JPH03291265A - Alkyl xanthate compound, preparation thereof and use thereof - Google Patents

Abstract

NEW MATERIAL:An alkyl xanthate compound of formula I (R1 is 1-18C alkyl). EXAMPLE:Xylylene bis(ethyl xanthate). USE:Useful as a photopolymerization initiator. The compound of formula I is employed for a polymerization reaction to prepare a polymer slightly having a color and capable of being controlled into various mol. wts. PREPARATION:An aliphatic alcohol of formula II (R2 is 1-18C alkyl) is reacted with an alkali metal hydroxide or alkali metal, with carbon disulfide and subsequently with para xylylene dichloride to provide the compound of formula I. When a polymer is prepared, the prepared crude product of formula I is re-crystallized in benzene/methanol solvent for purification, mixed with a radically polymerizable monomer and irradiated with UV rays.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a novel alkyl xanthate compound and a method for producing the same, and the compound of the present invention is a diene monomer, an acrylic ester monomer, It is useful as a photopolymerization initiator for various radically polymerizable monomers such as polymers. Furthermore, the obtained polymer can be used as a polymeric photopolymerization initiator, and by forming it into a molded product, it can be used in a wide range of fields such as covering hoses, wires, and cables.

[Prior Art] Conventionally, in the photopolymerization of various radically polymerizable monomers using ultraviolet light, disulfide compounds such as tetraalkylthiuram disulfide and tetraalkylxanthogen disulfide, and compounds such as xylylene bis(dialkyl carbamate) have been used. has been used. In polymerization using xylylene bis(dialkyl carbamate) compounds, it is possible to photopolymerize a wide range of monomers such as diene monomers, styrene or styrene derivatives, acrylate monomers such as acrylic acid and acrylic esters. However, disulfide compounds have no activity as photopolymerization initiators and function as chain transfer agents. Therefore, it is usually used in combination with a radical polymerization initiator. Regarding photopolymerization, for example, Mr. Otsu (Journal of Macromolecules Science, (J, M
acroaol, Sci.

Chew, ), Volume A21, Issues 8 & 9, Page 961, 1
984). However, as mentioned above, disulfide photopolymerization initiators have low polymerization initiation ability and low photodegradability, making it difficult to carry out quantitative polymerization reactions, and it is difficult to control the molecular weight when used in combination with radical polymerization initiators. It has its drawbacks. Furthermore, carbamate-based photopolymerization initiators have the disadvantage that the resulting polymer is colored from deep yellow to brown. Furthermore, when the above-mentioned carbamate-based initiator is used, the initiator may not be completely consumed during polymerization depending on the monomer, resulting in a fatal drawback that molecular weight control is difficult. This tendency is noticeable when producing low molecular weight polymers that require the use of a large amount of initiator, and it has been difficult to control the molecular weight over a wide range from low molecular weight to high molecular weight. Furthermore, there have been no reports of success in controlling the molecular weight of diene monomers using conventional carbamate compounds.

[Problem to be Solved by the Invention] As mentioned above, carbamate compounds conventionally used for photopolymerization have the problems that it is difficult to control the molecular weight over a wide range and the polymer is colored. was. The present invention attempts to solve the above two problems at the same time.

[Means for Solving the Problems] In order to solve the above problems, as a result of intensive studies on the polymerization activity of various compounds, we found that the yield is lower than that of the following general formula [1] Bamate initiator. The present inventors have discovered that even when the monomer/initiator charging ratio (molar ratio) is 50 or less, no unreacted initiator remains and the molecular weight can be controlled.

The present invention will be explained in detail below.

As the xanthate compound of the present invention, the following general formula [
I] (Here, R1 represents an alkyl group having 1 to 18 carbon atoms) A variety of compounds can be used, and specific examples of these compounds include: (Here, R1 represents an alkyl group having 1 to 18 carbon atoms) (represents an alkyl group from 1 to 18) is used as a photopolymerization initiator to polymerize diene monomers, acrylic acid ester monomers, etc. , there is no problem of coloring of the polymer, and Cal-S can be mentioned.

The method for producing the above compound that can be used in the present invention is the following reaction formula [I] CnH2n+1-OB''
0KCnHzn++ -OK + C3t-CnH2n
It can be easily produced using the method represented by +1-QC-8K1.

Alcohols that can be used in the production of the xanthate compounds of the present invention include methanol, ethanol,
Examples include n-propatool, inpropatool, n-butanol, t-butanol, 5ec-butanol, n-pentanol, n-hexanol, but alcohols having 7 or more carbon atoms can be used similarly. .

