Preparation method of weather-resistant and solvent-resistant copolymerized polycarbonate

Abstract

The invention discloses a preparation method of weather-resistant and solvent-resistant copolymerized polycarbonate, and belongs to the technical field of copolymerized polycarbonate, a polycarbonate copolymer is added into a reaction kettle and dissolved with dichloromethane, a functional filler is added into the reaction kettle, ultrasonic dispersion is performed after stirring, a photoinitiator DMPA is added into the reaction kettle, stirring is performed for 2-4 hours, and the weather-resistant and solvent-resistant copolymerized polycarbonate is obtained. Stirring under ultraviolet irradiation, adding di (methacryloyloxyethyl) hydrogen phosphate, stirring to react for 2.5-3 hours, centrifugally filtering, washing a filter cake with absolute ethyl alcohol, and drying in vacuum to obtain the weather-resistant and solvent-resistant copolymerized polycarbonate. The copolymerized polycarbonate prepared by the method disclosed by the invention has good weather resistance and solvent resistance, the flame-retardant substance and the polycarbonate copolymer are bridged by taking the sulfydryl-containing functional filler as a medium, the flame-retardant stability of the product is improved on the premise of not excessively influencing the light transmittance, and the application range of the copolymerized polycarbonate product is favorably widened.

Description

Technical Field

[0001] The invention belongs to the technical field of copolymer polycarbonate, and particularly relates to a method for preparing weather-resistant and solvent-resistant copolymer polycarbonate. Background Art

[0002] Polycarbonate (PC) is a common thermoplastic engineering plastic. It is a high molecular polymer synthesized from bisphenol A and phosgene. It has carbonate groups and is an amorphous thermoplastic resin. Polycarbonate has high transparency and high impact resistance. It is widely used in products such as DVD discs, car headlights and billboards. However, ordinary polycarbonate materials have poor solvent resistance and cannot be used in some fields. The commonly used method is to modify ordinary polycarbonate, such as compounding ABS plastics or PBT plastics.

[0003] The Chinese patent with the announcement number CN117285809B announced a new flame-retardant and weather-resistant polycarbonate composite material and its preparation process, which improves the flame retardancy and weather resistance of polycarbonate materials by compounding raw materials such as acrylonitrile-butadiene-styrene copolymer, modified multi-walled carbon nanotubes and modified flame retardant. This modification method has little effect on improving the solvent resistance of polycarbonate, while copolymer polycarbonate is synthesized by different types of carbonate monomers or binary mixtures under the action of catalysts, such as a mixture of polymethyl acrylate carbonate and styrene carbonate, or a mixture of epoxy resin and carbonate, etc., which is more excellent in solvent resistance.

[0004] However, adding fillers such as carbon nanotubes will reduce the light transmittance of polycarbonate, and the added flame retardants will also precipitate with aging, and the flame retardant properties will decrease. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing weather-resistant and solvent-resistant copolymer polycarbonate, by using a functional filler containing a mercapto group as a medium to bridge a flame retardant substance and a polycarbonate copolymer, thereby improving the flame retardant stability of the product.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A method for preparing weather-resistant and solvent-resistant copolymer polycarbonate comprises the following steps:

[0008] Step 1: Add 4-(1,2,2-triphenylethylene)phenol, Sal enCoC l as a catalyst, PPNC l as a co-catalyst, allyl glycidyl ether, and silicon-containing epoxide into a reaction kettle, stir and mix at 200-250 r / min for 5-10 minutes, then stir and react at 25-30° C. and 3-3.2 MPa CO2 pressure for 16-18 hours, dissolve the reaction product in dichloromethane, transfer it to a mixed solution for precipitation, filter, and vacuum dry to obtain a polycarbonate copolymer;

[0009] Furthermore, the mixed solution is prepared by mixing anhydrous ethanol and 37% hydrochloric acid in a volume ratio of 20:1.

[0010] Furthermore, the mass ratio of 4-(1,2,2-triphenylethylene)phenol, Sal enCoC l, PPNC l, allyl glycidyl ether and silicon-containing epoxide is 3.5:6.4:5.74:91.3:467.

[0011] Step 2: Add the polycarbonate copolymer into a reactor and dissolve it in dichloromethane, add functional filler to the reaction, stir at 200-300 r / min for 5-10 min, and then ultrasonically disperse for 10-15 min, then add photoinitiator DMPA into the reactor, stir for 0.5-0.6 h under ultraviolet light with a light intensity of 6-8 mW / cm and a wavelength of 365 nm, then add di(methacryloyloxyethyl) hydrogen phosphate, stir the reaction for 2.5-3 h, centrifuge and filter, wash the filter cake with anhydrous ethanol for 3-5 times, and vacuum dry to obtain weather-resistant and solvent-resistant copolymer polycarbonate.

