Aromatic sulfone polymer and its preparation method and application

Abstract

The invention discloses an aromatic sulfone polymer, the main chain of which contains fluoromethyl side groups. The aromatic sulfone polymer comprises structural units derived from fluoromethyl-containing bisphenol monomers, structural units derived from bisphenol monomers and structural units derived from sulfone monomers, and the fluoromethyl side groups in the aromatic sulfone polymer account for 0.5-5 mol% of the total of the structural units derived from the fluoromethyl-containing bisphenol monomers, the structural units derived from bisphenol monomers and the structural units derived from sulfone monomers. The invention introduces a certain proportion of fluoromethyl side groups into the main chain of the aromatic sulfone polymer, reduces the polarity of the resin to a certain extent, reduces the interaction between chemical reagents and the aromatic sulfone polymer, thereby effectively improving the chemical resistance of the aromatic sulfone polymer (especially the tolerance to ketone reagents), while maintaining excellent mechanical properties.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to an aromatic sulfone polymer and a preparation method and application thereof. Background Art

[0002] Aromatic sulfone polymers are high temperature resistant transparent thermoplastic engineering plastics with outstanding thermal properties, excellent chemical resistance, outstanding high temperature creep resistance, excellent dimensional stability, extremely low smoke and toxic gas emissions, as well as superior resistance to hot water, superheated steam and good electrical properties. With the increasing perfection of the development of aromatic sulfone polymer materials, its application range is becoming wider and wider, and it is applicable in aerospace, medical and health, food, household appliances, electronic appliances, energy and chemical applications and other fields. In terms of food contact and medical and health, some aromatic sulfone products have increasingly stringent requirements on the material's resistance to organic solvents (such as chemicals such as ketones) during use.

[0003] For most engineering plastics, more chemical-resistant materials are usually added to enhance the chemical resistance of the main resin. For example, patent application CN104559115A discloses the introduction of ethylene-methacrylate copolymer to improve the chemical resistance of PC / PET alloy, and patent application CN106832848A discloses the preparation of PC / ABS alloy containing LCP and compatibilizer to improve the corrosion resistance of cosmetics. However, there are few reports on the research on improving the chemical resistance of aromatic sulfone polymers. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, the present invention aims to provide an aromatic sulfone polymer having excellent chemical resistance (especially butanone cracking resistance) while maintaining excellent mechanical properties.

[0005] Another object of the present invention is to provide a method for preparing the aromatic sulfone polymer.

[0006] The present invention is achieved through the following technical solutions:

[0007] An aromatic sulfone polymer, the main chain of which contains fluoromethyl side groups, the aromatic sulfone polymer comprises structural units derived from fluoromethyl-containing bisphenol monomers, structural units derived from bisphenol monomers and structural units derived from sulfone monomers, and the fluoromethyl side groups in the aromatic sulfone polymer account for 0.5-5 mol% of the total of the structural units derived from the fluoromethyl-containing bisphenol monomers, the structural units derived from the bisphenol monomers and the structural units derived from the sulfone monomers.

[0008] Preferably, the fluoromethyl group is at least one of a monofluoromethyl group and a difluoromethyl group.

[0009] Preferably, the fluorinated methyl bisphenol monomer is selected from at least one of 2-fluoromethyl-4,4'-biphenol, 3-fluoromethyl-4,4'-biphenol, 2-difluoromethyl-4,4'-biphenol, 3-difluoromethyl-4,4'-biphenol, 2-fluoromethyl-4,4'-dihydroxydiphenyl sulfone, 3-fluoromethyl-4,4'-dihydroxydiphenyl sulfone or 2,2'-bis(2-fluoromethyl-4-hydroxyphenyl)propane.

[0010] Preferably, the phenolic monomer is selected from at least one of 4,4'-dihydroxydiphenyl sulfone, biphenyl diphenol and 2,2'-bis(4-hydroxyphenyl)propane.

[0011] Preferably, the sulfone monomer is selected from at least one of 4,4'-dichlorodiphenyl sulfone, 4,4'-difluorodiphenyl sulfone and bis-(4-chlorophenylsulfone)biphenyl.

