A polysulfydryl compound, a preparation method thereof and application thereof on optical materials

Abstract

The application belongs to the field of organic compounds and the field of preparation of optical new materials, and particularly provides a polythiol compound 4,8,11-trimercaptomethyl-3,6,9,12-tetrathiatetradecane-1,14-diol, a polythiol composition prepared by using the polythiol compound, a polymerizable composition prepared by using the prepared polythiol composition, and the obtained polymerizable composition is used in the preparation of optical materials, so that the prepared optical materials have lower turbidity and yellow index. The polythiol compound is branched, and the crosslinking degree can be further increased, and the turbidity is reduced; and the existence of the hydroxyl group generates a polyurethane group during polymerization, so that the yellow index is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of organic compounds and the field of preparation of optical new materials, in particular to a kind of polythiol compound and its preparation method and application in optical material. BACKGROUND

[0002] Compared with inorganic optical materials such as glass, quartz, resin optical materials have the characteristics of light, high toughness, easy dyeing, low cost. In recent years, resin materials are rapidly popularized in optical elements such as glasses and camera lenses. In recent years, the polythioester optical resin material as an important branch of resin optical material has developed rapidly, and its high refractive index, impact resistance and easy processing are favored. This kind of resin material is mainly synthesized from polythiol compound and isocyanate.

[0003] However, the optical material made of the polythiol compound produced by the prior art has high haze and high yellow index. High haze of optical material reduces the light transmittance of the material, and high yellow index increases the chroma, which affects the optical performance of the material and cannot meet the raw material requirements for preparing excellent optical materials.

[0004] Therefore, in order to prepare excellent optical materials, it is necessary to provide high-quality raw materials, so it is of important economic value to synthesize a polythiol compound that can reduce the haze and yellow index of optical materials. SUMMARY

[0005] In order to solve the problems of unsatisfactory haze and high yellow index of optical materials prepared based on polythiol composition in the prior art, the present application provides a polythiol compound 4,8,11-trimercaptomethyl-3,6,9,12-tetra- thia tetradecane-1,14-diol, and a polythiol composition comprising the polythiol compound. When the polythiol composition is used as a polymerizable composition together with other raw materials for the preparation of optical materials, it has a lower yellow index and can effectively reduce the haze of the product.

[0006] The present application first provides a polythiol compound, which is named 4,8,11-trimercaptomethyl-3,6,9,12-tetra-thia tetradecane-1,14-diol, and its chemical structure is shown as formula I. The substance is colorless transparent oil, insoluble in water, and easily soluble in organic solvents:

[0007] .

[0008] The present application further provides a preparation method of the above-mentioned polythiol compound, which specifically comprises the following steps:

[0009] 1) drop liquid alkali solution into 2-mercaptoethanol, heat and stir to obtain a first mixture;

[0010] The solute molar ratio of the 2-mercaptoethanol to the alkali solution is (1-2):(1-2), such as 1.4:1.5;

[0011] The temperature of the incubation is 50-70℃, such as 65℃; the time of the incubation reaction is 0.5-1.5h, such as 1.0h; the stirring speed is 200-400r / min.

[0012] 2) After the first mixed solution obtained in step 1) is added with bis(3-chloro-2-hydroxypropyl) sulfide (CAS: 19030-86-5), a first reaction solution is obtained by reaction, and the product is shown as formula A;

[0013] 。

[0014] As preferred, the molar ratio of the bis(3-chloro-2-hydroxypropyl) sulfide to the 2-mercaptoethanol in step 1) is (0.3-0.7):(0.6-2), such as 0.7:0.6;

[0015] The reaction temperature is 60-80℃, such as 75℃; the reaction time is 1.5-4.5h, such as 3h.

[0016] 3) According to the same method as step 1), the same conditions, proportions and 2-mercaptoethanol quality are used to prepare a second mixed solution with the same volume.

[0017] 4) After the second mixed solution obtained in step 3) is added with 1,3-dichloro-2-propanol, a second reaction solution is obtained by reaction, and the temperature and time of the reaction are consistent with those in step 2), and the product is shown as formula B;

[0018] 。

[0019] The molar ratio of the 1,3-dichloro-2-propanol to the bis(3-chloro-2-hydroxypropyl) sulfide in step 2) is (0.8-1.2):(0.8-1.2), such as 1:1.

