CN113059808B - Method for selectively processing 3D printing model by functionalized digital light - Google Patents

Abstract

The invention provides a method for selectively functionalizing a digital light processing 3D printing model, which comprises the following steps: preparing a neutral photosensitive resin containing a photocurable monomer (a); preparing a positively charged group-carrying photosensitive resin containing a cationic monomer, a diluent and a photocurable monomer (B); introducing a model to be printed into a digital light processing 3D printer, and respectively printing and curing by using neutral photosensitive resin and photosensitive resin with positive charge groups according to the design of the model to obtain the model; cleaning the obtained model, and removing uncured monomers; dispersing a functional material in a solution containing an anionic surfactant to obtain a negatively charged functional material dispersion liquid; the mold was immersed in the functional material dispersion liquid and taken out after a predetermined period of time. The method has the characteristics of simplicity, convenience, high efficiency and low cost, and has wide application prospect in the preparation of 3D printing electronic devices.

Description

Method for selectively functionalizing digital light processed 3D printed models

technical field

The invention belongs to the technical field of additive manufacturing, and in particular relates to a method for selectively functionalizing digital light processing 3D printing models based on electrostatic adsorption.

Background technique

Additive manufacturing (also known as 3D printing) refers to a set of techniques for fabricating three-dimensional objects directly from a computer-aided design (CAD) model in a layer-by-layer fashion, allowing almost any arbitrarily complex object to be produced in a simple and low-cost manner . Many 3D printing technologies have been developed today, such as Fused Deposition (FDM), Selective Laser Melting (SLM), Stereolithography (SLA), Digital Light Processing (DLP), which are used in metal parts, aerospace, biomedical engineering It has important applications in the fields of , sensors and microelectronics. The basic principle of digital light processing 3D printing technology is that the digital light source performs layer-by-layer projection on the surface of the liquid photosensitive resin in the form of surface light, and the layers are cured and formed. DLP-3D printing has its unique advantages over other types of 3D printing technologies: no moving beam, small vibration deviation, no moving nozzles, no material blocking problems at all, no heating parts, improved electrical safety, short print preparation time, saving Energy, the amount of consumables added for the first time is far less than other equipment, saving user costs.

For the 3D printing of electronic devices, the functionalization step is essential. For the functionalization of digital light processing 3D printing models, there are mainly two routes: one is to mix functional materials into resin raw materials to directly print the model, but it will It has the disadvantages of uneven dispersion and poor printing quality; the second is to use raw materials to print out the model and then prepare the active layer, which is complicated in operation, high in cost and cannot be selectively functionalized.

Therefore, a simple, efficient and low-cost method for selectively functionalizing digital light processing 3D printed models is needed.

SUMMARY OF THE INVENTION

The present invention is accomplished in order to solve the problems existing in the prior art, and its purpose is to provide a simple, efficient and low-cost method for selectively functionalizing 3D printing models based on electrostatic adsorption by digital light processing.

In order to achieve the above purpose, the inventor first prepared neutral photosensitive resin and photosensitive resin with positively charged groups and put them into the material box of the digital light processing 3D printer, and then imported the model drawn by the three-dimensional drawing software into the digital light processing 3D printer. , using two photosensitive resins to print the model by digital light processing 3D printer, then dispersing the functional material with an anionic dispersant to obtain a negatively charged functional material dispersion, and finally immersing the obtained model in the dispersion, so that the functional material is electrostatically adsorbed (Adsorption of positive and negative charges) is bonded to the part of the model that is cured and molded by the photosensitive resin with positively charged groups, so that the digital light processing 3D printing model can be functionalized easily and efficiently, thereby completing the present invention.

The method for selectively functionalizing digital light processing 3D printing models of the present invention comprises the following steps:

Prepare a neutral photosensitive resin containing a photocurable monomer (A);

preparing a photosensitive resin with positively charged groups comprising a cationic monomer, a diluent and a photocurable monomer (B);

The model to be printed is imported into a digital light processing 3D printer, and the above-mentioned neutral photosensitive resin and the above-mentioned photosensitive resin with positively charged groups are used to print and cure respectively according to the design of the model to obtain the model;

The above-mentioned model obtained is cleaned to remove uncured monomers;

Disperse the functional material in a solution containing an anionic surfactant to obtain a negatively charged functional material dispersion;

The above-mentioned model is immersed in the above-mentioned functional material dispersion liquid, and is taken out after a predetermined period of time.