[0012] The present invention also provides a method for preparing the aromatic sulfone polymer, comprising the following steps:

[0013] S1. Salt formation reaction

[0014] A solvent, a reaction monomer, a salt-forming agent, and an entrainer are quantitatively added into a reactor protected by high-purity nitrogen, and a solution polycondensation method is adopted to react at 180-230°C for 4-6 hours. During the reaction, the entrainer continuously discharges the reaction water by azeotropy until no water is discharged, the salt-forming reaction is completed, and the entrainer is evaporated;

[0015] S2. Polymerization

[0016] After the azeotropic agent is evaporated, the reaction system is heated to 230-240 °C and maintained for 2-4 hours before the polymerization reaction is completed;

[0017] S3. Post-polymerization processing

[0018] Stop stirring and heating, precipitate the polymer material obtained after the reaction into strips in water, and obtain a powdery material after crushing. Boil it with deionized water for 1 hour, centrifuge and filter, and repeat the operation until the filtrate does not become turbid when tested with silver nitrate, that is, the by-product salt has been washed away. Remove the water from the purified polymer under vacuum drying to obtain an aromatic sulfone polymer.

[0019] Preferably, the reactive monomers include fluorinated methyl bisphenol monomers, phenol monomers and sulfone monomers.

[0020] The fluorinated methyl bisphenol monomer may be selected from at least one of 2-fluoromethyl-4,4'-biphenol, 3-fluoromethyl-4,4'-biphenol, 2-difluoromethyl-4,4'-biphenol, 3-difluoromethyl-4,4'-biphenol, 2-fluoromethyl-4,4'-dihydroxydiphenyl sulfone, 3-fluoromethyl-4,4'-dihydroxydiphenyl sulfone or 2,2'-bis(2-fluoromethyl-4-hydroxyphenyl)propane.

[0021] The phenolic monomer may be selected from at least one of 4,4'-dihydroxydiphenyl sulfone, biphenyl diphenol, or 2,2'-bis(4-hydroxyphenyl)propane.

[0022] The sulfone monomer may be selected from at least one of 4,4'-dichlorodiphenyl sulfone, 4,4'-difluorodiphenyl sulfone or bis-(4-chlorophenylsulfone) biphenyl.

[0023] Preferably, the solvent is selected from sulfolane; the salt-forming agent is selected from sodium carbonate or potassium carbonate; and the azeotropic agent is selected from toluene or xylene.

[0024] The present invention also provides the application of the aromatic sulfone polymer in the field of food or medical hygiene, and can be specifically used in products such as coffee machines and medical disinfection boxes.

[0025] The present invention has the following beneficial effects:

[0026] The present invention introduces a certain proportion of fluoromethyl side groups into the main chain of the aromatic sulfone polymer, which reduces the polarity of the resin to a certain extent and reduces the interaction between chemical reagents and the aromatic sulfone polymer, thereby effectively improving the chemical resistance of the aromatic sulfone polymer (especially the tolerance to ketone reagents) while maintaining excellent mechanical properties (especially tensile strength). DETAILED DESCRIPTION

[0027] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements may be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0028] The reagents used in the embodiments and comparative examples of the present invention are described as follows, but are not limited to these materials:

[0029] Sulfolane: solvent, purity>99.8%;

[0030] 4,4'-Dichlorodiphenyl sulfone: Reaction monomer, purity>99.5%;

[0031] 4,4'-Biphenylene glycol: reactive monomer, purity>99.5%;

[0032] 4,4'-Dihydroxydiphenyl sulfone: Reaction monomer, purity>99.5%;

[0033] 2,2-Bis-4-hydroxyphenylpropane: reaction monomer, purity>99.5%;

[0034] 2-Fluoromethyl-4,4'-biphenylene glycol: reactive monomer, purity>99.5%;

[0035] 2-Fluoromethyl-4,4'-dihydroxydiphenyl sulfone: reactive monomer, purity>99.5%;

[0036] 2-Difluoromethyl-4,4'-biphenyldiphenol: reaction monomer, purity>99.5%;

[0037] 2,2'-Bis(2-fluoromethyl-4-hydroxyphenyl)propane: reaction monomer, purity>99.5%;

[0038] Xylene: azeotropy agent, isomerization grade;

[0039] Sodium carbonate: salt-forming agent, purity >99.5%.

