阅读说明：本技术 一种基于双马来酰亚胺基树脂的光敏树脂组合物及其在405nm 3D打印中的应用 (Bismaleimide resin-based photosensitive resin composition and application thereof in 405nm 3D printing ) 是由 卓东贤 陈少云 华文强 瞿波 王睿 郑燕玉 刘小英 李文杰 于 2020-12-24 设计创作，主要内容包括：本发明公开了一种基于双马来酰亚胺基树脂的光敏树脂组合物及其在405nm 3D打印中的应用,所述组合物包括：10～60%含甲基丙烯酸结构的双马来酰亚胺基树脂、10～60%丙烯酸类树脂、0～25%聚乙二醇二甲基丙烯酸酯类树脂、0～25%烷氧化丙烯酸酯、0～25%稀释剂、0.1～10%光引发剂、0～5%消泡剂、0～5%流平剂和0～5%抗氧化剂。该光敏树脂组合物成本低廉、适用性广,可用于405nm光固化3D打印技术,可显著提高打印速率及打印制品的耐热与机械性能,能广泛应用于航空航天等领域。(The invention discloses a photosensitive resin composition based on bismaleimide resin and application thereof in 405nm 3D printing, wherein the composition comprises the following components: 10-60% of bismaleimide resin containing a methacrylic acid structure, 10-60% of acrylic resin, 0-25% of polyethylene glycol dimethacrylate resin, 0-25% of alkoxylated acrylate, 0-25% of a diluent, 0.1-10% of a photoinitiator, 0-5% of an antifoaming agent, 0-5% of a leveling agent and 0-5% of an antioxidant. The photosensitive resin composition has low cost and wide applicability, can be used for a 405nm photocuring 3D printing technology, can obviously improve the printing speed and the heat resistance and mechanical properties of a printed product, and can be widely applied to the fields of aerospace and the like.)

1. A photosensitive resin composition based on a bismaleimide-based resin, characterized in that: the raw materials comprise the following components in percentage by mass:

2. the bismaleimide-based resin-based photosensitive resin composition of claim 1, wherein: the bismaleimide resin containing a methacrylic acid structure is prepared in air or inert atmosphere, and the method comprises the following steps:

(1) mixing 100 parts of bismaleimide and 200 parts of aromatic diamine in terms of mole, adding 80-300 parts of organic solvent and 0.01-2 parts of catalyst, and reacting at 40-80 ℃ for 0.1-24 hours to obtain a solution A;

(2) removing the organic solvent by a method of decompression concentration to obtain a viscous liquid B;

(3) adding 0.01-1 part of catalyst and 0-0.5 part of polymerization inhibitor into the viscous liquid B by weight, slowly dropwise adding 100-400 parts of glycidyl methacrylate, and reacting at 40-90 ℃ for 0.5-36 hours to obtain the maleimide resin containing methacrylic acid, wherein the structural formula of the maleimide resin is as follows:

P：or H

R₁：

R₂：

Wherein the bismaleimide is N, N '-1, 3-phenylene bismaleimide, 4' -diphenylmethane bismaleimide or a combination of the two; the aromatic diamine is 4,4 '-diaminodiphenylmethane, p-phenylenediamine, 2' -dimethyl-4, 4 '-diaminobiphenyl, 4' -diaminodiphenyl ether or a combination thereof, the organic solvent is acetone, dichloroethane, tetrahydrofuran, trichloromethane, ethyl acetate or acetonitrile, the catalyst in the step (1) is glacial acetic acid or zinc chloride,

the catalyst in the step (3) is tetrabutylammonium bromide, tetrabutylammonium chloride, tetraethylammonium bromide, tetrabutylammonium hydrogen sulfate, benzyltriethylammonium chloride, trioctylmethylammonium chloride, dodecyltrimethylammonium chloride or tetradecyltrimethylammonium chloride; the polymerization inhibitor is hydroquinone.

3. The bismaleimide-based resin-based photosensitive resin composition of claim 1, wherein: the polyurethane acrylate resin is selected from at least one of aliphatic polyurethane acrylate oligomer, aromatic polyurethane acrylate oligomer, polyurethane diacrylate and dimethyl acrylic urethane resin;

the polymerization degree of the polyethylene glycol dimethacrylate resin is 1-200;

the alkoxylated acrylate monomer is at least one selected from glycerol oxide triacrylate and ethoxylated pentaerythritol tetraacrylate.

