Preparation method of high-purity LCP material

[0027] The preparation method of the high-purity LCP material of the present application comprises the following steps:

[0028] S1: Acetylation of HBA and HNA

[0029] Add HBA/HNA, acetic anhydride and catalyst A into the reaction vessel, raise the temperature to 140°C, pass through protective nitrogen gas and start stirring, the stirring speed is 200-300rpm, under this condition, HBA/HNA reacts with acetic anhydride to form ester compound, and condensed acetic anhydride to reflux for acetylation reaction, then stop the reaction, transfer the reactant to a container with deionized water, wait for the white crystals to precipitate, and finally wash and dry the white crystals for later use, the white crystals here for ABA/ANA;

[0030] S2: Preparation of high-purity LCP materials

[0031] Add the ABA, ANA and catalyst B prepared in S1 into the reaction vessel, transfer the reaction vessel to the salt bath and pass nitrogen to remove the air in the system, raise the temperature to 230-290°C, keep warm for the reaction, and then vacuumize Slowly raise the temperature to 300-320°C, keep it warm for the reaction, and finally stop the reaction, and cool to about 80°C to obtain high-purity LCP material.

[0032] Further, the molar ratio of HBA/HNA to acetic anhydride in S1 is 1:1-3.

[0033] Further, catalyst A in S1 is any one of vanadyl sulfate, zinc acetate and 1-methylimidazole.

[0034] Further, the amount of catalyst A added in S1 accounts for 0.05%-0.2% of the total mass of the reaction raw materials.

[0035] Further, the acetylation reaction time in S1 is 1-4h.

[0036] Further, the molar ratio of ABA to ANA in S2 is 1.5-4:1.

[0037] Further, catalyst B in S2 is any one of antimony trioxide, zinc acetate and n-butyl titanate.

[0038] Further, the amount of catalyst B added in S2 accounts for 0.01%-0.05% of the total mass of the reaction raw materials.

[0039] Further, before the vacuuming reaction in S2, two heat preservation reactions need to be carried out, the temperature of the first heat preservation reaction needs to be controlled at 230-250°C, and the temperature of the second heat preservation reaction needs to be controlled at 270-290°C.

[0040] Further, in S2, the reaction time of heat preservation after the first temperature rise is 3-5 hours, the reaction time of heat preservation after the second temperature rise is 2-4 hours, and the reaction time of heat preservation after the third time of vacuuming is 1-2 hours.

[0041] In the preparation method of the present invention, a high-purity LCP material is prepared by a two-step method. First, through synergistic optimization of the ratio of HBA/HNA and acetic anhydride, the type and content of the catalyst, and the acetylation time that affect the degree of acetylation of HBA/HNA, the maximum degree of On the one hand, the acetylation of HBA/HNA is completely guaranteed, and the purity of TLCP is improved by optimizing the ratio of ABA/ANA after acetylation, the type and content of the catalyst, and the reaction temperature and time, so that the comprehensive performance of the LCP material prepared by the present invention Excellent, can better meet the application requirements. In addition, the preparation method of the present invention has a simple overall process, easy operation, meets the requirements of mass production and manufacturing, and has good application prospects.

[0043] Example 1:

[0044] S1: Acetylation of HBA and HNA

[0045]P-hydroxybenzoic acid (HBA) and acetic anhydride with a molar ratio of 1:2 were added to the three-necked flask, and the catalyst zinc acetate of 0.05% mass fraction was added simultaneously; Turn on stirring at a stirring speed of 300rpm/min, keep warm at this temperature for 2h to carry out the acetylation reaction, transfer it to a beaker with deionized water after the reaction, wait for the crystals to precipitate, and finally wash and dry the precipitated crystals (ABA) for later use .

[0046] Add 2-hydroxy-6-naphthoic acid (HNA) and acetic anhydride with a molar ratio of 1:2 into the three-necked flask, and at the same time add 0.05% mass fraction of the catalyst 1-methylimidazole; raise the temperature to react in the three-necked flask The temperature of the system reaches 140°C and the stirring is started at the same time. The stirring speed is 300rpm/min. The acetylation reaction is carried out at this temperature for 2 hours. The crystals (ANA) were washed and dried for later use.

[0047] S2: Preparation of high-purity LCP materials

[0048] ABA and ANA are added in the three-necked flask with a molar ratio of 7:3, then the catalyst zinc acetate of mass fraction 0.02% is added, the three-necked flask is transferred to the salt bath and the air in the nitrogen removal system is passed into the three-necked flask, the first Once the temperature was raised to 230°C for 3 hours, and for the second time, the temperature was raised to 270°C for 2 hours, and then the temperature was slowly raised to 300°C for 1 hour while vacuuming, and finally the reaction was stopped and cooled to about 80°C to take out, that is High purity LCP material is available.

[0049] Example 2:

[0050] S1: Acetylation of HBA and HNA

[0051] P-hydroxybenzoic acid (HBA) and acetic anhydride with a molar ratio of 1:3 were added into the there-necked flask, and the catalyst zinc acetate of 0.08% mass fraction was added simultaneously; Turn on the stirring, the stirring speed is 300rpm/min, keep warm at this temperature for 3h to carry out the acetylation reaction, transfer it to a beaker with deionized water after the reaction, wait for the crystals to precipitate, and finally wash and dry the precipitated crystals (ABA) for later use .

[0052] Add 2-hydroxy-6-naphthoic acid (HNA) and acetic anhydride with a molar ratio of 1:3 into the three-necked flask, and at the same time add 0.08% mass fraction of the catalyst 1-methylimidazole; raise the temperature to react in the three-necked flask The temperature of the system reaches 140°C and the stirring is started at the same time. The stirring speed is 300rpm/min. The acetylation reaction is carried out at this temperature for 3 hours. The crystals (ANA) were washed and dried for later use.

[0053] S2: Preparation of high-purity LCP materials

[0054] ABA and ANA are added in the three-necked flask with a molar ratio of 7:3, then the catalyst zinc acetate of mass fraction 0.02% is added, the three-necked flask is transferred to the salt bath and the air in the nitrogen removal system is passed into the three-necked flask, the first Once the temperature is raised to 240°C for 3 hours, and for the second time, the temperature is raised to 280°C for 2 hours, and then the temperature is slowly raised to 310°C for 1 hour while vacuuming, and finally the reaction is stopped and cooled to about 80°C. High purity LCP material is available.