Low-end-group chlorine polyphenylene sulfide and preparation method thereof

Abstract

The invention discloses low-end-group chlorine polyphenylene sulfide and a preparation method thereof.The preparation method comprises the following steps that N-methyl pyrrolidone, a sodium hydrosulfide aqueous solution, a hydroxide aqueous solution and a catalyst are mixed, and a mixture is obtained; removing free water in the mixture, adding N-methyl pyrrolidone and p-dichlorobenzene into the mixture under a nitrogen protection atmosphere, heating to 180-240 DEG C, carrying out an early polymerization reaction, heating to 240-270 DEG C, adding a third monomer, and carrying out a later polymerization reaction; and after the reaction is finished, cooling, filtering, washing and drying to obtain the low-end-group chlorine polyphenylene sulfide. Through an innovative synthesis process, the prepared PPS resin with low end group chlorine is uniform in particle shape, the product yield is in an industry leading level, and the problems that in a traditional process, the content of end group chlorine of a product is high, and the product gradually dissociates in the processing process are effectively solved; by means of excellent performance, the packaging film can be widely applied to high-end fields such as electronic component packaging and the like.

Description

Technical Field

[0001] This invention relates to the field of polyphenylene sulfide technology, specifically to a low-end chlorinated polyphenylene sulfide and its preparation method. Background Technology

[0002] The residual chloride ions in polyphenylene sulfide (PPS) mainly fall into two categories: one is the residual sodium chloride, a byproduct generated during PPS synthesis, known as free chlorine; the other is the terminal chloride produced during the dichlorobenzene reaction. Currently, through multiple washing and particle size control, the overall chlorine content can be reduced from 2500 ppm to below 900 ppm, with the terminal chloride content being approximately between 500-800 ppm.

[0003] Under high-temperature machining and usage conditions, terminal chlorine gradually transforms into free chlorine; and during prolonged use, it gradually migrates into the internal components of electrical appliances, damaging their efficiency and reducing their lifespan. High-precision electronic products require chlorine content below 200 ppm, a requirement that current conventional products cannot meet. Therefore, a polyphenylene sulfide with low terminal chlorine content was developed to address this need. Summary of the Invention

[0004] The purpose of this invention is to provide a low-terminal chlorine polyphenylene sulfide and its preparation method. The polyphenylene sulfide prepared by the method of this invention has a low terminal chlorine content, which solves the current application problem of polyphenylene sulfide in the field of high-precision electronic appliances.

[0005] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0006] The first aspect of this invention provides a method for preparing low-terminated polyvinyl chloride sulfide, the method comprising the following steps:

[0007] (a) N-methylpyrrolidone, aqueous sodium hydrosulfide solution, aqueous hydroxide solution and catalyst are mixed to obtain a mixture;

[0008] (b) Remove free water from the mixture, add N-methylpyrrolidone and p-dichlorobenzene to the mixture under a nitrogen protective atmosphere and heat to 180~240°C for the early polymerization reaction, then raise the temperature to 240~270°C and add a third monomer for the late polymerization reaction;

[0009] (c) After the reaction is complete, the mixture is cooled, filtered, washed and dried to obtain the low-end polyvinyl chloride sulfide.

[0010] Preferably, in step (a), the mass ratio of N-methylpyrrolidone, sodium hydrosulfide aqueous solution, hydroxide aqueous solution and catalyst is (10~14):(6~8):(7~9):(1.5~2.5).

[0011] Preferably, in step (a), the catalyst is at least one of sodium acetate, sodium phosphate, lithium chloride, and sodium carbonate.

[0012] Preferably, in step (a), the concentration of the sodium hydrosulfide aqueous solution is 45%~50%; and the concentration of the sodium hydroxide aqueous solution is 28%~34%.

[0013] Preferably, in step (b), the amount of N-methylpyrrolidone added is 1.5 to 1.9 times that in step (a); the mass ratio of the amount of p-dichlorobenzene added to the sodium hydrosulfide solution is (8 to 10): (6 to 8).

[0014] Preferably, in step (b), the initial polymerization reaction time is 1-3 hours.

[0015] Preferably, in step (b), the later polymerization reaction time is 2-4 hours.

[0016] Preferably, in step (b), the third monomer is selected from at least one of 1-chlorobenzene, 1-chloronaphthalene, 2-chloronaphthalene, 1-chlorohexane, 1-chloroheptane, 1-chlorooctane, 1-chlorononane, 1-chlorodecane, 1-chloroundecane, 1-chlorododecane, 1-chlorotridecane, 1-chlorotetradecane, 1-chlorohexadecane, o-chlorotoluene, m-chlorotoluene, p-chlorotoluene, p-chlorostyrene, p-chlorobenzoic acid, sodium p-chlorobenzoate, p-chloromethylstyrene, chlorocyclohexane, 2-chloroethanol, allyl chloroacetate, and 1-chloro-2-butene;

[0017] The amount of the third monomer added is 1‰ to 2‰ of the mass of dichlorobenzene.