4. The bismaleimide-based resin-based photosensitive resin composition of claim 1, wherein: the diluent is at least one selected from styrene, acrylate diluent, acrylic hydroxy ester diluent, vinyl ether diluent and cyclohexane diluent; the acrylate diluent is at least one selected from methyl methacrylate, 1, 6-hexanediol diacrylate, isobornyl acrylate, tetrahydrofuran acrylate, tripropylene glycol diacrylate, hexanediol diacrylate, bisphenol A diacrylate, trimethylolpropane triacrylate, pentaerythritol acrylate, isobornyl acrylate and cyclic trimethylolpropane formal acrylate; the acrylate diluent is at least one selected from hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxyethyl acrylate; the vinyl ether diluent is selected from at least one of 4-hydroxybutyl vinyl ether and diethylene glycol divinyl ether; the cyclohexane diluent is selected from at least one of 4-vinyl cyclohexene oxide and 4-vinyl cyclohexene oxide.

5. The bismaleimide-based resin-based photosensitive resin composition of claim 1, wherein: the photoinitiator is selected from at least one of acylphosphine oxide photoinitiators and aromatic ketone photoinitiators, and the acylphosphine oxide photoinitiators are selected from at least one of phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide and 2, 4, 6- (trimethylbenzoyl) diphenylphosphine oxide; the aromatic ketone photoinitiator is selected from at least one of 1-hydroxy-cyclohexyl-acetophenone, alpha-dimethyl-alpha-hydroxyacetophenone, p-isopropylphenyl-2-hydroxydimethyl acetone-1, benzophenone, chlorinated benzophenone, acrylated benzophenone, 4-phenylbenzophenone, 2-chlorinated thioxanthone, isopropyl thioxanthone, 2-hydroxy-2-methyl-1-phenyl-1-acetone, dimethyl thioxanthone, diethyl thioxanthone, dichloro thioxanthone and 2-phenylbenzyl-2-dimethylamine-1- (4-morpholine benzyl) butanone.

6. The bismaleimide-based resin-based photosensitive resin composition of claim 1, wherein: the defoaming agent is at least one of silicone defoaming agent, mineral oil defoaming agent, polyether defoaming agent and fatty alcohol defoaming agent.

7. The bismaleimide-based resin-based photosensitive resin composition of claim 1, wherein: the flatting agent is selected from at least one of acrylic flatting agents, organic silicon flatting agents and fluorocarbon flatting agents; the antioxidant is selected from at least one of pentaerythritol tetrakis (3, 5-di-tert-butyl-4-hydroxy) phenylpropionate, tris (2, 4-di-tert-butyl) phenyl phosphite, N' -bis- (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl) hexanediamine and 2, 6-di-tert-butyl-4-methylphenol.

8. The method for preparing a bismaleimide resin-based photosensitive resin composition as claimed in any one of claims 1 to 7, wherein: mixing bismaleimide resin, acrylate resin, polyethylene glycol dimethacrylate resin, alkoxylated acrylate and a diluent, heating to 30-80 ℃, stirring and mixing uniformly, cooling, adding a photoinitiator, a defoaming agent, a leveling agent and an antioxidant, and stirring uniformly to obtain the photosensitive resin composition.

9. Use of the bismaleimide resin-based photosensitive resin composition as claimed in any one of claims 1 to 7, wherein: the photosensitive resin composition based on bismaleimide resin is used in 405nm photocuring 3D printing, and the obtained preform is subjected to ultraviolet irradiation and thermosetting treatment to obtain a molded part.

10. The use of the bismaleimide resin-based photosensitive resin composition as claimed in claim 9, wherein: the thermosetting treatment comprises four stages, wherein the temperature of the first stage is 150-170 ℃, and the time is 1-3 hours; the temperature of the second stage is 180-200 ℃, and the time is 1-3 hours; the temperature of the third stage is 210-220 ℃, and the time is 2-4 hours; the temperature of the fourth stage is 230-240 ℃ and the time is 2-4 hours.

Technical Field

The invention relates to the field of photosensitive resin processing and application thereof, in particular to a bismaleimide resin-based photosensitive resin composition and application thereof in 405nm 3D printing.

Background

3D printing can be directly computer controlled, without a mold, built up layer by layer into an object, with many advantages over traditional manufacturing methods. Compared with other forming technologies, the photocuring forming technology has the advantages of high speed, short curing forming time, energy conservation and no pollution, and the formed material has excellent performances in the aspects of hardness, chemical resistance, wear resistance and the like. Currently, Digital Light Processing (DLP), laser Stereo curing (SLA), and Liquid Crystal projection curing (LCD) are the main common photocuring 3D printing technologies. Many of these mainstream photo-curing techniques utilize 405nm ultraviolet light as a light source.

