CN111019129A - Low-thermal expansion coefficient soluble polyimide resin powder and preparation method thereof - Google Patents

Abstract

The invention discloses a soluble polyimide resin powder with low thermal expansion coefficient and a preparation method thereof. The preparation method of the low-thermal expansion coefficient soluble polyimide resin powder comprises the following steps: firstly, 4 '-diamino-2, 2' -bistrifluoromethylbiphenyl reacts with dianhydride monomer with a limited structure in an aprotic polar solvent to obtain a segmented polyamic acid resin solution; adding diamine monomer and non-proton polar solvent with limited structure, and then adding dianhydride monomer with limited structure in batches for reaction to obtain soluble polyamic acid resin solution with low thermal expansion coefficient; finally, imidizing the obtained solution to obtain the soluble polyimide resin powder with low thermal expansion coefficient. The polyimide resin powder can be dissolved in polar solvents such as DMAc, NMP, toluene, cyclohexanone and the like, has a low thermal expansion coefficient, is close to a metal copper foil, and has a more valuable application prospect in electronic components.

Description

A kind of low thermal expansion coefficient soluble polyimide resin powder and preparation method thereof

technical field

The invention relates to polyimide materials, in particular to a low thermal expansion coefficient soluble polyimide resin powder and a preparation method thereof.

Background technique

Polyimide (PI) is widely used in the field of electronic and electrical industry due to its excellent high temperature resistance, mechanical properties and chemical resistance properties, but its inherent insoluble and infusible properties make it difficult to process and form. The scope of application is limited. So far, many literatures have reported that the processing temperature of polyimide can be reduced to 370 °C by introducing flexible segments, twisted segments, and aliphatic segments into the molecular structure of polyimide. It can be processed, but the conditions are still very harsh. During the processing of block shaped products, the difference between the size of the product and the standard part, and the presence of air bubbles in the interior are prone to occur, resulting in a very low yield of the finished product. On the other hand, most domestic molding processing manufacturers use traditional processing equipment, which is mainly used to process low-temperature processable resins such as polyolefin and epoxy. Hot forming.

Soluble polyimide resin is a kind of high-strength and high-strength resin that can be dissolved in polar solvents (such as dimethylacetamide or dimethylpyrrolidone, etc.), then formed by coating or brushing, and then dried at low temperature. Heat-resistant materials can be used in packaging, sealing, encapsulation, etc. The design idea of soluble polyimide is to reduce the free bulk density of polyimide by introducing alicyclic structure, asymmetric structure, flexible group, aliphatic chain, etc. into the main chain of polyimide molecule. Improve the solubility of polyimide, but sacrifice its heat resistance and dimensional stability. For example, the invention patent with publication number CN103724623A proposes a soluble and fusible polyimide molding powder, whose glass transition temperature Tg is 289-294°C and tensile strength is 114-120MPa, although it is not mentioned in the text Its coefficient of thermal expansion (CTE), but the monomers used by those skilled in the art mainly include 2,3,3',4'-diphenyl ether tetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether, more Too many flexible groups of ether bonds make the molecular chain relatively soft, resulting in insufficient rigidity and high CTE. The invention patent with publication number CN102369233A proposes a combination of cyclohexanediamine and other diamines (norbornene diamine) as the diamine component of polyimide to achieve low thermal expansion coefficient and high light transmittance. and high UV transmittance characteristics of polyimide resin. Although the CTE of the polyimide resin described in the invention is as low as 14ppm/K (the value range is 100-200°C), the cyclohexanediamine used is expensive and the cost is high; It can be known from the monomers used by the personnel that the polyimide resin obtained by it is insoluble or insoluble in aprotic polar solvents or other organic solvents (such as toluene, cyclohexanone, etc.). Amine resin powder has lower CTE and better processability at the same time, which is a technical difficulty at present.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a low thermal expansion coefficient polyimide resin powder for the problems of insufficient processability and insufficient rigidity of the soluble polyimide polyimide in the existing low thermal expansion coefficient polyimide resin. and preparation method thereof

In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions:

A low thermal expansion coefficient soluble polyimide resin powder, the molecular structure of which is shown in the following formula (A):

in:

The molar ratio of diamine group and dianhydride group in formula (A) is 1:1;

Ar1 represents any one of the following formulae (Ar1-1) to (Ar1-8) and their isomers:

Ar2 represents any one of the following formulae (Ar2-1) to (Ar2-10) and their isomers:

D represents a rigid straight chain block, and the proportion of the block in the total molecular structure represented by the formula (A) is 15-60 mol%, and the block is composed of the repeating structural unit represented by the following formula (B):

其中，

in,

a=2～20;

Ar3 represents any one of the following formulae (Ar3-1) to (Ar3-5) and their isomers:

The low thermal expansion coefficient soluble polyimide resin powder of the present invention can be dissolved in aprotic polar solvents (such as N,N-dimethylformamide, N,N-dimethylacetamide) without heating , N,N-diethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, etc.), soluble in toluene under heating conditions , cyclohexanone and other solvents. The dissolving amount of the low thermal expansion coefficient soluble polyimide resin powder of the present invention is more than 1/10 g, including heating measures.

