阅读说明：本技术 一种聚硫醚的制备方法 (Preparation method of polythioether ) 是由 尤庆亮 谢光勇 陈昊 熊新阳 肖标 邹立勇 高淑豫 刘志宏 刘继延 刘学清 于 2019-01-23 设计创作，主要内容包括：本发明提供了一种聚硫醚的制备方法,步骤包括：以小分子炔烃或二烯烃或烯炔中的一种、硫化氢或二元或多元硫醇中的一种为原料,添加引发剂或催化剂,在高压或常压下聚合得到主链规整的聚硫醚,所述聚硫醚仅含有一种重复单元,所述重复单元含有硫醚键,所述聚硫醚的主链上无支链或仅连接有短支链或苯基。本发明采用工业常用化工原料,制备得到规整度极高的聚硫醚,产品收率达96％以上,且产品封端基团可控,能够通过采用超临界CO<Sub>2</Sub>体系省去溶剂去除工艺,且避免了反应体系中水的引入,使该反应在无水聚硫醚制备中具有巨大优势,因此本发明具备良好的工业应用前景。(The invention provides a preparation method of polythioether, which comprises the following steps: taking small-molecular alkyne, diene or one of enynes, hydrogen sulfide or one of binary or polybasic mercaptan as a raw material, adding an initiator or a catalyst, and polymerizing under high pressure or normal pressure to obtain polythioether with a regular main chain, wherein the polythioether only contains one repeating unit, the repeating unit contains thioether bonds, and the main chain of the polythioether is not branched or is only connected with a short branch or phenyl. The polythioether with extremely high regularity is prepared by adopting industrial common chemical raw materials, the product yield is more than 96%, the end-capping group of the product is controllable, and the polythioether can be prepared by adopting supercritical CO 2 The system omits a solvent removal process, avoids the introduction of water in the reaction system, and has great advantages in the preparation of anhydrous polythioether, so the method has good industrial application prospect.)

1. A method for preparing a polythioether, comprising the steps of: taking small-molecular alkyne, diene or one of enynes, hydrogen sulfide or one of binary or polybasic mercaptan as a raw material, adding an initiator or a catalyst, and polymerizing under high pressure to obtain polythioether with a regular main chain, wherein the polythioether only contains one repeating unit, the repeating unit contains thioether bonds, and the main chain of the polythioether is not branched or is connected with a short branch or a phenyl; the initiation systems fall into two categories: the first type of initiator is a free radical photoinitiator, a free radical thermal initiator or a composite initiation system; the second catalyst is inorganic base, organic base or organic amine.

2. The method of claim 1, wherein the polythioether is prepared by: the high pressure is 1-11MPa, the reaction temperature is 10-320 ℃, and the optimal reaction temperature is 20-150 ℃.

3. The method of claim 2, wherein the polythioether is prepared by: dissolving an initiator in a solvent, introducing one of micromolecular alkyne, diene or enyne into a reaction container under a high pressure condition to enable the solvent to absorb and saturate, introducing one of hydrogen sulfide and binary or polybasic mercaptan under a stirring condition, initiating the reaction under the condition of 1-3 Mpa of air pressure and ultraviolet light, and reacting at 20-30 ℃ to obtain polythioether; the solvent is a mixture of an organic solvent which is easy to dissolve in water and water, and the organic solvent comprises one or two of acetone or butanone.

4. The method of claim 2, wherein the polythioether is prepared by: dissolving a catalyst in a solvent, introducing one of micromolecular alkyne, diene or enyne into a reaction container under a high pressure condition to enable the solvent to absorb and saturate, introducing one of hydrogen sulfide and binary or polybasic mercaptan under a stirring condition, and reacting under the pressure of 1-3 MPa and the temperature of 45-55 ℃ to obtain polythioether; the solvent is a mixture of an organic solvent which is easily soluble in water and water, and the organic solvent comprises acetone.

5. The method of claim 2, wherein the polythioether is prepared by: adding an initiator or a catalyst into a reaction vessel, and taking one of acetylene and small molecular derivatives thereof or diene and one of hydrogen sulfide or dithiol or polythiol as raw materials in supercritical CO₂The polythioether is obtained by the reaction under the following conditions: the pressure is 8-11 Mpa, and the temperature is 20-30 ℃.

