CN119684533A - Ultraviolet light curing resin composition and preparation method thereof - Google Patents

Abstract

A UV-curable resin composition and a preparation method thereof. The resin composition consists of a resin solution and coupled-treated ground fibers. By adding the ground fibers, the mechanical properties, impact strength and wear resistance of the material are improved, the porosity of the printed part is reduced, and the warping problem of the printed model is improved.

Description

Ultraviolet light curing resin composition and preparation method thereof

Technical Field

The invention relates to the technical field of additive manufacturing, in particular to an ultraviolet light curing resin composition and a preparation method thereof.

Background

The additive manufacturing technology is a technology for directly manufacturing three-dimensional objects layer by layer through computer three-dimensional control software or three-dimensional printing equipment. The molding methods can be classified into fused deposition molding technology, stereolithography technology, photopolymer injection technology, powder laser sintering, stereolithography technology, and the like. The three-dimensional photo-curing forming technology is a better additive manufacturing technology at present. The technology uses ultraviolet sensitive liquid resin as a raw material, and utilizes photopolymerization to scan and cure the liquid resin layer by layer to realize layer by layer molding. The technology is widely applied to various fields such as aerospace manufacturing, automobile manufacturing, bioengineering, integrated device manufacturing and the like. The technology has the characteristics of simple, quick and economical manufacture.

Printing consumables are key to influence the performance and application of devices, the photosensitive resin which is dominant in the market at present is mainly high-strength photosensitive resin, but because the polymer after the material is cured is high in crosslinking density, the flexibility of a formed part is poor, the impact resistance is poor, the formed part is extremely easy to break under the action of external force, and the application is limited. The flexible resin developed in the current market has low strength, easy deformation, poor molding degree, and the molded part is not folded and has low curing degree.

Curing shrinkage and warpage have been relatively problematic in light curing techniques. Taking the mechanism of the photo-curing free radical polymerization process as an example, the photo-curing reaction is completed instantaneously, the internal stress caused by curing shrinkage is difficult to release in time, the defect and the warpage of the material are extremely easy to cause, the service performance and the stability of the material are reduced, and the influence on the dimensional accuracy of a printed product is large.

CN201711136900.9 discloses a novel 3D printing resin with rapid solidification and low shrinkage, which comprises 40-50 parts of polyurethane acrylate prepolymer, 10-30 parts of reactive diluent, 1-5 parts of photoinitiator and 0.1-10 parts of auxiliary agent. The 3D printing resin is mainly composed of resin, and the resin material has the characteristics of high brittleness, poor toughness, easy shrinkage of the resin and low application value in actual production.

CN201810531974.0 discloses a photo-thermal dual-curing 3D printing resin composition, comprising 66-86 parts of free radical type photosensitive resin, 9-29 parts of thermosetting epoxy resin, 1-4 parts of free radical type photoinitiator and 1-3 parts of latent type thermosetting agent. The invention adopts photo-thermal dual-curing mode molding, has more complicated steps and higher actual production cost, and has no report on mechanical properties.

CN201810480617.6 discloses an environment-and human-friendly vegetable oil-based uv-curable 3D printing resin comprising palm oil polyester acrylate based on palm oil, epoxidized soybean oil Acrylate (AESO) based on soybean oil, glucose Oxidase (GOX), a radical initiator, an auxiliary agent, a reactive diluent, polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB). The effect that the 3D printing finished product is biodegradable is achieved. The advantages are degradability, environmental friendliness, low tensile strength and not suitable for some industries with high requirements.

CN201910190173.7 discloses a high-strength high-temperature-resistant 3D printing resin, which comprises 10-30 parts of rigid alicyclic epoxy resin, 15-25 parts of flexible alicyclic epoxy resin, 40-70 parts of prepolymer, 10-18 parts of oxetane reactive diluent, 1-3 parts of functionalized nano particles, 1-3 parts of color additive, 1-2 parts of solubilizer, 5-10 parts of unsaturated polyester resin, 0.5-1 part of ammonium isocyanate, 5-8 parts of polycarbonate, 5-7 parts of copper naphthenate powder and 2-5 parts of diethyl phthalate. The invention mentions that it has good mechanical strength, but no data are reported. And the pure resin material is generally larger in curing shrinkage and poorer in impact toughness.

CN201911084468.2 discloses a DLP type photo-curing 3D printing resin, which comprises mercapto carboxylic ester compounds, allyl or triacrylate compounds, urethane acrylate, photoinitiator, diluent, defoamer and antioxidant. The 3D printing spline has the bending strength of 95MPa and the tensile strength of 53MPa, and is limited in practical application.