[0020] The first reaction solution of step 2) and the second reaction solution of step 4) are mixed, and sodium sulfide is added, and a third reaction solution is obtained by incubation and stirring reaction, and the product is shown as formula C;

[0021] 。

[0022] The molar ratio of the sodium sulfide to the bis(3-chloro-2-hydroxypropyl) sulfide is (0.8-1.2):(0.8-1.2), such as 1:1;

[0023] The reaction temperature is 60-80℃, such as 75℃; the reaction time is 1.5-4.5h, such as 2h; the stirring speed is 200-400r / min.

[0024] After adding hydrochloric acid solution and thiourea into the third reaction solution obtained in step 5), refluxing reaction is performed to obtain a fourth reaction solution, and the product is shown as formula D;

[0025] 。

[0026] The mass concentration of the hydrochloric acid is 20-38%, such as 30%;

[0027] The molar ratio of the hydrochloric acid to the sodium sulfide in step 5) is (1-5):(1-3), such as 4.3:1.0;

[0028] The molar ratio of the thiourea to the sodium sulfide in step 5) is (1-5):(1-3), such as 4.8:1.5;

[0029] The refluxing reaction temperature is 110-120℃, and the time is 5-12h, such as 8h.

[0030] 7) Adding ammonia solution into the fourth reaction solution obtained in step 6) to perform warming reaction to obtain a product containing a polysulfane compound shown as formula I;

[0031] The mass concentration of the ammonia water is 10-20%, such as 15%;

[0032] The molar ratio of ammonia in the ammonia water to the sodium sulfide in step 5) is (3-12):(1-2), such as 10:1;

[0033] The reaction temperature is 90-100℃, such as 95℃, and the time is 2-4h, such as 2h.

[0034] As preferred, the solvent of the base solution is water, the solute is one or more of lithium hydroxide, sodium hydroxide and potassium hydroxide, and the mass concentration of the base solution is 35-45%, such as 42%;

[0035] As preferred, after step 7) is completed, the product of step 7) is separated to obtain a crude product, the crude product is washed with water and an acidic solution, and then vacuum desolventization and column chromatography purification are performed to obtain the polysulfane compound shown as formula I, which is a colorless oil; the water is distilled water, the amount of water used in each washing is the same as the mass of the crude product, and the number of washing times is not less than 3, which can be 3; the acidic solution includes one or more of hydrochloric acid aqueous solution, phosphoric acid aqueous solution and sulfuric acid aqueous solution, the mass fraction of the acidic solution is 20-30%, the amount of the acidic solution used in each washing is 10% of the mass of the crude product, and the number of washing times is not less than 2, which can be 2.

[0036] The present application further provides a polythiol composition comprising the polythiol compound, the polythiol composition comprising the polythiol compound and a first polythiol composition, the first polythiol composition being a mixture of one or more than two of the compounds represented by Formula II, Formula III and Formula IV; the first polythiol composition can be prepared by using the synthetic scheme described in patent CN110446696A.

[0037]

[0038] Preferably, the mass fraction of the polythiol compound in the polythiol composition is 0.001-2.00%.

[0039] The present application further provides a polymerizable composition comprising the polythiol composition, the polymerizable composition comprising the polythiol composition and an isocyanate compound.

[0040] Preferably, the mass ratio of the polythiol composition to the isocyanate compound in the polymerizable composition is (0.7-1.1):1.

[0041] Preferably, the isocyanate compound comprises one or more of toluene diisocyanate (TDI), isophorone diisocyanate (IPDI), diphenylmethane diisocyanate (MDI), dicyclohexylmethane diisocyanate (HMDI), hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI), lysine diisocyanate (LDI) tetramethylene diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, 4,4'-diisocyanate dicyclohexylmethane, isophorone diisocyanate, norbornane diisocyanate, and xylylene diisocyanate.

[0042] The present application further provides a method for preparing an optical material using the polymerizable composition, specifically comprising: mixing the polymerizable composition with an initiator, and then performing polymerization and curing to obtain the optical material.

[0043] Preferably, the initiator is selected from one of dimethyltin dichloride, dibutyltin dilaurate, dibutyltin dichloride, and stannous octoate, and the addition amount of the initiator is 0.005-0.05% of the total mass of the polymerizable composition.