[0018] Preferably, in step (c), the washing includes washing with a variety of solvents; the solvents include NMP, water, MPC, dichloromethane, chloroform, ethyl acetate, phenol, acetone and isobutanol.

[0019] A second aspect of the present invention provides a low-end polyvinyl chloride sulfide prepared by the above preparation method.

[0020] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0021] This invention utilizes an innovative synthesis process to produce PPS resin particles with uniform morphology and industry-leading yields with low-terminal chloride content. This effectively solves the problem of high end-terminal chloride content and gradual release during processing, a common issue in traditional processes. Due to its superior performance, it can be widely applied in high-end fields such as electronic component packaging. Furthermore, the end-capping agent used in this invention is chemically stable and has relaxed requirements for production conditions. No special equipment or complex processes are needed; with only minor process adjustments and without altering the main structure of existing PPS resin production lines, the preparation of low-terminal chloride PPS resin can be achieved on existing PPS production lines, significantly reducing the cost of technological upgrades. Detailed Implementation

[0022] The embodiments of the technical solution of the present invention will be described in detail below with reference to the examples. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and are therefore only examples, and should not be used to limit the scope of protection of the present invention.

[0023] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0024] This invention provides a method for preparing low-terminated polyvinyl chloride sulfide, the method comprising the following steps:

[0025] (a) N-methylpyrrolidone, aqueous sodium hydrosulfide solution, aqueous hydroxide solution and catalyst are mixed to obtain a mixture;

[0026] (b) Remove free water from the mixture, add N-methylpyrrolidone and p-dichlorobenzene to the mixture under a nitrogen protective atmosphere and heat to 180~240°C for the early polymerization reaction, then raise the temperature to 240~270°C and add a third monomer for the late polymerization reaction;

[0027] (c) After the reaction is complete, the mixture is cooled, filtered, washed and dried to obtain the low-end polyvinyl chloride sulfide.

[0028] This invention utilizes an innovative synthesis process to produce PPS resin particles with uniform morphology and industry-leading yields with low-terminal chloride content. This effectively solves the problem of high end-terminal chloride content and gradual release during processing, a common issue in traditional processes. Due to its superior performance, it can be widely applied in high-end fields such as electronic component packaging. Furthermore, the end-capping agent used in this invention is chemically stable and has relaxed requirements for production conditions. No special equipment or complex processes are needed; with only minor process adjustments and without altering the main structure of existing PPS resin production lines, the preparation of low-terminal chloride PPS resin can be achieved on existing PPS production lines, significantly reducing the cost of technological upgrades.

[0029] In one embodiment, in step (a), the mass ratio of N-methylpyrrolidone, sodium hydrosulfide aqueous solution, aqueous hydroxide solution and catalyst is (10~14):(6~8):(7~9):(1.5~2.5).

[0030] In one embodiment, in step (a), the catalyst is at least one of sodium acetate, sodium phosphate, lithium chloride, and sodium carbonate.

[0031] In one embodiment, in step (a), the concentration of the sodium hydrosulfide aqueous solution is 45%~50%; the concentration of the sodium hydroxide aqueous solution is 28%~34%.

[0032] In one embodiment, in step (b), the amount of N-methylpyrrolidone added is 1.5 to 1.9 times that in step (a); the mass ratio of the amount of p-dichlorobenzene added to the sodium hydrosulfide solution is (8 to 10): (6 to 8).

[0033] In one embodiment, in step (b), the initial polymerization reaction time is 1 to 3 hours.

[0034] In one embodiment, in step (b), the late-stage polymerization reaction time is 2-4 hours.

[0035] In one embodiment, in step (b), the third monomer is selected from at least one of 1-chlorobenzene, 1-chloronaphthalene, 2-chloronaphthalene, 1-chlorohexane, 1-chloroheptane, 1-chlorooctane, 1-chlorononane, 1-chlorodecane, 1-chloroundecane, 1-chlorododecane, 1-chlorotridecane, 1-chlorotetradecane, 1-chlorohexadecane, o-chlorotoluene, m-chlorotoluene, p-chlorotoluene, p-chlorostyrene, p-chlorobenzoic acid, sodium p-chlorobenzoate, p-chloromethylstyrene, chlorocyclohexane, 2-chloroethanol, allyl chloroacetate, and 1-chloro-2-butene;

[0036] The amount of the third monomer added is 1‰ to 2‰ of the mass of dichlorobenzene.