In some preferred embodiments, the above-mentioned photocurable monomer (A) is selected from polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate At least one of ester, 1,6-hexanediol diacrylate, and trimethylolpropane triacrylate. For flexible devices, the photocurable monomer (A) more preferably uses aliphatic monofunctional acrylates such as EBECRYL 113, EBECRYL 114.

In some preferred embodiments, the above-mentioned cationic monomer is selected from the group consisting of methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, methacryloylpropyltrimethylammonium chloride At least one of ammonium chloride, acryloylpropyltrimethylammonium chloride, methacryloyloxyethylbenzyldimethylammonium chloride, and acryloyloxyethylbenzyldimethylammonium chloride .

In some preferred embodiments, the above-mentioned diluent is selected from diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, and at least one of tri(ethylene glycol) divinyl ether.

In some preferred embodiments, the above-mentioned photocurable monomer (B) is selected from the group consisting of bisphenol A glycerol dimethacrylate, bisphenol A glycerol diacrylate, ethoxylated bisphenol A diacrylate Any of acrylates, propoxylated bisphenol A diacrylate, propoxylated ethoxylated bisphenol A diacrylate, ethoxylated bisphenol A dimethacrylate.

In some preferred embodiments, the above-mentioned neutral photosensitive resin and the above-mentioned photosensitive resin with positively charged groups further comprise a photoinitiator, and the above-mentioned photoinitiator is selected from phenylbis(2,4,6-trimethyl) Benzoyl) phosphine oxide, (2,4,6-trimethylbenzoyl) diphenyl phosphine oxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl -At least one of 1-acetone and benzoin anisole.

In some preferred embodiments, the above-mentioned anionic surfactant is at least one of sodium dodecyl sulfate, sodium dodecyl sulfonate, and sodium hexadecyl sulfonate.

In some preferred embodiments, the above-mentioned functional material is any one of carbon nanotubes, graphene, nanosilver wires, and copper nanowires.

In some preferred embodiments, when printing using a digital light processing 3D printer, the exposure parameters are set to 7-10.

In some preferred embodiments, when the above-mentioned model is immersed in the above-mentioned functional material dispersion liquid, the immersion time is 10-30 minutes.

In some preferred embodiments, the above-mentioned model is cleaned with a cleaning agent, and the cleaning agent is preferably at least one selected from ethanol, propanol or acetone.

In some preferred embodiments, deionized water is used for cleaning after removing the model from the functional material dispersion.

Invention effect

According to the present invention, the prepared neutral photosensitive resin and the photosensitive resin with positively charged groups are cured and molded using a digital light processing 3D printer to obtain a partially positively charged model, and then the obtained model is immersed in the negatively charged functional material to disperse In the liquid, the functional material is combined into the part of the model cured by the photosensitive resin with positively charged groups through electrostatic adsorption, so as to form a conductive layer in a specific area of the model, thereby providing a convenient, efficient and low-cost electrostatic adsorption-based A method for selectively functionalizing digital light processed 3D printed models.

Other beneficial effects of the present invention will be further illustrated in the following detailed description of the present invention.

Description of drawings

Fig. 1 is a flow chart of the selectively functionalized DLP-3D printing model of the present invention, wherein Fig. 1(a) shows an interdigital electrode printed by a digital light processing 3D printer. Photosensitive resin printing of agglomerates, the substrate part is printed with neutral photosensitive resin, Fig. 1(b) shows the selective functionalization of the interdigital electrodes immersed in the negatively charged functional material dispersion, Fig. 1(c) shows the selective functionalization In the functionalized model, a functional material layer is formed on the interdigital portion.