[0044] Preferably, the method for preparing an optical material comprises the following steps:

[0045] A) stirring and dissolving the isocyanate compound and the initiator to obtain a first mixed solution;

[0046] B) mixing the first mixed solution and the polythiol composition, degassing to obtain a second mixed solution;

[0047] C) pouring the second mixed solution into a mold, polymerizing and curing to obtain an optical material.

[0048] The polythiol composition is the polythiol composition described above.

[0049] In step A), the temperature for stirring and dissolving is 10-20°C, and the stirring speed is 200-400 r / min.

[0050] As a preference, a releasing agent is added in step A), and the mass ratio of the releasing agent to the isocyanate compound is (0.002-0.006):100, and the releasing agent is selected from one of alkyl polyphosphates and chloroalkyl polyphosphates.

[0051] In step B), a vacuum pump is used for degassing, and the pressure is controlled below 350 Pa, and the degassing time is 0.5-1.0 h.

[0052] In step C), the mold is a glass mold with a curved surface of 0°, a diameter of 80 mm, and a thickness of 10 mm; the polymerizing and curing temperature is 100-125°C, and the polymerizing and curing time is 2-4 h; after pouring, the mold is laid flat on a tray for temperature rising curing.

[0053] The present application provides a new polythiol compound, and uses the polythiol compound to prepare a polythiol composition, uses the prepared polythiol composition to prepare a polymerizable composition, and uses the obtained polymerizable composition to prepare an optical material, so that the prepared optical material has lower haze and yellow index. The polythiol compound has branched chains, which can further increase the crosslinking degree and reduce the haze; and the presence of hydroxyl groups generates polyurethane groups during polymerization, which can reduce the yellow index. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1 NMR detection spectrum of the first reaction liquid product prepared in Example 1;

[0055] Figure 2 NMR detection spectrum of the second reaction liquid product prepared in Example 1;

[0056] Figure 3 NMR detection spectrum of the third reaction liquid product prepared in Example 1;

[0057] Figure 4 NMR detection spectrum of the fourth reaction liquid product prepared in Example 1;

[0058] Figure 5A mass spectrometry detection spectrum of the polythiol compound 4,8,11-trimercaptomethyl-3,6,9,12-tetrathiatetradecane-1,14-diol prepared in Example 1;

[0059] Figure 6 A nuclear magnetic resonance detection spectrum of the polythiol compound 4,8,11-trimercaptomethyl-3,6,9,12-tetrathiatetradecane-1,14-diol prepared in Example 1. DETAILED DESCRIPTION

[0060] The technical solutions of the present application will be further described below in combination with specific examples, which are only used to describe the technical solutions of the present application in more detail and should not be understood as limiting the protection scope of the present application.

[0061] In some embodiments of the present application, the polythiol composition is obtained by mixing the first polythiol composition and a polythiol compound having the structure shown in Formula I.

[0062] In some embodiments of the present application, the mass fraction of the polythiol compound in the polythiol composition is 0.001-2.00%, such as 0.001%, 0.01%, 0.02%, 0.04%, 0.06%, 0.08%, 0.1%, 0.5%, 1.0%, 2.0%; and the mass fraction of the polythiol compound is preferably 0.01-1.0%.

[0063] In the embodiments of the present application, an optical material is also provided, which is prepared using a polymerizable composition and an initiator as raw materials;

[0064] The polymerizable composition for the optical material comprises the polythiol composition and an isocyanate compound;

[0065] The polythiol composition is the polythiol composition described above;

[0066] The initiator is the initiator described above, and the addition amount is 0.005-0.01% of the total mass of the polymerizable composition;

[0067] In some embodiments of the present application, the mass ratio of the polythiol composition to the isocyanate in the polythiol composition is (0.7-1.1):1, such as 0.8:1.

[0068] In some embodiments of the present application, the optical material is an optical lens.

[0069] In the embodiments of the present application, there is no special limitation on the sources of the raw materials used, and if the source or preparation method is not specifically described, it can be a general commercially available product.

[0070] The present application provides a preparation method of the optical material, comprising the following steps:

[0071] The optical material is obtained by mixing the polymerizable composition and the initiator, and then performing polymerization and curing.

