CN104804151A - Preparation method of light-cured resin material for three-dimensional printing - Google Patents

Abstract

The invention discloses a preparation method of a photocurable resin material for 3D printing. The steps include firstly synthesizing epoxy acrylic resin, then mixing it with a certain ratio of active diluent to obtain a uniform and stable composite organic solution, then adding a certain ratio of photoinitiator into the composite organic solution, heating and fully stirring to dissolve , and finally make a photocurable material for 3D printing. The method has the advantages of low cost, simple process, fast curing time and easy implementation.

Description

A kind of preparation method of photocurable resin material for 3D printing

technical field

The invention relates to a method for preparing a photocurable resin material for 3D printing, in particular to the preparation of the photocurable resin and its curing process under the action of a photoinitiator.

Background technique

3D printing technology is one of the most popular modern high-tech technologies. Its high precision and diversity of printable range make 3D printing rise rapidly in the manufacturing industry. Photocuring 3D printing technology is based on the principle of photopolymerization of liquid photosensitive resin. During the printing process, material injection and curing are carried out together. Stereo-curing 3D printing technology has more advantages than traditional melt extrusion 3D printing in terms of environmental protection and convenience. In view of the lack of domestic photocurable material formulations and the lack of shape in the technology industry, scientific researchers have done a lot of research work in this field, aiming to synthesize a photocurable material that meets the conditions of 3D printing and endow it with corresponding physical and chemical properties.

At present, most of the existing photocurable materials are concentrated in free radical photocurable resins, but the curing speed of this type of material is relatively slow, and it takes a long time to apply to 3D printing work; and the strength of the cured resin is relatively low , these two factors become the bottleneck of many existing formulations.

Lai Wenzhong and others used turpentine as the main raw material to react with maleic anhydride, epoxy fluoropropylene and acrylic acid to synthesize a new type of TMA epoxy acrylic resin. A UV-curable photosensitive resin is formed by adding a photosensitizer, an active initiator, and the like. The photosensitive resin is cured into a film in 1.4 minutes under ultraviolet light irradiation, and has excellent water resistance, oil resistance, chemical acid corrosion resistance, strong adhesion and good gloss. However, due to its long curing time, the entire manufacturing work time is lengthy, which greatly reduces the advantages of 3D printing.

The 3D printing of light-curing materials has high requirements on material performance. At a certain temperature, ensure that the printing material flows evenly; the curing time should be as fast as possible, and the curing shrinkage rate of the product after curing must not exceed 2%. In addition, many functional 3D printing materials also need to meet other related performance requirements, and most of the domestic formulations mainly have problems in the basic requirements of material performance, which makes it impossible to mass-produce and use, thus causing the original light-curing 3D printing technology. The phenomenon of stepping on the ground.

Contents of the invention

In view of the above-mentioned shortcomings, the present invention starts from the synthesis of epoxy acrylic resin, puts forward strict requirements on the ratio of photoinitiator and diluent, and makes the resin achieve the effect of rapid curing under the high-pressure mercury lamp light source.

Technical solution of the present invention and step are as follows:

(1) Weigh a certain amount of epoxy resin, dissolve it in toluene solvent, stir to dilute the solution, pour it into a three-necked flask, heat it in an oil bath at 85°C and stir to make it fully dissolved. In addition, accurately measure a certain amount of acrylic acid and place it in a beaker, and add the initiator N,N-xylidine and the polymerization inhibitor hydroquinone to make an acrylic acid system. In the epoxy resin, react stably for 1 hour, then gradually heat up to 95 ° C, and then react for 1 hour; after the reaction, the product is suction filtered and cooled to room temperature to obtain a light yellow transparent colloidal liquid, namely epoxy acrylic resin; The mass ratio of epoxy resin and acrylic acid is 2.8~3.4:1, the mass ratio of initiator N,N-xylidine and polymerization inhibitor hydroquinone is 3.5~4.5:1, the mass ratio of initiator and epoxy resin The ratio is 1:13~17;

(2) Weigh the epoxy acrylic resin, add reactive diluents N-vinylpyrrolidone and trimethylolpropane triacrylate, and stir the system fully until it is diluted. In order to make the resin have better sprayability and fluidity , the viscosity is adjusted to about 10 ^-14 centipoise by active diluent, and at the same time, it may be heated in a slight water bath to mix the substances evenly;

(3) Add photoinitiator benzoin dimethyl ether and benzophenone to the solution obtained in step (2) (wherein the mass ratio of epoxy acrylic resin, benzoin dimethyl ether and benzophenone is 2.7~3.3:0.95 ~1.05:1), put it in a water bath and heat up to dissolve, stir well, stop stirring when all the solid particles are dissolved, and cool to room temperature to obtain photocurable resin. It can be fully cured by irradiating under the high-pressure mercury lamp light source for about 1s.

The method for preparing the photocurable resin for 3D printing of the present invention is simple, easy to implement, and low in cost.

Description of drawings

Figure 1 is the liquid gel-like resin before photocuring.