The present invention also provides a method for preparing the above-mentioned low thermal expansion coefficient soluble polyimide resin powder, including the steps of preparing a low thermal expansion coefficient soluble polyamic acid resin solution and preparing the low thermal expansion coefficient soluble polyamic acid resin solution from the low thermal expansion coefficient soluble polyamic acid resin solution. The step of imine resin powder, wherein, the step of preparing low thermal expansion coefficient soluble polyamic acid resin solution comprises:

The first step: react 4,4'-diamino-2,2'-bistrifluoromethyl biphenyl (TFDB) with a dianhydride monomer whose main structure is Ar3 in an aprotic polar solvent to obtain Block polyamic acid resin solution; wherein,

Ar3 represents any one of the following formulae (Ar3-1) to (Ar3-5) and their isomers:

The second step: add the diamine monomer and aprotic polar solvent whose main structure is the structure shown by Ar1 to the obtained block polyamic acid resin solution, and then add the dianhydride monomer whose main structure is the structure shown by Ar2 in batches body reaction to obtain a low thermal expansion coefficient soluble polyamic acid resin solution; wherein,

The addition amount of the diamine monomer whose main structure is the structure represented by Ar1 and the dianhydride monomer whose main structure is the structure represented by Ar2 is to control the proportion of the block polyamic acid resin in the obtained low thermal expansion coefficient soluble polyamic acid resin. The ratio is 15-60 mol%, and the added dianhydride monomer with the main structure of Ar2 and the diamine monomer with the main structure of Ar1 makes the obtained low thermal expansion coefficient soluble polyamic acid resin. The molar ratio of amine groups and dianhydride groups is 1:1;

Ar1 represents any one of the following formulae (Ar1-1) to (Ar1-8) and their isomers:

Ar2 represents any one of the following formulae (Ar2-1) to (Ar2-10) and their isomers:

The invention reduces the conjugation effect between molecules by introducing fluorine side groups into the molecular structure of polyimide, increases the spacing of polyimide molecular chains, reduces the force between molecular chains, and destroys the tight stacking of molecular chains. Make its free volume larger, which is beneficial for solvent molecules to enter the polyimide resin system to swell until dissolved, thereby improving the solvent solubility of the obtained polyimide resin; while the introduction of rigid aromatic dianhydride monomers and electron-withdrawing monomers The rigid straight-chain block composed of the fluorine pendant diamine with strong property is controlled, and the number of repeating structural units of the block and the proportion of the block are controlled, so that the obtained soluble polyimide resin maintains a low thermal expansion coefficient.

In the first step of the above step of preparing the low thermal expansion coefficient soluble polyamic acid resin solution, the amount of the aprotic polar solvent is usually controlled to control the solid content of the block polyamic acid resin in the obtained block polyamic acid resin solution to be 10～ 25%, preferably 10-15%; TFDB in the system is in excess relative to the dianhydride monomer whose main structure is the structure represented by Ar3, and the dianhydride monomer whose main structure is the structure represented by Ar3 can be selected from homobenzene. Tetracarboxylic dianhydride (PMDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride and 2,3,3'4'-biphenyltetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride (BTDA), any one of 1,4,5,8-naphthalenetetracarboxylic anhydride (NTCDA) and cyclohexanetetracarboxylic dianhydride (HPMDA). In this step, the number of repeating structural units in the obtained block polyamic acid resin solution is preferably 2-20.

In the second step of the above step of preparing the low thermal expansion coefficient soluble polyamic acid resin solution, the amount of the aprotic polar solvent is usually controlled to control the solidity of the low thermal expansion coefficient soluble polyamic acid resin in the obtained low thermal expansion coefficient soluble polyamic acid resin solution. The content is 10-25%, preferably 10-15%; the diamine monomer whose main structure is the structure represented by Ar1 can be specifically selected from 3,4-diaminodiphenyl ether (3,4-ODA), 3,3'diaminodiphenyl ether (3,3-ODA), 4,4-diaminodiphenyl ether (4,4-ODA), 2,2-bis[4-(4-aminophenoxy) ) phenyl] propane (BAPP), all-meta-triphenylenediether diamine, 1,3-bis(4-aminophenoxy)benzene (TPER), 3,5-diamino4'benzynyldiphenylmethane Ketone, N,N'-diphenylbenzidine, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenyldifluoromethane, 2,2-bis(4-amino Benzene)-propane, bis(4-(3-aminophenoxy)phenyl)sulfide (BAS), 4,4'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide Ether and any one of bis(4-(3-aminophenoxy)phenyl)sulfone, 1,6-hexanediamine, 1,9-nonanediamine and 1,10-diaminodecane; all The dianhydride monomer whose main structure is the structure represented by Ar2 is specifically selected from 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA), 2,3,3'4' -Biphenyltetracarboxylic dianhydride (a-BPDA), 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride (OBDP), butane tetracarboxylic dianhydride, cyclohexane tetracarboxylic dianhydride anhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride (ODPA), 4,4-hexafluoroisopropyl phthalic anhydride (6FDA), benzophenone tetracarboxylic dianhydride ( Any one of BTDA), bisphenol A type diether dianhydride (BPADA) and triphenyl bisether dianhydride.