[0072] In some embodiments of the present application, the preparation method of the optical material comprises the following steps:

[0073] A) stirring and dissolving the isocyanate compound and the initiator to obtain a first mixed solution;

[0074] B) mixing the first mixed solution and the polysulfane composition, and then degassing to obtain a second mixed solution;

[0075] C) pouring the second mixed solution into a mold, and then performing polymerization and curing to obtain the optical material;

[0076] The polysulfane composition is the polysulfane composition described above.

[0077] The temperature for stirring and dissolving in step A) is 10-20°C;

[0078] In step B), the degassing is performed by using a vacuum pump, and the pressure is controlled to be below 350 Pa, and the degassing time is 0.5-1.0 h;

[0079] In step C), the mold is a glass mold with a curved surface of 0°, a diameter of 80 mm, and a thickness of 10 mm; after pouring, the mold is placed on a tray for temperature rising and curing. The polymerization and curing temperature is 100-125°C, and the polymerization and curing time is 2-4 h.

[0080] The polysulfane composition provided by the present application can reduce the haze and yellow index of the optical material. By further controlling the mass fraction of the first polysulfane composition and the polysulfane compound having the structure shown in formula I, the haze and yellow index of the product can be significantly reduced.

[0081] In this embodiment, a polysulfane compound 4,8,11-trimercaptomethyl-3,6,9,12-tetrathiatetradecane-1,14-diol is first provided, and the chemical structural formula is shown in formula I:

[0082] .

[0083] In this embodiment, a preparation method of the above-mentioned compound is also provided, which comprises the following steps:

[0084] 1) A 42% mass fraction potassium hydroxide aqueous solution was added dropwise to 23 g of 2-mercaptoethanol, the molar ratio of 2-mercaptoethanol to potassium hydroxide was 1.4:1.5, and the reaction was carried out at 65°C with 200 rpm incubation stirring for 1 h to obtain a first mixed solution.

[0085] 2) The first mixed solution obtained in step 1) was added dropwise with bis(3-chloro-2-hydroxypropyl) sulfide (75 g, 0.344 mol, CAS: 19030-86-5), the molar ratio of bis(3-chloro-2-hydroxypropyl) sulfide to 2-mercaptoethanol in step 1) was 0.7:0.6, and the reaction was carried out at 75°C for 3 h to obtain a first reaction solution;

[0086] The product in the first reaction solution was detected, Figure 1 The first reaction solution product is shown in the nuclear magnetic resonance hydrogen spectrum, and the chemical formula of the product is as shown in formula A;

[0087] 。

[0088] Figure 1 The first reaction solution product nuclear magnetic detection spectrum is shown in the HNMR spectrum data as follows: 1 H NMR: δ 2.85-3.07 (8H, 2.90 (d, J = 5.2 Hz), 2.90 (d, J = 5.2 Hz), 2.92 (d, J = 6.9 Hz), 2.92 (d, J = 6.9 Hz), 2.93 (d, J = 5.8 Hz), 2.93 (d, J = 5.8 Hz), 3.01 (t, J = 6.8 Hz), 3.01 (t, J = 6.8 Hz)), 3.50-3.62 (2H, 3.56 (t, J = 6.8 Hz), 3.56 (t, J = 6.8 Hz)), 3.73-3.84 (2H, 3.78 (d, J = 5.1 Hz), 3.78 (d, J = 5.1 Hz)), 3.85-4.00 (2H, 3.92 (tt, J = 6.9, 5.8 Hz), 3.94 (q, J = 5.2 Hz)).

[0089] 3) A 42% mass fraction potassium hydroxide aqueous solution was added dropwise to 23 g of 2-mercaptoethanol, the molar ratio of 2-mercaptoethanol to potassium hydroxide was 1.4:1.5, and the reaction was carried out at 65°C with 200 rpm incubation stirring for 1 h to obtain a second mixed solution;

[0090] 4) To the second mixed solution obtained in step 3), drop 1,3-dichloro-2-propanol in an amount equimolar to the bis(3-chloro-2-hydroxypropyl) sulfide in step 1), the molar ratio of 1,3-dichloro-2-propanol to 2-mercaptoethanol in step 3) is 0.7:0.6, and react at 75°C for 3h to obtain a second reaction solution;

[0091] Detect the product in the second reaction solution, Figure 2 The figure shows the nuclear magnetic resonance hydrogen spectrum of the product in the second reaction solution, and the chemical formula of the product is as shown in formula B:

[0092] .