[0037] In one embodiment, step (c) includes washing with various solvents, including NMP, water, MPC, dichloromethane, chloroform, ethyl acetate, phenol, acetone, and isobutanol.

[0038] Another embodiment of the present invention provides a low-end polyvinyl chloride sulfide prepared by the above preparation method.

[0039] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0040] Example 1

[0041] This embodiment describes a method for preparing low-terminated polyvinyl chloride sulfide, which includes the following steps:

[0042] (a) Add 12 kg of N-methylpyrrolidone, 7.15 kg of sodium hydrosulfide aqueous solution (content 47%), 8.13 kg of hydroxide aqueous solution (31%) and 1.96 kg of catalyst (sodium carbonate) to a 60 L reactor and mix to obtain a mixture;

[0043] (b) Remove free water from the mixture, add 20 kg of N-methylpyrrolidone and 8.82 kg of p-dichlorobenzene to the mixture under a nitrogen protective atmosphere, heat to 210 °C for a preliminary polymerization reaction for 2 h, then raise the temperature to 250 °C and add 10 g of 1-chlorobenzene for a later polymerization reaction for 3 h.

[0044] (c) After the reaction is complete, the mixture is cooled, filtered, washed with MPC, dichloromethane and water respectively, and dried to obtain the low-end polyvinyl chloride sulfide.

[0045] Example 2

[0046] This embodiment describes a method for preparing low-terminated polyvinyl chloride sulfide, which includes the following steps:

[0047] (a) Add 12 kg of N-methylpyrrolidone, 7.15 kg of sodium hydrosulfide aqueous solution (content 47%), 8.13 kg of hydroxide aqueous solution (31%) and 1.96 kg of catalyst (sodium carbonate) to a 60 L reactor and mix to obtain a mixture;

[0048] (b) Remove free water from the mixture, add 20 kg of N-methylpyrrolidone and 8.82 kg of p-dichlorobenzene to the mixture under a nitrogen protective atmosphere, heat to 180°C for a preliminary polymerization reaction for 3 h, then raise the temperature to 240°C and add 15 g of 1-chlorobenzene for a later polymerization reaction for 4 h.

[0049] (c) After the reaction is complete, the mixture is cooled, filtered, washed with MPC, dichloromethane and water respectively, and dried to obtain the low-end polyvinyl chloride sulfide.

[0050] Example 3

[0051] This embodiment describes a method for preparing low-terminated polyvinyl chloride sulfide, which includes the following steps:

[0052] (a) Add 12 kg of N-methylpyrrolidone, 7.15 kg of sodium hydrosulfide aqueous solution (content 47%), 8.13 kg of hydroxide aqueous solution (31%) and 1.96 kg of catalyst (sodium carbonate) to a 60 L reactor and mix to obtain a mixture;

[0053] (b) Remove free water from the mixture, add 20 kg of N-methylpyrrolidone and 8.82 kg of p-dichlorobenzene to the mixture under a nitrogen protective atmosphere, heat to 240 °C for a preliminary polymerization reaction for 1 h, then raise the temperature to 270 °C and add 10 g of 1-chlorobenzene for a later polymerization reaction for 2 h.

[0054] (c) After the reaction is complete, the mixture is cooled, filtered, washed with MPC, dichloromethane and water respectively, and dried to obtain the low-end polyvinyl chloride sulfide.

[0055] Comparative Example 1

[0056] This comparative example illustrates a method for preparing low-terminated polyvinyl chloride sulfide, the method comprising the following steps:

[0057] (a) Add 12 kg of N-methylpyrrolidone, 7.15 kg of sodium hydrosulfide aqueous solution (content 47%), 8.13 kg of hydroxide aqueous solution (31%) and 1.96 kg of catalyst (sodium carbonate) to a 60 L reactor and mix to obtain a mixture;

[0058] (b) Remove free water from the mixture, add 20 kg of N-methylpyrrolidone and 8.82 kg of p-dichlorobenzene to the mixture under a nitrogen protective atmosphere, and heat to 210 °C for a preliminary polymerization reaction for 2 h, and then raise the temperature to 250 °C for a later polymerization reaction for 3 h.

[0059] (c) After the reaction is complete, the mixture is cooled, filtered, washed with MPC, dichloromethane and water respectively, and dried to obtain the low-end polyvinyl chloride sulfide.

[0060] Comparative Example 2

[0061] This comparative example illustrates a method for preparing low-terminated polyvinyl chloride sulfide, the method comprising the following steps:

[0062] (a) Add 12 kg of N-methylpyrrolidone, 7.15 kg of sodium hydrosulfide aqueous solution (content 47%), 8.13 kg of hydroxide aqueous solution (31%) and 1.96 kg of catalyst (sodium carbonate) to a 60 L reactor and mix to obtain a mixture;

[0063] (b) Remove free water from the mixture, add 20 kg of N-methylpyrrolidone and 8.82 kg of p-dichlorobenzene to the mixture under a nitrogen protective atmosphere, heat to 250 °C for a preliminary polymerization reaction for 2 h, then raise the temperature to 250 °C and add 10 g of 1-chlorobenzene for a later polymerization reaction for 3 h.