The step of preparing the low thermal expansion coefficient soluble polyimide resin powder from the low thermal expansion coefficient soluble polyamic acid resin solution described in the above preparation method is: chemically imidizing the low thermal expansion coefficient soluble polyamic acid resin solution or thermally. The imidization method is carried out to obtain a low thermal expansion coefficient soluble polyimide resin powder; wherein the imidization is carried out under the condition of ≤250°C. More preferably, the imidization can be completed under the condition of ≤200°C. specific:

When the imidization is carried out by chemical imidization, the step of preparing the low thermal expansion coefficient soluble polyimide resin powder from the low thermal expansion coefficient soluble polyamic acid resin solution is as follows: Put it in a reaction vessel, drop amine catalyst, dehydrating agent and xylene into it, control the solid content of the low thermal expansion coefficient soluble polyamic acid resin in the obtained system to be 5-10%, and then react under heating or non-heating conditions, After the reaction is completed, cool, transfer the reaction material into a poor solvent, filter, wash, and imidize the filter cake under the condition of vacuum and temperature≤250℃ to obtain low thermal expansion coefficient soluble polyimide resin powder.

When the above chemical imidization is adopted, the reaction is usually carried out at 30-150 °C, and the reaction time is preferably 1-12 h; when the imidization temperature is 200 °C, the time is preferably controlled at 10-12 h. The amine catalyst and dehydrating agent involved and their additions are conventional selections in the prior art, preferably, the amine catalyst can be any one of triethylamine, pyridine, lutidine and isoquinoline one or a combination of two; the dehydrating agent can be acetic anhydride and/or propionic anhydride. The molar equivalent ratio of dianhydride:catalyst:dehydrating agent is 1:1:1.5, and the amount of dehydrating agent added is usually 1-2 times the molar amount of the catalyst, preferably 1.5 times.

When the imidization is carried out by thermal imidization, the step of preparing the low thermal expansion coefficient soluble polyimide resin powder from the low thermal expansion coefficient soluble polyamic acid resin solution is as follows: Place in the reaction vessel, add xylene to it, control the solid content of the low thermal expansion coefficient soluble polyamic acid resin in the obtained system to be 5-10%, then react under heating conditions, after the reaction is completed, cool, and transfer the reaction material into In a poor solvent, wash, filter, and imidize the filter cake under the conditions of vacuum and temperature ≤ 250 ℃ to obtain low thermal expansion coefficient soluble polyimide resin powder.

When the above thermal imidization is adopted, the reaction is usually carried out at the reflux temperature of the solvent, and the reaction time is usually 1-12 h; when the imidization temperature is 200° C., the time is preferably controlled at 10-12 h. The inferior solvents involved in the above two imidization methods are the same as those in the prior art, and can specifically be any one or a combination of two or more selected from acetone, methanol and ethanol.

The aprotic polar solvent involved in the method of the present invention is the same as the prior art, and can be specifically selected from N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, Any one or a combination of N-methylpyrrolidone and γ-butyrolactone, etc.

The present invention also includes the low thermal expansion coefficient soluble polyimide resin powder prepared by the above method.

The low thermal expansion coefficient soluble polyimide resin powder of the present invention can be dissolved in aprotic polar solvents to be further prepared into polyimide glue, polyimide film or polyimide varnish, and heat treatment to obtain high performance Thin film material or insulating paint film. The obtained thin film can be applied to the passivation protective film of semiconductor chips, the buffer inner coating film of electronic devices, the protective film of solder joints and the interlayer insulating film of the multi-layer metal interconnection structure.

Specifically, the method for preparing the low thermal expansion coefficient soluble polyimide resin powder of the present invention into a low thermal expansion coefficient soluble polyimide film is as follows: dissolving the obtained low thermal expansion coefficient soluble polyimide resin powder in an aprotic electrode A resin solution with a certain viscosity is obtained in a neutral solvent, which is coated on a clear glass plate after defoaming, and imidized according to the procedure from low temperature to high temperature (such as 80°C/1h+130°C/0.5h+180°C). /0.5h+200℃/0.5h degree of imidization), the low thermal expansion coefficient soluble polyimide film can be obtained.

Compared with the prior art, the characteristics of the present invention are:

1. By introducing fluorine side groups into the molecular structure of polyimide, the conjugation effect between molecules is reduced, the distance between polymer molecular chains is increased, the force between molecular chains is reduced, and the close stacking of molecular chains is destroyed, so that the The free volume becomes larger, which is beneficial for the solvent molecules to enter the polyimide resin system and swell until dissolved, thereby improving the solvent solubility of the obtained polyimide resin; while the introduction of rigid aromatic dianhydride monomers and relatively electron-absorbing properties The rigid straight-chain block composed of strong fluorine pendant diamine, and the number of repeating structural units and the proportion of the block are controlled, so that the obtained soluble polyimide resin maintains a good thermal expansion coefficient; in addition, from the rigid segment Starting from the compatibility problem with the flexible segment, by utilizing the complementarity and synergy between different polymers, by copolymerizing the rigid block polymer with the flexible block polymer, it is possible to improve the soluble polymer without forming a large number of crystals. Processability of imide resins. Therefore, the polyimide resin powder prepared by the method of the present invention can be dissolved in polar solvents such as DMAc, NMP, toluene and cyclohexanone, and has a low thermal expansion coefficient, which is close to that of metal copper foil. The device has more valuable application prospects.

2. The polyimide film prepared by using the low thermal expansion coefficient soluble polyimide resin powder of the present invention according to the conventional method has a low thermal expansion coefficient, which can be as low as 16.1ppm/K.

Detailed ways

The present invention will be described in further detail below in conjunction with specific embodiments to better understand the content of the present invention, but the present invention is not limited to the following embodiments.

The parts described in the following examples are parts by weight.