Figure 2 shows the cured photocurable resin after being irradiated by a high pressure mercury lamp.

specific implementation plan

The following describes the specific implementation of a method for preparing a photocurable resin material for 3D printing according to the present invention, but it should be pointed out that the implementation of the present invention is not limited to the following implementation.

Example 1

Measure 25.94g of epoxy resin with an electronic balance, dissolve it in toluene solvent, stir to make the solution dilute, pour it into a three-necked flask, heat and stir in an oil bath at 85°C;

Measure 7.95g of acrylic acid and place it in a beaker, weigh 0.69g of initiator N,N-xylaniline, and 0.153g of polymerization inhibitor hydroquinone, add the two to acrylic acid to form an acrylic acid system, and stir thoroughly;

Add the above-mentioned acrylic acid system dropwise to the epoxy resin at 85°C, increase the stirring speed, and react stably for 1 hour, then gradually raise the temperature to 95°C, and react for another 1 hour. Suction filtration after completion of the reaction, cooling to room temperature, to obtain light yellow transparent colloidal liquid, namely epoxy acrylic resin;

Weigh 3g of epoxy acrylic resin, add 2.25g of N-vinylpyrrolidone and 1.04g of trimethylolpropane triacrylate, stir well until diluted, as shown in Figure 1;

Add 1.01 g of benzoin dimethyl ether and 1.04 g of benzophenone to the light-curable resin, place it in an oil bath to heat up and dissolve, and stir thoroughly. After all the solid particles are dissolved, stop stirring, and cool to room temperature to obtain the light-curable resin;

Spread the obtained light-cured resin evenly on the glass slide, and under the irradiation of a high-pressure mercury lamp, it can be completely cured in about 1 second. The effect after complete curing is shown in Figure 2.

Example 2

Measure 26.26g of epoxy resin with an electronic balance, dissolve it in toluene solvent, stir to make the solution dilute, pour it into a three-necked flask, heat it in an oil bath at 85°C, and place it on a magnetic stirring bar to stir;

Measure 8.19g of acrylic acid and place it in a beaker, weigh 0.88g of initiator N,N-xylaniline, and 0.173g of polymerization inhibitor hydroquinone, add the two to acrylic acid to form an acrylic acid system, and stir thoroughly;

Add the above-mentioned acrylic acid system dropwise to the epoxy resin at 85°C, increase the magnetic stirring speed, and react stably for 1 hour, then gradually raise the temperature to 95°C, and react stably for 1 hour. Suction filtration after completion of the reaction, cooling to room temperature, to obtain light yellow transparent colloidal liquid, namely epoxy acrylic resin;

Weigh 3g of epoxy acrylic resin, add 2.05g of N-vinylpyrrolidone, 1.04g of trimethylolpropane triacrylate, and fully stir until diluted;

Add 1.07 g of benzoin dimethyl ether and 1.10 g of benzophenone to the photocurable resin, place it in an oil bath to heat up and dissolve, and stir thoroughly. After all the solid particles are dissolved, stop stirring and cool to room temperature to obtain the photocurable resin;

Spread the obtained light-cured resin evenly on the glass slide, and under the irradiation of a high-pressure mercury lamp, it can be completely cured in about 1 second.

Claims (1)

1. prepare a method for 3D printing photocurable resin material, it is characterized in that comprising the steps:

(1) take a certain amount of epoxy resin, be dissolved in toluene solvant, stir and make solution be dilution shape, pour there-necked flask into and be placed on 85 DEG C of oil baths and heat and stir, make it fully dissolve; Accurately measured amounts vinylformic acid is placed in beaker in addition, and add initiator N, N-xylidene(s), hydroquinone of polymerization retarder are made into acrylic system, after abundant stirring, aforesaid propylene acid system is dropwise instilled in the epoxy resin of 85 DEG C, stablize reaction 1 hour, be then progressively warming up to 95 DEG C, then react 1 hour; Reaction terminates after product and carries out suction filtration, is cooled to room temperature, obtains light yellow clear colloidal liquid, i.e. epoxy acrylic resin; Its epoxy resin and acrylic acid mass ratio are 2.8 ~ 3.4: 1, and the mass ratio of initiator N, N-xylidene(s) and hydroquinone of polymerization retarder is 3.5 ~ 4.5: 1, and the mass ratio of initiator and epoxy resin is 1: 13 ~ 17;

(2) epoxy acrylic resin is taken, add reactive thinner NVP and Viscoat 295, make system be stirred well to dilution shape, in order to make resin possess better can ejection and mobility, by reactive thinner, system viscosity is adjusted to 10 ^-14about centipoise, simultaneously or can slight heating in water bath, make to mix between each material;

(3) light trigger benzoin dimethylether and benzophenone (wherein the mass ratio of epoxy acrylic resin, benzoin dimethylether, benzophenone is 2.7 ~ 3.3: 0.95 ~ 1.05: 1) is added in the solution obtained to step (2), be placed in water-bath rising temperature for dissolving, abundant stirring, treat that solid particulate matter all dissolves, stop stirring, be cooled to room temperature, namely obtain light-cured resin, under high voltage mercury lamp light source, irradiate about 1s Ke Da solidify completely.