With the rapid development of 3D printing technology, the requirements of people on the quality of photocuring three-dimensional printed products are higher and higher, and the photosensitive resin is used as a forming consumable material of the photocuring technology, so that the application prospect of the technology is directly influenced. Commonly used photosensitive resins are epoxy resins and acrylate resins. These resins can produce complex structures, but have significant drawbacks in terms of heat resistance, mechanical properties, etc. Particularly, in some specific fields such as the field of aviation, the field of medical instruments, etc., these high-molecular-weight photosensitive resins have not been satisfactory. Therefore, the development of novel photosensitive resin materials is gradually becoming the key of innovative breakthrough of photochemical polymerization technology and is a necessary way to expand the application field of photochemical polymerization technology.

In order to improve the heat resistance and mechanical properties of the photocuring 3D printing product, various modes such as developing novel resin, adjusting a formula, adding inorganic filler and the like are generally adopted in the industry to improve the comprehensive properties of the photosensitive resin. Polyimide ink 3D printed with a product having a tensile strength of 24.9MPa and a decomposition temperature of 432 ℃ as synthesized in the document "Solvent-free and photocurable polyimide inks for 3D printing" (Y.Guo, Z.Ji, Y.Zhang, X.Wang and F.Zhou, J MATER CHEM A,2017,5, 16307-. The elastic modulus of the polymer resin ranges between 0.6MPa and 31MPa by varying the proportions of monomer and crosslinker starting materials in the formulation as reported in the document "3D printing a mechanical-structural acrylate resin on a commercial DLP-SLA printer" (J.Borrello, P.Nasser, J.C.Iatridis and K.D.Costa, Additive Manufacturing,2018,23, 374-380). The documents underwent and influencing Mechanical Properties in 3D printed Parts Using a Dual-Cure Acrylate-Based Resin for Stereolithography (A.M.V.L. Asais Camila Ulzcategui, ADV ENG MATER,2018,20,1800876.) the hardness and tensile strength (79.3HD and 30.4MPa) of the samples were obtained by calcium sulfate whisker modification. The prior art has the technical effect that the mechanical property and the heat resistance are difficult to be simultaneously improved. The development of novel photopolymers to broaden the application field of 3D printed objects remains a hot topic of the materials field.

Bismaleimide-based resin materials have good mechanical properties and excellent heat resistance, but have poor moldability. Therefore, based on the thought, the photosensitive resin composition for 405nm photocuring 3D printing based on the bismaleimide resin is developed, so that the application of the bismaleimide resin is widened, and the defect of poor formability is overcome; and a novel high-performance photosensitive resin composition is obtained, which is beneficial to popularization and promotion of a 405nm photocuring 3D printing technology. In "a polyimide photosensitive material for 3D printing" (wang dao long chinese patent, 105837760,2016-08-10), it is reported that 4,4' -bismaleimide diphenylmethane reacts with 3,3 ' -dihydroxy-4, 4' -diaminodicyclohexylmethane, maleic anhydride, and then reacts with glycidyl acrylate to attach a photosensitive group. The technology comprises the following steps: 1) the synthesis steps are relatively complicated and difficult to industrialize; 2) too many non-five-membered ring and six-membered ring structures are introduced, so that the heat resistance and mechanical property loss of the BMI is serious; 3) only 2 photosensitive groups are needed, so that the UV curing activity is difficult to control, and the photocuring speed is slow. Aiming at the defects of the existing BMI photosensitive resin preparation method, a novel bismaleimide resin with excellent performance and simple synthesis process is developed, and meanwhile, the photosensitive resin is still the focus of research when being used for photocuring 3D printing.

Disclosure of Invention

In view of the circumstances and disadvantages of the prior art, an object of the present invention is to provide a bismaleimide-based resin-based photosensitive resin composition having good mechanical properties and excellent heat resistance, and its use in 405nm 3D printing.

