JPS6099150A - Resin composition containing rare earth element and its manufacture - Google Patents

Abstract

PURPOSE:To obtain the titled composition of good optical properties with high shielding performance from thermal neutron beam, by uniformly dispersing and dissolving at least one compound containing rare earth element selected from gadolinium, samarium and europium in a resin consisting of transparent thermoplastic and/or thermosetting one except methacrylic resin. CONSTITUTION:The objective composition can be obtained by uniformly dispersing and dissolving (A) at least one compound containing rare earth element selected from gadolinium, samarium and europium in (B) a resin consisting of transparent thermoplastic and/or thermosetting one except methacrylic resin. The manufacturing process is as follows: a blend made up of (1) said resin, i.e. the component (B) containing >=50wt% of aromatic vinyl polymer, (2) said rare earth element compound(s), (3) a solvent dissolvable for said compound(s), of formula R1COOH (R1 is 1-20C hydrocarbon residue) or R2OCO-R3-COOH (R2 is H or 1-9C hydrocarbon residue, R3 is 1-6C hydrocarbon residue) and (4) polymerization initiator is polymerized in a mold. The weight concentration of said element in the whole resin content should be 0.001-10wt%.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a resin composition containing a Hakode element system consisting of gadolinium, samarium and/or europium, and more particularly, a resin composition containing a Hakode element system consisting of gadolinium, samarium and/or europium. The present invention relates to a resin composition containing a surface element and having various physical properties such as selective absorption and biluminescence of radiation and electromagnetic waves, and a method for producing the same.

[Prior art] Transparent resin materials such as styrene resin are mainly used in the form of plate crystals as a substitute for inorganic glass, and are used in various ways due to their ease of molding and processability, as well as their impact resistance. used in the field. However, since these synthetic resins do not have radiation shielding ability, they cannot be used for that purpose. Therefore, in recent years, radiation shielding materials containing lead in methacrylic resin or styrene resin have been developed (4
'f Publication No. 35-2360, Japanese Unexamined Patent Publication No. 53-9994
No. 53-9995, No. 53-9996, No. 53-63310, etc.).

However, the above-mentioned lead-containing radiation shielding material is suitable for electromagnetic waves such as X-rays, gamma rays, and alpha rays.

Although it effectively shields charged particles such as β-rays,
It is insufficient for thermal neutron beams.

On the other hand, it is also known to add a boron compound to polyethylene or methacrylic resin as a polymer material with neutral expected shielding (Japanese Patent Laid-Open No. 144597/1983). However, although this method also has a large neutron beam absorption capacity, the helium and lithium produced in the neutron absorption reaction have almost no neutron absorption capacity, so their capacity tends to decrease as the amount of neutron absorption increases. However, the optical and mechanical properties have not yet reached a satisfactory level.

In addition to the boron compounds mentioned above, samarium, europium, and gadolinium, which are rare earth elements with atomic numbers 62, 63, and 64, are known to have a greater ability to absorb thermal neutrons than boron as substances that absorb neutrons. There is. However, since samarium, europium, and gadolinium are metallic solids, they have poor compatibility with synthetic resins, and no transparent synthetic resins have yet been produced except for methacrylic resins, which have excellent optical and mechanical properties.

[Purpose of the invention]

In view of this situation, an object of the present invention is to provide a transparent resin composition which solves the above problems and is excellent in shielding thermal neutron beams, and furthermore, provides a transparent resin composition which not only shields thermal neutron beams but also has a transparent resin composition which is excellent in shielding thermal neutron beams. The object of the present invention is to provide a transparent resin composition with good optical properties.

[Achievement of invention]

The composition of the present invention is transparent and includes a resin made of a thermoplastic resin and/or a thermosetting resin excluding a methacrylic resin, in which a predominant element compound consisting of at least one of gadolinium, samarium, or europium is uniformly fractionated. The present invention relates to a transparent resin composition containing a seat element which is obtained by dissolving it. Here, methacrylic resin refers to methyl methacrylate polymer resin or methyl methacrylate as the main component. 50 MjAi5
: 1 or more) means a copolymer resin that is different from this and other copolymerizable monomers.