CN201911311274.1 discloses a photosensitive resin containing micro-nano wax powder, the photosensitive resin comprises 0.1% -5% of photoinitiator, 0.05% -2% of ultraviolet absorber, 0.15% -3% of dispersing agent, 0.001% -0.5% of color auxiliary agent, 0.1% -2% of coupling agent, 0.01% -0.05% of defoamer, 5% -85% of active monomer, 5% -90% of micro-nano wax powder and 10% -80% of active oligomer. The method has complicated steps and has no related report on mechanical strength.

CN202010024437.4 discloses an ultraviolet curing elastic resin for 3D printing, which comprises 5-15 parts of carboxyl-terminated butadiene modified polyurethane acrylic ester, 25-60 parts of active monomer, 0.01-0.2 part of polymerization inhibitor, 1-10 parts of photoinitiator, 0.02-1 part of defoamer, 0.02-1 part of flatting agent, 0.03-2 parts of pigment and 2-5 parts of filler. The tensile strength of the prepared material is 25.65MPa, and the elongation at break is 190%. The method has the advantages of certain elasticity, complex steps and long production period.

CN202010346027.1 discloses a soft photo-curing 3D printing resin material, which comprises 30-50 parts of oligomer, 40-60 parts of monomer, 0.1-6 parts of photoinitiator and 0-4 parts of auxiliary agent, wherein the auxiliary agent comprises UV color paste, leveling agent, defoaming agent, dispersing agent, ultraviolet absorbent, sensitizer, polymerization inhibitor and inorganic filler. The 3D printing resin material has good folio resistance of a printed and molded product, and has the defect of low tensile strength.

CN202111201955.X discloses a hollow porous silica microsphere reinforced photo-curing 3D printing composite material, which comprises 40-55 parts of acrylate resin prepolymer, 45-55 parts of reactive diluent monomer, 1-2 parts of photoinitiator, 0.05-0.1 part of ultraviolet absorber and 0.1-10 parts of hollow porous silica, wherein the acrylate resin prepolymer is a mixture of 55-65 parts of aliphatic polyurethane acrylate and 35-45 parts of aromatic polyurethane acrylate according to mass fraction. The cured material has good mechanical properties, but has higher curing shrinkage.

CN202011398158.0 discloses a chopped quartz fiber reinforced silica ceramic paste for photo-curing, which is prepared by firstly preparing a bundle of chopped quartz fibers into a monofilament chopped quartz fiber, then mixing SiO ₂ powder with a powder dispersing agent, performing ball milling treatment by a ball mill, adding a photo-initiator and a silane coupling agent into a resin mixed solution, performing ball milling to obtain a photo-curing resin system, adding the photo-curing resin system into a solid mixture, simultaneously dripping a light absorber, stirring and placing into a homogenizing mixer for mixing and vacuumizing, finally adding the monofilament chopped quartz fibers into the silica ceramic paste for uniformly mixing to obtain the ceramic paste, wherein the mechanical strength of the resin paste is not reported.

CN202011397781.4 discloses a pre-treated dual-curing 3D printing resin, comprising 19% -78% of oligomer, 1% -9% of free radical initiator, 0.5% -5% of cationic initiator, 0.5% -5% of hybrid curing photoinitiator, 0.2% -4% of auxiliary agent, 10% -35% of reactive diluent, 13% -62% of cationic monomer and 5% -20% of hybrid monomer. The printing resin has low shrinkage, good curing performance and excellent mechanical property. But pure resin materials are generally less ductile.

CN202111587812.7 discloses a novel photocuring 3D printing resin material, the molecular chain structure of the resin material is dendritic, the main chain is polyacrylate, the side chain comprises an acrylic ester group and a modified organic silica flexible long chain, a fluorine-containing active monomer and a fluorine-containing organic toughening agent are introduced into a crosslinked network, and the novel photocuring 3D printing resin material comprises 30-50 parts of acrylic ester, 5-20 parts of an organic silica active chain, 30-50 parts of an active diluent, 0.5-4 parts of a free radical photoinitiator and 0.05-4 parts of an auxiliary agent. The material has good printing toughness, curing shrinkage and low warping.

CN202110554184.6 discloses a water-based ultraviolet light curing resin, which has two ammonium salt hydrophilic groups, water can be directly added into the resin to dilute the resin, and the resin has the characteristic of fast curing speed through ultraviolet light irradiation curing, but no report is made on mechanical properties.

