JPH0116249B2 - - Google Patents

Description

[Detailed description of the invention] The present invention is based on the formula:

This invention relates to a method for ring-opening polymerization of a bicyclo compound having a bicyclo ring represented by the formula in its molecule. It has been known that various types of bicyclo compounds can be used as stabilizers for vinyl chloride resins, herbicides, and the like. Further, when these bicyclo compounds are subjected to ring-opening polymerization by a known method, catalysts such as BF ₃ ·OEt ₂ , PF ₅ , CF ₃ SO ₃ H, etc. are generally used. Although these catalysts are certainly effective for ring-opening polymerization of bicyclo compounds, they may not be usable depending on the use of the bicyclo compound. For example, the present inventors have attempted to use bicyclo compounds as dental materials. However, conventionally known catalysts could not be used in the oral cavity and could not be used as dental materials. Therefore, an object of the present invention is to develop a ring-opening polymerization catalyst for bicyclo compounds that can be used satisfactorily even in the oral cavity. In order to achieve the above object, the present inventors have been conducting intensive research and development of catalysts. As a result, the inventors discovered that heteropolyacids are excellent catalysts for the ring-opening polymerization reaction of bicyclo compounds, and completed the present invention. The present invention

This is a method for ring-opening polymerization of a bicyclo compound, which comprises ring-opening polymerizing a bicyclo compound having a bicyclo ring represented by the formula in its molecule using a heteropolyacid as a catalyst. The bicyclo compounds that are the object of the present invention are bicyclo rings, that is,

There are no particular limitations as long as the compound has [Formula] in its molecule. In general, the formula The most typical example is a bicyclo compound represented by the formula (wherein R ₁ and R ₂ represent the same or different hydrogens or monovalent organic groups). The above-mentioned monovalent organic group is not particularly limited, and any group may be used. Specific examples of generally suitably used monovalent organic groups include CH ₃ −, C ₂ H ₅ −, n-C ₃ H ₇ −, iso-
C ₃ H ₇ −, n−C ₄ H ₉ −, iso−C ₅ H ₁₁ −, C ₁₀ H ₂₁ −
Saturated hydrocarbon residues such as; _H2C =CH- group, _CH3-
CH=CH- group,

[Formula] Unsaturated hydrocarbon residue having groups, etc.; NH ₂ −, CH ₃ NH−,

Organic groups containing amino groups such as [Formula]; CH ₃ CONH−, CH ₃ NHCONH−,

Organic group containing an amide group such as [Formula]; CH ₃ NHCOOCH ₂ −, CH ₃ CH ₂ NHCOOCH ₂
-Organic group containing urethane group such as _CH2 =CHCOO
−, CH ₂ =C(CH ₃ )COO−, CH ₂ =
CHCOOCH ₂ −, CH ₂ =C(CH ₃ )COOCH ₂ −,
_CH2 =C( _CH3 ) _COO ( _CH2CH2O )m-,