6. The method of claim 5, wherein the polythioether is prepared by: adding initiator or catalyst, sulfide salt and water into a reaction vessel, introducing acetylene, and reacting in supercritical CO₂The polythioether is obtained by the reaction; or a sulfide salt with H₂Reaction of O with carbon dioxide to produce H₂S is CO₂Introducing carrier gas into a reaction vessel containing initiator or catalyst and acetylene, and treating with supercritical CO₂The polythioether is obtained by the reaction of (1).

7. A method of preparing a polythioether according to any one of claims 1-3, wherein: the small molecule alkyne is one of acetylene, propine, butyne, pentyne, phenylacetylene and phenylpropyne; the eneyne is vinyl acetylene; the diene is butadiene, isoprene, One of (1); wherein the content of the first and second substances,

R₁＝Ph，-(CH₂)_n’-or-CH (C)_mH_2m+1)-(CH₂)_n-；n’＝1-100，m＝1-10，n＝1-1000。

8. The method of claim 7, wherein the polythioether is prepared by: the polythioether comprises the structure:

wherein:

R₁＝Ph，-(CH₂)_n’-or-CH (C)_mH_2m+1)-(CH₂)_n-；n’＝1-100，m＝1-10，n＝1-1000；

R₂＝-H、-CH₃、-C₂H₅、-C₃H₇、-Ph。

9. The method of claim 1, wherein the polythioether is prepared by: the free radical photoinitiator is one or more of Irgacure1173, Irgacure-184, Irgacure-2959, Irgacure-651, Irgacure-369, Irgacure-907, Irgacure-1300, Irgacure-784, Irgacure-250, Irgacure-819DW, Darocur-4265, Darocur BP, Darocur MBF, Darocur TPO and Darocur-1173Several kinds of the raw materials; the free radical thermal initiator is one or two of BPO and AIBN; the composite initiation system is H₂O₂With Fe²⁺A composite initiation system; the inorganic base comprises NaOH or KOH; the organic base comprises sodium ethoxide or potassium ethoxide; the organic amine comprises one or more of diethylamine, triethylamine, ethanolamine, diethanolamine and triethanolamine.

10. The method of claim 9, wherein the polythioether is prepared by: the addition proportion of the photoinitiator is 0.01-10% of the total mass of the raw materials in percentage by mass.

Technical Field

The invention belongs to the technical field of preparation of high polymer materials, and particularly relates to a preparation method of polythioether.

Background

Acetylene is a large chemical raw material, is called as a mother material of PVC (polyvinyl chloride) industry together with chlor-alkali industry, but the PVC industry in China at present becomes the first major PVC producing country in the world after multiple rounds of large-scale disordered expansion, so that the capacity is seriously excessive, the disordered low-level repeated construction of PVC products is caused, and the additional value of the PVC industry is reduced year by year. Another important use of acetylene is in the preparation of fluoromonomers and in the preparation of fluoropolymers. Therefore, the research and development of high-level dissimilatory acetylene derived products become important power for the upgrading, updating and further development of the industry.

One of the most important academic advances of acetylene in the last 20 years is that "elemental iodine initiates polyacetylene to generate the first conducting polymer", and therefore, the white-english and black-guel also obtain the nobel prize all at once, but the application of the material is always in the laboratory research stage for many years, and does not bring substantial application to acetylene or PVC industry.

The invention aims to prepare a series of functional monomers and polymers by adopting acetylene, and simultaneously provide polythioether monomers, prepolymers and polymers for large-scale application.

The reaction of alkyne and thiol is known as a novel click chemistry reaction, and is applied to modification and grafting of various macromolecular polymers with high conversion rate and high selectivity. However, there are few patents on the synthesis of prepolymers and polymers from small molecules of acetylene and mercaptan. The invention develops a series of special monomers, prepolymers and polymers which have special characteristics and are used for preparing polythioethers.

Disclosure of Invention

In view of the above, the main objective of the present invention is to provide a method for preparing polythioether, which can synthesize polythioether with regular main chain by using industrial common raw materials, namely small molecular acetylene and hydrogen sulfide, and binary or polyhydric mercaptan, as reaction raw materials, and has good industrial application prospects.

The invention provides a preparation method of polythioether, which comprises the following steps: taking small-molecular alkyne, diene or one of enynes, hydrogen sulfide or one of binary or polybasic mercaptan as a raw material, adding an initiator or a catalyst, and polymerizing under high pressure to obtain polythioether with a regular main chain, wherein the polythioether only contains one repeating unit, the repeating unit contains thioether bonds, and the main chain of the polythioether is not branched or is only connected with short-chain branches or phenyl; the initiator is a free radical photoinitiator, a free radical thermal initiator or a composite initiation system; the catalyst is inorganic base, organic base or organic amine.