[0093] Figure 2 The figure shows the nuclear magnetic resonance hydrogen spectrum of the product in the second reaction solution, and the chemical formula of the product is as shown in formula B: 1 H NMR: δ 2.83-3.05 (4H, 2.89 (d, J = 5.2 Hz), 2.89 (d, J = 5.2 Hz), 2.99 (t, J = 6.4 Hz), 2.99 (t, J = 6.4 Hz)), 3.51-3.63 (2H, 3.57 (t, J = 6.4 Hz), 3.57 (t, J = 6.4 Hz)), 3.71-3.83 (2H, 3.77 (d, J = 4.8 Hz), 3.77 (d, J = 4.8 Hz)), 3.96 (1H, tt, J = 5.2, 4.8 Hz).

[0094] 5) Mix the first reaction solution of step 2 and the second reaction solution of step 4, then add sodium sulfide, the molar ratio of sodium sulfide to bis(3-chloro-2-hydroxypropyl) sulfide in step 2 is 1:1, and react at 75°C with 200 rpm for 2h to obtain a third reaction solution;

[0095] Detect the product in the third reaction solution, Figure 3 The figure shows the nuclear magnetic resonance hydrogen spectrum of the product in the third reaction solution, and the chemical formula of the product is as shown in formula C:

[0096] .

[0097] Figure 3 The figure shows the nuclear magnetic resonance hydrogen spectrum of the product in the third reaction solution, and the chemical formula of the product is as shown in formula C: 1H NMR: δ 2.87-3.06 (16H, 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 2.93 (d, J = 7.6 Hz), 3.00 (t, J = 6.6 Hz), 3.00 (t, J = 6.6 Hz), 3.00 (t, J = 6.6 Hz), 3.00 (t, J = 6.6 Hz)), 3.50-3.62 (4H, 3.56 (t, J = 6.6 Hz), 3.56 (t, J = 6.6 Hz), 3.56 (t, J = 6.6 Hz), 3.56 (t, J = 6.6 Hz)), 3.86-3.98 (3H, 3.92 (q, J = 7.6 Hz), 3.92 (q, J = 7.6 Hz), 3.92 (q, J = 7.6 Hz)).

[0098] 6) To the third reaction solution obtained in step 5), a 30% hydrochloric acid solution and thiourea were added, the molar ratio of the hydrochloric acid to sodium sulfide in step 5) was 4.3:1.0, and the molar ratio of the thiourea to sodium sulfide in step 5) was 4.8:1.5, and refluxed at 115°C for 8h to obtain a fourth reaction solution;

[0099] The product in the fourth reaction solution was detected, Figure 4 The HNMR spectrum of the product in the fourth reaction solution is shown in the figure, and the chemical formula of the product is as shown in formula D:

[0100] .

[0101] Figure 4 The HNMR spectrum of the product in the fourth reaction solution is shown in the figure, and the chemical formula of the product is as shown in formula D: 1H NMR: δ 2.98-3.28 (10H, 3.04 (t, J = 7.5 Hz), 3.04 (t, J = 7.5 Hz), 3.05 (t, J = 6.7 Hz), 3.05 (t, J = 6.7 Hz), 3.10 (d, J = 6.7 Hz), 3.10 (d, J = 6.7 Hz), 3.11 (d, J = 6.7 Hz), 3.11 (d, J = 6.7 Hz), 3.22 (d, J = 6.7 Hz), 3.22 (d, J = 6.7 Hz)), 3.48-3.81 (13H, 3.54 (d, J = 6.7 Hz), 3.54 (d, J = 6.7 Hz), 3.55 (d, J = 6.7 Hz), 3.55 (d, J = 6.7 Hz), 3.55 (d, J = 6.7 Hz), 3.55 (d, J = 6.7 Hz), 3.59 (t, J = 7.5 Hz), 3.59 (t, J = 7.5 Hz), 3.64 (q, J = 6.7 Hz), 3.64 (q, J = 6.7 Hz), 3.70 (t, J = 6.7 Hz), 3.70 (t, J = 6.7 Hz), 3.75 (q, J = 6.7 Hz)).