In order to achieve the technical purpose, the invention adopts the technical scheme that:

the bismaleimide-based photosensitive resin composition comprises the following raw materials in percentage by mass based on 100% of the total mass:

preferably, the synthesis route of the bismaleimide-based resin is shown in the attached figure 1, and the synthesis steps comprise:

(1) mixing 100 parts of bismaleimide and 200 parts of aromatic diamine in terms of mole, adding 80-300 parts of organic solvent and 0.01-2 parts of catalyst, and reacting at 40-80 ℃ for 0.1-24 hours to obtain a solution A;

(2) removing the organic solvent by a method of decompression concentration to obtain a viscous liquid B;

(3) adding 0.01-1 part by weight of catalyst and 0-0.5 part by weight of polymerization inhibitor into the viscous liquid B, slowly dropwise adding 100-400 parts by weight of glycidyl methacrylate, and reacting at 40-90 ℃ for 0.5-36 hours; obtaining the maleimide resin containing methacrylic acid, wherein the structural formula of the maleimide resin is as follows:

P：or H

In terms of mole ratio, bismaleimide: aromatic diamine (b): glycidyl methacrylate ether ═ 1:2 (1-4).

Wherein the bismaleimide is N, N '-1, 3-phenylene bismaleimide, 4' -diphenylmethane bismaleimide or a combination thereof; the aromatic diamine is 4,4 '-diaminodiphenylmethane, p-phenylenediamine, 2' -dimethyl-4, 4 '-diaminobiphenyl, 4' -diaminodiphenyl ether or their combination. The organic solvent is acetone, dichloroethane, tetrahydrofuran, chloroform, ethyl acetate, acetonitrile or a combination thereof. The catalyst in the step (1) is glacial acetic acid, zinc chloride or a combination thereof.

The catalyst in the step (3) is tetrabutylammonium bromide, tetrabutylammonium chloride, tetraethylammonium bromide, tetrabutylammonium hydrogen sulfate, benzyltriethylammonium chloride, trioctylmethylammonium chloride, dodecyltrimethylammonium chloride, tetradecyltrimethylammonium chloride or a combination thereof; the polymerization inhibitor is hydroquinone, methyl hydroquinone, p-hydroxyanisole, 2-tertiary butyl hydroquinone, 2, 5-ditertiary butyl hydroquinone or the combination thereof.

Preferably, the urethane acrylate resin is at least one selected from the group consisting of aliphatic urethane acrylate oligomer, aromatic urethane acrylate oligomer, urethane diacrylate and urethane dimethacrylate resin.

Preferably, the polymerization degree of the polyethylene glycol dimethacrylate resin is 1-200.

Preferably, the alkoxylated acrylate monomer is selected from at least one of glycerol triacrylate, ethoxylated pentaerythritol tetraacrylate.

Preferably, the diluent is at least one selected from styrene, acrylate diluents, hydroxy acrylate diluents, vinyl ether diluents and cyclohexane diluents. Further preferably, the acrylate diluent is at least one selected from the group consisting of methyl methacrylate, 1, 6-hexanediol diacrylate, isobornyl acrylate, tetrahydrofuran acrylate, tripropylene glycol diacrylate, hexanediol diacrylate, bisphenol a diacrylate, trimethylolpropane triacrylate, pentaerythritol acrylate, isobornyl acrylate, and cyclic trimethylolpropane formal acrylate; the acrylate diluent is at least one selected from hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxyethyl acrylate; the vinyl ether diluent is selected from at least one of 4-hydroxybutyl vinyl ether and diethylene glycol divinyl ether; the cyclohexane diluent is selected from at least one of 4-vinyl cyclohexene oxide and 4-vinyl cyclohexene oxide.

Preferably, the photoinitiator is selected from at least one of acylphosphine oxide photoinitiators and aromatic ketone photoinitiators. Further preferably, the acylphosphine oxide photoinitiator is selected from at least one of phenyl bis (2, 4, 6-trimethylbenzoyl) phosphine oxide and 2, 4, 6- (trimethylbenzoyl) diphenylphosphine oxide; the aromatic ketone photoinitiator is selected from at least one of 1-hydroxy-cyclohexyl-acetophenone, alpha-dimethyl-alpha-hydroxyacetophenone, p-isopropylphenyl-2-hydroxydimethyl acetone-1, benzophenone, chlorinated benzophenone, acrylated benzophenone, 4-phenylbenzophenone, 2-chlorinated thioxanthone, isopropyl thioxanthone, 2-hydroxy-2-methyl-1-phenyl-1-acetone, dimethyl thioxanthone, diethyl thioxanthone, dichloro thioxanthone and 2-phenylbenzyl-2-dimethylamine-1- (4-morpholine benzyl) butanone.

Preferably, the defoaming agent is selected from at least one of silicone defoaming agents, mineral oil defoaming agents, polyether defoaming agents and fatty alcohol defoaming agents.

