and cannot be used.

In Experiment No. 1-7 in which DCP and TCP were used together, the Tg was good, but the SMT/PL value was large and the moldability was poor. In experiment number 1-8 using DCP and VNB together, S
The M T / PI value is small and the formability is good, but the Tg
It has a low flexural modulus and is not practical. TCP and VNB
In combined experiment number 1-9, the SMT/PL value was small and the moldability was good, but the impact strength was reduced.

[Example 2, Comparative Example 2] Molding was carried out in the same manner as in Example 1-1, except that the elastomer in Table 2 was used, and the physical properties of the obtained molded product were measured. and the result in the second
Shown in the table.

As is clear from Table 2, when an elastomer with a low SP value such as EPDM or IIR is used (Example 2),
Although the Izot impact strength is markedly improved, when general-purpose impact modifiers such as SBS, SIS, BR, etc. are used (Comparative Example 2), no improvement in the Izot impact strength is observed.

(The following is a blank space) [Effects of the Invention] Thus, according to the present invention, it is possible to provide a norbornene-based polymer having high heat deformation temperature and flexural modulus, as well as good impact resistance and good moldability.

Claims (2)

[Claims] (1) (a) 10 to 50% by weight of tricyclic and/or tetracyclic norbornene monomers, (b) 10 to 50% by weight of tricyclopentadienes, and (c) 40% by weight of 5-alkenyl-2-norbornenes. A method for producing a norbornene polymer, which comprises bulk polymerizing a monomer mixture containing up to 80% by weight using a metasense catalyst system in the coexistence of a hydrocarbon elastomer having a solubility parameter of 8.2 or less. (2) (a) 10 to 50% by weight of tricyclic and/or tetracyclic norbornene monomers, (b) 10 to 50% by weight of tricyclopentadienes, and (c) 40% by weight of 5-alkenyl-2-norbornenes. A reaction stock solution containing a monomer mixture containing ~80% by weight, a hydrocarbon elastomer with a solubility parameter of 8.2 or less, and a metasense catalyst, and the monomer mixture, the hydrocarbon elastomer, and a cocatalyst. A reaction stock solution for producing norbornene-based polymers, consisting of a reaction stock solution and a reaction stock solution.