JP5167817B2 - Polythiourethane and poly (trithiocarbonate) polythioether - Google Patents

Description

  The present invention relates to a polymerized cured product such as a novel polythiourethane and poly (trithiocarbonate) polythioether, and a polymerizable composition providing the same. This polymerized cured product is useful as an optical resin because it has excellent optical performance and mechanical performance, and can be used for plastic lenses, prisms, optical fibers, information recording substrates, colored filters, infrared absorption filters, and the like.

  In recent years, plastics, which are lighter than glass, are less likely to break, and are easy to dye, are becoming mainstream optical materials. However, when it is used for spectacle lenses, etc., it is necessary to increase the thickness of the lens with a low refractive index, so that there is a problem that it is difficult to make use of the original features that are lightweight. It was. In addition, plastics generally have a higher refractive index and tend to have a lower Abbe number and a greater chromatic aberration. For these reasons, a resin having a high refractive index and a high Abbe number has been demanded as an optical material. Furthermore, since it is necessary not to be deformed in the operating temperature range when used for a lens or the like, a plastic as an optical application material is also required to have a high glass transition temperature.

  As such an optical resin, a polythiourethane obtained by reacting a polythiol and a polyisocyanate has been proposed (Patent Document 1), and a polythiol having an increased content of sulfur atoms has also been proposed. (Patent Document 2). Since such polythiourethanes generally have a high refractive index of 1.6 or more, many are used as thin and light spectacle lenses.

  However, polythiourethane has a problem that cannot be ignored from the practical aspect that the higher the refractive index, the worse the strength (mechanical performance) against loads such as tension, bending and impact. For example, eyeglass lenses are required to have a high refractive index and a high Abbe number as optical performance, and excellent tensile properties (particularly elongation at break) as mechanical performance. Therefore, a resin that satisfies these requirements is desired. It was.

  Further, as such different types of optical resins, Patent Documents 3 and 4 propose polythioethers obtained by reacting polythiol and polyepithio compounds. Since such polythioethers generally have a refractive index of 1.6 or higher and a glass transition temperature of 80 ° C. or higher, those used as recent thin and light spectacle lenses are increasing.

  However, polythioether has a problem that cannot be ignored from the practical aspect that the higher the refractive index, the worse the strength (mechanical performance) against a load such as tension, bending, and impact. For example, eyeglass lenses are required to have high refractive index and high Abbe number as optical performance, excellent bending characteristics (particularly high bending fracture strain) as mechanical performance, and high glass transition temperature. Therefore, a resin that can satisfy these requirements has been desired.

On the other hand, Patent Document 5 discloses a method for producing poly (trithiocarbonate) by reacting an alkylene sulfide and carbon disulfide in the presence of a catalyst. However, an optical system excellent in optical performance and mechanical performance is disclosed. Nothing was described about the resin for use.
Japanese Patent Publication No. 4-58489 JP-A-5-148340 JP-A-9-71580 Japanese Patent Laid-Open No. 9-110979 Japanese Patent Publication No. 52-36919

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical resin that can be used for spectacle lenses and the like by solving the problems of the prior art as described above. That is, one aspect of the present invention is to provide a polythiourethane having excellent optical performance (refractive index, Abbe number) and mechanical performance (tensile properties; particularly elongation at break) as an optical resin. To do. Further, different embodiments of the present invention have excellent optical performance (high refractive index, high Abbe number), excellent mechanical performance (bending characteristics; particularly bending fracture strain), and high glass transition temperature as optical resins. It is an object of the present invention to provide a polythioether having.

The present invention comprises component (a): poly (trithiocarbonate) polythiol, and
Component (b):
Component (b-1): polyisocyanate and / or polyisothiocyanate, or
Component (b-2): Polyepithio compound
It relates to a polymerized cured product obtained by reacting.
The present invention further comprises component (a): poly (trithiocarbonate) polythiol, and
Component (b):
Component (b-1): polyisocyanate and / or polyisothiocyanate, or
Component (b-2): Polyepithio compound
The present invention relates to a polymerizable composition containing
In addition, the present application discloses the following matters.

1. Component (a): poly (trithiocarbonate) polythiol, and component (b): a polymerized cured product obtained by reacting a compound that reacts with a terminal mercapto group of the poly (trithiocarbonate) polythiol to give a cured product.

  2. The component (a) is represented by the general formula (1):

（式中、Ｒは、二価の炭化水素基を表し、反応に関与しない置換基を有していてもよく、その炭素鎖中にヘテロ原子又は環構造を含有していてもよい。）
で表される繰り返し単位、および末端ＳＨ基を有し、数平均分子量が３００〜２５００であるポリ（トリチオカーボネート）ポリチオールを含有することを特徴とする上記１記載の重合硬化物。

(In the formula, R represents a divalent hydrocarbon group, may have a substituent not involved in the reaction, and may contain a heteroatom or a ring structure in the carbon chain.)
2. The polymerized and cured product according to 1 above, comprising a poly (trithiocarbonate) polythiol having a repeating unit represented by formula (II) and a terminal SH group and a number average molecular weight of 300 to 2500.

  3. 3. The polymerized cured product according to 1 or 2 above, wherein the polythiol compound serving as a thiol component of poly (trithiocarbonate) polythiol is bis (2-mercaptoethyl) sulfide.

  4). The polymerization cured product according to any one of 1 to 3 above, wherein the component (b) is component (b-1): polyisocyanate and / or polyisothiocyanate, and the polymerization cured product is polythiourethane.

  5. The polymerized cured product has the general formula (2):

（式中、Ｒは前記と同様であり、Ｙは、ポリイソシアネート及び／又はポリイソチオシアネートを構成する二価の炭化水素基を表し、反応に関与しない置換基を有していてもよく、その炭素鎖中にヘテロ原子又は環構造を含有していてもよく、Ｘは酸素原子又は硫黄原子を表し、ｎは１以上の整数を表す。）
で表される繰り返し単位を有するポリチオウレタンである上記４記載の重合硬化物。

(In the formula, R is the same as described above, Y represents a divalent hydrocarbon group constituting polyisocyanate and / or polyisothiocyanate, and may have a substituent not involved in the reaction. A carbon atom may contain a hetero atom or a ring structure, X represents an oxygen atom or a sulfur atom, and n represents an integer of 1 or more.)
5. The polymerized cured product according to 4 above, which is a polythiourethane having a repeating unit represented by the formula:

  6). 6. An optical material comprising the polythiourethane as described in 4 or 5 above.

  7). The polymerization cured product according to any one of 1 to 3, wherein the component (b) is a component (b-2): a polyepithio compound, and the polymerization cured product is a poly (trithiocarbonate) polythioether.

  8). 8. An optical material comprising the poly (trithiocarbonate) polythioether described in 7 above.

9. Component (a): a poly (trithiocarbonate) polythiol, and component (b): a polymerizable composition containing a compound that reacts with a terminal mercapto group of the poly (trithiocarbonate) polythiol to give a cured product.

  10. The component (a) is represented by the general formula (1):

（式中、Ｒは、二価の炭化水素基を表し、反応に関与しない置換基を有していてもよく、その炭素鎖中にヘテロ原子又は環構造を含有していてもよい。）
で表される繰り返し単位、および末端ＳＨ基を有し、数平均分子量が３００〜２５００であるポリ（トリチオカーボネート）ポリチオールを含有することを特徴とする上記９記載の重合性組成物。

(In the formula, R represents a divalent hydrocarbon group, may have a substituent not involved in the reaction, and may contain a heteroatom or a ring structure in the carbon chain.)
10. The polymerizable composition as described in 9 above, comprising a poly (trithiocarbonate) polythiol having a repeating unit represented by formula (II) and a terminal SH group and having a number average molecular weight of 300 to 2500.

  11. 11. The polymerizable composition as described in 9 or 10 above, wherein the polythiol compound serving as the thiol component of the poly (trithiocarbonate) polythiol is bis (2-mercaptoethyl) sulfide.

  12 The polymerizable composition according to any one of 9 to 11 above, wherein the component (b) is a component (b-1): polyisocyanate and / or polyisothiocyanate, and gives a polythiourethane as a cured product.

  13. General formula (2):

（式中、Ｒは前記と同様であり、Ｙは、ポリイソシアネート及び／又はポリイソチオシアネートを構成する二価の炭化水素基を表し、反応に関与しない置換基を有していてもよく、その炭素鎖中にヘテロ原子又は環構造を含有していてもよく、Ｘは酸素原子又は硫黄原子を表し、ｎは１以上の整数を表す。）
で表される繰り返し単位を有するポリチオウレタンを与える上記１２記載の重合性組成物。

(In the formula, R is the same as described above, Y represents a divalent hydrocarbon group constituting polyisocyanate and / or polyisothiocyanate, and may have a substituent not involved in the reaction. A carbon atom may contain a hetero atom or a ring structure, X represents an oxygen atom or a sulfur atom, and n represents an integer of 1 or more.)
13. The polymerizable composition as described in 12 above, which gives a polythiourethane having a repeating unit represented by:

  14 The polymerizable composition as described in any one of 9 to 11 above, wherein the component (b) is a component (b-2): a polyepithio compound and gives a poly (trithiocarbonate) polythioether as a polymerized cured product.

  15. 1 to 40% by weight of the component (a), 50 to 99% by weight of the component (b-2), and 0 to 0% of a compound having at least one functional group capable of ring-opening reaction with an epithio group as an optional component. 15. The polymerizable composition as described in 14 above, which is contained in the range of 20% by weight.