[0012] Furthermore, the usage ratio of the polycarbonate copolymer, dichloromethane, functional filler, photoinitiator DMPA and di(methacryloyloxyethyl) hydrogen phosphate is 5.5 g: 50-60 mL: 0.33-0.44 g: 0.06-0.08 g: 0.3134 g.

[0013] Further, the silicon-containing epoxide is prepared by the following steps:

[0014] Add epichlorohydrin and sodium hydroxide to the reaction kettle, stir for 10-15 minutes at 20-25°C and 150-200r / min, then drop trimethylsilanol into the reaction kettle, stir and react for 2-2.5 hours, cool and crystallize, filter and remove salt, remove sodium chloride and unreacted sodium hydroxide produced by the reaction, dry the filtrate with anhydrous magnesium sulfate to remove water, and fractionate under reduced pressure to obtain silicon-containing epoxide. The reaction process is as follows:

[0015]

[0016] Furthermore, the usage ratio of epichlorohydrin, sodium hydroxide and trimethylsilanol is 92.5g:60g:90.2g.

[0017] Furthermore, the functional filler is prepared by the following steps:

[0018] Add anhydrous ethanol and deionized water into a reactor, stir at 35-40° C. and 800-1000 r / min for 10-15 min, then add tetraethoxysilane into the reactor, continue stirring for 60-80 min, drop 25% ammonia water, stir at 200-300 r / min for 5-6 h, then add mercaptopropyltrimethoxysilane, stir for 8-10 h, centrifuge and filter, wash the filter cake with deionized water and anhydrous ethanol for 3-5 times respectively, vacuum dry and grind to obtain a functional filler.

[0019] Furthermore, the usage ratio of anhydrous ethanol, deionized water, tetraethoxysilane, ammonia water, and mercaptopropyltrimethoxysilane is 5 mL: 45 mL: 0.2 mL: 0.5 mL: 0.4 mL.

[0020] Beneficial effects of the present invention:

[0021] The copolymer polycarbonate prepared by the method of the present invention has good weather resistance and solvent resistance. By using a functional filler containing a mercapto group as a medium to bridge the flame retardant substance and the polycarbonate copolymer, the flame retardant stability of the product is improved without excessively affecting its light transmittance, which helps to broaden the application range of the copolymer polycarbonate product.

[0022] The silicon-containing epoxide of the present invention contains methoxysilyl groups, which can improve the solvent resistance of copolymerized polycarbonate and improve its interfacial compatibility, and help to improve the dispersibility of functional fillers in polymers. In the preparation process of the functional filler, tetraethoxysilane is reacted in an ethanol aqueous solution to form nano-silicon dioxide by a one-step method, and then mercaptopropyltrimethoxysilane is self-condensed to obtain a functional filler with a core-shell structure, and the functional filler can improve the mechanical properties of the copolymerized polycarbonate.

[0023] Allyl glycidyl ether introduces a carbon-carbon double bond into the polycarbonate copolymer, and the shell of the functional filler contains a thiol group, which reacts with the carbon-carbon double bond through click chemistry to connect di(methacryloyloxyethyl) hydrogen phosphate and the polycarbonate copolymer matrix, reducing the aging migration of the phosphoric acid flame retardant and improving the flame retardant stability. 4-(1,2,2-triphenylethylene)phenol has a strong stability to ultraviolet light excitation, which can improve the efficiency of the click chemistry reaction and further improve the stability of the connection of the phosphoric acid flame retardant. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0025] Embodiment 1: This embodiment provides a method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate, comprising the following steps:

[0026] S1: Add 92.5 kg of epichlorohydrin and 60 kg of sodium hydroxide into a reactor, stir for 10 min at 20°C and 150 r / min, then drop 90.2 kg of trimethylsilanol into the reactor, stir and react for 2 h, cool and crystallize, filter and remove salt, remove sodium chloride and unreacted sodium hydroxide produced by the reaction, dry the filtrate with anhydrous magnesium sulfate to remove water, and perform reduced pressure fractionation to obtain silicon-containing epoxide.

[0027] S2: Add 50L of anhydrous ethanol and 450L of deionized water into the reactor, stir at 35°C and 800r / min for 10min, then add 2L of tetraethoxysilane into the reactor, continue stirring for 60min, drop 5L of 25% ammonia water and stir at 200r / min for 5h, then add 4L of mercaptopropyltrimethoxysilane, stir and react for 8h, centrifuge and filter, wash the filter cake with deionized water and anhydrous ethanol for 3 times respectively, vacuum dry and crush to obtain functional filler.