Example 1

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 27.293 parts of TFDB and 250 parts of aprotic polar solvent N,N-dimethylformamide and put them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 12.394 parts of PMDA monomer, The reaction was stirred for 2h to obtain a block polyamic acid resin solution for subsequent use; wherein, in the system, TFDB was excessive relative to the PMDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution was 2;

The second step: add 39.81 parts of 3,4-ODA and 600 parts of aprotic polar solvent N,N-dimethylformamide to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, and then add 70.503 ODPA monomer (added in 3 times), stirred and reacted for 4 hours to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 08,000 mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, the proportion of block polyamic acid resin in the system is 20mol%, and the solid content is 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

The obtained low thermal expansion coefficient soluble polyamic acid resin solution was placed in a three-necked flask, then a dropping funnel was assembled, and under stirring, the mixed liquid of 22.95 parts of pyridine, 44.43 parts of acetic anhydride and 500 parts of xylene was slowly added dropwise. After the dropping, the dropping funnel was removed, and the solid content of the low thermal expansion coefficient soluble polyamic acid resin in the obtained system was 10%; then the three-necked flask was placed on the heating mantle, and the temperature was slowly raised to 150 ° C and kept for 1 h, and then cooled to room temperature; slowly pour the reaction material into ethanol, stir, filter under reduced pressure, wash twice with water, and then complete imidization under vacuum at 200°C/12h to obtain low thermal expansion coefficient soluble polyimide resin powder. The solubility of the obtained resin powder in the organic solvent is shown in Table 1.

Take 10 parts of the low thermal expansion coefficient soluble polyimide resin powder obtained in this example and dissolve it in 90 parts of N,N-dimethylformamide to obtain a transparent and uniform resin solution after defoaming, and then coat it on a smooth Place it on a flat plate, place it in a blast drying oven, and carry out imidization according to the procedure of 80°C/1h+130°C/0.5h+180°C/0.5h+200°C/0.5h to obtain a low thermal expansion coefficient soluble polyimide Amine film. The thermal expansion coefficient CTE results of the obtained films are shown in Table 1.

Example 2

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 59.901 parts of TFDB and 250 parts of aprotic polar solvent DMAc and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 34.0 parts of PMDA monomer, and stir for 2h to obtain a block polymer. The amic acid resin solution is for subsequent use; wherein, in the system, TFDB is excessive relative to the PMDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution is 5;

The second step: add 24.963 parts of 3,4-ODA and 550 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 81.135 parts of BPADA monomer (divided into 3 times) Add), stirring and reacting for 4 hours to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 12,000 mpa s; the molar ratio of diamine monomer and dianhydride monomer in the whole system is 1:1, and the block polyamide The proportion of acid resin in the system is 50mol%, and the solid content is 20%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

The obtained low thermal expansion coefficient soluble polyamic acid resin solution was placed in a three-necked flask, then a dropping funnel was assembled, and under stirring, a mixture of 20.114 parts of lutidine, 33.12 parts of acetic anhydride and 250 parts of xylene was slowly added dropwise. After dropping the liquid, remove the dropping funnel, and the solid content of the low thermal expansion coefficient soluble polyamic acid resin in the obtained system is 16%; then place the three-necked flask on the heating mantle, slowly heat up to 30 ° C and keep the reaction for 12 h, Then cooled to room temperature; slowly poured the reaction material into ethanol, stirred, filtered under reduced pressure, washed twice with water, and then completely imidized under vacuum at 200°C/12h to obtain a low thermal expansion coefficient soluble polyimide resin pink. The solubility of the obtained resin powder in the organic solvent is shown in Table 1.

Take 10 parts of the low thermal expansion coefficient soluble polyimide resin powder obtained in this example and dissolve it in 90 parts of DMAc. After defoaming, a transparent and uniform resin solution is obtained, which is then coated on a smooth flat plate and placed in blast drying. In the box, the imidization was carried out according to the procedure of 80°C/1h+130°C/0.5h+180°C/0.5h+200°C/0.5h to obtain a low thermal expansion coefficient soluble polyimide film. The thermal expansion coefficient CTE of the obtained film was tested, and the results are shown in Table 1.

Example 3

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 13.702 parts of TFDB and 250 parts of aprotic polar solvent NMP and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 8.711 parts of PMDA monomer, and stir for 2 hours to obtain a block polyamide Acid resin solution, standby; Wherein, in the system, TFDB is excessive relative to PMDA monomer, and the number of repeating structural units in the gained block polyamic acid resin solution is 12;

The second step: add 48.538 parts of 3,4-ODA and 600 parts of aprotic polar solvent NMP to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, and then add 79.049 parts of BTDA monomer (in 3 times Add), stirring and reacting for 4 hours to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 12,000 mpa s; the molar ratio of diamine monomer and dianhydride monomer in the whole system is 1:1, and the block polyamide The proportion of acid resin in the system is 14mol%, and the solid content is 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

The obtained low thermal expansion coefficient soluble polyamic acid resin solution was placed in a three-necked flask, then a dropping funnel was assembled, and under stirring, the mixed liquid of 40.565 parts of triethylamine, 61.388 parts of acetic anhydride and 875 parts of xylene was slowly added dropwise. , remove the dropping funnel after the dropping, the solid content of the low thermal expansion coefficient soluble polyamic acid resin in the obtained system is 8%; then place the three-necked flask on the heating mantle, slowly heat up to 120 ° C and keep the reaction for 2 h, then Cool to room temperature; slowly pour the reaction material into ethanol, stir, filter under reduced pressure, wash twice with water, and then complete imidization under vacuum at 200°C/12h to obtain low thermal expansion coefficient soluble polyimide resin powder . The solubility of the obtained resin powder in the organic solvent is shown in Table 1.