  16. An optical material obtained by curing the polymerizable composition as described in any one of 9 to 15 above.

  According to the present invention, polythiourethane that can solve the problems of the prior art, that is, as an optical resin excellent in mechanical performance (tensile properties; particularly elongation at break) in addition to optical performance (refractive index, Abbe number) Thus, it is possible to provide a polythiourethane that can be expected to be used in the future. The polythiourethane of the present invention is expected to be used for optical materials such as thin high-strength plastic lenses, prisms, optical fibers, information recording bases, colored filters, and infrared absorption filters. Furthermore, since the optical resin of the present invention has not only excellent optical performance but also excellent mechanical performance, it is expected to contribute to increasing the strength of various optical materials.

  Furthermore, according to the present invention, a polythioether that can solve the problems of the prior art, that is, an optical performance (refractive index, Abbe number), as well as excellent mechanical performance (bending characteristics; especially bending fracture strain), and a higher glass transition temperature. It is possible to provide a poly (trithiocarbonate) polythioether having a high potential for use as an optical resin. This poly (trithiocarbonate) polythioether is expected to be used for optical materials such as thin high-strength plastic lenses, prisms, optical fibers, information recording bases, colored filters, and infrared absorption filters. Furthermore, since the optical resin of the present invention has not only excellent optical performance but also excellent mechanical performance, it is expected to contribute to increasing the strength of various optical materials.

  The present invention will be described in detail below. As described above, the novel polymerizable composition of the present invention is cured by reacting with component (a): poly (trithiocarbonate) polythiol and component (b): terminal mercapto group of the poly (trithiocarbonate) polythiol. And a compound that gives a product. By selecting the component (b), it becomes a polymerizable composition capable of obtaining a cured product such as polythiourethane or poly (trithiocarbonate) polythioether as a cured product.

  That is, the polythiourethane according to one embodiment of the present invention can be obtained by reacting a poly (trithiocarbonate) polythiol with a polymerizable composition containing polyisocyanate and / or polyisothiocyanate.

  In addition, the polythioether according to a different aspect of the present invention, that is, poly (trithiocarbonate) polythioether can be obtained by reacting a polymerizable composition containing poly (trithiocarbonate) polythiol and a polyepithio compound.

<Component (a): Poly (trithiocarbonate) polythiol>
The poly (trithiocarbonate) polythiol used in the present invention is preferably produced by transesterification of a thiocarbonate compound (thiocarbonate component) and a polythiol compound (thiol component) in the presence of a transesterification catalyst. An example of a typical synthetic reaction scheme is shown as follows.

ここでは、ポリチオール化合物として、Ｒが２価の炭化水素基である場合を示した。２つのＲ^１は、同一でも異なっていてもよく、アルキル基、アリール基等を表す。

Here, the case where R is a divalent hydrocarbon group is shown as the polythiol compound. Two R ^{1 s} may be the same or different and each represents an alkyl group, an aryl group, or the like.

  Examples of the thiocarbonate compound include dialkylthiocarbonates such as dimethylthiocarbonate, diethylthiocarbonate, and dibutylthiocarbonate; diarylthiocarbonates such as diphenylthiocarbonate; alkylene thiocarbonates such as ethylenethiocarbonate and propylenethiocarbonate; Examples thereof include alkylaryl thiocarbonates such as phenylthiocarbonate. Among these thiocarbonate compounds, diarylthiocarbonate is preferable, and diphenylthiocarbonate is particularly preferable.

  As said polythiol compound, the polythiol compound corresponding to the polyol compound used by manufacture of polycarbonate polyol can be used individually or in multiple, Specifically, a polyvalent (at least bivalent) hydrocarbon group (preferably Is a compound having a mercapto group bonded to the free terminal having 2 to 14 carbon atoms. The hydrocarbon group includes an aliphatic (including alicyclic) hydrocarbon group (preferably having 2 to 14 carbon atoms) and an aromatic (including araliphatic) hydrocarbon group (preferably having 6 to 14 carbon atoms). And may have a substituent (alkyl group, alkoxy group, etc.) that does not participate in the reaction, and a heteroatom (oxygen atom, sulfur atom, nitrogen atom) or ring structure (alicyclic ring) in the carbon chain An atom or an atomic group that does not participate in the reaction, such as a structure, an aromatic ring structure, or a heterocyclic structure). In this case, “does not participate in the reaction” means that, in addition to the production of poly (trithiocarbonate) polythiol, it does not participate in the reaction when obtaining a cured product by reaction with the component (b). . That is, when producing a polythiourethane, it means not participating in the reaction, and when producing a polythioether, it means not participating in the reaction.

  Among the polyvalent hydrocarbon groups, those having a valence of 2 or more and an valence of 8 or less, more preferably a valence of 5 or less are preferred, but a divalent one is particularly preferred. Of these, aliphatic ones are preferable, and among them, divalent aliphatic hydrocarbon groups are particularly preferable. That is, in the said polythiol compound, a dithiol compound is preferable and an aliphatic dithiol compound is especially preferable especially. The hetero atom is preferably a sulfur atom or an oxygen atom, and the ring structure is preferably an alicyclic structure or a saturated heterocyclic structure. If the polyvalent hydrocarbon group is a divalent hydrocarbon group, the poly (trithiocarbonate) polythiol is a poly (trithiocarbonate) dithiol having a repeating unit of the general formula (1), and the general formula (1 "R" in the above) corresponds to this divalent hydrocarbon group. In addition, since a hydrocarbon group having a trivalent or higher value increases the branching and / or crosslinking structure in the polymer, it is preferable to select and use it appropriately in consideration of the physical properties of the resulting polythiourethane or polythioether. When a trivalent or higher valent hydrocarbon group is contained, the proportion thereof is preferably within 30%, more preferably within 20% on a molar basis with respect to all polyvalent hydrocarbon groups.

For example, when the divalent hydrocarbon group R ² and the trivalent hydrocarbon group R ³ are contained in the same molecule, the poly (trithiocarbonate) polythiol is branched by the hydrocarbon group R ³ as follows, for example: It has the structure (4).

  Examples of the polythiol compound in which the hydrocarbon group is an aliphatic hydrocarbon group include 1,2-ethanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 1,5-pentanedithiol, 1,6 -Hexanedithiol, 1,7-heptanedithiol, 1,8-octanedithiol, 1,9-nonanedithiol, 1,10-decanedithiol, 1,12-dodecanedithiol, 2,2-dimethyl-1,3-propane Alkanedithiol such as dithiol, 3-methyl-1,5-pentanedithiol, 2-methyl-1,8-octanedithiol, cycloalkanedithiol such as 1,4-cyclohexanedithiol,

  Hetero atoms are contained in carbon chains such as bis (2-mercaptoethyl) ether, bis (2-mercaptoethyl) sulfide, bis (2-mercaptoethyl) disulfide, and 2,2 ′-(ethylenedithio) diethanethiol. Alkanedithiol, alkanedithiol containing an alicyclic structure in the carbon chain such as 1,4-bis (mercaptomethyl) cyclohexane, 2,5-bis (mercaptomethyl) -1,4-dioxane, 2,5- Alkanedithiols containing heteroatoms and alicyclic structures in the carbon chain such as bis (mercaptomethyl) -1,4-dithiane,

  Alkanetrithiols such as 1,1,1-tris (mercaptomethyl) ethane, 2-ethyl-2-mercaptomethyl-1,3-propanedithiol, 1,8-mercapto-4-mercaptomethyl-3,6-thiaoctane And alkanetetrathiol such as tetrakis (mercaptomethyl) methane, 3,3′-thiobis (propane-1,2-dithiol), 2,2′-thiobis (propane-1,3-dithiol), and the like.

  Examples of the polythiol compound in which the hydrocarbon group is an aromatic hydrocarbon group include 1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, toluene-3,4-dithiol, and the like. Aromatic dithiols of 1,2-bis (mercaptomethyl) benzene, 1,3-bis (mercaptomethyl) benzene, 1,4-bis (mercaptomethyl) benzene, and other aliphatic dithiols, Examples include aromatic trithiols such as 5-benzenetrithiol and 1,3,5-tris (mercaptomethyl) benzene.

  Poly (trithiocarbonate) polythiol is transesterified while continuously extracting alcohol (especially aryl alcohol), which is a by-product of thiocarbonate compound (especially diarylthiocarbonate) and polythiol compound, in the presence of a transesterification catalyst. It is preferable to make it react. At this time, the amount of the polythiol compound used is 0.8 to 3.0 times that of the thiocarbonate compound so that all or almost all the terminals of the resulting poly (trithiocarbonate) polythiol molecular chain are mercapto groups. Mole, more preferably 0.85 to 2.5 times mol, and particularly preferably 0.9 to 2.5 times mol. Moreover, it is preferable that the usage-amount of a transesterification catalyst is 1-5000 ppm on a molar basis with respect to a polythiol compound, Furthermore, it is preferable that it is 10-1000 ppm. In order to extract the by-product alcohol, it is preferable to provide a distillation apparatus in the reactor, and the reaction may be performed under a flow of an inert gas (nitrogen, helium, argon, etc.).

  In the transesterification reaction, it is preferable to use diphenylthiocarbonate as the diarylthiocarbonate. In this case, if a polythiol compound having a polyvalent hydrocarbon group is a divalent hydrocarbon group, divalent thiocarbonate is used. The hydrocarbon group R preferably has 4 to 14 carbon atoms. At this time, the amount of the polythiol compound (particularly dithiol compound) in which the carbon number of R is 4 to 14 is 1.05 to 3.0 times mole, more preferably 1.1 to 2.5 times that of diphenylthiocarbonate. It is preferable that all or almost all of the molecular chain terminals are mercapto groups (that is, the proportion of aryloxy groups (particularly phenoxy groups) in the terminal groups is 5% or less, further 2% or less, particularly 1 %) Or less) poly (trithiocarbonate) polythiol. Thus, by controlling the ratio of the aryloxy group in the terminal group, a cured product such as polythiourethane or polythioether excellent in mechanical performance in addition to optical performance can be obtained. The proportion of the aryloxy group is on a molar basis (the same applies hereinafter).

