CN120137164A

CN120137164A - Low thermal expansion and recyclable polyimide resin and recycling method thereof

Info

Publication number: CN120137164A
Application number: CN202311703661.6A
Authority: CN
Inventors: 周鹤修; 林宥彤; 庄贵贻
Original assignee: Individual
Current assignee: Fanyan Technology Co ltd
Priority date: 2023-12-12
Filing date: 2023-12-12
Publication date: 2025-06-13

Abstract

The invention provides a polyimide resin with low thermal expansion and recycling, which has a recycling functional group and a rigid chemical structure, thus being easy to recycle and having good dimensional stability. Thus, the polyimide resin which has low thermal expansion and can be recycled has the characteristics of rigidity, chemical resistance and low thermal expansion and can be recycled, and a recycling method of the polyimide resin are provided.

Description

Low thermal expansion recyclable polyimide resin and recycling method thereof

Technical Field

The invention relates to a polyimide resin with low thermal expansion and recycling, and a preparation method thereof, in particular to a polyimide resin with the advantages of wide application temperature, chemical corrosion resistance, high strength, recycling and the like, which can be repaired and recycled by controlling the temperature, and a recycling method of the polyimide resin.

Background

Polymers can be classified into thermoplastic and thermosetting polymers according to their physical properties at elevated temperatures, thermosetting polymers being polymers that solidify after synthesis and do not soften when heated, and thermoplastic polymers, in contrast, thermoplastic polymers soften when heated after synthesis and solidify again when cooled. In addition, thermosetting polymers generally have better mechanical, thermal, and chemical properties and better dimensional stability than thermoplastic polymers, and are therefore widely used in applications requiring high temperature use, or requiring higher mechanical strength, or resistance to chemical corrosion, such as tires, circuit boards, and the like, and may also be referred to as thermosetting resins.

The thermosetting resin polymer can be applied in various fields, however, products made of the conventional thermosetting resin polymer cannot be repaired and can only be discarded after being broken or the life cycle is finished, so that the waste of resources is caused. In addition, since the waste thermosetting resin polymer is difficult to be naturally decomposed, it is currently only possible to dispose in a buried or incinerated manner, thus causing serious environmental pollution.

Polyimide resin is one kind of organic polymer material containing imide group and is prepared through polymerization of diamine and dianhydride, and high temperature cyclization and dewatering. Polyimide resin has excellent heat stability and good mechanical, electrical and chemical properties, and is widely applied to various fields. In recent years, related industries such as semiconductors, electronics and communication are vigorously developed in China, so that the economic development in China is driven, and the demands for chemicals and materials for electronics are increasingly increased. Polyimide resins, which have been used in applications such as high-temperature tapes, flexible circuit boards, optically sensitive polyimide insulating layers for IC packages, alignment films for LCDs, etc., have played an important role in electronic materials, particularly in the electronics industry where the requirements for materials are stringent, due to their superior properties.

In order to take usability into consideration, conventionally used polyimide resins are generally not easily recycled after being produced into products, and therefore, if the products are broken or the life cycle thereof is completed, the polyimide resin products can only be discarded. However, although there have been studies on repairable or recyclable polyimide resins, the polyimide resins have poor heat resistance and chemical resistance, which limits the application range of the products.

Therefore, it is an object of the present invention to provide a polyimide resin which has recyclability, has a certain heat resistance and chemical resistance after recycling, improves the durability of the product, can be recycled again, and is recycled to achieve the objective of zero waste emission.

In view of the above, it is a commercially valuable development goal to develop a polyimide resin that is rigid, resistant to chemical, heat resistant, recyclable, and yet has some resistance to heat and chemical after recycling.

Disclosure of Invention

The main object of the present invention is to provide a polyimide resin which is low in thermal expansion and recyclable, has rigidity, resistance to chemical transformation, heat resistance, recyclability, and has a certain heat resistance and resistance to chemical transformation after recycling.

Another object of the present invention is to provide a method for recycling polyimide resin with low thermal expansion, which can recycle polyimide resin in low temperature environment to achieve the goal of reducing resource waste and environmental pollution.