Figure 2 is the zeta potential of the positively charged surface model and negatively charged functional material (CNT) dispersion liquid printed by DLP-3D of the present invention at different pH.

FIG. 3 is an SEM image ( FIG. 3 a ) and an EDS image of S element ( FIG. 3 b ) of the surface of the DLP-3D printing model prepared in Example 1 of the present invention after being selectively functionalized with carbon nanotubes.

FIG. 4 is a SEM image of the surface of the DLP-3D printing model prepared in Example 2 of the present invention after being selectively functionalized with silver nanowires.

Detailed ways

The technical features of the present invention are described below with reference to the preferred embodiments and the accompanying drawings, which are intended to illustrate the present invention rather than limit it. The drawings are greatly simplified for illustrative purposes and are not necessarily drawn to scale.

It should be understood that the accompanying drawings are merely preferred embodiments of the present invention, which are not intended to limit the scope of the present invention. Those skilled in the art can make various obvious modifications, variations and equivalent replacements to the present invention on the basis of the embodiments shown in the accompanying drawings, and under the premise of no contradiction, in the different embodiments described below The technical features can be combined arbitrarily, and these all fall within the protection scope of the present invention.

The method for selectively functionalizing digital light processing 3D printing models of the present invention comprises the following steps:

(1) preparing a neutral photosensitive resin containing the photocurable monomer (A);

(2) preparing a photosensitive resin containing a cationic monomer, a diluent and a positively charged group of the photocurable monomer (B);

(3) import the model to be printed into a digital light processing 3D printer, and use the neutral photosensitive resin and the photosensitive resin with positively charged groups to print according to the design of the model to obtain a model;

(3) cleaning the obtained model to remove uncured monomer;

(4) dispersing the functional material in a solution containing an anionic surfactant to obtain a negatively charged functional material dispersion;

(5) The mold is immersed in the functional material dispersion liquid, and taken out after a predetermined period of time.

Neutral photosensitive resin

The neutral photosensitive resin according to the present invention contains a photocurable monomer (A) and a photoinitiator. This neutral photosensitive resin is used to form a substrate of a model and other parts that do not need to be functionalized.

As the above-mentioned photocurable monomer (A), a (meth)acrylate monomer having a hydroxyl group or an ether bond in the molecule can be used, for example, polyethylene glycol diacrylate, polyethylene glycol dimethyl Acrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, 1,6-hexanediol diacrylate, and trimethylolpropane triacrylate, these monomers may be used alone or in combination Two or more monomers are used in combination, and among them, polyethylene glycol diacrylate and polyethylene glycol dimethacrylate are preferably used. For flexible devices, aliphatic monofunctional acrylates, such as EBECRYL113 and EBECRYL 114, can be used. . The content ratio of the photocurable monomer (A) in the neutral photosensitive resin is preferably 80% by weight or more, more preferably 85 to 95% by weight.

The neutral photosensitive resin may contain other polymerizable monomers, such as olefins, epoxy resins, and the like, without affecting the charging characteristics of the neutral photosensitive resin. The content ratio of other polymerizable monomers in the neutral photosensitive resin is preferably 10% by weight or less, more preferably 5% by weight or less.

As the above-mentioned photoinitiator, an ultraviolet photoinitiator is preferably used, and examples thereof include phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, (2,4,6-trimethylbenzoyl) ) diphenylphosphine oxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, benzoin anisole. These photoinitiators may be used alone or in combination of two or more, but phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide or (2,4) is particularly preferred. , 6-trimethylbenzoyl) diphenylphosphine oxide. In the neutral photosensitive resin, the content of the photoinitiator is preferably 5% by weight or less, preferably 1 to 5% by weight, and more preferably 1 to 3% by weight.

In some preferred embodiments, when preparing the above-mentioned neutral photosensitive resin, a photoinitiator is added to the photocurable monomer (A), and then shaken for 1-10 minutes by a shaker, and then left to stand for defoaming after mixing uniformly. .