  The conditions (temperature, pressure, time) of the transesterification reaction are not particularly limited as long as the target product can be efficiently produced. For example, a thiocarbonate compound and a polythiol compound are converted into a normal pressure in the presence of a transesterification catalyst. Alternatively, the reaction is performed at 110 to 200 ° C. under reduced pressure for about 1 to 24 hours, and then at 110 to 240 ° C. (especially 140 to 240 ° C.) for about 0.1 to 20 hours under reduced pressure. What is necessary is just to make it react for about 0.1 to 20 hours under the pressure reduction which finally becomes 20 mmHg (2.7 kPa) or less, raising.

  In addition, when a plurality of polythiol compounds are used, a plurality of them may be reacted at the same time, but the corresponding poly (trithiocarbonate) is obtained by transesterifying the thiocarbonate compound and one polythiol compound under the same conditions. A polythiol may be once produced and reacted with another polythiol compound. In the latter case, if the thiocarbonate compound is diphenylthiocarbonate, the polythiol compound (especially dithiol compound) having 4 to 14 carbon atoms in diphenylthiocarbonate and R is transesterified, and then produced poly (trithiocarbonate) It is preferable to react the polythiol with a polythiol compound having 2 to 4 carbon atoms in R (particularly a dithiol compound) to produce the target product.

  The transesterification catalyst is not particularly limited as long as it is a compound that catalyzes the transesterification reaction. For example, potassium carbonate, sodium alkoxide (sodium methoxide, sodium ethoxide, etc.), organic quaternary ammonium salt (tetrabutylammonium hydroxide, etc.) Basic compounds such as tetraalkylammonium hydroxide), titanium compounds such as titanium tetrachloride and tetraalkoxytitanium (tetra-n-butoxy titanium, tetraisopropoxy titanium, etc.), metal tin, tin hydroxide, tin chloride And tin compounds such as dibutyltin dilaurate, dibutyltin oxide, and butyltin tris (2-ethylhexanoate).

Among transesterification catalysts, basic compounds such as potassium carbonate, sodium alkoxide (sodium methoxide, sodium ethoxide, etc.), organic quaternary ammonium salts (tetraalkylammonium hydroxide such as tetrabutylammonium hydroxide), tetra Alkoxy titanium (tetra-n-butoxy titanium, tetraisopropoxy titanium, etc.) is preferable. In the transesterification catalyst, the de-CS ₂ reaction, the coloring degree, and the remaining catalyst amount are within a range in which the optical and mechanical performance of the cured product (polythiourethane or poly (trithiocarbonate) polythioether, etc.) can be maintained at a high level. Any basic compound can be used as long as it can be controlled. Among them, the basic compound can increase the reaction rate and can be generated by the de-CS ₂ reaction at the trithiocarbonate structure (-S-CS-S-) moiety. Thioether structure (if a dithiol compound having a divalent hydrocarbon group R is used, the ratio of -R-S-R-) is the molar basis (the same shall apply hereinafter) and the remaining trithiocarbonate structure and the thioether structure. It is particularly preferable since it is possible to provide a high-quality poly (trithiocarbonate) polythiol that is 3% or less of the total of the above.

Among the basic compounds, an organic quaternary ammonium salt (particularly a tetraalkylammonium hydroxide such as tetrabutylammonium hydroxide) contains a metal component having a thioether structure ratio of 1% or less. More preferred are poly (trithiocarbonate) polythiols that can be obtained. By controlling the de-CS ₂ reaction in this way, the sulfur content and trithiocarbonate structure of poly (trithiocarbonate) polythiol can be maintained at a high level. As a result, the optical and mechanical performance of the cured product (such as polythiourethane or poly (trithiocarbonate) polythioether) can be maintained at a high level. The residual trithiocarbonate structure refers to a trithiocarbonate structure that has not undergone de-CS ₂ reaction.

The number average molecular weight (M _n ) of the poly (trithiocarbonate) polythiol is preferably in the range of 300 to 2500, more preferably 400 to 2000. If this molecular weight is outside the range, the optical and mechanical performance of the cured product will be unsatisfactory. For example, when the number average molecular weight is less than 300, the elongation at break of polythiourethane is low, and when it is greater than 2500, the melting point and crystallization temperature of poly (trithiocarbonate) polythiol are increased, resulting in polyisocyanate and / or polyisocyanate. The compatibility with the isothiocyanate is lowered, and the light transmittance of the polythiourethane is lowered. Similarly, for example, when the number average molecular weight is smaller than 300, the bending fracture strain of the polythioether of the present invention is low, and when it is larger than 2500, the melting point and the crystallization temperature of the poly (trithiocarbonate) polythiol are increased and the polyepithio compound And the light transmittance of the polythioether of the present invention is lowered.

  For this reason, the amount of the thiocarbonate compound and the polythiol compound is adjusted so as to achieve the target molecular weight, but if the number average molecular weight of the reaction product deviates from the target value, for example, if the molecular weight is small, the polythiol compound is further reduced under reduced pressure. It is preferable to adjust the molecular weight by carrying out a transesterification reaction while distilling and adding a polythiol compound and further performing a transesterification reaction when the molecular weight is large.

  After the molecular weight adjustment, the transesterification catalyst remaining in the poly (trithiocarbonate) polythiol is preferably inactivated if necessary. When tetraalkoxytitanium is used, the transesterification catalyst can be deactivated by a known method of adding a phosphorus compound (phosphoric acid, butyl phosphate, dibutyl phosphate, etc.). When used, it can be carried out by adding an equimolar amount of an inorganic acid or an organic acid (sulfuric acid, p-toluenesulfonic acid, etc.) to the catalyst at 40 to 150 ° C. In addition, when an insoluble salt is precipitated by this acid addition, it is preferable to remove it by washing with water.

  The obtained poly (trithiocarbonate) polythiol can reduce the amount of residual catalyst by washing with water. For example, when the catalyst is a basic compound or a titanium compound, the amount of residual catalyst in the poly (trithiocarbonate) polythiol can be reduced to 40 ppm or less, further 10 ppm or less, particularly 2 ppm or less on a weight basis (hereinafter the same). it can. The washing with water can be performed by dissolving poly (trithiocarbonate) polythiol in a good solvent such as methylene chloride, adding an appropriate amount of water, and uniformly mixing or stirring. This operation may be performed a plurality of times as necessary. By controlling the amount of residual catalyst in this way, the optical and mechanical performance of polythiourethane can be maintained at a high level.

  The poly (trithiocarbonate) polythiol thus obtained is preferably poly (trithiocarbonate) dithiol, and more preferably aliphatic. At this time, the dithiol compound used as the thiol component can be used alone or in combination, but if it is used alone, the one using bis (2-mercaptoethyl) sulfide is used in the production of polythiourethane or polythioether at room temperature. Poly (trithiocarbonate) dithiols that can be cast polymerized below can be obtained, which is particularly preferred.

<Component (b-1): Polyisocyanate and / or polyisothiocyanate, and polythiourethane>
The polythiourethane of the present invention is prepared by reacting component (a): poly (trithiocarbonate) polythiol with component (b-1): polyisocyanate and / or polyisothiocyanate (polythio) as follows. By urethanization reaction). At this time, polyisocyanate and polyisothiocyanate may be used alone or in combination.

  As the polyisocyanate, a polyisocyanate usually used in the production of polyurethane can be used. Specifically, a compound in which an isocyanate group is bonded to a free terminal of a polyvalent (at least divalent) hydrocarbon group. Can be mentioned. This hydrocarbon group is an aliphatic (including alicyclic) hydrocarbon group (preferably having 2 to 14 carbon atoms) or an aromatic (including araliphatic) hydrocarbon group (preferably having 6 to 14 carbon atoms). Any of them may have a substituent that does not participate in the reaction (alkyl group, alkoxy group, etc.), and the carbon chain contains a hetero atom (oxygen atom, sulfur atom, nitrogen atom). Also good. If the hydrocarbon group is a divalent hydrocarbon group, “Y” in the general formula (2) corresponds to this hydrocarbon group. As polyisothiocyanate, the polyisothiocyanate corresponding to polyisocyanate can be mentioned, respectively.

  That is, as the aliphatic polyisocyanate, for example, 1,3-trimethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate Alkane polyisocyanates such as 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, 1,9-nonamethylene diisocyanate, 1,10-decamethylene diisocyanate,

  Cycloalkane polyisocyanates such as 1,4-cyclohexane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate, 1,3,5-tris (isocyanomethyl) cyclohexane,

  2,2'-diethyl ether diisocyanate, 2,2'-diethyl sulfide diisocyanate, hexamethylene diisocyanate-biuret, 2-isocyanoethylthio-1,3-isocyanopropane, 1,1-bis (isocyanomethylthio)- Alkane polyisocyanates having heteroatoms such as 4-isocyanobutane, 3,3-bis (isocyanoethylthio) -1-isocyanobutane, 2,3-bis (isocyanoethylthio) -1-isocyanomethylthiopropane, ,

  Isophorone diisocyanate, 1,4-dithian-2,5-diisocyanate, 2,3-bis (isocyanomethyl) -1,4-dithiane, 2,5-bis (isocyanomethyl) -1,4-dithiane, 2 , 5-bis (isocyanoethyl) -1,4-dithiane, cyclopentane-1,3-disulfide-4,5-diisocyanate, 4,5-bis (isocyanomethyl) cyclopentane-1,3-disulfide, 2, -Methyl-4,5-bis (isocyanomethyl) cyclopentane-1,3-disulfide, 2,2-bis (isocyanopropyl) cyclopentane-1,3-disulfide, tetrahydrothiophene-2,5-diisocyanate, 2,5-bis (isocyanomethyl) tetrahydrothiophene, 3,4-bis (isocyanomethyl) tetrahydro Such as cycloalkane polyisocyanates having a heteroatom such as thiophene are exemplified specifically.