[0040] Comparative Example 1

[0041] 36kg sulfolane, 8.79kg 4,4'-dichlorodiphenyl sulfone (30.6mol) and 5.59kg 4,4'-biphenyl diphenol (30.0mol) were quantitatively added to a 100L reactor protected by high-purity nitrogen, and the mixture was stirred and heated, and 33kg sodium carbonate and 3kg xylene were added. The solution polycondensation method was adopted, and the temperature was slowly raised between 180-210°C for 6h. During the reaction, the entrainer xylene continuously discharged the reaction water through azeotropy until no water was discharged, the salt-forming reaction was completed, and the xylene was evaporated. After that, the reaction system was heated to 240°C, and the polymerization reaction was completed after maintaining for 2.5h. The stirring and heating were stopped, and the polymer material obtained after the reaction was precipitated into strips in water, and the powdery material was obtained after being crushed by a crusher. It was boiled with deionized water for 1h, centrifuged and filtered, and repeated 8-10 times until the filtrate was not turbid when tested with silver nitrate, that is, the by-product salt had been washed away. The purified polymer was dehydrated under vacuum drying to obtain PPSU resin.

[0042] Comparative Example 2

[0043] The implementation process is the same as that of Comparative Example 1, except that 0.2 mol of 2-fluoromethyl-4,4'-biphenol is added and the amount of 4,4'-biphenol is adjusted to 29.8 mol to prepare PPSU resin.

[0044] Comparative Example 3

[0045] The implementation process is the same as that of Comparative Example 1, except that 3.5 mol of 2-fluoromethyl-4,4'-biphenol is added and the amount of 4,4'-biphenol is adjusted to 26.5 mol to prepare PPSU resin.

[0046] Comparative Example 4

[0047] 36 kg of cyclobutane sulfone, 8.79 kg of 4,4'-dichlorodiphenyl sulfone (30.6 mol) and 7.50 kg of 4,4'-dihydroxydiphenyl sulfone (30.0 mol) were quantitatively added into a 100 L reactor protected by high purity nitrogen. The mixture was stirred and heated, and 33 kg of sodium carbonate and 3 kg of xylene were added. The solution polycondensation method was adopted and the temperature was slowly raised between 180-210°C for 6 hours. During the reaction, the entrainer xylene continuously discharged the reaction water through azeotropy until no water was discharged. The salt-forming reaction was completed and the xylene was evaporated. Afterwards, the reaction system was heated to 240°C and maintained for 2.5 hours to terminate the polymerization reaction. Stirring and heating were stopped, and the polymer material obtained after the reaction was precipitated into strips in water. After being crushed by a crusher, a powdery material was obtained. The material was boiled with deionized water for 1 hour and centrifuged and filtered. This process was repeated 8 to 10 times until the filtrate was no longer turbid when tested with silver nitrate, i.e., the by-product salts had been washed away. The purified polymer was dried under vacuum to remove moisture to obtain PES resin.

[0048] Comparative Example 5

[0049] 36 kg of sulfolane, 8.79 kg of 4,4'-dichlorodiphenyl sulfone (30.6 mol) and 6.85 kg of 2,2'-bis(4-hydroxyphenyl)propane (30.0 mol) were quantitatively added into a 100L reactor protected by high-purity nitrogen. The mixture was stirred and heated, and 33 kg of sodium carbonate and 3 kg of xylene were added. The solution polycondensation method was adopted, and the temperature was slowly raised between 200-230°C for 6 hours. During the reaction, the entrainer xylene continuously discharged the reaction water through azeotropy until no water was discharged. The salt-forming reaction was completed and the xylene was evaporated. Afterwards, the reaction system was heated to 240°C and maintained for 2.5 hours to terminate the polymerization reaction. Stirring and heating were stopped, and the polymer material obtained after the reaction was precipitated into strips in water. After being crushed by a crusher, a powdery material was obtained. The material was boiled with deionized water for 1 hour and centrifuged and filtered. This process was repeated 8 to 10 times until the filtrate was no longer turbid when tested with silver nitrate, i.e., the by-product salts had been washed away. The purified polymer was dried under vacuum to remove moisture to obtain PSU resin.

[0050] Example 1

[0051] The implementation process is the same as that of Comparative Example 1, except that 0.32 mol of 2-fluoromethyl-4,4'-biphenol is added and the amount of 4,4'-biphenol is adjusted to 29.68 mol to prepare PPSU resin.