Photosensitive resin with positively charged groups

The photosensitive resin with a positively charged group involved in the present invention comprises a photosensitive resin with a positively charged group of a cationic monomer, a diluent, a photocurable monomer (B) and a photoinitiator. By using the photosensitive resin with positively charged groups for 3D printing, the part of the 3D printing model that needs to be functionalized can be formed. As described below, after the photosensitive resin with positively charged groups is photocured, the cationic monomer The polymer is incorporated into the cross-linked polymer matrix through polymerization, so that its surface is positively charged, and can be combined with negatively charged functional materials through electrostatic adsorption to achieve surface functionalization.

As the cationic monomer, a polymerizable monomer capable of generating a cation and having an unsaturated bond can be used, and it is particularly preferable to use a water-soluble quaternary ammonium salt of a polymerizable monomer having an acryloyl group, and specific examples thereof include methacryloyloxyethyl Trimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, methacryloylpropyltrimethylammonium chloride, acryloylpropyltrimethylammonium chloride, methacryloyloxyethyl Benzyldimethylammonium chloride and acryloyloxyethylbenzyldimethylammonium chloride may be used alone or in combination of two or more. Among them, methacryloyloxyethyltrimethylammonium chloride or acryloyloxyethyltrimethylammonium chloride is preferably used. The cationic monomer is preferably blended into the photosensitive resin in the form of an aqueous solution, and the concentration of the aqueous solution may be 60 to 85% by weight, preferably 80% by weight.

The above-mentioned diluent is added in order to reduce the viscosity of the photosensitive resin, and can be a glycol acrylate, specifically diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethyl acrylate. Monoacrylate, triethylene glycol diacrylate, tris(ethylene glycol) divinyl ether, etc., these may be used individually by 1 type, and may be used in combination of 2 or more types of monomers. Among them, triethylene glycol dimethacrylate or triethylene glycol diacrylate is particularly preferably used. In the photosensitive resin having a positively charged group, the content ratio of the diluent is preferably 10 to 35% by weight, more preferably 20 to 30% by weight.

The above-mentioned photocurable monomer (B) is a monomer for producing a photocured product having toughness and heat resistance, preferably a (meth)acrylate having a bisphenol A skeleton, and specific examples thereof include bisphenol A glycerol Alcohol Dimethacrylate, Bisphenol A Glycerol Diacrylate, Ethoxylated Bisphenol A Diacrylate, Propoxylated Bisphenol A Diacrylate, Propoxylated Ethoxylated Bisphenol A Diacrylate, ethoxylated bisphenol A dimethacrylate. These may be used individually by 1 type, and may be used in combination of 2 or more types of monomers. Among them, bisphenol A glycerol dimethacrylate or bisphenol A glycerol diacrylate is particularly preferable. In the photosensitive resin having a positively charged group, the content ratio of the photocurable monomer (B) is preferably 20 to 40% by weight, more preferably 30 to 40% by weight.

As the photoinitiator in the photosensitive resin with a positively charged group, an ultraviolet photoinitiator is preferably used, for example, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, (2,4 , 6-trimethylbenzoyl) diphenylphosphine oxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, benzoin anisole. These photoinitiators may be used alone or in combination of two or more, but phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide or (2,4) is particularly preferred. , 6-trimethylbenzoyl) diphenylphosphine oxide. In the photosensitive resin with a positively charged group, the content ratio of the photoinitiator is preferably 5% by weight or less, preferably 1 to 5% by weight, and more preferably 1 to 3% by weight.

In some preferred embodiments, when preparing the photosensitive resin with positively charged groups, the aqueous solution of the photocurable monomer (B), diluent, and cationic monomer is put into a beaker in a prescribed proportion, and a glass rod is used. Stir and mix evenly, then add a prescribed amount of photoinitiator, use a magnetic stirrer to stir at a speed of 500-800 rpm for 1 to 2 hours, fully mix and let stand for defoaming.

Digital Light Processing 3D Printing

The present invention uses a digital light processing 3D printer to perform 3D printing and curing of the model. Use 3D digital modeling software to design the model to be printed, import it into a digital light processing 3D printer, and use the above-prepared neutral photosensitive resin and photosensitive resin with positively charged groups for printing and curing according to the design of the model. A model including a portion formed from a neutral photosensitive resin that does not require functionalization (eg, a substrate) and a portion formed from a photosensitive resin with positively charged groups that does not require functionalization.