CN202211619791.7 discloses a UV light-cured 3D printing resin, which is prepared by sequentially adding an anhydride compound, a polymerization inhibitor, hydroxy acrylic ester and a catalyst into a reaction kettle, stirring for 1-12h at 50-120 ℃, then adding bisphenol A epoxy resin, the catalyst and the polymerization inhibitor, and finally adding an acrylic ester monomer. The product has high curing speed, good toughness and low shrinkage.

JP-A9-151223 discloses a photo-setting resin composition comprising urethane (meth) acrylate, N-vinylamide monomer, photoinitiator, etc., the tensile strength of the prepared material is only 0.8kgf/mm ² at maximum.

CN202310651518.0 discloses an organic-inorganic composite 3D printing resin, which comprises, by weight, 10-30 parts of organosilicon modified polyurethane acrylic resin, 55-85 parts of small molecule reactive diluents, 5-30 parts of shell powder and 4-6 parts of free radical photoinitiators. The printing resin has the characteristics of low shrinkage, high precision and high strength.

CN202310452296.X discloses a superhard dental model photo-curing 3D printing resin material, which comprises 40-60 parts of reactive diluent monomer, 40-60 parts of polyurethane acrylate oligomer, 1-3 parts of photoinitiator and 3-5 parts of hydrophobically modified titanium dioxide nanomaterial. The resin material has low viscosity, high curing speed and certain strength and toughness.

Based on the analysis, the ultraviolet light curing resin composition is provided, and is applied to the field of three-dimensional additive manufacturing, so that the ultraviolet light curing resin composition has the characteristics of excellent mechanical property strength, high toughness, high wear resistance, low porosity and low warpage, and has great application value.

Disclosure of Invention

The invention aims to solve the technical problems of overcoming the defects of the prior art and providing an ultraviolet light curing resin composition and a preparation method thereof, wherein the mechanical property, impact strength and wear resistance of a material are improved, the porosity of a printed part is reduced, and the warping problem of a printing model is improved by adding grinding fibers. In order to overcome the defects in the prior art, the invention aims to provide an ultraviolet light curing resin composition and a preparation method thereof, and the ultraviolet light curing resin composition has the characteristics of low porosity, high toughness, high wear resistance and the like.

In order to solve the technical problems, the invention adopts the following technical scheme.

The invention firstly provides an ultraviolet light curing resin composition which comprises a component A and a component B,

The component A is a resin solution, and comprises 40-50 parts by weight of acrylate resin oligomer, 50-70 parts by weight of reactive diluent monomer, 5-10 parts by weight of structure stabilizer, 0.5-5 parts by weight of photoinitiator, 0.5-5 parts by weight of ultraviolet absorber and 0.5-5 parts by weight of defoamer;

the component B is a grinding fiber subjected to coupling treatment;

The weight ratio of the component A to the component B is (80-55) (20-45) based on 100 parts by weight of the total of the component A and the component B.

Further, the weight ratio of component A to component B is (70-60): (30-40), or 65:35, based on 100 parts by weight of the total of component A and component B.

Further, the acrylate resin oligomer is at least one selected from epoxy acrylate, urethane acrylate, polyester acrylate and polyether acrylate.

Further, the urethane acrylic functionality is 8-13, or 9 or 10 or 11 or 12.

Further, the weight parts of the acrylate resin oligomer are 42 parts, 45 parts, 48 parts.

Further, the reactive diluent monomer is at least one of hydroxyethyl methacrylate, isobornyl acrylate, tripropylene glycol diacrylate, 1, 6-hexanediol diacrylate and trimethylolpropane triacrylate.

Further, the functionality of the reactive diluent monomer is less than or equal to 3, or is 2 or 1.

Further, the weight parts of the reactive diluent monomer are 55 parts, 60 parts and 65 parts.

Further, the structure stabilizer is at least one of polyvinyl alcohol, cellulose ether, chitosan, calcium stearate and carboxymethyl cellulose sodium salt.

Further, the weight parts of the structure stabilizer are 6 parts, 8 parts and 9 parts.

Further, the photoinitiator is at least one of 2,4, 6-trimethylbenzoyl-diphenyl phosphine oxide (TPO) and 1-hydroxy cyclohexyl phenyl ketone (Irgacure-184).

Further, the weight parts of the photoinitiator are 1 part, 1.5 parts, 2 parts, 3 parts and 4 parts.

Further, the ultraviolet absorber is one or more of benzotriazole, substituted acrylonitrile, triazine, salicylate and benzophenone ultraviolet absorbers.

Further, the diphenyl ketone ultraviolet absorber is at least one of 2, 4-dihydroxydiphenyl ketone (BP-1) and 2-hydroxy-4-methoxyl diphenyl ketone (BP-3).