  Examples of the aromatic polyisocyanate include p-phenylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), 4,4′-. Diphenylmethane diisocyanate (MDI), 3,3′-methyleneditolylene-4,4′-diisocyanate, tolylene diisocyanate trimethylolpropane adduct, 4,4′-diphenyl ether diisocyanate, tetrachlorophenylene diisocyanate, 3,3′-dichloro- 4,4'-diphenylmethane diisocyanate, triphenylmethane triisocyanate, 1,3,5-tris (isocyanomethyl) benzene, triisocyanate phenylthiophos Eto and the like specifically.

  In the polythiourethanization reaction, a chain extender can be used alone or in combination as a hard segment. Examples of such a chain extender include those usually used in the production of polyurethanes. A low molecular compound having at least two hydrogen atoms that react with an isocyanate group and / or an isothiocyanate group, specifically, a polyol. A compound, a polythiol compound, a polyamine compound, etc. are mentioned.

  Examples of the polyol compound serving as a chain extender include ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 3,3-dimethylol heptane, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,4-bis (hydroxyethyl) cyclohexane, 2-hydroxyethyl ether, 2-hydroxyethyl sulfide, 2,5- Bis (hydroxymethyl) -1,4-dioxane, 2,5-bis ( Dorokishimechiru) -1,4-dithiane, trimethylol ethane, trimethylol propane, and aliphatic polyols such as pentaerythritol,

  Catechol, resorcinol, hydroquinone, 1,3,5-benzenetriol, 1,2-bis (hydroxymethyl) benzene, 1,3-bis (hydroxymethyl) benzene, 1,4-bis (hydroxymethyl) benzene, 1, Aromatic polyols such as 3,5-tris (hydroxymethyl) benzene are exemplified.

  Examples of the polythiol compound serving as a chain extender include 1,2-ethanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 1,5-pentanedithiol, 1,6 -Hexanedithiol, 1,7-heptanedithiol, 1,8-octanedithiol, 1,9-nonanedithiol, 1,10-decanedithiol, 1,12-dodecanedithiol, 2,2-dimethyl-1,3-propane Dithiol, 3-methyl-1,5-pentanedithiol, 2-methyl-1,8-octanedithiol, 1,4-cyclohexanedithiol, 1,4-bis (mercaptomethyl) cyclohexane, bis (2-mercaptoethyl) ether , Bis (2-mercaptoethyl) sulfide, bis (2-mercaptoethyl) Disulfide, 2,5-bis (mercaptomethyl) -1,4-dioxane, 2,5-bis (mercaptomethyl) -1,4-dithiane, 1,1,1-tris (mercaptomethyl) ethane, 2-ethyl -2-mercaptomethyl-1,3-propanedithiol, tetrakis (mercaptomethyl) methane, 3,3′-thiobis (propane-1,2-dithiol), 2,2′-thiobis (propane-1,3-dithiol) ) Aliphatic polythiols such as

  1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, 1,3,5-benzenetrithiol, 1,2-bis (mercaptomethyl) benzene, 1,3-bis (mercaptomethyl) ) Aromatic polythiols such as benzene, 1,4-bis (mercaptomethyl) benzene, 1,3,5-tris (mercaptomethyl) benzene, toluene-3,4-dithiol.

  Examples of the polyamine compound used as the chain extender include aliphatic polyamines such as ethylenediamine, 1,2-propylenediamine, 1,6-hexamethylenediamine, isophoronediamine, bis (4-aminocyclohexyl) methane, piperazine, and meta Aromatic polyamines such as (or para) xylylenediamine are listed.

  Furthermore, aliphatic or aromatic amino alcohols such as 2-ethanolamine, N-methyldiethanolamine, N-phenyldipropanolamine, hydroxyalkylsulfamides such as hydroxyethylsulfamide, hydroxyethylaminoethylsulfamide, , 2-mercaptoethanol, 1,2-dihydroxy-3-mercaptopropane, 2,3-dimercapto-1-propanol, 4-mercaptophenol and other mercapto alcohols, aminoethyl mercaptan, 2-aminothiophenol, 3-amino Amino thiols such as thiophenol and 4-aminothiophenol, urea, water and the like can also be mentioned as chain extenders.

  In addition, in the polythiourethanization reaction, instead of a part (50% by mass or less) of the poly (trithiocarbonate) polythiol, obtained from a polycarbonate polyol obtained from a polyol compound and a carbonate compound, or from a polythiol compound and a carbonate compound. The poly (dithiocarbonate) polythiol to be used may be used alone or in combination.

  Examples of the polyol compound used as a raw material for the polycarbonate polyol include ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentane. Diol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, neopentyl glycol, 3-methyl-1,5-pentane Diol, 3,3-dimethylol heptane, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,4-bis (hydroxyethyl) cyclohexane, 2-hydroxyethyl ether, 2-hydroxymethyl sulfide, 2, 5-bis (hydroxymethyl) -1,4 Dioxane, 2,5-bis (hydroxymethyl) -1,4-dithiane, trimethylol ethane, trimethylol propane, and aliphatic polyols such as pentaerythritol,

  Catechol, resorcinol, hydroquinone, 1,3,5-benzenetriol, 1,2-bis (hydroxymethyl) benzene, 1,3-bis (hydroxymethyl) benzene, 1,4-bis (hydroxymethyl) benzene, 1, Aromatic polyols such as 3,5-tris (hydroxymethyl) benzene are exemplified. Moreover, the same thing as the polythiol compound used as the raw material of poly (trithiocarbonate) polythiol is mentioned as the polythiol compound used as the raw material of poly (dithiocarbonate) polythiol.

  The polythiourethanization reaction can be carried out in the absence of a solvent or in the presence of a solvent inert to isocyanate groups and / or isothiocyanate groups.

  In the case of a solvent-free reaction, polyisocyanate compound and / or polyisothiocyanate compound are mixed with poly (trithiocarbonate) polythiol (sometimes mixed with chain extender) and the whole amount is reacted in one step. Alternatively, after reacting poly (trithiocarbonate) polythiol with polyisocyanate and / or polyisothiocyanate to obtain a prepolymer having an isocyanate group and / or isothiocyanate group, this is mixed and reacted with a chain extender. Alternatively, a prepolymer having a mercapto group was obtained by mixing and reacting a part of polyisocyanate and / or polyisothiocyanate with poly (trithiocarbonate) polythiol (mixed with a chain extender in some cases). After that, the remaining polyisocyanate and Or polyisothiocyanate by mixing and reaction can be carried out polythiourethane reaction. The reaction temperature in the absence of a solvent is preferably 20 to 100 ° C. In the case of passing through a prepolymer, a low molecular weight prepolymer is obtained, and this is heated to have a high molecular weight.

  In the case of a reaction in the presence of a solvent, poly (trithiocarbonate) polythiol is dissolved in a solvent (mixed with a chain extender in some cases), and then mixed with polyisocyanate and / or polyisothiocyanate to make the whole amount one step. Or a poly (trithiocarbonate) polyol is dissolved in a solvent, and a polyisocyanate and / or polyisothiocyanate is mixed and reacted to obtain a prepolymer having an isocyanate group and / or an isothiocyanate group. Then, this is mixed and reacted with a chain extender, or after poly (trithiocarbonate) polythiol is dissolved in a solvent (mixed with a chain extender in some cases), it is then added to a polyisocyanate and / or a polyisothene. A prepoly having a mercapto group by mixing and reacting a part of thiocyanate After obtaining the chromatography, by further mixing and reacting the residual polyisocyanate and / or polyisothiocyanate it can be performed polythiourethane reaction. The reaction temperature in the presence of a solvent is preferably 60 to 150 ° C. Typical examples of the solvent include methyl ethyl ketone, ethyl acetate, toluene, dioxane, dimethylformamide, dimethylacetamide, dimethyl sulfoxide and the like.

  In the polythiourethanization reaction, the ratio of the poly (trithiocarbonate) polythiol and the chain extender used is preferably in the range of 0 to 10 mol of the latter with respect to 1 mol of the former. It is determined appropriately depending on the physical properties of the polythiourethane. The polyisocyanate and / or polyisothiocyanate should be used so that the total amount of isocyanate groups and isothiocyanate groups is approximately equimolar to the total amount of poly (trithiocarbonate) polythiol and chain extender active hydrogen. Is preferred. Specifically, the total amount of active hydrogen contained in the poly (trithiocarbonate) polythiol and the chain extender: the total amount of isocyanate groups and isothiocyanate groups is 1: 0.8 to 1: 1.2 in an equivalent ratio. Furthermore, it is preferable to use polyisocyanate and / or polyisothiocyanate so as to be 1: 0.95 to 1: 1.05. In the polythiourethanization reaction, a known amine-based or tin-based catalyst used in a normal polyurethane-forming reaction may be used to accelerate the reaction.