[0102] 7) To the fourth reaction solution obtained in step 6), 15% ammonia water solution was added, the molar ratio of NH3 in the ammonia water to sodium sulfide in step 5) was 10:1, and the temperature was raised to 95°C for 2h to obtain a product containing a polysulfydryl compound represented by formula I;

[0103] After step 7) was completed, the product of step 7) was separated to obtain 151g of a crude oil product, which was washed with distilled water of the same mass as the crude product for 3 times, and then washed with 30% mass fraction hydrochloric acid aqueous solution of 10% of the mass of the crude product for 2 times, and then vacuum desolventized and column chromatography purified to obtain the polysulfydryl compound 32g, with a yield of 21.2%.

[0104] Figure 5 The mass spectrum of the prepared polysulfydryl compound, Figure 6 The HNMR graph of the polysulfydryl compound, the prepared polysulfydryl compound is named 4,8,11-trimercaptomethyl-3,6,9,12-tetrathiatetradecane-1,14-diol, and the HNMR spectrum data is as follows: 1H NMR: δ 2.97-3.23 (16H, 3.03 (t, J = 6.7 Hz), 3.03 (t, J = 6.7Hz), 3.05 (d, J = 6.7 Hz), 3.05 (d, J = 6.7 Hz), 3.05 (t, J = 7.5 Hz), 3.05(t, J = 7.5 Hz), 3.06 (d, J = 6.7 Hz), 3.06 (d, J = 6.7 Hz), 3.07 (d, J = 6.7Hz), 3.07 (d, J = 6.7 Hz), 3.13 (d, J = 6.7 Hz), 3.13 (d, J = 6.7 Hz), 3.17(d, J = 6.7 Hz), 3.17 (d, J = 6.7 Hz), 3.18 (d, J = 6.7 Hz), 3.18 (d, J = 6.7Hz)), 3.49-3.84 (7H, 3.55 (t, J = 7.5 Hz), 3.55 (t, J = 7.5 Hz), 3.59 (q, J =6.7 Hz), 3.69 (q, J = 6.7 Hz), 3.72 (t, J = 6.7 Hz), 3.72 (t, J = 6.7 Hz),3.78 (q, J = 6.7 Hz))).

[0105] In this embodiment, a first polythiol composition is used as a raw material, which is a mixture of one or more of compounds represented by Formula II, Formula III, and Formula IV as a main component.

[0106]

[0107] In this embodiment, the above-mentioned first polythiol composition is prepared using a method known in the prior art, and specifically, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (i.e., the compound represented by Formula II), 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (i.e., the compound represented by Formula IV), and 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane (i.e., the compound represented by Formula III) are prepared using the synthetic scheme described in patent CN110446696A.

[0108] Examples 3-14

[0109] Examples 3-14 are all multi-thiol compositions, which are prepared by mixing the multi-thiol compound of Formula I prepared in Example 1 and the first multi-thiol composition prepared in Example 2 in different proportions, according to the mass of the multi-thiol compound of Formula I: the mass of the multi-thiol compound of Formula I and the mass of the first multi-thiol composition are equal to 0.001%, 0.01%, 0.02%, 0.04%, 0.06%, 0.08%, 0.1%, 0.5%, 1.0%, 2.0%, 5.0%, 8.0% of the total mass of the multi-thiol compound of Formula I and the first multi-thiol composition, to obtain Examples 3-14.

[0110] Application Examples 1-10

[0111] The multi-thiol compositions of Examples 3-12 are used to prepare optical materials, which specifically include the following steps:

[0112] (1) A kettle is charged with 20.0 parts by mass of xylylene diisocyanate, 0.01 parts by mass of an initiator (dibutyltin dichloride), and 0.08 parts by mass of a release agent (chloroalkyl polyphosphate), and the mixture is dissolved at 15°C with stirring at 200 rpm;

[0113] (2) 16.0 parts by mass of the multi-thiol composition of Examples 3-12 is added, respectively, and the mixture is stirred until uniform;

[0114] (3) The mixture is degassed using a vacuum pump, with the pressure controlled at 350 Pa, and the degassing time is 0.5 h, to prepare a mixed solution, which is poured into 20 pairs of clean glass molds with a diameter of 80 mm and a thickness of 10 mm, and the molds are placed flat on a tray after pouring is completed.