[Embodiments of the invention]

In the present invention, thermoplastic resins other than methacrylic resins include, for example, styrene polymers, styrene as a main component, and monomers copolymerizable with styrene such as methyl methacrylate, α-methylstyrene, maleic anhydride, etc. Examples include copolymer resins, cellulose-based 4"F BW and natural product resins such as cellulose ester and gelatin, and water-soluble resins such as polyvinyl alcohol and polyvinylpyrrolidone. Transparent thermosetting resins include allyl diglycol carbonate resin. , unsaturated polyester, etc.

Further, a method for producing a resin composition containing a boxed base system using a resin containing an aromatic vinyl compound as a main component as a transparent resin includes, for example, a monomer component such as (,) an aromatic vinyl compound and/or a partial polymer thereof. (b) the above-mentioned primary element compound, (c) the following general formula showing solubility for the above-mentioned components (a) and (b), R1-C- 01 ((1) (wherein, R1 is a saturated or unsaturated hydrocarbon residue having 1 to 20 carbon atoms): (wherein, R2 is hydrogen or a hydrocarbon residue having 1 to 9 carbon atoms, R3 is a saturated or unsaturated hydrocarbon residue having 1 to 6 carbon atoms): (In the formula, R4 is hydrogen or a methyl group, and A is a saturated or unsaturated hydrocarbon residue having 1 to 6 carbon atoms.)
6 alkylene group, n is O or an integer from 1 to 10): (wherein, R5 is hydrogen or a methyl group, R6 has 2 to 10 carbon atoms)
6): R, -OH(5) (In the formula, R7 is a saturated or unsaturated hydrocarbon residue having 3 to 10 carbon atoms): R8+A2-0+rnH(6) (In the formula, R8 is OH or a saturated or unsaturated hydrocarbon residue having 1 to 10 carbon atoms, A2 is an alkylene group having 2 to 4 carbon atoms, and m is an integer of 1 to 10.) At least one solvent selected from and (d) a method characterized by placing a mixture including a polymerization initiator in a mold.

In the above production method, examples of the aromatic vinyl compound as component (a) include styrene and α-methylstyrene. One or more types of these may be used. (a)
Partial polymers of these monomers can also be used as components.

Furthermore, if desired, monomers copolymerizable with the aromatic vinyl compound can be used in an amount of less than 50% by weight, based on the total monomer mixture. Examples of such copolymerizable monomers include acrylic acetate, methacrylic ester, maleic anhydride, and ethylene glycol dimethacrylate.

Further, the above partial polymer is not particularly limited as long as it does not impede the purpose of the present invention, but generally has a molecular weight of 1 to 5,000.
It has a viscosity of 0 to 50 cps and contains a quantity of polymer.

The Hakode element-based compounds used in the present invention are oxides, hydroxides, and inorganic acids or hot acids of boronate (for example, oxides of borosilicate elements and inorganic acids or hot acids) Gadolinium nitrate, samarium acrylate, gadolinium methacrylate, propionic europium, caprylic gadolinium, caprylic gadolinium, gadolinium caprate, gadolinium isobutyrate 11, gadolinium laurate, 2-ethinotohexane 〃Thrinium), their double salts or their double salts with other metal salts, and tris(acetylacetonato)gadolinium, penzoyltrichloroacetyl
Examples include complexes such as lua heptatonate and gatlinium.

The amount of these elemental compounds used on the fabric is in the range of 0.001 to 10% based on the total resin content as the weight concentration of the boxed element atoms. If it is less than 0.0O1911, the performance based on the elements on the fabric, such as the thermal neutron beam absorption of the resulting resin composition, decreases,
On the other hand, if it exceeds 10%, mechanical properties and transparency will be impaired.

Further, the general formula (1) used in the present invention.

(2)? (3) , (4) # (5) and (
The solvent shown in 6) is a co-solvent for uniformly dissolving the elemental compound on the fabric in the resin raw material. Saturated fatty acids; unsaturated alcohols such as 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate; saturated aliphatic alcohols such as propioalcohol and cyclohexylalmol; and glycols such as ethylene glycol, diethylene glycol and propylene glycol.

Among these solvents, methacrylic acid, acrylic acid, 2-
Preferred are monomers copolymerizable with styrene or styrene derivatives, such as hydroxyethyl methacrylate and 2-hydroxyethyl acrylate. These solvents can be used alone or in combination of two or more.