In addition, alkaline compounds include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide,
Alkali metals such as sodium, lithium or potassium can be used.

Although p-xylylene dichloride is preferably used after recrystallization, alcohols and carbon disulfide do not need to be particularly purified and can be used in production without any problems.

Although it is preferable to use alcohol, which is a starting material for the xanthate compound, as the reaction solvent, it is also possible to use a non-halogen aromatic hydrocarbon solvent.

Although the reaction temperature is not particularly limited, it is preferably carried out at 0 to 50°C, and more preferably 0 to 30°C.

A method for producing a xandate compound using the above raw materials will be briefly described below.

A solution in which a predetermined amount of alcohol is dissolved in an aliphatic hydrocarbon or an aromatic hydrocarbon, or a predetermined amount of alkali metal hydroxide such as potassium hydroxide, or metallic potassium etc. An alkali metal is added and the reaction is allowed to proceed until the alkali metal or hydroxide of the alkali metal is completely dissolved. Thereafter, a predetermined amount of carbon disulfide is slowly added and reacted for about 30 minutes, and then a predetermined amount of paraxylylene dichloride is added and reacted for about 3 hours. After the reaction, the reaction solution is concentrated to dryness, then dissolved in a non-halogenated solvent such as tetrahydrofuran or benzene, filtered to remove insoluble matter, washed with water, and concentrated to obtain a crude product.

In producing the polymer, it is preferable to use a purified product obtained by recrystallizing the obtained crude product with a benzene/methanol solvent. Therefore, when the product is liquid, it is preferable to use a product separated and purified by column chromatography or the like since distillation is difficult.

Examples of radically polymerizable monomers that can be polymerized with the xanthate compound of the present invention include diene monomers such as chloroprene, 2゜3-dichlorobutadiene, butadiene, isoprene, and 1-chlorobutadiene, methyl acrylate,
Ethyl acrylate, n-propyl acrylate, 1s
o-propyl acrylate, cyclohexyl acrylate, β-hydroxy acrylate, β-hydroxypropyl acrylate, glycidyl acrylate, benzyl acrylate, phenoxyethyl acrylate, 2-hydroxy 3-phenoxypropyl acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, dicyclo pentenyloxyethyl acrylate,
Acrylic acid ester monomers such as n-butyl acrylate, 5ec-butyl acrylate, t-butyl acrylate, methyl methacrylate, cyanoethyl acrylate, and cyanobutyl acrylate; vinyl such as vinyl acetate, vinyl ethyl ether, vinylidene chloride, and vinyl chloride; Examples include acrylic acid monomers such as acrylic acid and methacrylic acid.

This does not limit the present invention in any way; it is possible to polymerize a wide variety of monomers, and theoretically it is applicable to all radically polymerizable monomers.

Furthermore, it is also possible to synthesize a random copolymer in which two or more of the monomers exemplified above or other radically polymerizable monomers are combined.

The polymerization method will be described below. During polymerization, it is preferable to use a photopolymerization device, and as a light source, either a low-pressure mercury lamp or a high-pressure mercury lamp can be suitably used, although the wavelength distribution is different.

A polymerization solvent is not particularly required in the production of low molecular weight polymers and bulk polymerization can be carried out, but it is necessary that the initiator be dissolved in the monomer.

When using a polymerization solvent, it is preferable to use one with a small chain transfer constant, such as benzene, toluene, or xylene.

When using a polymerization solvent, the monomer concentration is preferably 30% by weight or less. Polymerization temperature is not particularly limited, but 0
-90 degreeC is preferable, and 0-50 degreeC is used suitably.

The degree of polymerization can be easily adjusted by changing the initiator/monomer charging ratio, and a polymer with a desired molecular weight can be obtained. Although the polymerization time needs to be appropriately determined depending on the monomer to be polymerized, it is usually carried out for 10 to 30 hours.

[Effects of the Invention] According to the present invention, a novel compound that can be used as a photopolymerization initiator and a polymerization method using the compound can be provided. Furthermore, the polymer obtained by the polymerization reaction has almost no coloration, and when this compound is used, it is possible to control the molecular weight of various polymers over a wide range, which has been difficult in the past.

[Example] Hereinafter, the present invention will be explained in detail with reference to Examples, but these are not intended to limit the present invention in any way.