[0115] (4) The molds are placed in an oven for programmed temperature curing, and the programmed temperature curing is as follows: the temperature is kept at 30°C for 180 min, then increased to 45°C at a rate of 1.5°C / 10 min, then increased to 50°C at a rate of 0.50°C / 10 min, then increased to 60°C at a rate of 0.10°C / 10 min, then increased to 120°C at a rate of 3.0°C / 10 min, then kept at 120°C for 180 min, then decreased to 80°C at a rate of 4°C / 10 min, and the molds are removed and opened to obtain optical lenses.

[0116] Comparative Example 1

[0117] The method for preparing optical materials is basically the same as in Application Examples 1-10, except that in step (2), the multi-thiol composition of Examples 3-12 is not added, but the same mass of the first multi-thiol composition prepared in Example 2 is added.

[0118] Comparative Example 2

[0119] The method for preparing the optical material is substantially the same as that in application examples 1-10, except that the polythiol composition added in step (2) is the polythiol composition prepared in Example 13.

[0120] Comparative Example 3

[0121] The method for preparing the optical material is substantially the same as that in application examples 1-10, except that the polythiol composition added in step (2) is the polythiol composition prepared in Example 14.

[0122] Experimental Example 1

[0123] The haze, yellow index and refractive index of the optical lenses prepared in application examples 1-10 and comparative examples 1-3 were detected. The haze was detected using a TU5200 desktop haze meter; the yellow index was detected using an UltraScan PRO spectrophotometer; and the refractive index was detected according to QB / T2506. The detection results are shown in Table 1.

[0124] Table 1 Detection results of the refractive index and haze of the optical lenses in application examples 1-10 and comparative examples 1-3

[0125]

[0126] As can be seen from the above data, as the proportion of the mass of the polythiol compound in the sum of the mass of the polythiol compound and the first polythiol composition increases, the haze and yellow index of the optical lens decrease, and when the proportion of the polythiol compound is greater than 0.5%, the decreasing trend tends to be flat.

[0127] The results of comparative examples 2 and 3 show that although the haze and yellow index of the optical lens decrease slightly as the proportion of the polythiol compound further increases, the decreasing amplitude is small; and as the proportion of the polythiol compound increases, the refractive index is less than 1.646, which cannot meet the requirements for making optical lenses.

[0128] The above description of the disclosed embodiments enables one skilled in the art to make or use the present application. Numerous modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Therefore, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A polythiol compound, characterized by, The chemical structural formula is shown as formula I:

2. A method for preparing the polythiol compound of claim 1, characterized by, The method comprises the following steps: 1) adding an alkali solution dropwise to 2-mercaptoethanol, and stirring and reacting to obtain a first mixed solution; 2) adding bis(3-chloro-2-hydroxypropyl) sulfide dropwise to the first mixed solution obtained in step 1), and heating and reacting to obtain a first reaction solution, and the product is shown as formula A; 3) preparing a second mixed solution according to the same method and conditions as in step 1), wherein the same alkali solution as in step 1) is used, and the amount of 2-mercaptoethanol and the alkali solution used is the same as in step 1); 4) adding 1,3-dichloro-2-propanol dropwise to the second mixed solution obtained in step 3), and reacting to obtain a second reaction solution, wherein the reaction temperature and time are consistent with those in step 2), and the product is shown as formula B; 5) mixing the first reaction solution in step 2) and the second reaction solution in step 4), adding sodium sulfide, and stirring and reacting to obtain a third reaction solution, and the product is shown as formula C; 6) adding a hydrochloric acid solution and thiourea to the third reaction solution obtained in step 5), and refluxing to obtain a fourth reaction solution, and the product is shown as formula D; 7) adding an ammonia water solution to the fourth reaction solution obtained in step 6), and reacting at an elevated temperature to obtain a product containing a polysulfane compound shown as formula I.