The amount of solvent to be used in the present invention cannot be roughly determined depending on the type and amount of the Hakde base compound used, but
．． It ranges from 1 to 40% by weight. Usage amount is 0.1% by weight
If it is less than 40% by weight, the fabric elemental compound cannot be dissolved well in the resin raw material, while if it exceeds 40% by weight, the mechanical and thermal properties of the resulting resin plate will deteriorate, which is not preferable.

Examples of the polymerization initiator used in the present invention include peroxides such as benzoyl gas oxide and lauroyl peroxide, 2,2'-azobisisobutyronitrile, 2,2'-azobis-(2,4 --, 'methylvaleronitrile), 2,2'-azobis-(2,4-dimethyl-4-methoxy-valeronitrile), and other known radical initiators such as azobis-based initiators can be used. These polymerization initiators can be used not only alone but also in combination of two or more,
The amount used is 0.001 parts by weight per 100 parts by weight of resin raw material.
~0.1 part by weight.

The template polymerization of the polymerization mixture in the present invention involves the component (a
) l (b) t A mixture consisting of (c) and (d), for example, td inorganic Nt plate, stainless steel! The polymer is injected into a mold made of a metal plate, nickel chromium plate, aluminum plate, etc. and a soft vinyl chloride gasket and allowed to polymerize. Polymerization temperature in template polymerization is 45-95
℃, and the polymerization time is 0.3 to 15 hours.

In the present invention, if necessary, an ultraviolet absorber, an infrared absorber, a photoselective absorber exhibiting absorption in the visible light region, and an X-ray and γ-ray absorber such as lead, bismuth, and thallium may be used in combination.

The cloth-based element-containing transparent resin composition of the present invention is particularly useful as a neutron shielding material, but can also be used in other applications such as optical lenses, filters, light conversion materials, etc.

Example 1 Gadolinium nitrate 3? 17 g of 2-hydroxyethyl methacrylate and 2 f of propylene glycol! Styrene 78FF is added to this solution and stirred to mix. This liquid mixture was a transparent liquid.

Next, add 0.1% of the polymerization catalyst to this mixed solution. 2,2'-
After adding and dissolving azobis-(2,4-dimethylnonoreronitrile) and 0.005 g of dioctyl sulfosuccinate sodium salt as a mold release agent, it was degassed and the plate thickness was set in advance to be 3 mrn. The polymerization was poured into a conventional inorganic glass mold, and the mold was immersed in warm water at 65°C for 4 hours, and then kept in an air bath at 110°C for 120 minutes to complete polymerization. The resin plate taken out from the mold was transparent.

Example 2 1.51 gadolinium nitrate was dissolved in 8.5 y of 2-hydroxyethyl methacrylate, and this was added to 90 fP of styrene and mixed with stirring. This mixture was clear. The same type and amount of polymerization catalyst and mold release agent as used in Example 1 were added to this mixed solution, and cast polymerization was carried out under the same conditions as in Example 1. The obtained resin plate was transparent.

Example 3 Tris(acetylacetonato)gadolinium 1.5g-
is dissolved in methacrylic acid 8.51, and this solution is added to styrene 909- and stirred to mix.

The same polymerization catalyst and mold release agent as in Example 1 were added to this mixed solution, and the same cast polymerization as in Example 1 was performed.

After completion of polymerization, the resin plate peeled off from the mold was transparent.

Example 4 Gadolinium methacrylate 8? and n-octylic acid 2f
/, 7'robilene glycol 151-12-hydroxyethyl methacrylate IP, methyl methacrylate 5? and styrene 83? were mixed and cast polymerization was repeated under the same polymerization conditions as in Example 1. The obtained resin plate was transparent.

Example 5 Gadolinium acrylate 3? , samarium methacrylate 3F, europium methacrylate IP, n-octylic acid 3g-, propylene glycol IP to styrene 891i
', and cast polymerization was repeated under the same polymerization conditions as in Example 1. The obtained resin plate was transparent.

Example 6 Gadolinium methacrylate 4g, lead methacrylate 41
%, n-octylic acid 3g, propylene glycol 2g
-12-hydroxy and ethyl methacrylate) 1%
The mixture was mixed with 86 g of styrene and cast polymerization was repeated under the same conditions as in Example 1. The obtained resin plate was transparent.