[0028] S3: 3.5 kg 4-(1,2,2-triphenylethylene)phenol, 6.4 kg Sal enCoCl as a catalyst, 5.74 kg PPNCl as a co-catalyst, 91.3 kg allyl glycidyl ether and 467 kg silicon-containing epoxide were added into a reactor, stirred and mixed at 200 r / min for 5 min, then stirred and reacted at 25°C and 3 MPa CO2 pressure for 16 h, the reaction product was dissolved with dichloromethane, transferred to a mixed solution for precipitation, filtered, and vacuum dried to obtain a polycarbonate copolymer, wherein the mixed solution is a mixture of anhydrous ethanol and 37% hydrochloric acid by mass in a volume ratio of 20:1.

[0029] S4: Add 5.5 kg of polycarbonate copolymer into a reactor and dissolve it in 50 L of dichloromethane, add 0.33 kg of functional filler into the reaction, stir at 200 r / min for 5 min, and then ultrasonically disperse for 10 min, add 0.06 kg of photoinitiator DMPA into the reactor, stir for 0.5 h under ultraviolet light with an intensity of 6 mW / cm and a wavelength of 365 nm, and then add 0.3134 kg of di(methacryloyloxyethyl) hydrogen phosphate, stir the reaction for 2.5 h, centrifuge and filter, wash the filter cake three times with anhydrous ethanol, and vacuum dry to obtain a weather-resistant and solvent-resistant copolymer polycarbonate.

[0030] Embodiment 2: This embodiment provides a method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate, comprising the following steps:

[0031] S1: Add 92.5 kg of epichlorohydrin and 60 kg of sodium hydroxide into a reactor, stir for 12 min at 22 ° C and 180 r / min, then drop 90.2 kg of trimethylsilanol into the reactor, stir and react for 2.2 h, cool and crystallize, filter and remove salt, remove sodium chloride and unreacted sodium hydroxide produced by the reaction, dry the filtrate with anhydrous magnesium sulfate to remove water, and perform reduced pressure fractionation to obtain silicon-containing epoxide.

[0032] S2: Add 50L of anhydrous ethanol and 450L of deionized water into the reactor, stir at 38°C and 900r / min for 12min, then add 2L of tetraethoxysilane into the reactor, continue stirring for 70min, drop 5L of 25% ammonia water, stir at 250r / min for 5.5h, then add 4L of mercaptopropyltrimethoxysilane, stir for 9h, centrifuge and filter, wash the filter cake with deionized water and anhydrous ethanol for 4 times respectively, vacuum dry and grind to obtain functional filler.

[0033] S3: 3.5 kg 4-(1,2,2-triphenylethylene)phenol, 6.4 kg Sal enCoCl as a catalyst, 5.74 kg PPNCl as a co-catalyst, 91.3 kg allyl glycidyl ether and 467 kg silicon-containing epoxide were added into a reactor, stirred and mixed at 230 r / min for 8 min, then stirred and reacted at 28°C and 3.1 MPa CO2 pressure for 17 h, the reaction product was dissolved with dichloromethane, transferred to a mixed solution for precipitation, filtered, and vacuum dried to obtain a polycarbonate copolymer, wherein the mixed solution is a mixture of anhydrous ethanol and 37% hydrochloric acid by mass in a volume ratio of 20:1.

[0034] S4: Add 5.5 kg of polycarbonate copolymer into a reactor and dissolve it in 55 L of dichloromethane, add 0.38 kg of functional filler into the reaction, stir at 250 r / min for 8 min and then ultrasonically disperse for 12 min, then add 0.07 kg of photoinitiator DMPA into the reactor, stir for 0.55 h under ultraviolet light with an intensity of 7 mW / cm and a wavelength of 365 nm, then add 0.3134 kg of di(methacryloyloxyethyl) hydrogen phosphate, stir the reaction for 2.8 h, centrifuge and filter, wash the filter cake with anhydrous ethanol 4 times, and vacuum dry to obtain weather-resistant and solvent-resistant copolymer polycarbonate.

[0035] Embodiment 3: This embodiment provides a method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate, comprising the following steps:

[0036] S1: Add 92.5 kg of epichlorohydrin and 60 kg of sodium hydroxide into a reactor, stir for 15 min at 25 ° C and 200 r / min, then drop 90.2 kg of trimethylsilanol into the reactor, stir and react for 2.5 h, cool and crystallize, filter and remove salt, remove sodium chloride and unreacted sodium hydroxide produced by the reaction, dry the filtrate with anhydrous magnesium sulfate to remove water, and distill under reduced pressure to obtain silicon-containing epoxide.