Preferably, the leveling agent is selected from at least one of an acrylic leveling agent, an organic silicon leveling agent, and a fluorocarbon leveling agent.

Preferably, the antioxidant is at least one selected from pentaerythritol tetrakis (3, 5-di-tert-butyl-4-hydroxy) phenylpropionate, tris (2, 4-di-tert-butyl) phenyl phosphite, N' -bis- (3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl) hexanediamine and 2, 6-di-tert-butyl-4-methylphenol.

Further, the preparation method of the photosensitive resin composition based on bismaleimide resin comprises the following steps: mixing bismaleimide resin, acrylate resin, polyethylene glycol dimethacrylate resin, alkoxylated acrylate and a diluent, heating to 30-80 ℃, stirring and mixing uniformly, cooling, adding a photoinitiator, a defoaming agent, a leveling agent and an antioxidant, and stirring uniformly to obtain the photosensitive resin composition.

According to the application of the bismaleimide-based photosensitive resin composition, the bismaleimide-based photosensitive resin composition is used for 405nm photocuring 3D printing, and the obtained preform is subjected to ultraviolet irradiation and thermocuring treatment to obtain a molded part.

Preferably, the thermal curing process comprises four stages: the temperature of the first stage is 150-170 ℃, and the time is 1-3 hours; the temperature of the second stage is 180-200 ℃, and the time is 1-3 hours; the temperature of the third stage is 210-220 ℃, and the time is 2-4 hours; the temperature of the fourth stage is 230-240 ℃ and the time is 2-4 hours.

By adopting the technical scheme, compared with the prior art, the invention has the beneficial effects that: the bismaleimide resin containing a methacrylic acid structure is introduced into the photosensitive resin composition, so that the characteristics of the bismaleimide resin can be kept, and a printed product has excellent heat resistance and good mechanical properties, so that the bismaleimide resin can be widely applied to the fields of aerospace and the like. Meanwhile, the photosensitive resin composition of the bismaleimide-based resin for 3D printing provided by the invention has the advantages of good printability, capability of printing a complex structure, low preparation cost, effective reduction of the problems of high price and the like of the 3D printing resin, and lays a foundation for large-scale application of a 3D printing technology.

Drawings

FIG. 1 shows a synthetic route of a bismaleimide-based resin containing a methacrylic structure according to the present invention.

FIG. 2 is a printed model of the bismaleimide photosensitive resin composition prepared in example 1 of the present invention on a 405nm 3D printer.

FIG. 3 is a stress-strain curve of a bar tensile test printed on a 405nm 3D printer for a bismaleimide photosensitive resin composition prepared in example 1 of the present invention.

FIG. 4 is a stress-strain curve of a sample bending test printed on a 405nm 3D printer with the bismaleimide photosensitive resin composition prepared in example 1 of the present invention.

FIG. 5 is a thermal weight loss (TGA) curve of a product printed by a 405nm 3D printer of the bismaleimide photosensitive resin composition prepared in example 1 of the present invention.

FIG. 6 is a dynamic thermal mechanical (DMA) curve of a printed article of the bismaleimide photosensitive resin composition prepared in example 1 of the present invention at a 405nm 3D printer.

Detailed Description

The invention is further illustrated with reference to the following specific embodiments:

bismaleimide-based resin containing a methacrylic structure:

n, N' -1, 3-phenylenebismaleimide resin, abbreviated as A-1;

4,4' -diphenylmethane bismaleimide resin, abbreviated as A-2;

urethane acrylate resin:

aliphatic urethane acrylate 1: purchased from sandoma corporation, product number CN9010, abbreviated as B-1;

aliphatic urethane acrylate 2: purchased from sandoma corporation under product number CN991, abbreviated as B-2;

polyethylene glycol dimethacrylate resin:

polyethylene glycol dimethacrylate resin 1: purchased from sandoma corporation, product number SR210, abbreviated as C-1;

polyethylene glycol dimethacrylate resin 2: purchased from sandoma corporation, product number SR211, abbreviated as C-2;

alkoxylated acrylates:

ethoxylated pentaerythritol tetraacrylate, available from sandomar under the product number SR494, abbreviated as D-1;

glycerol propylene oxide triacrylate, available from sartomer company under product number SR9020, abbreviated as D-2;

diluent agent:

cyclotrimethylolpropane formal acrylate: purchased from sandoma corporation under product number SR351, abbreviated as E-1;

hydroxypropyl methacrylate: available from Aladdin reagent (Shanghai) Inc., abbreviated as E-2;

hydroxyethyl methacrylate: purchased from Aladdin reagent (Shanghai) Co., Ltd, abbreviated as E-3;

photoinitiator (2):