  The polythiourethane thus obtained may have a molecular end that may be a mercapto group or an isocyanate group and / or an isothiocyanate group, or a chain extender end group (such as a mercapto group, a hydroxyl group, or an amino group). When the poly (trithiocarbonate) polythiol is poly (trithiocarbonate) dithiol, the polythiourethane has, for example, a repeating unit represented by the general formula (2), where “n "Represents an integer greater than or equal to 1 representing the degree of polymerization of poly (trithiocarbonate) dithiol and is related to its molecular weight.

  The polythiourethane of the present invention is a compound having at least two hydrogen atoms that react with an isocyanate group and / or an isothiocyanate group (polythiol, polyamine, etc.), or a molecular end group such as a mercapto group, a hydroxyl group, an amino group, etc. By further reacting with a compound having at least two functional groups and / or substituents (carboxyl group, halo group, etc.) that react with the polymer, it can be made high molecular weight or reticulated. Furthermore, various known additives may be added to and mixed with the polythiourethane as long as the effect is not impaired. Examples of the various additives include poly (thio) esters, poly (thio) ethers, polyamides, polymethacrylates, polyolefins, and polycarbonates.

<Component (b-2): Polyepithio compound and poly (trithiocarbonate) polythioether>
The polythioether of the present invention is obtained by polymerizing component (a): the poly (trithiocarbonate) polythiol (particularly poly (trithiocarbonate) dithiol) and component (b-2): polyepithio compound as follows. That is, it can be obtained by subjecting a polymerizable composition comprising the poly (trithiocarbonate) polythiol and the polyepithio compound to a polymerization reaction. The polyepithio compound can be used alone or in combination, and is preferably contained in the composition in an amount of 50 to 99% by weight, more preferably 65 to 95% by weight. The poly (trithiocarbonate) polythiol is preferably contained in the composition in an amount of 1 to 40% by weight, more preferably 5 to 35% by weight.

  At this time, the ratio of mercapto group to epithio group (mercapto group / epithio group; molar basis) is 0.3 or less, more preferably 0.2 or less, especially 0.1 or less, 0.001 or more, More preferably, it is 0.003 or more, particularly 0.005 or more. In addition, when the polymerizable composition further includes at least one of a mercapto group-containing compound, a mercapto group-containing organic acid, and a mercapto group-containing amine compound among other components described later, the mercapto group and poly (tri (tri-valent)) contained in these compounds. The total of mercapto groups possessed by (thiocarbonate) polythiol preferably satisfies this range. When these compounds are contained, the mercapto group possessed by the poly (trithiocarbonate) polythiol is at least 10 mol%, more preferably at least 30 mol%, particularly the mercapto groups possessed by these compounds and the poly (trithiocarbonate) polythiol, It is preferable that it is 50 mol% or more.

  The polyepithio compound is not particularly limited as long as it has a plurality of epithio groups capable of reacting with the mercapto group of poly (trithiocarbonate) polythiol to give the polythioether of the present invention. For example (wherein EP represents a β-epithiopropyl group), bis (EP) ether, bis (EP-oxy) methane, 1,2-bis (EP-oxy) ethane, 1,2-bis (EP- Oxy) propane, 1,3-bis (EP-oxy) propane, 1,2-bis (EP-oxymethyl) propane, 1- (EP-oxy) -2- (EP-oxymethyl) propane, 1,3 -Bis (EP-oxy) butane, 1,4-bis (EP-oxy) butane, 1- (EP-oxy) -3- (EP-oxymethyl) butane, 1,5-bis (EP-oxy) pentane 1- (EP-oxy) -4- (EP-oxymethyl) pentane, 1,6-bis (EP-oxy) hexane, 1- (EP-oxy) -2- (EP-oxymethyl) hexane, etc. Chain aliphatic die containing oxygen atoms Thio compounds and,

  Bis (EP) sulfide, bis (EP) disulfide, bis (EP-thio) methane, 1,2-bis (EP-thio) ethane, 1,2-bis (EP-thio) propane, 1,3-bis ( EP-thio) propane, 1,3-bis (EP-thio) -2-methylpropane, 1,3-bis (EP-thio) butane, 1,4-bis (EP-thio) butane, 1,4- Bis (EP-thio) -2-methylbutane, 1,5-bis (EP-thio) pentane, 1,5-bis (EP-thio) -2-methylpentane, 1,5-bis (EP-thio)- Such as 3-thiapentane, 1,6-bis (EP-thio) hexane, 1,6-bis (EP-thio) -2-methylhexane, 3,8-bis (EP-thio) -3,6-dithiaoctane, etc. Chain aliphatic diepithio compounds containing sulfur atoms,

  1,1,1-tris (EP-oxymethyl) propane, 1,2,3-tris (EP-thio) propane, 2,2-bis (EP-thiomethyl) -1- (EP-thio) butane, , 5-bis (EP-oxy) -2- (EP-oxymethyl) -3-thiapentane, 1,5-bis (EP-thio) -2- (EP-thiomethyl) -3-thiapentane, 1- (EP -Oxy) -2,2-bis (EP-oxymethyl) -4-thiahexane, 1- (EP-thio) -2,2-bis (EP-thiomethyl) -4-thiahexane, 1,8-bis (EP -Oxy) -4- (EP-oxymethyl) -3,6-dithiaoctane, 1,8-bis (EP-thio) -4- (EP-thiomethyl) -3,6-dithiaoctane, or other oxygen atom or sulfur atom A chain aliphatic triepithio compound containing

  Tetrakis (EP-oxymethyl) methane, 1,1,2,2-tetrakis [2- (EP-thio) ethylthiomethyl] ethane, 1,1,1-tris [2- (EP-thio) ethylthiomethyl ] -2- (EP-thio) ethane, 2,2-bis (EP-thio) -1,3-bis (EP-thiomethyl) propane, 1,5-bis (EP-oxy) -2,4-bis (EP-oxymethyl) -3-thiapentane, 1,5-bis (EP-thio) -2,4-bis (EP-thiomethyl) -3-thiapentane, 1,5,6-tris (EP-oxy)- 4- (EP-oxymethyl) -3-thiahexane, 1,8-bis (EP-oxy) -4,5-bis (EP-oxymethyl) -3,6-dithiaoctane, 1,8-bis (EP- Thio) -4,5-bis (EP-thiomethyl) -3 6-dithiaoctane, 1,8-bis (EP-oxy) -4,4-bis (EP-oxymethyl) -3,6-dithiaoctane, 1,8-bis (EP-thio) -4,4-bis ( EP-thiomethyl) -3,6-dithiaoctane, 1,8-bis (EP-oxy) -2,5-bis (EP-oxymethyl) -3,6-dithiaoctane, 1,8-bis (EP-thio) -2,5-bis (EP-thiomethyl) -3,6-dithiaoctane, 1,9-bis (EP-oxy) -5- (EP-oxymethyl) -5- [2- (EP-oxy) ethoxymethyl ] -3,7-dithianonane, 1,10-bis (EP-oxy) -5,6-bis [2- (EP-oxy) ethoxy] -3,6,9-dithiadecane, 1,11-bis (EP -Oxy) -4,8-bis (EP-oxymethyl) -3,6,9-trithiaundecane, 1,11-bis (EP-thio) -4,8-bis (EP-thiomethyl) -3,6,9-trithiaundecane, 1,11-bis (EP -Oxy) -4,7-bis (EP-oxymethyl) -3,6,9-trithiaundecane, 1,11-bis (EP-thio) -4,7-bis (EP-thiomethyl) -3, 6,9-trithiaundecane, 1,11-bis (EP-oxy) -5,7-bis (EP-oxymethyl) -3,6,9-trithiaundecane, 1,11-bis (EP-thio) ) -5,7-bis (EP-thiomethyl) -3,6,9-trithiaundecane, etc., a chain aliphatic tetraepithio compound containing an oxygen atom or sulfur atom,

  1,8-bis (EP-oxy) -2,4,5-tris (EP-oxymethyl) -3,6-dithiaoctane, 1,8-bis (EP-thio) -2,4,5-tris ( EP-thiomethyl) -3,6-dithiaoctane and the like, a chain aliphatic pentaepithio compound containing an oxygen atom or a sulfur atom,

  1,3-bis (EP-oxy) cyclohexane, 1,3-bis (EP-thio) cyclohexane, 1,4-bis (EP-oxy) cyclohexane, 1,4-bis (EP-thio) cyclohexane, 1, 3-bis (EP-oxymethyl) cyclohexane, 1,3-bis (EP-thiomethyl) cyclohexane, 1,4-bis (EP-oxymethyl) cyclohexane, 1,4-bis (EP-thiomethyl) cyclohexane, bis [ Cyclic groups containing oxygen or sulfur atoms such as 4- (EP-oxy) cyclohexyl] methane, 2,2-bis [4- (EP-oxy) cyclohexyl] propane, bis [4- (EP-oxy) cyclohexyl] sulfide Aliphatic polyepithio compounds,

  2,5-bis (EP-oxymethyl) -1,4-dithiane, 2,5-bis (EP-thiomethyl) -1,4-dithiane, 2,5-bis (EP-oxyethyloxymethyl) -1 , 4-dithiane, 2,5-bis [2- (EP-thio) ethylthiomethyl] -1,4-dithiane and other cyclic aliphatic polyepithio compounds containing a heterocycle,

  1,3-bis (EP-oxy) benzene, 1,4-bis (EP-oxy) benzene, 1,3-bis (EP-oxymethyl) benzene, 1,4-bis (EP-oxymethyl) benzene, 1,3-bis (EP-thio) benzene, 1,4-bis (EP-thio) benzene, 1,3-bis (EP-thiomethyl) benzene, 1,4-bis (EP-thiomethyl) benzene, bis [ 4- (EP-thio) phenyl] methane, 2,2-bis [4- (EP-thio) phenyl] propane, 4,4′-bis (EP-thio) biphenyl, bis [4- (EP-thio) And aromatic polyepithio compounds such as phenyl] sulfone.