[0037] S2: Add 50L of anhydrous ethanol and 450L of deionized water into the reactor, stir at 40°C and 1000r / min for 15min, then add 2L of tetraethoxysilane into the reactor, continue stirring for 80min, drop 5L of 25% ammonia water, stir at 300r / min for 6h, then add 4L of mercaptopropyltrimethoxysilane, stir for 10h, centrifuge and filter, wash the filter cake with deionized water and anhydrous ethanol for 5 times respectively, vacuum dry and crush to obtain functional filler.

[0038] S3: 3.5 kg 4-(1,2,2-triphenylethylene)phenol, 6.4 kg Sal enCoCl as a catalyst, 5.74 kg PPNCl as a co-catalyst, 91.3 kg allyl glycidyl ether and 467 kg silicon-containing epoxide were added into a reactor, stirred and mixed at 250 r / min for 10 min, then stirred and reacted at 30°C and 3.2 MPa CO2 pressure for 18 h, the reaction product was dissolved with dichloromethane, transferred to a mixed solution for precipitation, filtered, and vacuum dried to obtain a polycarbonate copolymer, wherein the mixed solution is a mixture of anhydrous ethanol and 37% hydrochloric acid by mass in a volume ratio of 20:1.

[0039] S4: Add 5.5 kg of polycarbonate copolymer into a reactor and dissolve it in 60 L of dichloromethane, add 0.44 kg of functional filler into the reaction, stir at 300 r / min for 10 min and then ultrasonically disperse for 15 min, then add 0.08 kg of photoinitiator DMPA into the reactor, stir for 0.6 h under ultraviolet light with an intensity of 8 mW / cm and a wavelength of 365 nm, then add 0.3134 kg of di(methacryloyloxyethyl) hydrogen phosphate, stir the reaction for 3 h, centrifuge and filter, wash the filter cake with anhydrous ethanol 5 times, and vacuum dry to obtain weather-resistant and solvent-resistant copolymer polycarbonate.

[0040] Comparative Example 1: Based on Example 3, in step S3, the silicon-containing epoxide is replaced with propylene oxide of the same molar mass, and the other steps remain unchanged to prepare a copolymerized polycarbonate.

[0041] Comparative Example 2: Based on Example 3, no functional filler was added in step S4, and the other steps remained unchanged to prepare copolymerized polycarbonate.

[0042] Comparative Example 3: Based on Example 3, in step S4, the functional filler is replaced with ordinary nano-silicon dioxide, and the other steps remain unchanged to prepare copolymerized polycarbonate.

[0043] Comparative Example 4: Based on Example 3, a polycarbonate copolymer is prepared without adding 4-(1,2,2-triphenylethylene)phenol in step S3, and the other steps remain unchanged to prepare a copolymer polycarbonate.

[0044] Comparative Example 5: Based on Example 3, di(methacryloyloxyethyl) hydrogen phosphate was not added in step S4, and the other steps remained unchanged to prepare a copolymerized polycarbonate.

[0045] The raw materials used in the examples and comparative examples are all commercially available products.

[0046] Performance tests were conducted on Examples 1 to 3 and Comparative Examples 1 to 5, and samples were prepared from different copolymerized polycarbonates according to the corresponding standards. With reference to GB / T 1040.2-2006, the tensile strength and elongation at break of different samples were tested; with reference to ASTM D543, the solvent resistance of the samples was tested, peanut oil was applied to the surface of the samples with a thickness of 3.2 mm, and the appearance changes were observed, which were divided into four levels: A (no cracks), B (cracks), C (severe cracks) and D (breaks); with reference to UL94, the flame retardant properties of the samples with a thickness of 1.6 mm were tested, and the flame retardant levels were divided into HB, V0, V1, V2, 5VA, and 5VB; the samples were placed in a UV aging box, irradiated under 340 nm UV light for 800 h, and then transferred to anhydrous ethanol for immersion for 72 h, and their flame retardant properties were tested again.