3. The method of claim 2, wherein: In step 1), the molar ratio of 2-mercaptoethanol to the solute of the alkali solution is (1-2):(1-2); the temperature of the heat preservation is 50-70℃; the time of the heat preservation reaction is 0.5-1.5h; and the stirring speed is 200-400r / min; In step 2), the molar ratio of bis(3-chloro-2-hydroxypropyl) sulfide to 2-mercaptoethanol in step 1) is (0.3-0.7):(0.6-2); the reaction temperature is 60-80℃, and the reaction time is 1.5-4.5h; In step 4), the molar ratio of 1,3-dichloro-2-propanol to bis(3-chloro-2-hydroxypropyl) sulfide in step 2) is (0.8-1.2):(0.8-1.2); In step 5), the molar ratio of sodium sulfide to bis(3-chloro-2-hydroxypropyl) sulfide is (0.8-1.2):(0.8-1.2), the reaction temperature is 60-80℃, the reaction time is 1.5-4.5h, and the stirring speed is 200-400r / min; In step 6), the mass concentration of the hydrochloric acid is 20-38%, the molar ratio of the hydrochloric acid to sodium sulfide in step 5) is (1-5):(1-3), the molar ratio of the thiourea to sodium sulfide is (1-5):(1-3), the reflux reaction temperature is 110-120℃, and the time is 5-12h; In step 7), the mass concentration of the ammonia water is 10-20%, the molar ratio of ammonia in the ammonia water to sodium sulfide in step 5) is (3-12):(1-2), the reaction temperature is 90-100℃, and the time is 2-4h.

4. The production method according to claim 2, characterized by, The solvent of the alkali solution is water, and the solute is one or more of lithium hydroxide, sodium hydroxide, and potassium hydroxide, and the mass concentration of the alkali solution is 35-45%.

5. The production method according to claim 2, characterized by, After the step 7) is finished, the product is separated to obtain a crude product, and the crude product is washed with water and an acid solution, and then vacuum desolventized and purified by column chromatography to obtain the polysulfide compound shown in formula I; the water is distilled water, the amount of water used in each washing is the same as the mass of the crude product, and the number of washings is not less than 3 times; The acid solution is selected from one or more of an aqueous hydrochloric acid solution, an aqueous phosphoric acid solution, and an aqueous sulfuric acid solution, the mass fraction of the acid solution is 20-30%, the amount of acid solution used in each washing is 10% of the mass of the crude product, and the number of washings is not less than 2 times.

6. A polythiol composition comprising the polythiol compound of claim 1, wherein, The polysulfide composition comprises the polysulfide compound and a first polysulfide composition, the first polysulfide composition is a mixture of one or more of the compounds shown in formula II, formula III, and formula IV as the main component, the mass fraction of the polysulfide compound in the polysulfide composition is 0.001-2.00%, 7. A polymerizable composition comprising the polythiol composition of claim 6, wherein The polymeric composition comprises the polysulfide composition and an isocyanate compound, and the mass ratio of the polysulfide composition to the isocyanate compound in the polymeric composition is (0.7-1.1):

1.

8. The polymerizable composition of claim 7, wherein The isocyanate compound comprises one or more of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, lysine diisocyanate tetramethylene diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate, 4,4'-diisocyanate dicyclohexylmethane, isophorone diisocyanate, norbornane diisocyanate, and xylylene diisocyanate.

9. A method for producing an optical material using the polymerizable composition according to claim 8, characterized by, After the polymeric composition is mixed with an initiator, polymerization curing is performed to obtain an optical material; the initiator is selected from one of dimethyl tin dichloride, dibutyl tin dilaurate, dibutyl tin dichloride, and stannous octoate, and the amount of the initiator added is 0.005-0.05% of the total mass of the polymeric composition.

10. The method of claim 9, wherein the optical material is prepared by a method comprising: The specific steps are as follows: A) The isocyanate compound and the initiator are stirred and dissolved to obtain a first mixed solution; B) The first mixed solution and the polysulfide composition are mixed and degassed to obtain a second mixed solution; C) The second mixed solution is poured into a mold for polymerization curing to obtain an optical material; In step A), the stirring and dissolving temperature is 10-20°C, and the stirring speed is 200-400 r / min; In step A), a release agent is added, and the mass ratio of the release agent to the isocyanate compound is (0.002-0.006):100, and the release agent is selected from one of alkyl polyphosphates and chloroalkyl polyphosphates; In step B), a vacuum pump is used for degassing, the pressure is controlled to be below 350 Pa, and the degassing time is 0.5-1.0 h; In step C), after pouring, the mold is placed flat on a tray for temperature curing, the mold is a glass mold with a curved surface of 0°, a diameter of 80 mm, and a thickness of 10 mm; the polymerization curing temperature is 100-125°C, and the polymerization curing time is 2-4 h.

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