Further, the weight parts of the ultraviolet absorber are 1 part, 1.5 parts, 2 parts, 3 parts and 4 parts.

Further, the defoaming agent is one or more of an alcohol defoaming agent, an organic silicon resin defoaming agent and a polyether modified silicone oil defoaming agent.

Further, the defoamer is at least one of BYK055, BYK088, BYK020 and BYK 067A.

Further, the weight parts of the defoamer are 1 part, 1.5 parts, 2 parts, 3 parts and 4 parts.

Further, the grinding fiber is an inorganic fiber and comprises at least one of grinding glass fiber, grinding asbestos fiber, grinding carbon fiber, grinding alumina fiber, grinding zirconia fiber, grinding silicon carbide fiber, grinding aluminum silicate fiber, grinding silicon nitride fiber, grinding graphene fiber and grinding basalt fiber.

Further, the abrasive fiber has a diameter of 5 to 9 μm, or 6 μm, 7 μm, 8 μm, and a length of 50 to 200 μm, or 80 μm, 100 μm, 150 μm.

Further, the ground fiber is subjected to degreasing treatment and coupling agent treatment.

Further, the degreasing treatment of the grinding fiber is carried out, the grinding fiber is placed in a high-temperature furnace protected by inert gas, and the degreasing treatment is carried out at the high temperature of 400-1400 ℃ (or 600 ℃, 800 ℃,1000 ℃ and 1200 ℃) for 0.5-6h (or 1h, 2h and 4 h).

Furthermore, the inert gas is high-purity nitrogen or high-purity argon, and the purity is more than or equal to 99.99%.

Further, the coupling agent treatment of the grinding fiber is carried out, the grinding fiber, the solvent and the coupling agent are mixed, refluxed and dried, and the surface modified grinding fiber is obtained.

Further, the coupling agent is at least one of a silane coupling agent, a titanate coupling agent and an aluminate coupling agent.

Preferably, at least one of silane coupling agents KH550, KH560, KH570, KH580, KH590, KH151, KH171, KH172 is used.

Further, the mass ratio of the grinding fiber to the solvent to the coupling agent is (80-110): (80-110): (0.2-3).

Further, the temperature of the reflux is 70-100 ℃, or 80 ℃ or 90 ℃, and the time of the reflux is 4-6h, or 5h.

The invention also provides a preparation method of the resin composition for photo-curing, which comprises the following steps:

step (1), grinding fiber modification treatment

Refluxing the grinding fiber, the solvent and the coupling agent to obtain the coupling-treated grinding fiber;

step (2) of preparing a resin solution

Mixing an acrylic resin oligomer, a reactive diluent monomer, a structure stabilizer, a photoinitiator, an ultraviolet absorber and a defoaming agent, and uniformly stirring to obtain a resin solution;

step (3) of preparing a resin composition

Mixing the modified grinding fiber obtained in the step (1) and the resin solution obtained in the step (2), and carrying out rotary treatment in an internal mixer to obtain the resin composition.

Further, in the step (1), the ground fiber is subjected to degreasing treatment and then is subjected to coupling treatment;

Further, in the step (1), the degreasing treatment of the grinding fiber is carried out, the grinding fiber is placed in a high-temperature furnace protected by inert gas, and the degreasing treatment is carried out at the high temperature of 400-1400 ℃ or 600 ℃, 800 ℃, 1000 ℃ or 1200 ℃ for 0.5-6h (or 1h, 2h or 4 h).

Further, in the step (1), further, the coupling agent treatment of the grinding fiber is carried out, the grinding fiber, the solvent and the coupling agent are mixed, refluxed and dried, and the surface modified grinding fiber is obtained.

Further, in the step (1), the coupling agent is at least one of a silane coupling agent, a titanate coupling agent and an aluminate coupling agent.

Preferably, at least one of silane coupling agents KH550, KH560, KH570, KH580, KH590, KH151, KH171, KH172 is used.

Further, in the step (1), the mass ratio of the grinding fiber, the solvent and the coupling agent is (80-110): 0.2-3.

Further, in the step (1), the temperature of the reflux is 70-100 ℃, or 80 ℃ or 90 ℃, and the time of the reflux is 4-6 hours, or 5 hours.

Further, in the step (2), the acrylate resin oligomer is at least one selected from epoxy acrylate, polyurethane acrylic resin, polyester acrylate and polyether acrylate.

Further, in step (2), the urethane acrylic resin has a functionality of 8 to 13, or 9 or 10 or 11 or 12.