The alkyl xanthate compounds of the present invention and the produced polymers were analyzed using the following measuring instruments and measuring conditions.

(1) GPC Tosoh Corporation TSK CP-8000 column: G4000) 1x, G2000HXL detector: L
IV-11000 Solvent: THF Flow rate: 1. Oml/sin.

Pressure: 62 kg/ci 2 Temperature: 25°C (2)' H-NMR Varian EX-180NM+? Spectrometer solvent: deuterated chloroform, internal standard: TMS In addition, in the following examples, the photopolymerization reaction was performed using a UM452 (450W) high-pressure mercury lamp manufactured by Ushio Inc., and a lighting device fUM-453B-A. This was done using

Example 1 Synthesis of xylylene bis(ethylxanthate) 11.4 g of potassium hydroxide was added to 100 ml of ethanol 3
An ethanol solution of potassium hydroxide was prepared by dissolving the mixture under stirring for 0 minutes. 13.1 g of carbon disulfide was added to this solution and reacted for 2 hours with stirring. After the reaction was completed, the reaction solution was concentrated using an evaporator, poured into a large amount of ether, the precipitate was filtered, and the filtered product was recrystallized from ethanol to obtain potassium ethyl xanthate. Next, 15 g of the obtained xanthate was dissolved again in ethanol, and 6.8 g of xylylene dichloride was added. The reaction was carried out for 4 hours with stirring, and the reaction solution was passed through the mouth to remove potassium chloride, a reaction by-product.The solvent was removed, and the passed through the solution was dissolved in benzene, and the solution was passed through the mouth again. The resulting sip was recrystallized from a benzene/alcohol mixed solvent to obtain 12 g of white crystals. The obtained compound is estimated to be p-xylylene bis(ethylxanthate) having the following structure from the measurement results of 1H-NMR (the analysis results are shown below).

Analysis value 'H-NMR (80MHz, CDCl5) 61.
30 (trlplet, 68.-0-CH, CI) 64
．． 27 (singlet, 4H, -C, H4-CH, -
8C(S)-)64.630(QLIartet, 4H
1-0-C,! ij, CHx) 67.111 (slng
let, 4H, aromatic H, -C, lj, -
CH, -) Example 2 Synthesis of xylylene bis(n-butylxanthate) 100 ml of butanol and 3.95 g of sodium metal were reacted for 1 hour with stirring to prepare an alcoholade solution. Add 13.1g of carbon disulfide to this solution and mix with stirring.
Allowed time to react. After the reaction was completed, the reaction solution was concentrated using an evaporator, poured into a large amount of ether, the precipitate was filtered, and the filtered product was recrystallized from ethanol to obtain potassium ethyl xanthate. Next, the obtained xanthate 15
Redissolve g in ethanol and add xylylene dichloride 7
．． 6g was added. The reaction was carried out for 4 hours with stirring, and the reaction solution was passed through the mouth to remove potassium chloride, a reaction by-product.The solvent was removed, and the passed through the solution was dissolved in benzene, and the solution was passed through the mouth again.

The resulting sip was recrystallized from a benzene/alcohol mixed solvent to obtain 15 g of white crystals. The obtained compound is '
From the H-NMR measurement results (the analysis results are shown below), it is estimated to be p-xylylene bis(butylxanthate) having the following structure.

' HN M R (80MHz, CDCl5) 60.8
0-1.0 (8H1-0-CHt(CL)i CH,)
61.0-2.0(broad, 8H, -0-C)It
(C%)tcHs) δ4.27 (Singlet, 4
H, -C6H, -CHl-9-C(S)-)64.53
(quartet, 4H, -0-CH, (CH,),
CH, ) 67.18 (singlet, 4H, aros
atic Hs, -C,H, -CHt-) Example 3 Synthesis of xylylene bis(methylxanthate) 100ml of methanol and 3.95g of metallic sodium were heated for 1 hour.
The reaction was carried out under stirring to prepare an alcoholade solution. 13.11 g of carbon disulfide was added to this solution and reacted for 2 hours with stirring. After the reaction was completed, the reaction solution was concentrated using an evaporator, poured into a large amount of ether, the precipitate was filtered through the mouth, and the filtered product was recrystallized with ethanol to obtain potassium methyl xanthate. Next, 16 g of the obtained xanthate was redissolved in methanol, and 8 g of xylylene dichloride analysis value 1G was added. The reaction was carried out for 4 hours with stirring, and the reaction solution was passed through the mouth to remove potassium chloride, a reaction by-product, and then the solvent was removed, and the passed through solution was dissolved in benzene and passed through the mouth again. The resulting sip was recrystallized from a benzene/alcohol mixed solvent to obtain 35 g of single yellow crystals. The obtained compound is p-xylylene bis(n
-methylxanthate).