Acrylic acid represented by the formula (where m is an integer from 1 to 500), etc.
Residues such as methacrylic acid; organic groups in which some or all of the hydrogen atoms are substituted with halogen atoms, hydroxyl, etc.; The most important feature of the present invention lies in the catalyst used in ring-opening polymerization of the bicyclo compound. That is, the catalyst used in the present invention is a heteropolyacid. The heteropolyacid is not particularly limited, and known ones can be used. As mentioned above, the heteropolyacid is a general term that includes heteropolyacid salts, and in the present invention, not only heteropolyacids but also their salts can be used as long as they are acidic salts. Various types of heteropolyacids are known, but in general, for example, Kyoritsu Shuppan Co., Ltd.,
24th edition published on September 15th, "Chemistry Encyclopedia 8"
Those described on pages 339 to 340 are preferably used. In particular, silicotungstic acid, silicomolybdic acid, phosphotungstic acid, phosphomolybdic acid, acid salts thereof, and the like are preferably used. In general, heteropolyacids are compounds containing a large amount of water of crystallization. It is considered that these waters of crystallization play an extremely important role in the ring-opening reaction of the bicyclo compound. For example, the presence of the water of crystallization is considered to be helpful in increasing the degree of dissociation of the heteropolyacid. Therefore, when determining the amount of heteropolyacid added, it is generally preferable to select it so that it is in the range of 0.01 to 20 wt% based on the bicyclo compound, but the total amount of water including crystal water is 0.01 to 20 wt% based on the bicyclo compound.
It is preferable to add and mix water in a range of 20 wt%. The method for ring-opening polymerization of a bicyclo compound in the present invention is not particularly limited, and any known method may be employed. Generally, if the bicyclo compound is in liquid form,
If it is in solid form, it may be dissolved in a suitable solvent such as methyl methacrylate or methyl acrylate, and then the heteropolyacid may be added and mixed. Since the heteropolyacid is generally a solid substance, when it is dissolved in the above-mentioned solvent, it may be mixed as is, but it is usually preferable to dissolve it in advance in a solvent such as water, acetone, alcohol, etc. before use. The ring-opening polymerization reaction of the bicyclo compound may be carried out in any manner, but generally a method in which it is carried out in a mold or by casting between plates is often suitably employed. The conditions for the ring-opening polymerization reaction of the bicyclo compound are not particularly limited and may be appropriately selected from known conditions, but are usually 0°C to 200°C, preferably 30°C to 130°C for several minutes to several hours. All you have to do is react. Since the present invention performs ring-opening polymerization of a bicyclo compound using a heteropolyacid catalyst, it can be used satisfactorily even in the oral cavity. To this end, the present invention provides a new use of bicyclo compounds as dental materials, and in this sense, the contribution of the present invention is immeasurable. In carrying out the present invention, the polymer obtained in the present invention may be mixed with fillers, adhesives, etc. conventionally known in the dental industry, and in the reaction of the present invention, the polymers obtained in the present invention may be mixed with fillers, adhesives, etc. that are known to be used in dentistry. A mixture of polymerizable monomers can be used. Examples of particularly suitable polymerizable monomers for mixing include methyl methacrylate, methyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, ethylene glycol methacrylate, di- or tri- or tetra-ethylene glycol diacrylate, and bisphenol A diacrylate. ,2,2′−
Bis(methacryloxyethoxyphenyl)propane, 2,2'-bis(γ-methacryloxy-β
-hydroxypropoxyphenyl)propane,
N,N-dimethylaminoethyl methacrylate,
These include glycidyl methacrylate, styrene, and vinyl acetate. It is also effective to add polymeric compounds such as polymethacrylate, polyethyl methacrylate, polystyrene, unsaturated polyester resin, and epoxy acrylate resin to adjust the viscosity and curing speed during the reaction. EXAMPLES In order to explain the present invention more specifically, the present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. Examples 1 to 9, Comparative Examples 1 to 3 3 g of 1,4-diethyl-2,6,7-trioxabicyclo[2,2,2]octane was introduced into a 5 ml sealed ampoule. To this was added a solution of 0.09 g of heteropolyacid shown in Table 1 below dissolved in 0.2 ml of acetone, and immediately frozen in dry ice. Thereafter, the tube was degassed for about 1 minute and sealed. The reaction was carried out at a predetermined temperature for 20 hours after dissolving the mixture in the ampoule. The ring opening rate of bicyclo ring, which is a guideline for catalytic ability, is determined by the ¹ H-NMR spectrum of 1,4-diethyl-2,6,7-trioxabicyclo[2,2,2]octane before reaction and the mixture after reaction. Calculated from. If the absorption intensities based on the six methylene protons of the bicyclo ring before and after the reaction are a and a', and the absorption intensities based on other protons are b and b', then the ring opening rate x
(%) can be expressed by the following formula. x (%)=ab'-a'b/a(a'+b')×100 The results obtained from the above measurements are shown in Table 1 below. Also, for comparison, 1,4-diethyl-2,6,
7-Trioxabicyclo[2,2,2]octane was mixed with _BF3 · _OEt2 , which is known as a bicyclo ring-opening catalyst.
The same measurements as above were carried out when 3 mol % was added, and the results are also listed in Table 1 below.

[Table] Examples 10 to 12, Comparative Example 4 1,4-diethyl-2, used in Examples 1 to 9
6,7-trioxabicyclo[2,2,2]octane to 1-ethyl-4-methacryloxymethyl-
2,6,7-trioxabicyclo[2,2,2]
Table 2 below shows the results of the same measurements as in Examples 1 to 9 except for using octane. Also, for comparison, 1
-ethyl-4-methacryloxymethyl-2,6,
7-Trioxabicyclo[2,2,2]octane was mixed with _BF3 · _OEt2 , which is known as a bicyclo ring-opening catalyst.
The same measurements as above were carried out when 3 mol % was added, and the results are also listed in Table 2 below.

【table】

【table】

Claims (1)

[Scope of Claims] 1. A method for ring-opening polymerization of a bicyclo compound, which comprises ring-opening polymerizing a bicyclo compound having a bicyclo ring represented by the formula [Formula] in its molecule using a heteropolyacid as a catalyst. 2 Heteropolyacid is 0.01 to bicyclo compound
The ring-opening polymerization process according to claim 1, wherein ~20% by weight is used.