Further, in the step (2), the reactive diluent monomer is at least one of hydroxyethyl methacrylate, isobornyl acrylate, tripropylene glycol diacrylate, 1, 6-hexanediol diacrylate and trimethylolpropane triacrylate.

Further, in the step (2), the functionality of the reactive diluent monomer is less than or equal to 3, or is 2 or 1.

Further, in the step (2), the structure stabilizer is at least one of polyvinyl alcohol, cellulose ether, chitosan, calcium stearate and carboxymethyl cellulose sodium salt.

Further, in the step (2), the photoinitiator is at least one of 2,4, 6-trimethylbenzoyl-diphenyl phosphine oxide (TPO) and 1-hydroxy cyclohexyl phenyl ketone (Irgacure-184).

Further, in the step (2), the ultraviolet absorbent is one or more of benzotriazole, substituted acrylonitrile, triazine, salicylate and benzophenone ultraviolet absorbent.

Further, in the step (2), the diphenyl ketone ultraviolet absorber is at least one of 2, 4-dihydroxydiphenyl ketone (BP-1) and 2-hydroxy-4-methoxyl diphenyl ketone (BP-3).

Further, in the step (2), the defoaming agent is one or more of an alcohol defoaming agent, a silicone resin defoaming agent and a polyether modified silicone oil defoaming agent.

Further, in the step (2), the defoamer is at least one of BYK055, BYK088, BYK020 and BYK 067A.

Further, in the step (3), the weight ratio of the resin solution to the abrasive fiber (B) is (80-55): 20-45, based on 100 parts by weight of the total of the resin solution (A) and the abrasive fiber (B).

Further, in the step (3), the weight ratio of A to B is (70-60): (30-40), or 65:35, based on 100 parts by weight of the total of A and B.

Further, in the step (3), the rotating speed of the rotating treatment in the internal mixer is set to be 2000-3000r/min, and the rotating time is set to be 4-6h.

Further, the viscosity of the resin composition is 100 to 600 mPas.

Further, the invention provides a preparation method of the ultraviolet light curing resin composition, which comprises the following steps:

Placing the grinding fiber in a high-temperature furnace protected by high-purity nitrogen, degreasing at 400-1400 ℃ for 0.5-6h, cooling to room temperature, and kneading to obtain the monofilament grinding fiber for standby, performing ultrasonic dispersion on the monofilament grinding fiber, absolute ethyl alcohol and a silane coupling agent according to the mass ratio of 100:100 (0.5-2), pouring the dispersed suspension into a three-neck flask, condensing and refluxing in a water bath kettle at 80 ℃ for 4-6h, drying in nitrogen atmosphere to obtain the surface modified grinding fiber for standby, and performing contact angle test on a small amount of grinding fiber before and after modification;

and (2) adding 50 parts by weight of reactive diluent monomer into 40 parts by weight of resin, stirring and mixing, adding 5 parts by weight of structural stabilizer, 1 part by weight of photoinitiator, 1.5 parts by weight of ultraviolet absorbent and 1 part by weight of defoamer, and mixing to obtain a resin solution, wherein the stirring speed is set to 1000-2000r/min, and the stirring time is set to 1-3h.

And (3) placing the surface modified grinding fiber prepared in the step (1) and the resin solution prepared in the step (2) into an internal mixer according to the weight ratio of (20-45) (80-55), wherein the parameters are set to be circulation of forward rotation for 0.5h and reverse rotation for 0.5h, the rotating speed is set to be 2000-3000r/min, and the rotating time is set to be 4-6h, so that the light-cured grinding fiber reinforced resin composition is obtained, and the viscosity of the resin composition is 100-600 mPa.s.

Furthermore, the step (2) and the step (3) are prepared under dark conditions.

The invention also provides application of the ultraviolet light curing resin composition in three-dimensional printing.

The invention also provides application of the grinding fiber in three-dimensional printing, wherein the grinding fiber is the coupling-treated grinding fiber.

Compared with the prior art, the product provided by the invention has the following advantages or functions:

The grinding fiber has good wear resistance and toughness, and the surface of the grinding fiber is modified by the treatment of the coupling agent, so that the grinding fiber has good dispersibility in a resin system. The wear resistance and toughness of the resin composition can be improved by controlling the quantity of the added grinding fibers, the long-time stability of the resin composition can be ensured by adding the structural stabilizer, and meanwhile, the ultraviolet light curing resin composition is prepared by matching with reasonable process conditions. The invention has the advantages of easily obtained raw materials, lower cost, feasible process route and high compactness of the prepared sample, and is suitable for industrial production.