2, 4, 6- (trimethylbenzoyl) diphenylphosphine oxide, available from the group of the Aladdin reagents (Shanghai) Ltd, product number photoinitiator TPO, abbreviated to F-1;

phenylbis (2, 4, 6-trimethylbenzoyl) phosphine oxide: purchased from Aladdin reagent (Shanghai) Inc., product number photoinitiator XBPO, abbreviated as F-2;

1-hydroxy-cyclohexyl-acetophenone: available from Allantin reagents (Shanghai) Inc., product number photoinitiator 184, abbreviated as F-3;

defoaming agent:

silicone defoaming agent: purchased from Bike chemical company, Germany, under the product number BYK-088, abbreviated as G-1;

polyether defoaming agent: purchased from Guangdong Union of China, Fine chemical Co., Ltd, product number B-299, abbreviated as G-2;

leveling agent:

an organic silicon leveling agent: purchased from Anhui Jia Xinnuo chemical products, Inc., product number WE-D5510, abbreviated as H-1;

polyacrylic acid leveling agent: purchased from Anhui Jia Xinnuo chemical products, Inc., product number WE-D819, abbreviated as H-2;

antioxidant:

2, 6-di-tert-butyl-4-methylphenol: available from Allantin reagent (Shanghai) Co., Ltd, product number antioxidant BHT, abbreviated as I-1;

pentaerythritol tetrakis (3, 5-di-tert-butyl-4-hydroxy) phenylpropionate: purchased from Kyon chemical Co., Ltd, Guangzhou, antioxidant 1010, abbreviated as I-2.

The reference raw material composition formula of the photosensitive resin composition based on bismaleimide resin in this embodiment is as follows:

the formula is composed of the following components in proportion to obtain the following 1# -8 # implementation formula:

the preparation steps are as follows: mixing a proper amount of bismaleimide resin, acrylate resin, polyethylene glycol dimethacrylate resin, alkoxylated acrylate and a diluent, heating to 30-80 ℃, uniformly stirring and mixing, cooling, adding a photoinitiator, a defoaming agent, a leveling agent and an antioxidant, and uniformly stirring to obtain a yellow viscous liquid, thereby obtaining the photosensitive resin composition sample.

The formulated photosensitive resin composition was poured into a Form 23D printer manufactured by fomlebus (Formlabs) corporation, usa, and molded by computer modeling, patterning, and printing. Carrying out ultraviolet curing and thermocuring treatment on the obtained product; wherein the light intensity of the ultraviolet light is 100W/cm²The ultraviolet curing time is 10min, and the thermal curing process is 160 ℃/2h +180 ℃/2h +220 ℃/2h +240 ℃/4 h.

For the products obtained in the above examples, the photosensitive resin composition was evaluated by observing the appearance of the cured product, and the results were as follows:

referring to FIG. 2, it is a sample printed by a 405nm 3D printer of the bismaleimide photosensitive resin composition prepared in example 1 of the present invention.

Referring to FIGS. 3 and 4, there are respectively shown stress-strain curves of a bar tensile test and a bending test printed on a 405nm 3D printer of the bismaleimide photosensitive resin composition prepared in example 1 of the present invention. It can be seen that the bismaleimide photosensitive resin composition prepared in example 1 had a tensile strength of 64.5MPa, an elongation at break of 9.0%, and a flexural strength of 84.7MPa, and thus it was excellent in mechanical properties.

Referring to FIG. 5, there is shown a thermogravimetric analysis (TGA) curve of the bismaleimide photosensitive resin composition prepared in example 1 of the present invention under a nitrogen atmosphere at a temperature rising rate of 10 deg.C/min. The initial thermal decomposition temperature is 327.1 ℃, the maximum decomposition temperature is 407.9 ℃, and the carbon residue rate at 800 ℃ is 14.1%. Referring to FIG. 5, which is a dynamic thermal mechanical (DMA) curve of a sample printed by a 405nm 3D printer from the bismaleimide resin composition prepared in example 1 of the present invention, it can be seen that the glass transition temperature can reach 133.4 ℃ and the storage modulus at 35 ℃ can reach 2931.1 MPa. Indicating that the printed article based on the bismaleimide photosensitive resin composition has good heat resistance.

Although the present application has been described with reference to a few embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the application as defined by the appended claims.