Analysis value 'H-NMR (BOMHz, CDCl,) 64.
15 (singlet, 4H, -C,H, -CH-3-
C(S)-)64.33(slnglet,8H,-0
-CB) δ7.22 (slnglet, 4H, aroma
atic H8,-C,Hl-CH,-) Example 4 Synthesis of xylylene bis(n-propylxanthate) 100 ml of propatool and 3.95 g of sodium metal were reacted for 1 hour with stirring to prepare an Alcolade solution. 13.11 g of carbon disulfide was added to this solution and reacted for 2 hours with stirring. After the reaction was completed, the reaction solution was concentrated using an evaporator, poured into a large amount of ether, the precipitate was filtered, and the filtered product was recrystallized with ethanol to obtain potassium moopropyl xanthate. Next, 15 g of the obtained xanthate was dissolved again in propatool, and 9.30 g of xylylene dichloride was added. The reaction was carried out for 4 hours with stirring, and the reaction solution was passed through the mouth to remove potassium chloride, a reaction by-product, and then the solvent was removed, and the passed through solution was dissolved in benzene and passed through the mouth again. The resulting sip was recrystallized from a benzene/alcohol mixed solvent to obtain 33.8 g of white crystals. The obtained compound is p-xylylene bis(n
-propyl xanthate).

Analysis value lH-NMR (BOMHz, CDCl,) 60.9
5C1r191et, 6H, -0-CH, CH, CH,
)61.3-2.1(broad, IIH2-0-CJ
CH, CHs) δ4-30 (s I n g 1 e
t, 4 H, -Ca H4-0% -S -C(S
) -) 64.50 (trlplet, 4H, -0-
Cfi, CI, CH,) 67.25 (slnglet,
4H, aromatic Hs, -C,)! ,-Cut
-) Example 5 Example 3 in a 100ml Pyrex glass ampoule
p-xylylene bis(methylxanthate) synthesized by
0.7196g, benzene 50.0m! After charging 9.971 g of chloroprene and thoroughly degassing, the ampoule was melt-sealed. A high-temperature water tank was maintained at 30° C., the ampoule was fixed at a distance of 80 mm from a high-pressure mercury lamp, and ultraviolet rays were irradiated for 17 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer. The obtained polymer was a pale yellow viscous liquid (yield 60%). As a result of analyzing this polymer by terminal quantitative method using 'H-NMR, the number average molecular weight (Mn)
was 2.740, and had a molecular weight close to the theoretical value (2,560) calculated from the charge and monomer addition rate, and a polymer with almost no coloring was obtained.

Example 6 Example 1 in a 100 m1 Pyrex glass ampoule
p-xylylene bis(ethylxanthate) synthesized by
0.3412 g, benzene 50.0 ml, and ethyl acrylate 10.0 g were charged, and after sufficient deaeration, the ampoule was melt-sealed. A thermostatic water bath was maintained at 20° C., the ampoule was fixed at a distance of 70 mm from a high-pressure mercury lamp, and ultraviolet rays were irradiated for 22 hours without stirring. After polymerization, the ampoule was opened and the contents poured into a large amount of hexane to isolate the polymer. The obtained polymer was a pale yellow viscous liquid (yield 72%). As a result of analyzing this polymer by GPC, the number average molecular weight (M n ) was 7.400, which was close to the theoretical value (7,210), and there was almost no coloration.

Example 7 Example 3 in a 100 m1 Pyrex glass ampoule
p-xylylene bis(methylxanthate) synthesized by
0.4987g, benzene 50. After 10.0 g of butyl acrylate and sufficient deaeration, the ampoule was melt-sealed. A thermostatic water bath was maintained at 20° C., the ampoule was fixed at a distance of 70 mm from a high-pressure mercury lamp, and ultraviolet rays were irradiated for 17 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer. The obtained polymer was a pale yellow viscous liquid (yield 60%). As a result of analyzing this polymer by GPC, the number average molecular weight (M n ) was 3,680, which was close to the theoretical value (3,830), and there was almost no coloration.