Drawings

FIG. 1 is a schematic illustration of a reaction process for crosslinking milled fibers and a polymer resin into an organic-inorganic hybrid three-dimensional network by a coupling agent;

FIG. 2 is a scanning electron microscope image of the resin composition after curing.

Detailed Description

For a better understanding of the present invention, its construction, and the functional features and advantages attained by the same, reference should be made to the accompanying drawings in which:

FIG. 1 is a schematic illustration of a reaction process for crosslinking milled fibers and a polymer resin into an organic-inorganic hybrid three-dimensional network by a coupling agent;

FIG. 2 is a scanning electron microscope image of the resin composition after curing.

The invention provides a preparation method of a low-shrinkage, high-toughness and high-wear-resistance resin composition, which comprises the following steps:

Placing the grinding fiber into a high-temperature furnace protected by high-purity nitrogen or high-purity argon with the purity of more than or equal to 99.99%, degreasing at 400-1400 ℃ for 0.5-6h, cooling to room temperature, and rubbing to obtain the monofilament grinding fiber for standby, performing ultrasonic dispersion on the monofilament grinding fiber, absolute ethyl alcohol and a silane coupling agent according to the mass ratio of 100:100 (0.5-2), pouring the dispersed suspension into a three-neck flask, condensing and refluxing in a water bath kettle with the temperature of 80 ℃ for 4-6h, drying in nitrogen atmosphere to obtain surface modified grinding fiber, and performing contact angle test on a small amount of grinding fiber before and after modification for standby;

And (2) adding 50 parts by weight of reactive diluent monomer into 40 parts by weight of resin, stirring and mixing, and simultaneously adding 5 parts by weight of structural stabilizer, 1 part by weight of photoinitiator, 1.5 parts by weight of ultraviolet absorber and 1 part by weight of defoamer and mixing to obtain a resin solution. Setting stirring speed at 1000-2000r/min and stirring time at 1-3h.

And (3) placing the surface modified grinding fiber prepared in the step (1) and the resin solution prepared in the step (2) into an internal mixer according to the weight ratio of (20-45) to (80-55), further placing the surface modified grinding fiber and the resin solution into the internal mixer according to the weight ratio of (30-40) to (70-60), setting parameters of the surface modified grinding fiber and the resin solution to be forward rotating for 0.5h and reverse rotating for 0.5h, setting the rotating speed to be 2000-3000r/min, and setting the rotating time to be 4-6h, thus obtaining the ground fiber reinforced resin composition for photocuring.

The viscosity of the resin composition is 100-600 mPas, and further the viscosity of the resin composition is 300-500 mPas.

Test bars were prepared by irradiating the resin composition of the present invention and the comparative resin composition with a laser beam having a wavelength of 285 to 415nm for 3 to 5 minutes under curing conditions.

The material testing equipment or the testing method provided by the invention are described as follows:

1. contact angle was measured using a contact angle measuring instrument of CA-100B from the company finuo.

2. Viscosity was measured using a Bowler's DVS+ rotational viscometer.

3. Porosity the porosity is performed with reference to the GB/T25995-2010 standard.

4. Tensile Properties were carried out with reference to the GB/T23805 standard. The test was carried out on a mechanical property tester with a loading rate of 0.5mm/min. The spline size (width. Times. Thickness) was 10 mm. Times.4 mm, and the number of 10 bars was averaged.

5. Bending performance is performed with reference to the GB/T9341-2008 standard. The test was carried out on a mechanical property tester with a loading rate of 0.5mm/min. The spline dimensions (length. Times. Width. Times. Thickness) were 36 mm. Times. 4 mm. Times. 3mm, span 30mm, number 10, and averaged.

6. Fracture toughness the fracture toughness is tested by adopting a single-side notched beam method (SENB) and the test is carried out on a mechanical property tester, and the loading rate is 0.5mm/min. The spline dimensions (length. Times. Width. Times. Thickness) were 50 mm. Times.3.5 mm. Times.7 mm, the intermediate incision depth was 3.5mm (thickness direction), the span was 30mm, and the number of 10 bars was averaged.