Take 10 parts of the low thermal expansion coefficient soluble polyimide resin powder obtained in this example and dissolve it in 90 parts of NMP to obtain a transparent and uniform resin solution after defoaming, which is then coated on a smooth flat plate and placed in blast drying In the box, the imidization was carried out according to the procedure of 80°C/1h+130°C/0.5h+180°C/0.5h+200°C/0.5h to obtain a low thermal expansion coefficient soluble polyimide film. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Example 4

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 23.523 parts of TFDB and 250 parts of aprotic polar solvent N,N-dimethylacetamide and put them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 16.023 parts of PMDA monomer, The reaction was stirred for 2h to obtain a block polyamic acid resin solution for subsequent use; wherein, TFDB in the system was excessive relative to the PMDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution was 20;

The second step: add 34.311 parts of 3,4-ODA and 600 parts of aprotic polar solvent DMAC to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 76.143 parts of 6FDA monomer (in 3 times Add), stirring and reacting for 4h to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 15,000 mpa s; the molar ratio of diamine monomer and dianhydride monomer in the whole system is 1:1, and the block polyamide The proportion of acid resin in the system is 30mol%, and the solid content is 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

The obtained low thermal expansion coefficient soluble polyamic acid resin solution was placed in a three-necked flask, then a dropping funnel was assembled, and under stirring, the mixed liquid of 19.368 parts of pyridine, 37.496 parts of acetic anhydride and 500 parts of xylene was slowly added dropwise. After the dropping, the dropping funnel was removed, and the solid content of the low thermal expansion coefficient soluble polyamic acid resin in the obtained system was 10%; then the three-necked flask was placed on the heating mantle, slowly heated to 80 ° C and kept for 10 h, and then cooled to room temperature; slowly pour the reaction material into ethanol, stir, filter under reduced pressure, wash twice with water, and then complete imidization under vacuum at 200°C/12h to obtain low thermal expansion coefficient soluble polyimide resin powder. The solubility of the obtained resin powder in the organic solvent is shown in Table 1.

Take 10 parts of the low thermal expansion coefficient soluble polyimide resin powder obtained in this example and dissolve it in 90 parts of NMP to obtain a transparent and uniform resin solution after defoaming, which is then coated on a smooth flat plate and placed in blast drying In the box, the imidization was carried out according to the procedure of 80°C/1h+130°C/0.5h+180°C/0.5h+200°C/0.5h to obtain a low thermal expansion coefficient soluble polyimide film. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Example 5

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 35.891 parts of TFDB and 250 parts of aprotic polar solvent DMAc and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 26.38 parts of BPDA monomer, and stir and react for 2h to obtain a block polymer. The amic acid resin solution is for subsequent use; wherein, in the system, TFDB is excessive relative to the BPDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution is 5;

The second step: add 46.0018 parts of BAPP and 547 parts of aprotic polar solvent DMAC to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 41.72 parts of ODPA monomer (add in 3 times), stir The reaction was carried out for 4 h to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 10,000 mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid resin was in the system. The proportion of 50mol%, the solid content of 18.8%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

The obtained low thermal expansion coefficient soluble polyamic acid resin solution was placed in a three-necked flask, then a dropping funnel was assembled, and under stirring, the mixed liquid of 28.475 parts of isoquinoline, 43.037 parts of propionic anhydride and 500 parts of xylene was slowly added dropwise. , remove the dropping funnel after the dripping, the solid content of the low thermal expansion coefficient soluble polyamic acid resin in the obtained system is 11.5%; then place the three-necked flask on the heating mantle, slowly heat up to 120 ° C and keep the reaction for 3 hours, then Cool to room temperature; slowly pour the reaction material into ethanol, stir, filter under reduced pressure, wash twice with water, and then complete imidization under vacuum at 200°C/12h to obtain low thermal expansion coefficient soluble polyimide resin powder . The solubility of the obtained resin powder in the organic solvent is shown in Table 1.

Take 10 parts of the low thermal expansion coefficient soluble polyimide resin powder obtained in this example and dissolve it in 90 parts of NMP to obtain a transparent and uniform resin solution after defoaming, which is then coated on a smooth flat plate and placed in blast drying In the box, the imidization was carried out according to the procedure of 80°C/1h+130°C/0.5h+180°C/0.5h+200°C/0.5h to obtain a low thermal expansion coefficient soluble polyimide film. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Example 6

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 35.508 parts of TFDB and 250 parts of aprotic polar solvent DMAc and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 26.099 parts of BPDA monomer, and stir for 2h to obtain a block polymer. The amic acid resin solution, with a viscosity of 21,000 mPa·s, is ready for use; wherein, the TFDB in the system is excessive relative to the BPDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution is 5;

The second step: add 45.518 parts of BAPP and 600 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 42.875 parts of BTDA monomer (add in 3 times), stir After 4 hours of reaction, a low thermal expansion coefficient soluble polyamic acid resin solution was obtained, with a viscosity of 12,000 mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid resin was in the system. The proportion of 50mol%, the solid content of 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

The obtained low thermal expansion coefficient soluble polyamic acid resin solution was placed in a three-necked flask, then a dropping funnel was assembled, 500 parts of xylene were added, and the reaction was conducted under reflux for 12 hours, and then cooled to room temperature; the reaction material was slowly poured into ethanol, Stirring, filtering under reduced pressure, washing with acetone for 5 times, and then complete imidization under vacuum conditions at 200° C./12h to obtain low thermal expansion coefficient soluble polyimide resin powder. The solubility of the obtained resin powder in the organic solvent is shown in Table 1.