[0064] (c) After the reaction is complete, the mixture is cooled, filtered, washed with MPC, dichloromethane and water respectively, and dried to obtain the low-end polyvinyl chloride sulfide.

[0065] Experimental Example

[0066] Low-end chlorinated polyphenylene sulfides were prepared according to the preparation methods of Examples 1-3 and Comparative Examples 1-2, respectively.

[0067] The end-chlorine content of the above-mentioned low-terminated chlorinated polyphenylene sulfide was detected by oxygen bomb combustion + ion chromatography. The detection results are shown in Table 1.

[0068] Table 1

[0069] Group Terminal chlorine content Example 1 154ppm Example 2 128 ppm Example 3 144ppm Comparative Example 1 1447ppm Comparative Example 2 400ppm

[0070] As shown in Table 1:

[0071] Compared with the comparative example, the low-terminal chlorine polyphenylene sulfide prepared by the technical solution of this application has a lower end-terminal chlorine content.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for preparing low-terminated polyvinyl chloride sulfide, characterized in that, The preparation method includes the following steps: (a) N-methylpyrrolidone, aqueous sodium hydrosulfide solution, aqueous hydroxide solution and catalyst are mixed to obtain a mixture; (b) Remove free water from the mixture, add N-methylpyrrolidone and p-dichlorobenzene to the mixture under a nitrogen protective atmosphere and heat to 180~240°C for the early polymerization reaction, then raise the temperature to 240~270°C and add a third monomer for the late polymerization reaction; (c) After the reaction is complete, the mixture is cooled, filtered, washed and dried to obtain the low-end polyvinyl chloride sulfide.

2. The preparation method according to claim 1, characterized in that, In step (a), the mass ratio of N-methylpyrrolidone, sodium hydrosulfide aqueous solution, hydroxide aqueous solution and catalyst is (10~14):(6~8):(7~9):(1.5~2.5).

3. The preparation method according to claim 1, characterized in that, In step (a), the catalyst is at least one of sodium acetate, sodium phosphate, lithium chloride, and sodium carbonate.

4. The preparation method according to claim 1, characterized in that, In step (a), the concentration of the sodium hydrosulfide aqueous solution is 45%~50%; the concentration of the sodium hydroxide aqueous solution is 28%~34%.

5. The preparation method according to claim 1, characterized in that, In step (b), the amount of N-methylpyrrolidone added is 1.5 to 1.9 times that in step (a); the mass ratio of the amount of p-dichlorobenzene added to the sodium hydrosulfide solution is (8 to 10): (6 to 8).

6. The preparation method according to claim 1, characterized in that, In step (b), the initial polymerization reaction time is 1-3 hours.

7. The preparation method according to claim 1, characterized in that, In step (b), the later polymerization reaction time is 2-4 hours.

8. The preparation method according to claim 1, characterized in that, In step (b), the third monomer is selected from at least one of 1-chlorobenzene, 1-chloronaphthalene, 2-chloronaphthalene, 1-chlorohexane, 1-chloroheptane, 1-chlorooctane, 1-chlorononane, 1-chlorodecane, 1-chloroundecane, 1-chlorododecane, 1-chlorotridecane, 1-chlorotetradecane, 1-chlorohexadecane, o-chlorotoluene, m-chlorotoluene, p-chlorotoluene, p-chlorostyrene, p-chlorobenzoic acid, sodium p-chlorobenzoate, p-chloromethylstyrene, chlorocyclohexane, 2-chloroethanol, allyl chloroacetate, 1-chloro-2-butene, catechol monomethyl ether, catechol monomethyl ether, resorcinol monomethyl ether, 4,4'-dihydroxydiphenyl sulfone, bisphenol S, bisphenol A, 5-chloro-2-hydroxybenzoic acid, p-tert-butylphenol, cinnamylphenol, methyl salicylate, nonylphenol, p-(α-cumyl)phenol, and 2-naphthol. The amount of the third monomer added is 1‰ to 2‰ of the mass of dichlorobenzene.

9. The preparation method according to claim 1, characterized in that, In step (c), the washing process includes washing with various solvents; the solvents include NMP, water, MPC, dichloromethane, chloroform, ethyl acetate, phenol, acetone, and isobutanol.

10. Low-terminal polyvinyl chloride sulfide prepared by any of the preparation methods described in claims 1 to 9.