In view of the above-mentioned main object, the present invention provides a polyimide polymer resin with low thermal expansion and recycling, which comprises at least one unit represented by formula I:

And at least one dianhydride unit

Wherein a is selected from the group consisting of:

R is selected from the group consisting of:

R ₁ is selected from-CH ₃、-CH₂CH₃, or-CF ₃;

n is an integer greater than 1;

And the dianhydride unit is selected from the group consisting of:

1,2,4,5-cyclohexane tetracarboxylic dianhydride (1, 2,4,5-cyclohexanetetracarboxylic dianhydride), 3',4' -benzophenone tetracarboxylic dianhydride (3, 3',4' -benzophenonetetracarboxylic dianhydride), benzene tetracarboxylic dianhydride (pyromellitic dianhydride), 4'-oxydiphthalic anhydride (4, 4' -oxydiphthalic anhydride), bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic acid-2, 3,5,6-dianhydride (bicyclo [2.2.2] octane-2,3,5, 6-tetracarbonylic acid-2, 3,5, 6-dianhydride), dicyclohexyl-3,4,3',4' -tetracarboxylic acid dianhydride (dicyclohexyl-3, 4,3',4' -tetracarboxylic dianhydride), 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride (1, 2,3,4-cyclobutanetetracarboxylic dianhydride).

The present invention provides an embodiment wherein the low thermal expansion and recyclable polyimide polymer resin comprises units of the formula

And a compound of formula 1, wherein n is an integer greater than 1, formula 1 is about 80-95% mole ratio, formula 2 is about 5-20% mole ratio, and the compound of formula 1 is different from formula 2.

And a compound of formula 1, wherein n is an integer greater than 1, formula 1 is about 80-95% mole ratio, formula 3 is about 5-20% mole ratio, and the compound of formula 1 is different from formula 3.

In order to achieve another object, the present invention provides a method for recovering a polyimide resin having low thermal expansion and being recoverable, as described above, comprising:

Performing a dissolving step of dissolving the polyimide resin having low thermal expansion and being recyclable in a polar aprotic solvent to obtain a polyimide recycling solution, and

And performing a film forming step, namely performing coating and baking film forming by using the polyimide recovery solution to form a recovered polyimide film.

The invention provides an embodiment, wherein in the method for recycling the polyimide resin with low thermal expansion and recycling, the polar aprotic solvent is dimethylacetamide or N-methylpyrrolidone.

Drawings

FIG. 1 is a flow chart showing the steps of a method for recycling polyimide resin having low thermal expansion and being recyclable according to the present invention.

Detailed Description

For a further understanding and appreciation of the structural features and advantages achieved by the present invention, the following description is provided with reference to the preferred embodiments and in connection with the accompanying detailed description:

The invention provides a low thermal expansion and recoverable polyimide resin, which comprises at least one unit of the following formula:

and at least one dianhydride unit;

wherein a is selected from the group consisting of:

R is selected from the group consisting of:

R ₁ is selected from-CH ₃、-CH₂CH₃, or-CF ₃,

N is an integer greater than 1;

And the dianhydride unit is selected from the group consisting of 1,2,4,5-cyclohexane tetracarboxylic dianhydride (1, 2,4,5-cyclohexanetetracarboxylic dianhydride), 3',4' -benzophenone tetracarboxylic dianhydride (3, 3',4' -benzophenonetetracarboxylic dianhydride), benzene tetracarboxylic dianhydride (pyromellitic dianhydride), 4'-oxydiphthalic anhydride (4, 4' -oxydiphthalic anhydride), bicyclo [2.2.2] octane-2,3,5, 6-tetracarboxylic-2, 3,5,6-dianhydride (bicyclo [2.2.2] octane-2,3,5, 6-tetracarbonic-2, 3,5, 6-dicarbanilide), dicyclohexyl-3,4,3',4' -tetracarboxylic dianhydride (dicyclohexyl-3, 4,3',4' -tetracarboxylic dianhydride), and 1,2,3,4-cyclobutane tetracarboxylic dianhydride (1, 2,3,4-cyclobutanetetracarboxylic dianhydride).

In one embodiment of the present invention, the low thermal expansion and recyclable polyimide resin preferably comprises units of the formula

And a unit of formula 1 different from formula 2, wherein n is an integer greater than 1. When the polyimide resin is polymerized, the thermal expansion coefficient (coefficient of thermal expansion, CTE) and glass transition temperature (glass transformation temperature, tg) of the polyimide resin are optimal when the molar ratio of formula 1 is about 80 to 95% and the molar ratio of formula 2 is about 5 to 20%.

In another aspect of the invention, the low thermal expansion and recyclable polyimide resin preferably comprises units of the formula.