The low thermal expansion coefficient soluble polyimide resin powder obtained in this example is used to prepare a low thermal expansion coefficient soluble polyimide film according to the process described in Example 5. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Example 7

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 32.04 parts of TFDB and 250 parts of aprotic polar solvent DMAc and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 23.55 parts of BPDA monomer, and stir for 2h to obtain a block polymer. The amic acid resin solution, with a viscosity of 23,000 mpa s, is ready for use; wherein, the TFDB in the system is excessive relative to the BPDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution is 5;

The second step: add 41.073 parts of BAPP and 600 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 53.337 parts of 6FDA monomer (add in 3 times), stir After 6 hours of reaction, a low thermal expansion coefficient soluble polyamic acid resin solution was obtained with a viscosity of 08,000 mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid resin was in the system. The proportion of 50mol%, the solid content of 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

Same as Example 6.

Table 1 shows the solubility of the obtained low thermal expansion coefficient soluble polyimide resin powder in an organic solvent.

The low thermal expansion coefficient soluble polyimide resin powder obtained in this example is used to prepare a low thermal expansion coefficient soluble polyimide film according to the process described in Example 5. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Example 8

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 33.874 parts of TFDB and 250 parts of aprotic polar solvent DMAc and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 26.844 parts of BTDA monomer, and stir for 1 h to obtain a block polymer. An amic acid resin solution, for subsequent use; wherein, in the system, TFDB is excessive relative to BTDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution is 5;

The second step: add 45.749 parts of BAS and 600 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 44.772 parts of OBDP monomer (add in 2 times), stir The reaction was carried out for 3 hours to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 0.6 million mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid resin was in the system. The proportion of 50mol%, the solid content of 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

Same as Example 6.

Table 1 shows the solubility of the obtained low thermal expansion coefficient soluble polyimide resin powder in an organic solvent.

The low thermal expansion coefficient soluble polyimide resin powder obtained in this example is used to prepare a low thermal expansion coefficient soluble polyimide film according to the process described in Example 5. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Example 9

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 32.621 parts of TFDB and 250 parts of aprotic polar solvent DMAc and put them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 25.865 parts of BTDA monomer, and stir for 1 h to obtain a block polymer. An amic acid resin solution, for subsequent use; wherein, in the system, TFDB is excessive relative to BTDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution is 5;

The second step: add 29.779 parts of TPER and 600 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 62.671 parts of BPADA monomer (add in 3 times), stir The reaction was carried out for 3 hours to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 12,000 mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid resin was in the system. The proportion of 50mol%, the solid content of 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

Same as Example 6.

Table 1 shows the solubility of the obtained low thermal expansion coefficient soluble polyimide resin powder in an organic solvent.

The low-thermal-expansion-coefficient-soluble polyimide resin powder obtained in this example was used to prepare a low-thermal-expansion-coefficient-soluble polyimide film according to the process described in Example 5. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Example 10

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 39.765 parts of TFDB and 250 parts of aprotic polar solvent DMAc and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 32.10 parts of BTDA monomer, and stir for 1 h to obtain a block polymer. An amic acid resin solution, for subsequent use; wherein, in the system, TFDB is excessive relative to BTDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution is 5;

The second step: add 24.835 parts of ODA and 600 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 54.397 parts of OBDP monomer (add in 3 times), stir The reaction was carried out for 3 hours to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 0.9 million mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid resin was in the system. The proportion of 50mol%, the solid content of 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

Same as Example 6.

Table 1 shows the solubility of the obtained low thermal expansion coefficient soluble polyimide resin powder in an organic solvent.

The low thermal expansion coefficient soluble polyimide resin powder obtained in this example is used to prepare a low thermal expansion coefficient soluble polyimide film according to the process described in Example 5. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Example 11

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 33.088 parts of TFDB and 250 parts of aprotic polar solvent DMAc and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 22.168 parts of NTCDA monomer, and stir for 1 h to obtain a block polymer. The amic acid resin solution is for subsequent use; wherein, in the system, TFDB is excessive relative to the NTCDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution is 5;

The second step: add 30.205 parts of TPEQ and 600 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 64.537 parts of BPADA monomer (add in 3 times), stir Reaction for 3h to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 0.5 million mpa s; the molar ratio of diamine monomer and dianhydride monomer in the whole system is 1:1, and the block polyamic acid resin is in the system. The proportion of 50mol%, the solid content of 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

Same as Example 6.

Table 1 shows the solubility of the obtained low thermal expansion coefficient soluble polyimide resin powder in an organic solvent.