In some preferred embodiments, as the above-mentioned digital light processing 3D printer, a B9Core530DLP-3D printer (B9Creations Company) can be used, the wavelength of ultraviolet light used is 405 nm, and the exposure parameters are set to 7-10. By using this equipment and conditions, the 3D printing of the model can be carried out simply and quickly.

In some preferred embodiments, after the model is taken out, it is rinsed with a solvent such as absolute ethanol or isopropanol to dissolve and remove uncured monomers in the model, and finally blow out with nitrogen.

Negatively charged functional material dispersions

The negatively charged functional material dispersion liquid according to the present invention is obtained by dispersing the functional material in a solution containing an anionic surfactant.

The above-mentioned anionic surfactant is not particularly limited, as long as it can adhere to the surface of the functional material and make the functional material negatively charged, for example, sodium dodecyl sulfate, sodium dodecyl sulfonate, ten Sodium hexaalkylsulfonate, etc., these anionic surfactants may be used individually by 1 type, and may be used in combination of 2 or more types. Among them, sodium lauryl sulfate is particularly preferably used.

As the above-mentioned functional material, a nanomaterial having excellent electrical conductivity is preferable, and for example, it may be any one selected from the group consisting of carbon nanotube, graphene, nanosilver wire, and nanocopper wire. As the solvent for dispersing the functional material, deionized water, ethanol, or isopropanol can be used. Among them, deionized water is particularly preferably used as a dispersion solvent for carbon nanotubes, and as a dispersion solvent for silver nanowires, it is particularly preferably used isopropyl alcohol.

In some preferred embodiments, the functional material and the anionic surfactant are added to the dispersing solvent under the condition that the concentration of the functional material is 0.1-2.0 mass % and the concentration of the anionic surfactant is 0.2-1.0 mass %, and ultrasonic dispersion is carried out. After 1 to 2 hours, let it stand, and take the supernatant for use.

In some preferred embodiments, the 3D printing model obtained above is immersed in the functional material dispersion (supernatant) for 10-30 minutes, and then the model is taken out, rinsed with deionized water, and blown with nitrogen.

By immersing the 3D printed model in the functional material dispersion, the negatively charged functional material can be firmly combined with the part of the model formed by the photosensitive resin with positively charged groups through electrostatic action, thereby forming a functional material on the surface of the model. Constructed functionalized layers (eg, conductive layers). On the other hand, since the portion that does not need to be functionalized formed of neutral photosensitive resin has no electric charge, a functional material layer cannot be formed even if it is immersed in the functional material dispersion liquid, so that the selective functionalization of the model can be realized. .

The selective functionalization process of the model is exemplified with reference to Fig. 1, wherein Fig. 1(a) shows an interdigital electrode obtained by 3D printing by digital light processing, including the portion formed by neutral photosensitive resin that does not require functionalization 2 (substrate) and a schematic diagram of the model 1 of the part 3 (interdigital part) that needs to be functionalized formed from a photosensitive resin with a positively charged group; Figure 1(b) shows the model 1 immersed in the functional material dispersion 4; FIG. 1( c ) shows the finally obtained interdigital electrode with the functionalized layer 3 ′ formed on the surface. It should be noted that FIGS. 1( a ) to ( c ) are only examples for facilitating the understanding of the selective functionalization process of the present invention, and do not constitute a limitation on the protection scope of the present invention.

Example

The method and advantages of the present invention are further described below through the examples, but it should be known that the following examples are only examples of implementing the present invention, and do not constitute a limitation on the protection scope of the present invention.

Example 1

5 parts by mass of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide as a photoinitiator was added to 95 parts by mass of polyethylene glycol diacrylate, and shaken for 5 minutes using a shaker, After mixing evenly, stand for defoaming to obtain neutral photosensitive resin.