And a unit of formula 1 different from formula 3, wherein n is an integer greater than 1. When the polyimide resin is polymerized, the polyimide resin is preferably used at a thermal expansion coefficient and glass transition temperature of about 80 to 95% by mole of formula 1 and about 5 to 20% by mole of formula 3.

The polyimide resin of the present invention, which has low thermal expansion and is recyclable, can be recycled after use. Referring to FIG. 1, which is a schematic diagram illustrating steps of an embodiment of a recycling method according to the present invention, the recycling method comprises:

Step S10 of dissolving a polyimide resin which is low in thermal expansion and recoverable in a polar aprotic solvent to obtain a polyimide recovery solution, and

And step S20, coating and baking the polyimide recovery solution to form a recovered polyimide resin film.

When the method is used for recovering the polyimide resin which has low thermal expansion and can be recovered, the polyimide resin can be dissolved and recovered at a low temperature by using a solvent, and then the recovered polyimide resin solution is coated and baked to form a film, thereby forming a recovered polyimide resin film again. The polyimide resin after recovery has the same glass transition temperature and cleavage temperature (Decomposition temperature, td) as the polyimide resin before recovery, and the recovery rate is greater than 90%. In step S10, the solvent used for dissolving and recovering the polyimide resin having low thermal expansion may be a polar aprotic solvent (aprotic solvent), and preferably a solvent such as DMAc (dimethylacetamide), NMP (N-methylpyrrolidone) or the like is used.

The present invention will now be described in more detail with reference to the following examples, which are illustrative only and do not limit the scope of the invention.

Example 1 synthesis with imine monomers (AZ):

Into the reaction flask were charged 5.4g of 4-aminoacetophenone (0.4 mol), 2.0. 2.0g triethylamine (0.2 mol), 4.0 g of ethanol. Then heated to 80℃and after complete dissolution of the reactants in ethanol 2.7ghydrazine sulfate (0.2 mol) was added and reacted at reflux for 5 hours. Finally, the product was isolated by ice bath, filtered and washed with water and ethanol, the monomer structure of which is shown in formula 1-1 and the NMR spectrum of which is 1H NMR (400 MHz, d 6-DMSO): 7.6 (d, 4H), 6.30 (d, 2H), 2.29 (s, 6H).

Example 2 synthesis of monomer (AFZ) with imine:

Into the reaction flask were charged 0.5g (4-Aminophenyl) -2, 2-trifluoro-1-ethanone (0.5 mol), 0.8g triethylamine (2.5 mol), 1.4 g ethanol. Then heated to 90℃and after complete dissolution of the reactants in ethanol 0.17g hydrazine sulfate (0.5 mol) was added and reacted at reflux for 8 hours. Finally, the product was isolated by ice bath, filtered and washed with water and ethanol, the monomer structure of which is shown in formula 1-2 and the NMR spectrum of which is 1H NMR (400 MHz, d 6-DMSO): 7.7 (d, 4H), 6.6 (d, 4H).

Example 3 synthesis with imine monomer (IAF-1):

6.75g of 4' -Aminoacetophenone (0.05 mol), 6.5gp-PHENYLENEDIAMINE (0.06 mol) and 30 g of Toluene were introduced into the flask. Then heated to 120 ℃ and reacted at reflux for 48 hours. After the reaction is completed, the mixture is filtered at room temperature, the filtrate is concentrated to remove Toluene, and finally, the solvent is removed under high vacuum to obtain a product, the monomer structure of which is shown as the formula 1-3, and the structure of which is identified by using an NMR spectrum.

Example 4 Synthesis of Polymer 1

Firstly, 1.00 mole of 4,4'-Oxydianiline (ODA) is put into a reaction bottle, then NMP (N-methyl pyrrolidone) solvent is poured into the reaction bottle to ensure that the solid content of the solution is 15-20%, after the reactants are dissolved, 1.00 mole of 6-FDA (4, 4' - (Hexafluoroisopropylidene) DIPHTHALIC ANHYDRIDE) is added into the reaction bottle, and finally, the reaction bottle is stirred at room temperature for 12-18 hours to obtain the polymer solution. And coating the polymer solution on glass, placing the glass into an oven for reaction for 2-4 hours at 200-240 ℃, cooling, and then removing the film to obtain the polymer film. Wherein n is an integer greater than 1. Both Tg and CTE of Polymer 1 were measured by a static mechanical Analyzer (TMA) and the specifications were in accordance with IPC-TM-650.2.4.24.5. Td is measured by thermogravimetric analysis (TGA) and the measurement results are shown in Table 1.