  Furthermore, mercapto group-containing epithio compounds such as 3-mercaptopropylene sulfide and 4-mercaptobutene sulfide are also exemplified as the polyepithio compound. Among these polyepithio compounds, the above-mentioned various chain or cyclic aliphatic polyepithio compounds are preferable.

  In addition to the poly (trithiocarbonate) polythiol and the polyepithio compound, the polymerizable composition may include a compound having at least one functional group capable of ring-opening reaction with an epithio group. These compounds can be used alone or in combination, and are preferably contained in the polymerizable composition in an amount of 0 to 20% by weight, more preferably 0 to 7% by weight.

  Examples of the compound having at least one functional group capable of ring-opening reaction with an epithio group include a mercapto group-containing compound (excluding the mercapto group-containing epithio compound, a mercapto group-containing organic acid, and a mercapto group-containing amine compound), an amine compound , Vinyl group-containing compounds, organic acids or anhydrides thereof, mercapto group-containing organic acids, mercapto group-containing amine compounds, phenol compounds, and the like. Among these compounds, a mercapto group-containing compound, an amine compound, a mercapto group-containing amine compound, and a phenol compound are preferable, and among them, aliphatic compounds are more preferable.

  The mercapto group-containing compound is not particularly limited as long as it is a compound having at least one mercapto group capable of ring-opening reaction with an epithio group. For example, methyl mercaptan, ethyl mercaptan, 1,2-ethanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 1,5-pentanedithiol, 1,6-hexanedithiol, 1,7-heptanedithiol, 1,8-octanedithiol, 1,9-nonanedithiol, 1,10-decanedithiol, 1,12-dodecanedithiol, 2,2-dimethyl-1,3-propanedithiol, 3- Methyl-1,5-pentanedithiol, 2-methyl-1,8-octanedithiol, 1,1,1-tris (mercaptomethyl) ethane, 2-ethyl-2-mercaptomethyl-1,3-propanedithiol, tetrakis (Mercaptomethyl) methane, 1,4-cyclohexanedithiol, 1,4- Scan (mercaptomethyl) mercapto group-containing aliphatic hydrocarbon compounds such as cyclohexane (including alicyclic) or,

  Bis (2-mercaptoethyl) ether, bis (2-mercaptoethyl) sulfide, bis (2-mercaptoethyl) disulfide, 2,5-bis (mercaptomethyl) -1,4-dioxane, 2,5-bis (mercapto) A heteroatom in a carbon chain such as methyl) -1,4-dithiane, 3,3′-thiobis (propane-1,2-dithiol), 2,2′-thiobis (propane-1,3-dithiol) Mercapto group-containing aliphatic hydrocarbon compounds (including alicyclic),

  Thiophenol, 1,2-benzenedithiol, 1,3-benzenedithiol, 1,4-benzenedithiol, 1,3,5-benzenetrithiol, toluene-3,4-dithiol, mercaptomethylbenzene, 1,2- Mercapto group-containing aromatic hydrocarbons such as bis (mercaptomethyl) benzene, 1,3-bis (mercaptomethyl) benzene, 1,4-bis (mercaptomethyl) benzene, 1,3,5-tris (mercaptomethyl) benzene Compound etc. are mentioned. Furthermore, this mercapto group-containing compound also includes poly (dithiocarbonate) polythiol having a number average molecular weight of 200 to 2500 obtained by transesterification of a carbonate compound and a polythiol compound. Among these mercapto group-containing compounds, those having 8 or less, more preferably 6 or less mercapto groups are preferred, and aliphatic ones are more preferred.

  The amine compound is not particularly limited as long as it is a compound having at least one amino group capable of undergoing a ring-opening reaction with an epithio group, and examples thereof include an aliphatic primary or secondary amine, an aromatic primary or secondary amine, and the like. It is done. Examples of aliphatic primary amines include alkylamines such as ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, decylamine, laurylamine (including isomers), cyclopentylamine, Cycloalkylamines such as cyclohexylamine, 2,3-dimethylcyclohexylamine, aminomethylcyclohexane, aminomethylbicycloheptane, ethylenediamine, 1,2-propylenediamine, 1,6-hexamethylenediamine, isophoronediamine, bis (4- And alkylene diamines such as aminocyclohexyl) methane and 2,7-diaminofluorene.

  Examples of the aliphatic secondary amine include diethylamine, dipropylamine, dibutylamine (including isomers), di (2-ethylhexyl) amine, dicyclohexylamine, piperidine, pyrrolidine, piperazine, 2-methylpiperazine, 2 , 5-dimethylpiperazine, 2,6-dimethylpiperazine, 1,1-di (4-piperidyl) methane, 1,2- (4-piperidyl) ethane, 1,3- (4-piperidyl) propane, 1,4 -Di (4-piperidyl) butane etc. are mentioned.

  As the aromatic primary amine, aniline, benzylamine, phenethylamine, m- (or p-) xylylenediamine, 1,5- (or 1,8-, 2,3-) diaminonaphthalene, 2,3 -(Or 2,6-, 3,4-) diaminopyridine and the like are mentioned, and examples of the aromatic secondary amine include diphenylamine, dibenzylamine, N-methylbenzylamine, N-ethylbenzylamine and the like.

  The vinyl group-containing compound is not particularly limited as long as it is a compound having at least one vinyl group capable of ring-opening reaction with an epithio group. For example, allyl compounds such as diallyl phthalate, diallyl terephthalate, diallyl carbonate, allylamine, diallylamine, N-methylallylamine, vinyl compounds such as divinylbenzene, benzyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di ( Examples include (meth) acrylate compounds such as (meth) acrylate, neopentyl glycol di (meth) acrylate, bisphenol A di (meth) acrylate, and trimethylolpropane tri (meth) acrylate. In addition, (meth) acrylate means an acrylate or a methacrylate.

  The organic acid or its anhydride is not particularly limited as long as it is a compound having at least one carboxyl group or acid anhydride group capable of ring-opening reaction with the epithio group. Examples include thiodiglycolic acid, dithiodipropionic acid, phthalic anhydride, hexahydrophthalic anhydride, methylnorbornenoic anhydride, methylnorbornanoic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, etc. .

  The mercapto group-containing organic acid is not particularly limited as long as it is a compound having at least one mercapto group and carboxyl group capable of ring-opening reaction with an epithio group. Examples thereof include thioacetic acid, 3-mercaptopropionic acid, thioglycolic acid, thiolactic acid, thiomalic acid, thiosalicylic acid, and the like.

  The mercapto group-containing amine compound is not particularly limited as long as it is a compound having at least one mercapto group and amino group capable of ring-opening reaction with an epithio group. For example, aminoethyl mercaptan, 2-aminothiophenol, 3-aminothiophenol, 4-aminothiophenol and the like can be mentioned.

  The phenol compound is not particularly limited as long as it is a compound having at least one phenolic hydroxyl group capable of ring-opening reaction with an epithio group. For example, phenol, o-cresol, m-cresol, p-cresol, 3-methoxyphenol, catechol, resorcin, hydroquinone, pyrogallol and the like can be mentioned.

  As described above, the polymerizable composition of the present invention includes poly (trithiocarbonate) polythiol and a polyepithio compound, and includes a compound having at least one functional group capable of ring-opening reaction with the epithio group. May be. The ratio of each component in the composition is as described above. In addition, the composition may further contain a catalyst. Various additives such as an internal mold release agent, a light stabilizer, an ultraviolet absorber, an antioxidant, a paint, and a filler may be used depending on the purpose. It may be included as long as the effects of the invention are not impaired.

  Polymerization reaction of poly (trithiocarbonate) polythiol and polyepithio compound may be carried out, for example, by subjecting the polymerizable composition to −100 ° C. to 120 ° C., preferably −10 ° C. to 80 ° C. in the presence or absence of a catalyst, More preferably, the mixture is preliminarily polymerized by mixing at 0 to 50 ° C. for about 0.1 to 72 hours, and then poured into a glass or metal mold, and 10 to 200 ° C., preferably 10 to 160 ° C., more preferably It can carry out by heating to 10-130 degreeC, heating up gradually over 6 to 72 hours. The reaction pressure is not particularly limited, and may be ordinary pressure, and the reaction atmosphere is not particularly limited. The catalyst may be used as necessary within a range in which the polymerization reaction can be controlled, and the amount used may be, for example, 5% by weight or less (further 1% by weight or less) based on the polymerizable composition.

  The components in the polymerizable composition may be mixed at the same time or may be mixed stepwise during the reaction. For example, poly (trithiocarbonate) polythiol, a polyepithio compound and, if necessary, a compound having at least one functional group capable of ring-opening reaction with an epithio group are mixed and prepolymerized, and then a catalyst is added to increase the The molecular weight can be increased. In addition, after a poly (trithiocarbonate) polythiol, an epithio compound, and a catalyst are first mixed and subjected to a prepolymerization reaction, other components can be added and mixed.