40 parts by mass of bisphenol A glycerol dimethacrylate (BisGMA), 30 parts by mass of triethylene glycol dimethacrylate, and 30 parts by mass of methacryloyloxyethyltrimethyl chloride The 80% aqueous solution of ammonium chloride was put into the beaker, stirred and mixed evenly with a glass rod, and then 5 parts by mass of phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide as a photoinitiator was added, and a magnetic force was used. The stirrer was stirred at a rotational speed of 800 rpm for 2 hours, and after thorough mixing, it was left to stand for defoaming to obtain a photosensitive resin with a positively charged group.

The model to be printed is designed and drawn by 3D modeling software and imported into the B9 Core 530DLP-3D printer. According to the design of the model, the neutral photosensitive resin prepared above and the photosensitive resin with positively charged groups are used for printing and curing. The wavelength of ultraviolet light was set to 405 nm and the exposure amount was set to 7 to obtain the desired model. After taking out the model, use anhydrous ethanol to clean the model to dissolve and remove the uncured monomer, and finally blow it with nitrogen and dry it.

Next, 0.3 g of carbon nanotubes (CNTs) and 0.4 g of sodium dodecyl sulfate were added to 100 g of deionized water, ultrasonically dispersed for 1 hour, and then left to stand to obtain a carbon nanotube dispersion, and the supernatant was taken for later use.

The cleaned 3D printed model was immersed in the above carbon nanotube dispersion (supernatant) for 30 minutes, then the model was taken out, rinsed with deionized water, blown with nitrogen, and dried.

In order to characterize the positively charged properties of the samples printed from the positively charged photosensitive resin and the negatively charged properties of the carbon nanotubes dispersed with an anionic dispersant, zeta tests at different pH (6, 7, 8) were carried out, respectively. Potential test, the results are shown in Figure 2. In Figure 2, the positive and negative values of the zeta potential value reflect the type of charge, and the magnitude of the absolute value reflects the amount of charge. It can be seen from Figure 2 that the zeta potential (solid line) of the samples printed from the positively charged photosensitive resin is positive and the absolute value is greater than 30mV, indicating that the surface has a certain amount of positive charges; carbon The zeta potentials of the nanotube dispersions (dotted lines in the figure) are all negative and the absolute value is greater than 20mV, indicating that the surface of the carbon nanotubes in the dispersion has a certain amount of negative charges. This result indicates the feasibility of using electrostatic adsorption to complete the selective functionalization.

The surface of the final DLP-3D printed model was characterized. The SEM image of Figure 3a shows the SEM image of the surface of the DLP-3D printed model after the selective functionalization of carbon nanotubes. In order to show the selectivity more clearly For functionalization, the EDS surface scan image characterization of S element was performed on the surface of the area photographed by SEM (Fig. 3b). S element is selected for EDS surface scanning because CNTs are dispersed by SDS (containing S), and SDS is wound around CNTs, so only the part where CNTs are adsorbed has S, so the EDS image of S can clearly reflect the situation of functionalization and Its selectivity, as can be seen from the EDS image of S element in Figure 3b, the right half contains a large amount of S element, indicating that a large number of carbon nanotubes are adsorbed on the surface, while the left half has only sporadic S element distribution and almost no carbon nanotubes. residue.

Example 2

A 3D printing model in which silver nanowires were selectively bound to the surface of the model was produced in the same manner as in Example 1, except that silver nanowires (AgNWs) were used as the functional material. Among them, as the nano-silver wire dispersion liquid, an isopropanol dispersion liquid having a concentration of 2.0 mass % of the nano-silver wire was used.

The SEM analysis of the final 3D printing model is carried out. It can be seen from Figure 4 that a selectively functionalized area (with AgNWs) and an unfunctionalized area (without AgNWs) are formed on the surface of the DLP-3D printed model, and the boundaries are clearly visible. It can be seen that, by the method of the present invention, the nano-silver wire layer can be selectively formed on the surface of the 3D printing model simply and conveniently.