Example 5 Synthesis reaction of Polymer 2

Firstly, putting 0.95 mole of ODA (4, 4 '-Oxydianiline) and 0.05 mole of AZ into a reaction bottle, then pouring NMP (N-methylpyrrolidone) solvent to ensure that the solid content of the solution is 15-20%, adding 1.00 mole of 6-FDA (4, 4' - (Hexafluoroisopropylidene) DIPHTHALIC ANHYDRIDE after the reactants are dissolved, and finally stirring for 12-18 hours at room temperature to obtain the polymer solution. And coating the polymer solution on glass, placing the glass into an oven for reaction for 2-4 hours at 200-240 ℃, cooling, and then removing the film to obtain the recyclable polymer film. Wherein n is an integer greater than 1, x and y are real numbers greater than 0 and less than 1, and x+y=1. Both Tg and CTE of Polymer 2 were measured by a static mechanical Analyzer (TMA) and the specifications were in accordance with IPC-TM-650.2.4.24.5. Td is measured by thermogravimetric analysis (TGA) and the measurement results are shown in Table 1.

EXAMPLE 6 Synthesis of Polymer 3

Firstly, putting 0.95 mole of ODA (4, 4 '-Oxydianiline) and 0.05 mole of AZ into a reaction bottle, then pouring NMP (N-methylpyrrolidone) solvent to ensure that the solid content of the solution is 15-20%, adding 0.05 mole of 6-FDA (4, 4' - (Hexafluoroisopropylidene) DIPHTHALIC ANHYDRIDE) and 0.95 mole of BPDA (Biphenyl-tetracarbonic ACID DIANHYDRIDE) after the reactants are dissolved, and finally stirring at room temperature for 12-18 hours to obtain the polymer solution. And coating the polymer solution on glass, placing the glass into an oven for reaction for 2-4 hours at 200-240 ℃, cooling, and then removing the film to obtain the recyclable polymer film. Wherein n is an integer greater than 1, x and y are real numbers greater than 0 and less than 1, and x+y=1. Both Tg and CTE of Polymer 3 were measured by a static mechanical Analyzer (TMA) and the specifications were in accordance with IPC-TM-650.2.4.24.5. Td is measured by thermogravimetric analysis (TGA) and the measurement results are shown in Table 1.

EXAMPLE 7 Synthesis of Polymer 4

Firstly, putting 0.95 mole of ODA (4, 4 '-Oxydianiline) and 0.05 mole of AFZ into a reaction bottle, then pouring NMP (N-methylpyrrolidone) solvent to ensure that the solid content of the solution is 15-20%, adding 0.05 mole of 6-FDA (4, 4' - (Hexafluoroisopropylidene) DIPHTHALIC ANHYDRIDE) and 0.95 mole of BPDA (Biphenyl-tetracarbonic ACID DIANHYDRIDE) after the reactants are dissolved, and finally stirring at room temperature for 12-18 hours to obtain the polymer solution. And coating the polymer solution on glass, placing the glass into an oven for reaction for 2-4 hours at 200-240 ℃, cooling, and then removing the film to obtain the recyclable polymer film. Wherein n is an integer greater than 1, x and y are real numbers greater than 0 and less than 1, and x+y=1. The Tg and CTE of Polymer 4 were both measured by a static mechanical Analyzer (TMA) and the specifications were in accordance with IPC-TM-650.2.4.24.5. Td is measured by thermogravimetric analysis (TGA) and the measurement results are shown in Table 1.

Example 8 Synthesis of Polymer 5

The reaction formula is as follows, according to the required medicine molar dose of Table 1, 0.95 mole of ODA (4, 4 '-Oxydianiline) and 0.05 mole of IAF-1 are put into a reaction bottle, NMP (N-methylpyrrolidone) solvent is poured into the reaction bottle to ensure that the solid content of the solution is 15-20%, after the reactants are dissolved, 0.05 mole of 6-FDA (4, 4' - (Hexafluoroisopropylidene) DIPHTHALIC ANHYDRIDE) and 0.95 mole of BPDA (Biphenyl-tetracarbonic ACID DIANHYDRIDE) are added, and finally the mixture is stirred at room temperature for 12-18 hours to obtain the polymer solution. And coating the polymer solution on glass, placing the glass into an oven for reaction for 2-4 hours at 200-240 ℃, cooling, and then removing the film to obtain the recyclable polymer film. Wherein n is an integer greater than 1, x and y are real numbers greater than 0 and less than 1, and x+y=1. Both Tg and CTE of Polymer 5 were measured by a static mechanical Analyzer (TMA) and the specifications were in accordance with IPC-TM-650.2.4.24.5. Td is measured by thermogravimetric analysis (TGA).