Example 8 Example 2 in a 100ml Pyrex glass ampoule
After charging 0.9094 g of p-xylylene bis(n-butyl xanthate) synthesized in step 1, 50 Oml of benzene, and 10.067 g of Rio Robreno, and thoroughly degassing,
The ampoule was sealed. A high-temperature water tank was maintained at 30° C., the ampoule was fixed at a distance of 80 mm from a high-pressure mercury lamp, and ultraviolet rays were irradiated for 17 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer. The obtained polymer was a pale yellow viscous liquid (yield 79%). This polymer is 'H-N
As a result of analysis by terminal quantitative method using MR, the number average molecular weight (Mn) was 2.730, which was close to the theoretical value (3,100) calculated from the preparation, and there was almost no coloration.

Example 9 Example 3 in a 500 m1 Pyrex glass ampoule
p-xylylene bis(methylxanthate) synthesized by
1.3039 g of benzene, 350 ml of benzene, and 100 g of riooblen were charged, and after sufficient deaeration, the ampoule was melt-sealed. A high-temperature water bath was maintained at 15° C., the ampoule was fixed at a distance of 100 mm from a high-pressure mercury lamp, and ultraviolet rays were irradiated for 20 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer. The obtained polymer was a pale yellow viscous liquid (yield 40%). As a result of analyzing this polymer by GPC,
The number average molecular weight (Mn) was 11,000, which was close to the theoretical value (13,500) calculated from the preparation, and there was almost no coloration.

Example 10 Example 1 in a 10100 Pyrex glass ampoule
Xylylene bis(ethyl xanthate) synthesized in 0.
7g2J1g, benzene 50. Oml.

After 9.997 g of chloroprene was charged and sufficiently degassed, the ampoule was melt-sealed. Keep the high temperature water tank at 30℃,
The above ampoule was fixed at a distance of 80 mm from a high-pressure mercury lamp, and was irradiated with ultraviolet rays for 17 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer. The obtained polymer was a pale yellow viscous liquid (yield 67%). This polymer is 'H-N
As a result of analysis by terminal quantitative method using MR, the number average molecular weight (M n ) was 3,370, which is close to the theoretical value (2,970) calculated from the preparation, and the polymer was not colored. There were hardly any.

Example 11 Example 4 in a 100ml Pyrex glass ampoule
0.8463 g of p-xylylene bis(n-propyl xanthate) synthesized in step 1, 50.0 ml of benzene, and 10.1657 g of chlorobrene were charged, and after sufficient deaeration, the ampoule was sealed by melting. Keep the high temperature water tank at 30℃,
The above ampoule was fixed at a distance of 80 mm from a high-pressure mercury lamp, and was irradiated with ultraviolet rays for 17 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer. The obtained polymer was a pale yellow viscous liquid (yield 79%). This polymer was converted into 1H-NM
As a result of analysis by the terminal quantitative method using R, the number average molecular weight (Mn) was 3,460, which was close to the theoretical value (3,100) calculated from the preparation, and there was almost no coloration.

Example 12 Example 4 in a 100ml Pyrex glass ampoule
0.1871 g of p-xylylene bis(n-propyl xanthate) synthesized in step 1, 50.0 ml of benzene, and 10.0 g of ethyl acrylate were charged, and after sufficient deaeration, the ampoule was sealed by melting. A thermostatic water bath was maintained at 20° C., the ampoule was fixed at a distance of 70 mm from a high-pressure mercury lamp, and ultraviolet rays were irradiated for 17 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer. The obtained polymer was a pale yellow viscous liquid (yield 80%). GPC this polymer
As a result of analysis, the number average molecular weight (Mn) was 15,800.
It had a molecular weight close to the theoretical value (16,020) and was hardly colored.

Comparative Example 1 0.9036 g of xylylene bis(diethyldithiocarbamate) in a 100 ml Pyrex glass ampoule
, benzene 50.0ml, Rio.

After preparing 9.663g of Blend and thoroughly deaerating it,
The ampoule was sealed. A high-temperature water tank was maintained at 30° C., the ampoule was fixed at a distance of 80 mm from a high-pressure mercury lamp, and ultraviolet rays were irradiated for 17 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer. The obtained polymer was a viscous liquid (
yield 59%). As a result of analyzing this polymer by GPC, the number average molecular weight (M n ) was 13,300, which was more than 5 times the theoretical value (2,210) calculated from the preparation. Further, the obtained polymer was significantly colored brown, and about 40% of the polymerization initiator remained.