[0052] Example 2

[0053] The implementation process is the same as that of Comparative Example 1, except that 1.0 mol of 2-fluoromethyl-4,4'-biphenol is added and the amount of 4,4'-biphenol is adjusted to 29 mol to prepare PPSU resin.

[0054] Example 3

[0055] The implementation process is the same as that of Comparative Example 1, except that 3 mol of 2-fluoromethyl-4,4'-biphenol is added and the amount of 4,4'-biphenol is adjusted to 27 mol to prepare PPSU resin.

[0056] Example 4

[0057] The implementation process is the same as that of Comparative Example 1, except that 2 mol of 2-fluoromethyl-4,4'-biphenol is added and the amount of 4,4'-biphenol is adjusted to 28 mol to prepare PPSU resin.

[0058] Example 5

[0059] The implementation process is the same as that of Comparative Example 1, except that 2 mol of 2-difluoromethyl-4,4'-biphenol is added and the amount of 4,4'-biphenol is adjusted to 28 mol to prepare PPSU resin.

[0060] Example 6

[0061] The implementation process is the same as that of Comparative Example 4, except that 2 mol of 2-fluoromethyl-4,4'-dihydroxydiphenyl sulfone is added and the amount of 4,4'-dihydroxydiphenyl sulfone is adjusted to 28 mol to prepare PES resin.

[0062] Example 7

[0063] The implementation process is the same as that of Comparative Example 5, except that 1 mol of 2,2'-bis(2-fluoromethyl-4-hydroxyphenyl)propane is added and the amount of 2,2'-bis(4-hydroxyphenyl)propane is adjusted to 29 mol to prepare PSU resin.

[0064] Related performance test methods:

[0065] (1) Determination of the molar percentage of fluoromethyl side groups: 1H NMR test method, using deuterated chloroform or deuterated DMSO as solvent, using a 400M NMR test instrument to calculate the molar percentage of fluoromethyl side groups by comparing the ratio of the methyl proton peak to the main chain benzene ring proton peak.

[0066] (2) Chemical resistance: The aromatic sulfone composition was injection molded at 360°C by an injection molding machine to obtain a tubular product with a thickness of 2 mm, a length of 20 mm, and an inner diameter of 20 mm. The tubular product was immersed in butanone, and the time t from the beginning of immersion to cracking of the product was recorded; the longer the time, the better the chemical resistance.

[0067] (3) Tensile strength: measured according to ISO527-2-2012. The test conditions are 23°C and 10 mm / min.

[0068] Table 1 Data results of aromatic sulfone polymers of Comparative Examples 1-5

[0069]

[0070] Table 2 Data results of aromatic sulfone polymers of Examples 1-7

[0071]

[0072] It can be seen from the above results that the present invention introduces a certain proportion of fluoromethyl side groups on the main chain of the aromatic sulfone polymer, which can effectively improve the chemical resistance of the aromatic sulfone polymer (especially the tolerance to ketone reagents) while maintaining excellent mechanical properties (especially tensile strength); when the molar ratio of the fluoromethyl side groups is between 0.5-5%, better tensile strength and chemical resistance can be obtained.

[0073] By comparing Examples 1-5 with Comparative Examples 1-3, it can be seen that by introducing a certain proportion of fluoromethyl side groups into the main chain of the PPSU polymer, the chemical resistance is significantly improved, and excellent mechanical properties are taken into account (the cracking time of the ketone solvent resistance test is greater than 100s, and the tensile strength is guaranteed to be not less than 70Mpa); it can be seen from Comparative Example 2 that when the proportion of fluoromethyl side groups is lower than 0.5%, the chemical resistance is not significantly improved, and the tensile strength remains almost unchanged; it can be seen from Comparative Example 3 that when the proportion of fluoromethyl side groups is higher than 5%, although it has good chemical resistance, the tensile strength is significantly reduced compared with the PPSU resin without the introduction of fluoromethyl side groups (Comparative Example 1) (the tensile strength is only 58Mpa, a decrease of 23%).

[0074] By comparing Example 6 with Comparative Example 4, introducing a certain proportion of fluoromethyl side groups into the main chain of the PES polymer can also significantly improve its chemical resistance while taking into account excellent mechanical properties (the cracking time of the ketone solvent resistance test can reach more than 70s, and the tensile strength is guaranteed to be no less than 88Mpa).