  Examples of the catalyst include amines, phosphine, organic quaternary ammonium salts, organic quaternary phosphonium salts, tertiary sulfonium salts, secondary iodonium salts, mineral acids, Lewis acids, organic acids, silicic acids, and tetrafluoroboric acids. Etc. Among them, tertiary amines such as triethylamine, tributylamine, N, N-dimethylcyclohexylamine, N, N-dicyclohexylmethylamine, trimethylphosphine, triethylphosphine, tributylphosphine, tricyclohexylphosphine, triphenylphosphine Such as tertiary phosphine, tetramethylammonium chloride, tetramethylammonium bromide, tetra-n-butylammonium chloride, tetra-n-butylammonium bromide, etc., organic quaternary ammonium halides, tetramethylphosphonium chloride, tetramethylphosphonium bromide, tetra -Organic quaternary phosphonium halides such as n-butylphosphonium chloride and tetra-n-butylammonium bromide The reaction was controlled easily preferred.

  Hereinafter, the present invention will be specifically described with reference to examples. The physical properties of poly (trithiocarbonate) dithiol, polythiourethane and polythioether were measured by the following methods.

[Physical properties of poly (trithiocarbonate) dithiol]
1) Mercapto group value (SH value; mgKOH / g): A sample is weighed into a 100 mL sample bottle (weight is accurately read to the fourth decimal place in grams), and acetic anhydride-tetrahydrofuran solution (acetic anhydride in 100 mL of the solution). 4 mL) and 5 mL of 4-dimethylaminopyridine-tetrahydrofuran solution (containing 1 g of 4-dimethylaminopyridine in 100 mL of solution) were added accurately to completely dissolve the sample, and then left at room temperature for 1 hour. Subsequently, 1 mL of ultrapure water was accurately added and left at room temperature for 30 minutes with occasional stirring and titrated with a 0.25M potassium hydroxide-ethanol solution (indicator: phenolphthalein). The SH value was calculated by the following formula.

SH value (mgKOH / g) = 14.025 × (BA) × f / S
(Wherein, S is the amount of sample collected (g), A is the amount of 0.25M potassium hydroxide-ethanol solution required for titration of the sample (mL), and B is 0.25M hydroxide required for the blank test. (Amount of potassium-ethanol solution (mL), f represents a factor of 0.25M potassium hydroxide-ethanol solution)

2) Number average molecular weight (M _n ): calculated by the following formula.
M _n = 112200 / SH value

  3) Acid value (mgKOH / g): The sample was dissolved in 200 mL of toluene-ethanol solution (equal volume mixed solution) and titrated with 0.1 M potassium hydroxide-ethanol solution (indicator: phenolphthalein). Calculated.

Acid value (mgKOH / g) = 5.61 (C−D) f ′ / S ′
(In the formula, S ′ is the amount of sample collected (g), C is the amount of 0.1M potassium hydroxide-ethanol solution required for titration of the sample (mL), and D is 0.1M water required for the blank test. (Amount of potassium oxide-ethanol solution (mL), f ′ represents a factor of 0.1M potassium hydroxide-ethanol solution)

  4) Melting point and crystallization temperature: using a differential scanning calorimeter (manufactured by Shimadzu Corporation; DSC-50), in a nitrogen gas atmosphere in the range of −100 ° C. to 100 ° C., the temperature rising / falling rate is 10 ° C./min. Measured with

  5) Viscosity (mPa · sec): Measured at 100 ° C. using an E-type rotational viscometer (Brookfield; programmable digital viscometer DV-II +).

6) Ratio (%) of aryloxy group in terminal group: The ratio (molar basis) of phenoxy group to all terminal groups was determined from the integrated value of ¹ H-NMR.

7) Ratio of thioether structure (%): The total amount of the remaining thiocarbonate structure and the thioether structure generated by the de-CS ₂ reaction was determined from the integrated value of ¹ H-NMR, and the ratio of the thioether structure to the total amount (molar basis). )

  8) Residual catalyst amount (ppm; weight basis): Prepare a 30 wt% chloroform solution of polythiocarbonate dithiol, extract tetrabutylammonium hydroxide in the same volume of water and measure by high performance liquid chromatography did.

[Physical properties of polythiourethane]
1) Tensile properties: measured in accordance with JIS-K7311 using a tensile tester (Orientec; Tensilon UCT-5T) under conditions of 23 ° C. and 50% RH, initial elastic modulus, tensile stress (100%, (Value at 200% elongation), tensile strength, elongation at break.

2) Permanent elongation: According to JIS-K7312, using a tensile tester (Orientec; Tensilon UCT-5T), the test piece was stretched to 100% under the conditions of 23 ° C. and 50% RH and held for 10 minutes. . Next, after rapidly contracting this without rebounding (return speed 500 mm / min), the specimen is removed from the chuck and allowed to stand for 24 hours, and the length L between the marked lines (however, the length before extension) Is _L0 ) and calculated from the following equation. Here, L ₀ was set to 40 mm. Permanent elongation (%) = (L−L ₀ ) × 100 / L ₀

  3) Refractive index: Using a refractometer (Abago Abbe refractometer; MR-04), the refractive index when irradiated with e-line (λ = 546 nm) was measured.

4) Abbe number (ν _e ): Refractive index when irradiated with e-line (λ = 546 nm), F′-line (λ = 480 nm), C′-line (λ = 644 nm) using the above refractometer. n _e , n _{F ′} , n _{C ′} ) were measured and calculated according to the following equations.
ν _e = ( _ne −1) / (n _{F ′} −n _{C ′} )
[Physical properties of polythioether]
1) Bending properties: measured using a three-point bending tester (Orientec; Tensilon UCT-5T) at 23 ° C. and 50% RH in accordance with JIS-K7171, bending elastic modulus, bending strength, bending The fracture strain was determined. The size of the test piece was 25 mm in width, 40 mm in length, and 1 mm in thickness, the distance between the support tables was 32 mm, and the radius of the indenter and the support table was 5.0 mm and 2.0 mm, respectively.

  2) Refractive index: Using a refractometer (Abago Abbe refractometer; MR-04), the refractive index when irradiated with e-line (λ = 546 nm) was measured.

3) Abbe number (ν _e ): Using the above refractometer, the refractive index when irradiated with e-line (λ = 546 nm), F′-line (λ = 480 nm), C′-line (λ = 644 nm) ( n _e , n _{F ′} , n _{C ′} ) were measured and calculated according to the following equations.
ν _e = ( _ne −1) / (n _{F ′} −n _{C ′} )

4) Glass transition temperature (T _g ): Using a differential scanning calorimeter (Perkin Elmer; PYRIS Diamond DSC), in a nitrogen gas atmosphere in the range of −100 ° C. to 100 ° C., the temperature rising and cooling rate is 10 ° C. Measured at / min.

[Reference Example 1]
[Production of poly (trithiocarbonate) dithiol]
A glass reactor having an internal volume of 500 mL (milliliter) equipped with a stirrer, a thermometer, and a distillation column (equipped with a fractionation tube, a reflux head, and a condenser at the top) was charged with 98.2 g of bis (2-mercaptoethyl) sulfide. (0.636 mol), 97.5 g (0.423 mol) of diphenylthiocarbonate, 0.3701 g (0.143 mmol) of a 10 wt% tetrabutylammonium hydroxide-methanol solution, 200 mmHg (27 kPa), 160 ° C. And kept at reflux for 1 hour. Next, the pressure was gradually reduced to 30 mmHg (4.0 kPa) over 5 hours while distilling off the phenol, and when the phenol stopped distilling, the pressure was gradually reduced to 7 mmHg (0.93 kPa) over 1.5 hours. The mixture was further held at 7 mmHg for 3 hours, and reacted while distilling phenol to produce the desired poly (trithiocarbonate) dithiol.

To the poly (trithiocarbonate) dithiol, equimolar amount of p-toluenesulfonic acid monohydrate was added to the catalyst, and the mixture was stirred at 100 mHg (13 kPa) at 130 ° C. for 2 hours to inactivate the catalyst. Next, 280 g of methylene chloride was added to dissolve the poly (trithiocarbonate) dithiol, and the solution was washed three times with the same amount of water, and then dried over anhydrous magnesium sulfate. Methylene was distilled off. The physical properties and ¹ H-NMR measurement results of the obtained poly (trithiocarbonate) dithiol are shown below. In addition, SH value corresponded with the measurement result of ¹ H-NMR.

  SH value: 180.0 (mg KOH / g), number average molecular weight: 623, acid value: 0.10 (mg KOH / g), viscosity: 132 (mPa · sec), melting point: 44.8 ° C., crystallization temperature: −100 ° C. or less (not measurable), terminal aryloxy group: less than 1%, thioether structure: less than 1%, residual catalyst: less than 2 ppm

δ (ppm): 1.73 (t, J = 7.9 Hz, SH), 1.75 (t, J = 7.9 Hz, SH), 2.83 (m, CH ₂ SCH ₂ and CH ₂ SH) 3.58 (t, J = 7.9 Hz, CH ₂ SCS), 3.61 (t, J = 7.9 Hz, CH ₂ SCS)

[Example A-1]
[Manufacture of polythiourethane]
In a 300 mL glass reactor equipped with a stirrer, thermometer, and condenser, 39.96 g (64.11 mmol) of poly (trithiocarbonate) dithiol obtained in Reference Example 1 was added to 153 g of dimethylacetamide. The solution was completely dissolved at 0 ° C., and 11.17 g (64.14 mmol) of 2,4-tolylene diisocyanate was added at this temperature and reacted for 3 hours. Next, 0.335 g (1.92 mmol) of 2,4-tolylene diisocyanate was further added to the reaction solution and reacted at 80 ° C. When the increase in viscosity almost disappeared (after 4 hours), the reaction was performed. Stopped. The final viscosity of the solution was 20.9 Pa · sec at 50 ° C. The obtained solution (polythiourethane solution) is heated to 60 ° C., then cast on a releasable glass plate, heat-treated at 60 ° C. for 2 hours, and then at 110 ° C. for 3 hours to form a film having a thickness of about 200 μm (I) was obtained. The physical properties of this film are shown in Table 1.