Example 1

An ultraviolet light curable resin composition and a method for preparing the same, comprising:

step (1) grinding fiber modification treatment

Placing the ground carbon fiber in a high-temperature furnace with the high-purity argon gas protection of 99.99%, degreasing at 1200 ℃ for 30min, cooling to room temperature, and rubbing to obtain the monofilament ground carbon fiber for later use, mixing 100 parts by weight of the monofilament ground carbon fiber, 100 parts by weight of absolute ethyl alcohol and 0.5 part by weight of silane coupling agent KH171, performing ultrasonic dispersion, pouring the dispersed suspension into a three-neck flask, condensing and refluxing for 4h in an 80 ℃ water bath kettle, drying in nitrogen atmosphere to obtain surface-modified ground carbon fiber, placing into a drying box for later use, and taking a small amount of ground carbon fiber before and after modification for contact angle test;

step (2) preparation of resin solution

Under the condition of avoiding light, 50 parts by weight of trimethylolpropane triacrylate monomer is added into 40 parts by weight of 8-functionality polyurethane acrylic resin, stirred and mixed, and 5 parts by weight of carboxymethyl cellulose sodium salt serving as a structural stabilizer, 1 part by weight of photo-initiator TPO, 1.5 parts by weight of ultraviolet absorbent BP-1 and 1 part by weight of defoamer BYK055 are added and mixed to obtain a resin solution. Setting stirring speed to 1500r/min, and stirring for 1h until the solution is uniformly mixed.

Step (3) preparation of the resin composition

And (3) under the light-shielding condition, placing the surface modified ground carbon fiber prepared in the step (2) and the resin solution prepared in the step (3) into an internal mixer according to the weight ratio of 35:65, wherein the parameters are set to be circulation of forward rotation for 0.5h and reverse rotation for 0.5h, the rotating speed is set to 2500r/min, and the rotating time is set to 4h, so that the ground fiber reinforced resin composition for photocuring is obtained.

Example 2

The difference from example 1 is that the silane coupling agent KH171 was added in a proportion of 1 part by weight in the first-step carbon fiber-grinding modification treatment of example 2.

Example 3

The difference from example 1 is that the weight ratio of the surface-modified milled carbon fiber to the resin solution in the third step of the resin composition preparation of example 3 is 30:70.

Example 4

The difference from example 1 is that the weight ratio of the surface-modified milled carbon fiber to the resin solution in the third step of the resin composition preparation of example 4 is 40:60.

Example 5

The difference from example 1 is that the silane coupling agent in the first step of the carbon fiber modification treatment was KH550.

Example 6

The difference from example 1 is that the first step milled fiber of example 6 is milled glass fiber, the treatment temperature is 600 ℃ for 0.5h.

Comparative example 1

The difference from example 1 is that the first-step milled fiber of comparative example 1 was not added with the silane coupling agent KH171.

Comparative example 2

The difference from example 1 is that the surface-modified abrasive fiber was not added in the preparation of the third-stage resin composition of comparative example 2.

Comparative example 3

The difference from example 1 is that the weight ratio of the surface-modified milled carbon fiber to the resin solution in the third step of the resin composition preparation of comparative example 3 was 65:35.

Test bars were prepared under curing conditions of contact angle data before and after modification of the modified fiber of the present invention, viscosities of the resin composition and the comparative resin composition, and irradiation of laser beam at 415nm wavelength for 5min, and mechanical properties after curing were measured as shown in table 1.

TABLE 1 modified abrasive fiber Water drop angle, resin composition viscosity, test piece porosity after curing, and mechanical property data

From the test results of the above examples and comparative examples, it can be seen that the contact angle of the milled fiber after modification becomes large and the hydrophobicity is enhanced. Examples 1 to 5 have better mechanical properties and lower porosity than comparative examples 1 to 3. The silane coupling agent is properly added to modify the surface of the grinding fiber, so that the grinding fiber can be well dispersed in a resin system, has good bonding effect with the resin, and is favorable for improving mechanical properties. The proportion of the grinding fiber and the resin has better mechanical property in a certain range, the proportion of the grinding fiber is too low, and the brittleness of the material is high, so that the mechanical property can be deteriorated. The proportion of the grinding fibers is too high, the degree of wrapping part of the grinding fibers by the resin matrix is low, and the load cannot be effectively transmitted to the fibers, so that the mechanical properties are reduced. Example 6 has lower mechanical strength than example 1, which indicates that the mechanical properties of the material are different when different abrasive fibers are added, but the mechanical properties are improved compared with those of the material without abrasive fibers. The inorganic fiber material has the characteristics of strong wear resistance and good flexibility, and the wear resistance and the flexibility of the material can be greatly improved by adding the inorganic fiber into the resin. The embodiment provided by the invention relates to an ultraviolet curing resin composition and a preparation method thereof, wherein the resin material with low porosity, high toughness and high wear resistance is prepared by controlling the types and the proportion of additives and adopting reasonable process conditions. The fiber is ground by modifying with the coupling agent, so that the dispersibility and compatibility of the fiber in a resin system can be improved, and the prepared resin composition can maintain uniformity and stability for a long time. The material disclosed by the invention is low in cost, simple in preparation process, suitable for batch production, and capable of solving the problems of large shrinkage, low strength, poor toughness and poor wear resistance of the existing three-dimensional printing material.