Thermal property testing of the polymers prepared in Table 1

	Polymer 1	Polymer 2	Polymer 3	Polymer 4	Polymer 5
						CTE(ppm/°C)	49	51	48	21	18
Tg(°C)	300	291	307	301	311
						Td(°C)	505	497	558	571	567

Recovery examples

The films of the prepared polymers 2, 3 and 5 of examples 5, 6 and 8 are cut into equal halves, and the films separated into two pieces are stacked together and recovered at a temperature of room temperature to 150 ℃. The films after recycling were subjected to the thermal property test of glass transition temperature and thermal decomposition temperature as described above, and the test results are shown in Table 2. The maintenance rate was calculated to be T2/T1 x 100% (T1: the thermal property temperature of the original film; T2: the thermal property temperature of the recycled and reworked film).

TABLE 2 thermal Property testing of polymers of the invention before and after recovery

As can be seen from the above recovery examples, the polyimide resin of the present invention has a glass transition temperature and a thermal decomposition temperature after recovery, which are almost the same as those of the polyimide resin before recovery, and therefore, the polyimide resin of the present invention has the advantages of low thermal expansion, recovery, certain heat resistance and chemical resistance after recovery, favorable recovery and reutilization of polyimide resin, reduced amount of waste materials, and realization of the object of environmental friendliness. Therefore, the invention is a novel and advanced one which can be used by industry users, and is in accordance with the requirements of patent application of the patent law.

The sequence numbers of the steps in the above embodiments do not mean the execution sequence, and the execution sequence of the processes should be determined according to the functions and internal logic, and should not limit the implementation process of the embodiments of the present application.

The foregoing description of the preferred embodiments of the present invention is not intended to limit the scope of the invention, but rather to cover all equivalent variations and modifications in shape, construction, characteristics and spirit according to the scope of the present invention as defined in the appended claims.

Claims

1. A low thermal expansion and recyclable polyimide resin, characterized in that it contains at least one unit of the following formula:

and at least one dianhydride unit;

in,

A is selected from the group consisting of:

R is selected from the group consisting of:

R ₁ is selected from -CH ₃ , -CH ₂ CH ₃ , or -CF ₃ ;

n is an integer greater than 1;

And the dianhydride unit is selected from the group consisting of:

1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, pyromellitic dianhydride, 4,4′-oxydiphthalic anhydride, bicyclo[2.2.2]octane-2,3,5,6-tetracarboxylic dianhydride 2,3,5,6-dianhydride), dicyclohexyl-3,4,3′,4′-tetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride.

2. The low thermal expansion and recyclable polyimide resin according to claim 1, characterized in that the low thermal expansion and recyclable polyimide resin comprises a unit of the following formula

and a unit of formula 1, n is an integer greater than 1, formula 1 is about 80-95% by mole, formula 2 is about 5-20% by mole, and the unit of formula 1 is different from formula 2.

3. The low thermal expansion and recyclable polyimide resin according to claim 1, characterized in that the low thermal expansion and recyclable polyimide resin comprises a unit of the following formula

and a unit of formula 1, n is an integer greater than 1, formula 1 is about 80-95% by mole, formula 3 is about 5-20% by mole, and the unit of formula 1 is different from formula 3.

4. A method for recycling a low thermal expansion and recyclable polyimide resin as claimed in claim 1, characterized in that it comprises:

Performing a dissolving step to dissolve the low thermal expansion and recyclable polyimide resin in a polar aprotic solvent to obtain a polyimide recovery solution; and

A film forming step is performed to coat and bake the polyimide recovery solution to form a recovered polyimide film.

5. The method for recovering a low thermal expansion and recyclable polyimide resin according to claim 4, wherein the polar aprotic solvent is dimethylacetamide, a dimethylacetamide derivative, N-methylpyrrolidone, or an N-methylpyrrolidone derivative.