Comparative Example 2 0.2089 g of xylylene bis(diethyldithiocarbamate) in a 100 m1 Pyrex glass ampoule
, benzene 50.0ml1. , ricy.

Bren 10. After charging Og and sufficiently degassing, the ampoule was melt-sealed. A thermostatic water bath was maintained at 15° C., the ampoule was fixed at a distance of 80 mm from a high-pressure mercury lamp, and ultraviolet rays were irradiated for 22 hours without stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of methanol to isolate the polymer.

The obtained polymer was a viscous liquid (yield 54%)
. As a result of analyzing this polymer by GPC, the number average molecular weight (M
n) is 2,460, which is the theoretical value calculated from the preparation (
10,500), and it was difficult to control the molecular weight. Furthermore, the obtained polymer was colored dark brown.

Comparative Example 3 0.2224 g of xylylene bis(diethyldithiocarbamate) in a 100 ml Pyrex glass ampoule
, benzene 50.0ml, ethyl acrylate 13.8ml
After 6 g was charged and sufficiently degassed, the ampoule was melt-sealed. Keep the constant temperature water tank at 15℃ and 80m from the high pressure mercury lamp.
The above ampoule was fixed at a distance of m and irradiated with purple p# rays for 20 hours while stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of hexane to isolate the polymer (yield 97%). As a result of analyzing this polymer by GPC, the number average molecular weight (Mn) was 16,700, which was significantly different from the theoretical value (24,100) calculated from the preparation, making it difficult to control the molecular weight. there were. Furthermore, the obtained polymer was colored pale yellow.

Comparative Example 4 0.2156 g of xylylene bis(diethyldithiocarbamate) in a 100 m1 Pyrex glass ampoule
, benzene 50.0 ml, butyl acrylate 13.4
After fully deaerating the ampoule, the ampoule was melt-sealed. Keep a constant temperature water tank at 15℃, 80mm from a high pressure mercury lamp.
Fix the above ampoule at a distance of 20 hours under stirring.
Irradiated with ultraviolet light. After polymerization, the ampoule was opened and the contents were poured into a large amount of hexane to isolate the polymer.

The obtained polymer was a viscous liquid (yield 89%)
DAs a result of analyzing this polymer by GPC, the number average molecular weight (
M n ) was 29,900, which was a molecular weight significantly different from the theoretical value (22,200) calculated from the preparation, making it difficult to control the molecular weight. Furthermore, the obtained polymer was colored pale yellow.

Comparative Example 5 0.642 g of xylylene bis(diethyldithiocarbamate) was placed in a 100 ml glass ampoule made by Baylex.
Benzene 50.0ml, methyl methacrylate 16.0ml
After 3 g was charged and sufficiently degassed, the ampoule was melt-sealed. Keep a constant temperature water tank at 15℃ and gQm from a high pressure mercury lamp.
The above ampoule was fixed at a distance of m and irradiated with ultraviolet rays for 20 hours while stirring. After polymerization, the ampoule was opened and the contents were poured into a large amount of hexane to isolate the polymer. The obtained polymer was a viscous liquid (yield: 84%). As a result of analyzing this polymer by GPC, the number average molecular weight (Mn
) is 16.300, which is the theoretical value calculated from the preparation (
21,060), and it was difficult to control the molecular weight.

Claims (4)

[Claims] (1) Alkyl xanthate compounds represented by the following general formula [I] ▲Mathematical formulas, chemical formulas, tables, etc.▼[I] (Here, R_1 represents an alkyl group having 1 to 18 carbon atoms.) . (2) Adding an alkali metal hydroxide or an alkali metal to an aliphatic alcohol represented by the following general formula [II] R_2OH[II] (where R_2 represents an alkyl group having 1 to 18 carbon atoms) A method for producing a compound according to claim (1), which comprises reacting carbon disulfide and then reacting paraxylylene dichloride after the reaction. (3) Alkyl xanthate compounds represented by the following general formula [I] ▲Mathematical formulas, chemical formulas, tables, etc.▼[I] (Here, R_1 represents an alkyl group having 1 to 18 carbon atoms.) A photopolymerization initiator consisting of. (4) Alkyl xanthate compounds represented by the following general formula [I] ▲Mathematical formulas, chemical formulas, tables, etc.▼[I] (Here, R_1 represents an alkyl group having 1 to 18 carbon atoms.) , and a radically polymerizable monomer is polymerized by irradiating it with ultraviolet rays.