Preferably, the high pressure is 1-11MPa, the high pressure is 10-320 ℃, and the optimal reaction temperature is 20-150 ℃.

More preferably, the method can use a mixture of an organic solvent and water as a reaction solvent, and adds an initiator and raw materials to carry out reaction, and comprises the following steps: dissolving an initiator in a solvent, introducing one of micromolecular alkyne, diene or enyne into a reaction container under a high pressure condition to enable the solvent to absorb and saturate, introducing one of hydrogen sulfide or binary or polybasic mercaptan under a stirring condition, initiating the reaction under the condition of 1-3 Mpa of air pressure and ultraviolet light, and reacting at 20-30 ℃ to obtain polythioether; the solvent is a mixture of an organic solvent which is easy to dissolve in water and water, and the organic solvent comprises one or two of acetone or butanone.

More preferably, the Michael addition reaction can also be carried out very effectively and independently by using a catalyst, and the method takes a mixture of an organic solvent and water as a reaction solvent, and adds the catalyst and raw materials for reaction, and comprises the following steps: dissolving a catalyst in a solvent, introducing one of micromolecular alkyne, diene or enyne into a reaction container under a high pressure condition to enable the solvent to absorb and saturate, introducing one of hydrogen sulfide or binary or polybasic mercaptan under a stirring condition, and reacting under the pressure of 1-3 MPa and the temperature of 45-55 ℃ to obtain polythioether; the solvent is a mixture of an organic solvent which is easily soluble in water and water, and the organic solvent comprises acetone.

Specifically, in the reaction, flexible conversion of the polythioether end-capping group can be realized by adjusting the ratio of the small-molecule alkyne to the thiol, so that the polythioether end-capping group is controllable, and regular polythioethers capped by different groups can be obtained according to actual needs.

In several examples of the present invention, the above reaction process is described in detail using acetylene and hydrogen sulfide as raw materials and a mixture of an organic solvent and water as a reaction solvent. And by adjusting the reaction ratio of acetylene and hydrogen sulfide, the mercapto-terminated regular polythioether and the vinyl-terminated regular polythioether are respectively obtained, and the high molecular weight regular polythioether is further obtained. Based on similar reaction principles, the reaction raw materials of the invention are not limited to acetylene and hydrogen sulfide, for example, in another embodiment of the invention, the reaction is carried out by taking phenylacetylene and hydrogen sulfide as raw materials, and different group-terminated regular polythioethers can be successfully obtained by adjusting the reaction ratio of the raw materials.

More preferably, based on supercritical CO₂Good compatibility to reaction raw materials, the invention further realizes CO₂The polymerization reaction of the supercritical system omits the fussy process of solvent removal, avoids the introduction of water in the reaction system, and comprises the following reaction steps: adding an initiator or a catalyst into a reaction vessel, and taking one of acetylene and small molecular derivatives thereof or diene and one of hydrogen sulfide or dithiol or polythiol as raw materials in supercritical CO₂The polythioether is obtained by the reaction under the following conditions: the pressure is 8-11 Mpa, and the temperature is 20-30 ℃. In several embodiments of the invention, acetylene and H are used₂S is used as raw material in supercritical CO₂The polythioether is obtained by the reaction of (1). The reaction can be made easier because the boiling point of the substituent acetylene and diene is higher when the acetylene is converted to the substituent acetylene or diene; when H is present₂When S is converted into a di-or polyfunctional thiolCritical CO₂Has better compatibility and is beneficial to the reaction, so the supercritical CO is adopted₂The raw materials used in the reaction of the system are not limited to acetylene and H₂And S.

Further preferred, the invention uses as H a sulphide salt that is convenient to store and transport₂S source applied to the supercritical CO₂In the reaction system, the regular polythioether is successfully obtained. Further expands the source of mercaptan raw material and effectively avoids H₂S difficult storage and transportation, strengthened CO₂The advantages of the supercritical method preparation expand the application range and the application field of the invention. The reaction steps comprise: adding initiator or catalyst, sulfide salt and water into a reaction vessel, introducing acetylene, and reacting in supercritical CO₂The polythioether is obtained by the reaction; or a sulfide salt with H₂Reaction of O with carbon dioxide to produce H₂S is CO₂Introducing carrier gas into a reaction vessel containing initiator or catalyst and acetylene, and treating with supercritical CO₂The polythioether is obtained by the reaction of (1). The sulfide salt may be Na₂S or GaS, Li₂S and the like.