Finally, it should be understood that the descriptions of the above-described embodiments and examples are illustrative in all respects and not restrictive, and various modifications can be made without departing from the spirit of the present invention. The scope of the present invention is indicated by the claims, not by the above-described embodiments or examples. In addition, the scope of the present invention includes all modifications within the meaning and scope equivalent to the claims.

Availability in Industry

The method for selectively functionalizing a digital light processing 3D printing model of the present invention is simple to operate, and can selectively functionalize the 3D printing model at low cost. The functionalized DLP-3D printing model obtained by the present invention has excellent electrochemical properties and mechanical properties, and such excellent properties have wide application prospects in the fields of 3D printing electronic device preparation, biomedicine, robotics and the like.

Claims (9)

1. A method of selectively functionalizing digital light processing 3D printing models, comprising: Prepare a neutral photosensitive resin containing a photocurable monomer (A); preparing a photosensitive resin with positively charged groups comprising a cationic monomer, a diluent and a photocurable monomer (B); Import the model to be printed into a digital light processing 3D printer, and print and cure the neutral photosensitive resin and the photosensitive resin with positively charged groups according to the design of the model to obtain a model; cleaning the obtained model to remove uncured monomers; Disperse the functional material in a solution containing an anionic surfactant to obtain a negatively charged functional material dispersion; The model is immersed in the functional material dispersion liquid, and taken out after a specified time, wherein the cationic monomer units in the model are dissociated in the functional material dispersion liquid and have a positive charge, which is related to the functional material dispersion liquid. The negatively charged functional materials in the material dispersion are combined by electrostatic adsorption, enabling the selective functionalization of the model. 2. The method for selectively functionalizing digital light processing 3D printing models according to claim 1, wherein the photocurable monomer (A) is selected from polyethylene glycol diacrylate, polyethylene glycol Alcohol dimethacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, and aliphatic monofunctional acrylates at least one. 3. The method for selectively functionalizing digital light processing 3D printing models according to claim 1, wherein the cationic monomer is selected from the group consisting of methacryloyloxyethyltrimethylammonium chloride, acryloyl Oxyethyltrimethylammonium chloride, methacryloylpropyltrimethylammonium chloride, acryloylpropyltrimethylammonium chloride, methacryloyloxyethylbenzyldimethylammonium chloride, and at least one of acryloyloxyethylbenzyldimethylammonium chloride. 4. The method for selectively functionalizing digital light processing 3D printing models according to claim 1, wherein the diluent is selected from the group consisting of diethylene glycol dimethacrylate and diethylene glycol diacrylate. , at least one of triethylene glycol dimethacrylate, triethylene glycol diacrylate, and tri(ethylene glycol) divinyl ether. 5. The method for selectively functionalizing digital light processing 3D printing models according to claim 1, wherein the photocurable monomer (B) is selected from the group consisting of bisphenol A glycerol dimethacrylate , Bisphenol A Glycerol Diacrylate, Ethoxylated Bisphenol A Diacrylate, Propoxylated Bisphenol A Diacrylate, Propoxylated Ethoxylated Bisphenol A Diacrylate, Ethoxylated Bisphenol A Diacrylate Any of the alkylated bisphenol A dimethacrylates. 6. The method for selectively functionalizing digital light processing 3D printing models according to claim 1, wherein the neutral photosensitive resin and the photosensitive resin with positively charged groups further comprise a photoinitiator, The photoinitiator is selected from phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, (2,4,6-trimethylbenzoyl)diphenylphosphine oxide, 1- At least one of hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, and benzoin anisole. 7. The method for selectively functionalizing digital light processing 3D printing models according to claim 1, wherein the anionic surfactant is sodium dodecyl sulfate, sodium dodecyl sulfate, hexadecyl At least one of sodium alkyl sulfonate. 8. The method for selectively functionalizing digital light processing 3D printing models as claimed in claim 1, wherein the functional material is any one of carbon nanotubes, graphene, nanosilver wires, and nanocopper wires . 9 . The method for selectively functionalizing a 3D printing model by digital light processing according to claim 1 , wherein when the model is immersed in the functional material dispersion, the immersion time is 10-30 minutes. 10 .

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