[Comparative Example A-1]
[Manufacture of polythiourethane]
In a reactor similar to Example A-1, 19.22 g (124.5 mmol) of bis (2-mercaptoethyl) sulfide was completely dissolved in 162 g of dimethylacetamide at 35 ° C. After adding 21.69 g (124.5 mmol) of range isocyanate, the temperature of the reaction solution was maintained at 70 ° C. for 3 hours. Next, 0.650 g (3.73 mmol) of 2,4-tolylene diisocyanate was further added to the reaction solution and reacted at 80 ° C., and the reaction was carried out when almost no increase in viscosity was observed (after 12 hours). Stopped. The final viscosity of the solution was 50.1 Pa · sec at 50 ° C. The obtained solution (polythiourethane solution) was treated in the same manner to obtain a film (II) having a thickness of about 200 μm. The physical properties of this film are shown in Table 1.

[Comparative Example A-2]
[Manufacture of polythiourethane]
In the same reactor as in Example A-1, 20.42 g (135.9 mmol) of 1,6-hexanedithiol was completely dissolved in 180 g of dimethylacetamide at 35 ° C. and at this temperature 2,4-tolylene diisocyanate. After 23.66 g (135.9 mmol) was added, the reaction mixture was kept at 70 ° C. for 3 hours. Next, 0.69 g (3.96 mmol) of 2,4-tolylene diisocyanate was further added to the reaction solution and reacted at 80 ° C. When the viscosity almost disappeared (after 8 hours), the reaction was performed. Stopped. The final viscosity of the solution was 20.3 Pa · sec at 50 ° C. The obtained solution (polythiourethane solution) was treated in the same manner to obtain a film (III) having a thickness of about 200 μm. The physical properties of this film are shown in Table 1.

[Comparative Example A-3]
[Production of polyurethane]
In the same reactor as in Example A-1, 39.90 g (79.98 mmol) of polycarbonate diol (UH-CARB50; manufactured by Ube Industries, hydroxyl value 224.9 mgKOH / g) was completely dissolved in 162 g of dimethylacetamide at 70 ° C. At this temperature, 13.93 g (79.98 mmol) of 2,4-tolylene diisocyanate was added and reacted for 5 hours. Next, 0.400 g (2.30 mmol) of 2,4-tolylene diisocyanate was further added to the reaction solution, and the mixture was reacted at 80 ° C. When the increase in viscosity almost disappeared (after 10 hours), the reaction was performed. Stopped. The final viscosity of the solution was 9.8 Pa · sec at 50 ° C. The obtained solution (polyurethane solution) was treated in the same manner to obtain a film (IV) having a thickness of about 200 μm. The physical properties of this film are shown in Table 1.

[Example B-1]
[Production of poly (trithiocarbonate) polythioether]
In a glass reactor equipped with a stirrer and having an internal volume of 30 mL, 1.54 g (2.47 mmol) of poly (trithiocarbonate) dithiol obtained in Reference Example 1 was added to bis (β-epithiopropyl) ether. 5 g (83.2 mmol) was completely dissolved at 25 ° C., 0.054 g of N, N-dimethylcyclohexylamine was added at the same temperature, and the mixture was reacted for 2 hours. Next, the reaction solution was poured into a mold in which a silicon rubber spacer having a thickness of 1 mm was sandwiched between two glass plates, allowed to stand at 25 ° C. for 12 hours, and then heated from 30 ° C. to 100 ° C. over 27 hours. The obtained polymer (referred to as polythioether (I)) was released from the mold, cut into a predetermined size, and optical and mechanical properties were measured. Table 2 shows the physical properties of the polythioether (I). Note that bis (β-epithiopropyl) ether is obtained from bis (β-epoxypropyl) ether produced from 3-epoxypropyloxypropene as a raw material according to the method described in European Journal of Organic Chemistry, 2001,875. It was produced according to the method described in Japanese Patent No. 336087.

[Comparative Example B-1]
(Production of polythioether)
In the same reactor as in Example B-1, 0.286 g (1.85 mmol) of bis (2-mercaptoethyl) sulfide was added to 8.77 g (54.1 mmol) of bis (β-epithiopropyl) ether. After complete dissolution at 0 ° C., 0.0087 g of N, N-dimethylcyclohexylamine was added at this temperature and reacted for 2 hours. Subsequently, polythioether (II) was obtained in the same manner as in Example B-1, and the optical and mechanical properties were measured. The physical properties are shown in Table 2.

[Comparative Example B-2]
(Production of polythioether)
In the same reactor as in Example B-1, 0.934 g (6.05 mmol) of bis (2-mercaptoethyl) sulfide was added to 8.30 g (51.2 mmol) of bis (β-epithiopropyl) ether at room temperature. The solution was completely dissolved at 25 ° C., 0.0346 g of N, N-dimethylcyclohexylamine was added at this temperature, and the mixture was reacted for 2 hours. Subsequently, polythioether (III) was obtained in the same manner as in Example B-1, and the optical and mechanical properties were measured. The physical properties are shown in Table 2.

A novel optical material can be obtained by the present invention. Since the polythiourethane according to one embodiment of the present invention is excellent in optical performance (high refractive index, high Abbe number) and mechanical performance (tensile properties; particularly elongation at break), plastic lenses, prisms, optical fibers, information It can be suitably used for optical materials such as a recording substrate, a colored filter, and an infrared absorption filter.
In addition, poly (trithiocarbonate) polythioethers according to different embodiments of the present invention are excellent in optical performance (refractive index, Abbe number) and mechanical performance (bending characteristics; particularly bending fracture strain) and have a high glass transition temperature. Therefore, it can be suitably used for plastic lenses, prisms, optical fibers, information recording substrates, colored filters, infrared absorption filters, and the like.

Claims (16)

Component (a): poly (trithiocarbonate) polythiol, and component (b):
Component (b-1): polyisocyanate and / or polyisothiocyanate, or
Component (b-2): Polymerized cured product obtained by reacting a polyepithio compound . The component (a) is represented by the general formula (1):

(In the formula, R represents a divalent hydrocarbon group, may have a substituent not involved in the reaction, and may contain a heteroatom or a ring structure in the carbon chain.)
2. The polymerized cured product according to claim 1, comprising a poly (trithiocarbonate) polythiol having a repeating unit represented by the formula (1) and a terminal SH group and a number average molecular weight of 300 to 2500. 3.   The polymerization hardened | cured material of Claim 1 or 2 whose polythiol compound used as the thiol component of poly (trithio carbonate) polythiol is bis (2-mercaptoethyl) sulfide.   The component (b) is component (b-1): polyisocyanate and / or polyisothiocyanate, and the polymerized cured product is a polythiourethane. The polymerized cured product has the general formula (2):

(In the formula, R is the same as described above, Y represents a divalent hydrocarbon group constituting polyisocyanate and / or polyisothiocyanate, and may have a substituent not involved in the reaction. A carbon atom may contain a hetero atom or a ring structure, X represents an oxygen atom or a sulfur atom, and n represents an integer of 1 or more.)
The polymerization cured product according to claim 4, which is a polythiourethane having a repeating unit represented by:   An optical material comprising the polythiourethane according to claim 4 or 5.   The component (b) is a component (b-2): a polyepithio compound, and the polymerized cured product is a poly (trithiocarbonate) polythioether. The polymerized cured product according to any one of claims 1 to 3.   An optical material comprising the poly (trithiocarbonate) polythioether of claim 7. Component (a): poly (trithiocarbonate) polythiol, and component (b):
Component (b-1): polyisocyanate and / or polyisothiocyanate, or
Polymerizable composition containing component (b-2): polyepithio compound . The component (a) is represented by the general formula (1):

(In the formula, R represents a divalent hydrocarbon group, may have a substituent not involved in the reaction, and may contain a heteroatom or a ring structure in the carbon chain.)
10. The polymerizable composition according to claim 9, comprising a poly (trithiocarbonate) polythiol having a repeating unit represented by formula (II) and a terminal SH group and having a number average molecular weight of 300 to 2500.   The polymerizable composition according to claim 9 or 10, wherein the polythiol compound serving as a thiol component of poly (trithiocarbonate) polythiol is bis (2-mercaptoethyl) sulfide.   The polymerizable composition according to any one of claims 9 to 11, wherein component (b) is component (b-1): polyisocyanate and / or polyisothiocyanate, and gives polythiourethane as a cured product. General formula (2):

(In the formula, R is the same as described above, Y represents a divalent hydrocarbon group constituting polyisocyanate and / or polyisothiocyanate, and may have a substituent not involved in the reaction. A carbon atom may contain a hetero atom or a ring structure, X represents an oxygen atom or a sulfur atom, and n represents an integer of 1 or more.)
The polymerizable composition of Claim 12 which gives the polythiourethane which has a repeating unit represented by these.   The polymerizable composition according to any one of claims 9 to 11, wherein the component (b) is a component (b-2): a polyepithio compound, and gives a poly (trithiocarbonate) polythioether as a polymerized cured product.   1 to 40% by weight of the component (a), 50 to 99% by weight of the component (b-2), and 0 to 0% of a compound having at least one functional group capable of ring-opening reaction with an epithio group as an optional component. The polymerizable composition according to claim 14, which is contained in an amount of 20% by weight.   An optical material obtained by curing the polymerizable composition according to claim 9.