Preferably, in the above reaction, N may be introduced after the polymerization reaction is completed₂The residual acetylene and hydrogen sulfide gas are replaced for reaction end point detection, and 1% lead acetate aqueous solution is used for detecting whether H exists₂S, residual; and (3) testing whether acetylene residue exists or not by using a 2-5% cuprous ammonia solution. If the residue exists, the reaction is continued for a period of time, and then the reaction is detected again until the end point of the reaction.

More preferably, N is introduced after the end of the reaction is reached₂Displacing residual acetylene and hydrogen sulfide gas, and respectively introducing the exhaust gas into NaOH aqueous solution to absorb H₂And S, introducing acetone to absorb acetylene, thereby realizing the recycling of hydrogen sulfide and acetylene gas.

Preferably, based on similar reaction principles, the reaction raw materials of the present invention are not limited to the ones listed in the examples, and in the above preparation method, the small molecule alkyne can be one of acetylene, propyne, butyne, pentyne, phenylacetylene and phenylpropyne; said enyne isVinyl acetylene; the diene can be butadiene, isoprene,One of (1); wherein the content of the first and second substances,

R₁＝Ph，-(CH₂)_n’-or-CH (C)_mH_2m+1)-(CH₂)_n-；n’＝1-100，m＝1-10，n＝1-1000。

Hydrogen sulfide and mono-, di-, tri-and polythiols are suitable for the above reactions to prepare monomers, prepolymers and polymers.

More preferably, the polythioether comprises the structure:

wherein: r and R1 are the same as previously described; r₂＝-H、-CH₃、-C₂H₅、-C₃H₇、-Ph。

Specifically, the above-listed reaction raw materials relate to the following reaction formula:

preferably, in the above reaction, the radical photoinitiator is one of Irgacure1173, Irgacure-184, Irgacure-2959, Irgacure-651, Irgacure-369, Irgacure-907, Irgacure-1300, Irgacure-784, Irgacure-250, Irgacure-819DW, Darocur-4265, Darocur BP, Darocur MBF, Darocur TPO, Darocur-1173One or more of (a); the free radical thermal initiator is one or two of BPO and AIBN; the composite initiation system is H₂O₂With Fe²⁺A composite initiation system; the inorganic base comprises NaOH or KOH; the organic base comprises sodium ethoxide or potassium ethoxide; the organic amine comprises one or more of diethylamine, triethylamine, ethanolamine, diethanolamine and triethanolamine.

More preferably, the addition ratio of the photoinitiator is 0.01-10% of the total mass of the raw materials in percentage by mass.

More preferably, the addition ratio of the photoinitiator is 0.1-0.5% of the total mass of the raw materials in percentage by mass.

Compared with the prior art, the invention has the beneficial effects that:

(1) the method can take industrial common chemical raw materials of small molecular acetylene and hydrogen sulfide as reaction raw materials, the raw materials are wide in source, easy to obtain and common in use, the reaction process is simple and easy to control, the regularity of the main chain of the prepared polythioether is extremely high, the product yield reaches more than 96%, and the method has good industrial application prospect.

(2) The invention can realize the flexible transformation of the polythioether end-capping group by adjusting the adding proportion of the raw materials, so that the polythioether end-capping group is controllable, and the application range and the application field of the invention are enlarged.

(3) The invention can not only adopt a common autoclave to carry out polymerization reaction, but also can carry out supercritical CO₂The system initiates polymerization, omits a complicated process of solvent removal to directly obtain a polymer, avoids the introduction of water in a reaction system, greatly reduces the micro content of water, and has great advantages in the preparation of anhydrous polythioether.

(4) The invention can use sulfide salt as H which is convenient for storage and transportation₂S source to supercritical CO₂In the reaction system, the source of mercaptan raw materials is enlarged, and H is effectively avoided₂S difficult storage and transportation, strengthened CO₂The advantages of the supercritical method for preparation expand the application range and the application field of the invention, and the reaction is more beneficial to the industrial implementation.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the following specific examples.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.