Example 7 Partial polymer of styrene and methyl methacrylate (styrene/methyl methacrylate = 674 polymerization 8%) 100
α, α′-Azobis-(2,
4. Dimethylvaleronitrile) 0.044 parts by weight Dioctylsulfosuccinate sodium salt 0 as a mold release agent
．． 005 parts by weight and 2.0 parts by weight of gadolinium oxide with an average particle size of 2μ were added and mixed, and after degassing, the plate thickness was
The polymer was poured into a mold made of tempered glass and a soft vinyl chloride gasket, soaked in hot water at 70°C for 4 hours, and then placed in an air bath at 130°C for 80 minutes to complete polymerization. A resin plate was obtained.

Example 8 Styrene resin (Dainippon Ink & Chemicals @), product name C
R3500) Average particle size 0.5 μ per 100 parts by weight
2.0 parts by weight of gadolinium hydroxide and an average particle size of 2μ
After adding 1.0 parts by weight of gadolinium carbonate and thoroughly mixing in a tumbler to make the mixture homogeneous, the mixture was extruded using an extruder in a conventional manner to obtain a sheet with a thickness of 3 mm.

The results of total light transmittance (%), haze value (%), bending fracture strength (Kf/σ2), and neutron shielding ability (thermal neutron absorption cross section) of the styrene resin plates obtained in Examples 1 to 8 are shown. Shown in 1.

The total light transmittance and haze value are ASTM-D-1.
003-61, bending fracture strength was measured according to ASTM-D-790. The thermal neutron absorption cross section was calculated using the numerical value described in Experimental Chemistry Course (12) Radiochemistry (Maruzen) and the following formula.

However, S: Composition 100y - Thermal neutron absorption cross section of this (
tyn”) Mt ; Atomic weight ω of the i-type element; Abundance S of the i-type element; ; is the thermal neutron absorption cross section (barns) of the seed element Reference example Styrene 70y-, Methyl methacrylate 301.2, z
-azobis-(2,4-dimethylvaleronitrile) o,
After adding and dissolving 0.0051% of osy and dioctyl sulfosuccinate sodium salt, it was degassed and poured into a conventional inorganic glass mold with the plate thickness set in advance to 3 mm. was immersed in warm water at 65°C for 4 hours, and then kept in an air bath at 110°C for 120 minutes to complete polymerization. The resin plate taken out from the mold was transparent.

Claims (1)

[Claims] 1) A transparent elemental compound consisting of at least one of gadolinium, samarium, or europium is uniformly applied to a resin consisting of a thermoplastic resin and/or a thermosetting resin that is transparent in the visible region except for the methacrylic resin MW. A resin composition containing dispersed and dissolved Hakodemoto. 2) The resin composition according to claim 1, wherein the transparent thermoplastic resin contains a polymer of an aromatic vinyl compound in an amount of 50% by weight or more based on the total resin content. 3) The resin composition according to claim 1, wherein the above-mentioned Hakode elemental compound is blended in a weight concentration of atomic atoms in the range of o, ooi to 10% based on the total resin content. 4 Xa) A monomer component such as an aromatic vinyl compound and/or a partial weight thereof of 50% by weight or more based on the total resin content, (b) A boxed elemental compound consisting of at least 1 m of trinium, samarium or haeurobium, (c) Component (a)? The following general formula having solubility in (b), R1-C0OH (1) (in the formula, R1 is a saturated or unsaturated hydrocarbon residue having 1 to 20 carbon atoms): 'R,, -0CO- R3-COOH(2) (wherein R
2 is hydrogen or a saturated or unsaturated hydrocarbon residue having 1 to 9 carbon atoms, R3 is a saturated or unsaturated hydrocarbon residue having 1 to 6 carbon atoms): CH2=C-C-A, -〇 ÷. ■(
3) (In the formula, R4 is hydrogen or a methyl group, %A is a fullkylene group having 2 to 6 carbon atoms, and n is an integer of 0 or 1 to 10): (In the formula, R5 is hydrogen or a methyl group, R6 has carbon number 2~
6): R, -OH(5) (wherein, R7 is a saturated or unsaturated hydrocarbon residue having 3 to 1 carbon atoms): R8(A2-0-)mH(6 ) (wherein R8 is a hydroxyl group or a saturated or unsaturated hydrocarbon residue having 1 to 0 carbon atoms, A2 is an alkylene group having 2 to 4 carbon atoms, and m is an integer from 1 to 1o) A method for producing a transparent resin composition containing a surface element, characterized in that a mixture of at least one solvent and (d) a polymerization initiator is polymerized in a casting pot.