The low thermal expansion coefficient soluble polyimide resin powder obtained in this example is used to prepare a low thermal expansion coefficient soluble polyimide film according to the process described in Example 5. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Comparative Example 1

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: get 31.543 parts of ODA and 250 parts of solvent N,N-dimethylacetamide and place them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 28.258 parts of cyclohexanetetracarboxylic dianhydride ( HPMDA) monomer, stirred and reacted for 2h to obtain a block polyamic acid resin solution, for subsequent use; wherein, the diamine in the system was excessive relative to the HPMDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution was 5;

The second step: add 31.543 parts of 3,4-ODA and 600 aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 58.655 parts of ODPA monomer (add in 3 times ), stirred and reacted for 4 h to obtain a low thermal expansion coefficient soluble polyamic acid resin solution with a viscosity of 0.9 million mpa s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid The proportion of resin in the system is 50mol%, and the solid content is 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

Same as Example 6.

Table 1 shows the solubility of the obtained low thermal expansion coefficient soluble polyimide resin powder in an organic solvent.

The low-thermal-expansion-coefficient-soluble polyimide resin powder obtained in this example was used to prepare a low-thermal-expansion-coefficient-soluble polyimide film according to the process described in Example 1. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Comparative Example 2

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

The first step: take 26.596 parts of PBI and 250 parts of solvent N,N-dimethylacetamide, put them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 30.572 parts of BPDA monomer, and stir and react for 2h, Obtain block polyamic acid resin solution, standby; Wherein, in the system, diamine is excessive with respect to BPDA monomer, and the number of repeating structural units in the gained block polyamic acid resin solution is 5;

The second step: add 48.685 parts of BAPP and 600 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 44.146 parts of ODPA monomer (add in 3 times), stir After 4 hours of reaction, a low thermal expansion coefficient soluble polyamic acid resin solution was obtained, with a viscosity of 12,000 mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid resin was in the system. The proportion of 50mol%, the solid content of 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

Same as Example 6.

Table 1 shows the solubility of the obtained low thermal expansion coefficient soluble polyimide resin powder in an organic solvent.

The low thermal expansion coefficient soluble polyimide resin powder obtained in this example is used to prepare a low thermal expansion coefficient soluble polyimide film according to the process described in Example 5. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Comparative Example 3

The specific preparation method is:

1) The steps of preparing the low thermal expansion coefficient soluble polyamic acid resin solution:

Step 1: Take 24.34 parts of 3,4-ODA and 250 parts of solvent N,N-dimethylacetamide and put them in a three-necked flask with an electric stirrer, stir until completely dissolved, add 28.644 parts of BPDA monomer, The reaction was stirred for 2h to obtain a block polyamic acid resin solution with a viscosity of 08,000 mPa·s, which was used for subsequent use; wherein, the diamine in the system was excessive relative to the BPDA monomer, and the number of repeating structural units in the obtained block polyamic acid resin solution was is 5;

The second step: add 49.958 parts of BAPP and 600 parts of aprotic polar solvent DMAc to the obtained block polyamic acid resin solution, stir until the monomer is completely dissolved, then add 47.057 parts of BTDA monomer (add in 3 times), stir After 4 hours of reaction, a low thermal expansion coefficient soluble polyamic acid resin solution was obtained, with a viscosity of 2.6 mpa·s; the molar ratio of diamine monomer and dianhydride monomer in the whole system was 1:1, and the block polyamic acid resin was in the system. The proportion is 40mol%, and the solid content is 15%;

2) The steps of preparing low thermal expansion coefficient soluble polyimide resin powder from low thermal expansion coefficient soluble polyamic acid resin solution:

Same as Example 6.

Table 1 shows the solubility of the obtained low thermal expansion coefficient soluble polyimide resin powder in an organic solvent.

The low-thermal-expansion-coefficient-soluble polyimide resin powder obtained in this example was used to prepare a low-thermal-expansion-coefficient-soluble polyimide film according to the process described in Example 1. The thermal expansion coefficient and other properties of the obtained films were tested, and the results are shown in Table 1.

Table 1:

Note: - means soluble by heating, -- means soluble, ○ is insoluble; the thermal expansion coefficient ranges from 100 to 200°C, and a is the number of repeating structural units in the block polyamic acid resin solution.

Comparing Examples 1 to 11 and Comparative Example 1, the polyimide resin powder prepared by HPMDA with a six-membered ring structure is soluble, but its heat resistance is insufficient, and the CTE is 46.4 in the range of 100 to 200 ° C. ppm/K; Comparative Example 2 uses PBI with a hybrid structure, which has a low CTE value and insufficient solubility; Comparative Example 3 is compared with Example 6, and it is found that replacing TFDB with ODA not only reduces the solubility, but also increases the CTE value.

Claims (9)

1. A soluble polyimide resin powder with low thermal expansion coefficient has a molecular structure shown as the following formula (A):

wherein:

the molar ratio of diamine groups to dianhydride groups in formula (a) is 1: 1;

ar1 represents any one of the following formulae (Ar1-1) to (Ar1-8) and isomers thereof:

ar2 represents any one of the following formulae (Ar2-1) to (Ar2-10) and isomers thereof:

d represents a rigid linear block, the proportion of the block in the total molecular structure represented by the formula (A) is 15 to 60 mol%, and the block is composed of a repeating structural unit represented by the following formula (B):

wherein,

a＝2～20；

ar3 represents any one of the following formulae (Ar3-1) to (Ar3-5) and isomers thereof:

2. the method for preparing a low cte soluble polyimide resin powder of claim 1, comprising the steps of preparing a low cte soluble polyamic acid resin solution and preparing a low cte soluble polyimide resin powder from the low cte soluble polyamic acid resin solution, wherein: the step of preparing the soluble polyamic acid resin solution with low thermal expansion coefficient includes:

the first step is as follows: reacting 4,4 '-diamino-2, 2' -bistrifluoromethylbiphenyl with a dianhydride monomer with a main structure of Ar3 in an aprotic polar solvent to obtain a block polyamic acid resin solution; wherein,

ar3 represents any one of the following formulae (Ar3-1) to (Ar3-5) and isomers thereof:

the second step is that: adding a diamine monomer with a main structure of Ar1 and an aprotic polar solvent into the obtained block polyamic acid resin solution, and then adding a dianhydride monomer with a main structure of Ar2 in batches for reaction to obtain a soluble polyamic acid resin solution with a low thermal expansion coefficient; wherein,

the adding amount of the diamine monomer with the main structure of Ar1 and the dianhydride monomer with the main structure of Ar2 is controlled to be 15-60 mol% of the block polyamic acid resin in the obtained low-thermal expansion coefficient soluble polyamic acid resin, and the adding amount of the dianhydride monomer with the main structure of Ar2 and the diamine monomer with the main structure of Ar1 enables the molar ratio of diamine groups and dianhydride groups in the obtained low-thermal expansion coefficient soluble polyamic acid resin to be 1: 1;

ar1 represents any one of the following formulae (Ar1-1) to (Ar1-8) and isomers thereof:

ar2 represents any one of the following formulae (Ar2-1) to (Ar2-10) and isomers thereof:

3. the method of claim 2, wherein: the dianhydride monomer with the main structure of Ar3 is selected from pyromellitic dianhydride (PMDA), 3,3',4,4' -biphenyl tetracarboxylic dianhydride, 2,3,3',4' -biphenyl tetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride and 1,4,5, 8-naphthalene tetracarboxylic dianhydride.

4. The method of claim 2, wherein: the diamine monomer with the main structure of Ar1 is selected from 3, 4-diaminodiphenyl ether, 3' diaminodiphenyl ether, 4-diaminodiphenyl ether, 2-bis [4- (4-aminophenoxy) phenyl ] propane, all-meta-triphenyldiethanediamine, 1, 3-bis (4-aminophenoxy) benzene, 3, 5-diamino 4' -phenylalkynylbenzophenone, N ' -diphenylbiphenyldiamine, 3' -diaminobenzophenone, 4' -diaminodiphenyldifluoromethane, 2-bis (4-aminophenyl) -propane, bis (4- (3-aminophenoxy) phenyl) sulfide, 4' -diaminodiphenylsulfide, 3, 4' -diaminodiphenylsulfide and bis (4- (3-aminophenoxy) phenyl) sulfone, 1, 6-hexanediamine, 1, 9-nonanediamine and 1, 10-diaminodecane.

5. The method of claim 2, wherein: the dianhydride monomer with the main structure of Ar2 is any one selected from 3,3',4,4' -biphenyl tetracarboxylic dianhydride, 2,3,3',4' -biphenyl tetracarboxylic dianhydride, 3,3',4,4' -diphenyl sulfone tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, cyclohexane tetracarboxylic dianhydride, 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride, 4, 4-hexafluoroisopropyl phthalic anhydride, benzophenone tetracarboxylic dianhydride, bisphenol A type diether dianhydride and triphenyl diether dianhydride.

6. The production method according to any one of claims 2 to 5, characterized in that: the preparation method of the low thermal expansion coefficient soluble polyimide resin powder from the low thermal expansion coefficient soluble polyamic acid resin solution comprises the following steps: imidizing the low-thermal expansion coefficient soluble polyamic acid resin solution in a chemical imidization mode or a thermal imidization mode to obtain low-thermal expansion coefficient soluble polyimide resin powder; wherein the imidization is carried out at a temperature of less than or equal to 250 ℃.

7. The method of claim 6, wherein: the imidization is carried out at the temperature of less than or equal to 200 ℃.

8. The method of claim 6, wherein: when imidization is carried out in a chemical imidization mode, the step of preparing the low-thermal expansion coefficient soluble polyimide resin powder from the low-thermal expansion coefficient soluble polyamic acid resin solution comprises the following steps:

placing the low-thermal-expansion-coefficient soluble polyamic acid resin solution into a reaction container, adding an amine catalyst, a dehydrating agent and xylene into the reaction container, controlling the solid content of the low-thermal-expansion-coefficient soluble polyamic acid resin in the obtained system to be 5-10%, then reacting under heating or non-heating conditions, cooling after the reaction is finished, transferring the reaction material into a poor solvent, filtering, and imidizing a filter cake under the conditions of vacuum and the temperature of less than or equal to 250 ℃ to obtain the low-thermal-expansion-coefficient soluble polyimide resin powder.

9. The method of claim 6, wherein: when imidization is carried out in a thermal imidization mode, the step of preparing the low-thermal expansion coefficient soluble polyimide resin powder from the low-thermal expansion coefficient soluble polyamic acid resin solution comprises the following steps:

placing the low-thermal-expansion-coefficient soluble polyamic acid resin solution into a reaction container, adding xylene into the reaction container, controlling the solid content of the low-thermal-expansion-coefficient soluble polyamic acid resin in the obtained system to be 5-10%, then reacting under a heating condition, cooling after the reaction is finished, transferring the reaction material into a poor solvent, filtering, and imidizing a filter cake under the conditions of vacuum and the temperature of less than or equal to 250 ℃ to obtain the low-thermal-expansion-coefficient soluble polyimide resin powder.