The foregoing description is only of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. All equivalent changes and modifications made in accordance with the present invention are intended to be covered by the scope of the appended claims.

Claims (20)

1. A UV-curable resin composition comprising component A and component B, Component A is a resin solution, comprising 40-50 parts by weight of an acrylate resin oligomer, 50-70 parts by weight of an active diluent monomer, 5-10 parts by weight of a structural stabilizer, 0.5-5 parts by weight of a photoinitiator, 0.5-5 parts by weight of an ultraviolet absorber, and 0.5-5 parts by weight of a defoamer; Component B is a coupling-treated ground fiber; Based on 100 parts by weight of component A and component B in total, the weight ratio of component A to component B is (80-55):(20-45). 2 . The resin combination according to claim 1 , wherein the acrylate resin oligomer is selected from at least one of epoxy acrylate, polyurethane acrylate, polyester acrylate, and polyether acrylate. 3. The resin combination according to claim 2, characterized in that the functionality of the polyurethane acrylic resin is 8-13. 4. The resin combination according to claim 1, characterized in that the active diluent monomer is at least one of hydroxyethyl methacrylate, isobornyl acrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, and trimethylolpropane triacrylate. 5 . The resin combination according to claim 1 , wherein the structural stabilizer is at least one of polyvinyl alcohol, cellulose ether, chitosan, calcium stearate, and sodium carboxymethyl cellulose. 6 . The resin combination according to claim 1 , wherein the photoinitiator is at least one of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) and 1-hydroxycyclohexyl phenyl ketone (Irgacure-184). 7 . The resin combination according to claim 1 , wherein the ultraviolet absorber is one or more of benzotriazole, substituted acrylonitrile, triazine, salicylate, and benzophenone ultraviolet absorbers. 8 . The resin combination according to claim 1 , wherein the defoaming agent is one or more of an alcohol defoaming agent, a silicone resin defoaming agent, and a polyether-modified silicone oil defoaming agent. 9. The resin combination according to claim 1 is characterized in that the ground fiber is an inorganic fiber, including at least one of ground glass fiber, ground asbestos fiber, ground carbon fiber, ground alumina fiber, ground zirconium oxide fiber, ground silicon carbide fiber, ground aluminum silicate fiber, ground silicon nitride fiber, ground graphene fiber, and ground basalt fiber. 10. The resin combination according to claim 1, wherein the ground fiber is subjected to degreasing treatment and coupling agent treatment. 11. The resin combination according to claim 10, characterized in that the degreasing treatment of the ground fiber is performed by placing the ground fiber in a high-temperature furnace protected by inert gas and performing degreasing treatment at a high temperature of 400-1400°C for 0.5-6h. 12. The resin combination according to claim 10, characterized in that the coupling agent treatment of the ground fiber comprises mixing the ground fiber, solvent and coupling agent, refluxing, and drying to obtain the surface-modified ground fiber. 13 . The resin combination according to claim 12 , wherein the coupling agent is at least one of a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent. 14. The resin combination according to claim 12 or 13, characterized in that the mass ratio of the ground fiber, the solvent and the coupling agent is (80-110): (80-110): (0.2-3). 15. The resin combination according to claim 12 or 13, characterized in that the reflux temperature is 70-100°C; and the reflux time is 4-6h. 16. A method for preparing the resin composition according to any one of claims 1 to 15, comprising the following steps: Step (1), grinding fiber modification treatment refluxing the ground fiber, the solvent, and the coupling agent to obtain a coupled ground fiber; Step (2), preparing a resin solution Mixing acrylate resin oligomer, active diluent monomer, structure stabilizer, photoinitiator, ultraviolet absorber and defoamer, stirring evenly to obtain a resin solution; Step (3), preparing a resin composition The ground fiber obtained in step (1) and the resin solution obtained in step (2) are mixed and rotated in an internal mixer to obtain a resin composition. 17. The method for preparing a resin composition according to claim 16, characterized in that the rotation speed of the rotary process in the internal mixer is set to 2000-3000 r/min, and the rotation time is 4-6 h. 18 . The method for preparing a resin composition according to claim 16 , wherein the viscosity of the resin composition is 100-600 mPa·s. 19. Use of the UV-curable resin composition according to any one of claims 1 to 15 in three-dimensional printing. 20. Use of a ground fiber in three-dimensional printing, wherein the ground fiber is the ground fiber in the ultraviolet light-curable resin composition according to any one of claims 1 to 15.