[0047] The results are shown in Table 1:

[0048] Table 1

[0049]

[0050] As can be seen from Table 1, the copolycarbonates in Examples 1 to 3 have better mechanical properties, solvent resistance, light transmittance and flame retardant properties. Comparative Example 1 shows that silicon-containing epoxide can improve the solvent resistance of copolycarbonate, and its tensile strength and elongation at break decrease because the methoxysilyl group in the silicon-containing epoxide can improve chemical stability and improve interfacial compatibility, and improve the dispersibility of functional fillers; Comparative Examples 2, 3 and 5 show that functional fillers can improve the mechanical properties of copolycarbonate, and the functional filler surface contains thiol, which reacts with carbon-carbon double bonds by click chemistry to connect di(methacryloyloxyethyl) hydrogen phosphate and polycarbonate copolymer matrix, reduce the aging migration of phosphoric acid flame retardant, and improve flame retardant stability; the flame retardant properties of copolycarbonate after aging treatment in Comparative Example 4 decrease because 4-(1,2,2-triphenylethylene)phenol has strong stability to ultraviolet light excitation, which can improve the efficiency of click chemistry reaction and improve the stability of phosphoric acid flame retardant connection.

[0051] It should be noted that, in this article, terms such as "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0052] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate, characterized in that: The steps include: Step 1: Add 4-(1,2,2-triphenylethylene)phenol, SalenCoCl, PPNCl, allyl glycidyl ether, and silicon-containing epoxide into a reaction kettle, stir and mix at 200-250 r / min for 5-10 min, then stir and react at 25-30° C. and 3-3.2 MPa CO2 pressure for 16-18 h, dissolve the reaction product in dichloromethane, transfer it to a mixed solution for precipitation, filter, and vacuum dry to obtain a polycarbonate copolymer; Step 2: Add the polycarbonate copolymer into a reactor and dissolve it in dichloromethane, add functional filler to the reaction, stir at 200-300 r / min for 5-10 min, and then ultrasonically disperse for 10-15 min, then add photoinitiator DMPA into the reactor, stir for 0.5-0.6 h under ultraviolet light with a light intensity of 6-8 mW / cm and a wavelength of 365 nm, then add di(methacryloyloxyethyl) hydrogen phosphate, stir the reaction for 2.5-3 h, centrifuge and filter, wash the filter cake with anhydrous ethanol for 3-5 times, and vacuum dry to obtain weather-resistant and solvent-resistant copolymer polycarbonate.

2. The method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate according to claim 1, characterized in that: The mixed solution is prepared by mixing anhydrous ethanol and hydrochloric acid with a mass fraction of 37% in a volume ratio of 20:

1.

3. The method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate according to claim 1, characterized in that: The mass ratio of the 4-(1,2,2-triphenylethylene)phenol, SalenCoCl, PPNCl, allyl glycidyl ether and silicon-containing epoxide is 3.5:6.4:5.74:91.3:

467.

4. The method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate according to claim 1, characterized in that: The usage ratio of the polycarbonate copolymer, dichloromethane, functional filler, photoinitiator DMPA and di(methacryloyloxyethyl) hydrogen phosphate is 5.5g:50-60mL:0.33-0.44g:0.06-0.08g:0.3134g.

5. The method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate according to claim 1, characterized in that: The silicon-containing epoxide is prepared by the following steps: Add epichlorohydrin and sodium hydroxide into a reaction kettle, stir at 20-25°C and 150-200r / min for 10-15min, then drop trimethylsilanol into the reaction kettle, stir and react for 2-2.5h, cool and crystallize, filter and remove salt, dry the filtrate with anhydrous magnesium sulfate to remove water, and perform reduced pressure fractionation to obtain silicon-containing epoxide.

6. The method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate according to claim 5, characterized in that: The usage ratio of epichlorohydrin, sodium hydroxide and trimethylsilanol is 92.5g:60g:90.2g.

7. The method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate according to claim 1, characterized in that: The functional filler is prepared by the following steps: Anhydrous ethanol and deionized water are added to a reaction kettle, stirred at 35-40° C. and 800-1000 r / min for 10-15 min, and then tetraethoxysilane is added to the reaction kettle, and stirring is continued for 60-80 min. After 25 wt % ammonia water is added dropwise, stirring is carried out at 200-300 r / min for 5-6 h, and then mercaptopropyltrimethoxysilane is added, stirring is carried out for 8-10 h, and centrifugal filtration is performed. The filter cake is washed with deionized water and anhydrous ethanol for 3-5 times respectively, vacuum dried, and crushed to obtain a functional filler.

8. The method for preparing a weather-resistant and solvent-resistant copolymer polycarbonate according to claim 7, characterized in that: The usage ratio of anhydrous ethanol, deionized water, tetraethoxysilane, ammonia water, and mercaptopropyltrimethoxysilane is 5 mL: 45 mL: 0.2 mL: 0.5 mL: 0.4 mL.

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