[0075] By comparing Example 7 with Comparative Example 5, introducing a certain proportion of fluoromethyl side groups into the main chain of the PSU polymer can also significantly improve its chemical resistance while taking into account excellent mechanical properties (the cracking time of the ketone solvent resistance test can reach more than 60s, and the tensile strength is guaranteed to be no less than 68Mpa).

Claims

1. An aromatic sulfone polymer, characterized in that The main chain of the aromatic sulfone polymer contains fluoromethyl side groups, the aromatic sulfone polymer comprises structural units derived from fluoromethyl-containing bisphenol monomers, structural units derived from bisphenol monomers and structural units derived from sulfone monomers, and the fluoromethyl side groups in the aromatic sulfone polymer account for 0.5-5 mol% of the total of the structural units derived from the fluoromethyl-containing bisphenol monomers, the structural units derived from the bisphenol monomers and the structural units derived from the sulfone monomers. The fluorinated methyl bisphenol monomer is selected from at least one of 2-fluoromethyl-4,4'-biphenol, 3-fluoromethyl-4,4'-biphenol, 2-difluoromethyl-4,4'-biphenol, 3-difluoromethyl-4,4'-biphenol, 2-fluoromethyl-4,4'-dihydroxydiphenyl sulfone, 3-fluoromethyl-4,4'-dihydroxydiphenyl sulfone or 2,2'-bis(2-fluoromethyl-4-hydroxyphenyl)propane.

2. The aromatic sulfone polymer according to claim 1, characterized in that The phenol monomer is selected from at least one of 4,4'-dihydroxydiphenyl sulfone, biphenyl diphenol or 2,2'-bis(4-hydroxyphenyl)propane; the sulfone monomer is selected from at least one of 4,4'-dichlorodiphenyl sulfone, 4,4'-difluorodiphenyl sulfone or bis-(4-chlorophenylsulfone)biphenyl.

3. The method for preparing an aromatic sulfone polymer according to any one of claims 1 to 2, characterized in that: The following steps are involved: S1. Salt formation reaction A solvent, a reaction monomer, a salt-forming agent, and an entrainer are quantitatively added into a reactor protected by high-purity nitrogen, and a solution polycondensation method is adopted to react at 180-230°C for 4-6 hours. During the reaction, the entrainer continuously discharges the reaction water by azeotropy until no water is discharged, the salt-forming reaction is completed, and the entrainer is evaporated; S2. Polymerization After the azeotropic agent is evaporated, the reaction system is heated to 230-240°C and maintained for 2-4 hours before the polymerization reaction is completed; S3. Post-polymerization processing Stop stirring and heating, precipitate the polymer material obtained after the reaction into strips in water, crush it to obtain a powdery material, boil it with deionized water for 1-1.5 hours, centrifuge and filter, repeat the operation until the filtrate is not turbid when tested with silver nitrate, that is, the by-product salt has been washed away, and remove the water from the purified polymer under vacuum drying to obtain an aromatic sulfone polymer; the reaction monomers include fluorinated methyl bisphenol monomers, phenol monomers and sulfone monomers; the fluorinated methyl bisphenol monomers are selected from 2-fluoromethyl-4,4'-biphenol, 3-fluoromethyl-4,4'-biphenol, 2- At least one of difluoromethyl-4,4'-biphenol, 3-difluoromethyl-4,4'-biphenol, 2-fluoromethyl-4,4'-dihydroxydiphenyl sulfone, 3-fluoromethyl-4,4'-dihydroxydiphenyl sulfone or 2,2'-bis(2-fluoromethyl-4-hydroxyphenyl)propane; the phenolic monomer is selected from at least one of 4,4'-dihydroxydiphenyl sulfone, biphenol or 2,2'-bis(4-hydroxyphenyl)propane; the sulfone monomer is selected from at least one of 4,4'-dichlorodiphenyl sulfone, 4,4'-difluorodiphenyl sulfone or bis-(4-chlorophenylsulfone)biphenyl.

4. The method for preparing an aromatic sulfone polymer according to claim 3, characterized in that: The solvent is selected from sulfolane; the salt-forming agent is selected from sodium carbonate or potassium carbonate; and the azeotropic agent is selected from toluene or xylene.

5. Use of the aromatic sulfone polymer according to any one of claims 1 to 2 in the field of food or medical hygiene.

Images