A bio-based recyclable photocurable 3D printing deep eutectic solvent, and a preparation method and application thereof

Abstract

The application discloses a bio-based recyclable photocurable 3D printing eutectic solvent and a preparation method and application thereof. First, a bio-based hydrogen bond donor and an unsaturated monomer hydrogen bond acceptor are mixed, heated to 50-100 DEG C and reacted for 0.5-4 h to obtain a eutectic solvent; second, the eutectic solvent, a polymerization inhibitor and a photoinitiator are uniformly dispersed, wherein the amount of the polymerization inhibitor is 0.1%-5% of the total weight of raw materials, and the amount of the photoinitiator is 0.1%-5% of the total weight of the obtained photocurable eutectic solvent, to obtain a photocurable 3D printing eutectic solvent. The bio-based recyclable photocurable 3D printing eutectic solvent synthesized by the application has the advantages of simple synthesis method, high bio-based content, moderate viscosity, fast photocuring rate, degradable recycling and recyclable photocurable 3D printing.

Description

Technical Field

[0001] This invention belongs to the field of synthetic polymer materials, specifically relating to a bio-based recyclable photopolymerizable eutectic solvent for 3D printing, its preparation method, and its application. Background Technology

[0002] Photopolymer 3D printing technology has become a research hotspot in additive manufacturing, with wide applications in aerospace, medical, and intelligent manufacturing. While significant progress has been made in both hardware and software, the availability of 3D printing materials remains limited, severely restricting the technology's development. Furthermore, with the growing emphasis on sustainable 3D printing, the design and synthesis of sustainable photopolymer 3D printing materials has attracted widespread attention. Biomass resources are abundant, renewable, biocompatible, and easily degradable, and more importantly, they reduce the use of petrochemical resources at the source. Using biomass as a raw material to synthesize photopolymer 3D printing materials perfectly aligns with the concept of sustainable photopolymer 3D printing. However, reported bio-based photopolymer 3D materials are difficult to recycle, and discarded printed parts place significant pressure on the environment. Therefore, there is an urgent need to design and develop bio-based recyclable photopolymer 3D printing materials to address the environmental pollution caused by discarded printing materials.

[0003] Deep eutectic solvents are a novel type of green solvent with extremely simple synthesis and raw materials derived from biomass resources. They consist of two parts: hydrogen bond donors and hydrogen bond acceptors, exhibiting strong tunability. When either the hydrogen bond donor or acceptor contains C=C, the deep eutectic solvent can polymerize under photoinitiator conditions to obtain a novel photocurable material. This invention utilizes biomass acids and biomass alcohols as hydrogen bond donors and unsaturated monomers containing C=C double bonds as hydrogen bond acceptors to synthesize a novel biomass deep eutectic solvent, which is then applied to photocurable 3D printing. Simultaneously, the 3D printing material of this invention can gradually degrade in the hydrogen bond acceptors, and the degradation solution can be reused for photocurable 3D printing, thus achieving cyclic photocurable 3D printing. In summary, this invention develops a bio-based recyclable photocurable 3D printing deep eutectic solvent, which is expected to solve the problems of waste and pollution from discarded 3D printing materials and is highly beneficial for sustainable 3D printing. Summary of the Invention

[0004] Technical problem solved: This invention overcomes the problem that traditional photocurable materials are difficult to recycle and reuse, and provides a bio-based recyclable photocurable eutectic solvent for 3D printing, its preparation method and application.

[0005] Technical solution: A method for preparing a bio-based recyclable photocurable eutectic solvent for 3D printing, comprising the following steps: First, a bio-based hydrogen bond donor and an unsaturated monomer-type hydrogen bond acceptor are mixed in a molar ratio of 1:(1-5) and heated to 50~100 ℃ for 0.5~4 h to obtain a eutectic solvent; Second, the eutectic solvent, a polymerization inhibitor, and a photoinitiator are dispersed evenly, wherein the amount of polymerization inhibitor is 0.1%~5% of the total weight of the raw materials, and the amount of photoinitiator is 0.1%~5% of the total weight of the obtained photocurable eutectic solvent to obtain a photocurable 3D printing eutectic solvent.

[0006] The aforementioned bio-based hydrogen bond donors are at least one of citric acid, malic acid, lactic acid, fumaric acid, oleic acid, tartaric acid, itaconic acid, crotonic acid, vanillic acid, ethylene glycol, 1,3-propanediol, glycerol, 1,6-hexanediol, oleyl alcohol, eugenol, cashew nut, guaiacol, and catechin.

[0007] The aforementioned unsaturated monomeric hydrogen bond acceptors are at least one of N,N-dimethylacrylamide, 4-acryloylmorpholine, isoborneol acrylate, methyl acrylate, tetrahydrofuran acrylate, hydroxyethyl acrylate, isoborneol methacrylate, acrylic acid, methacrylic acid, acrylamide, and methacrylamide.

[0008] The molar ratio of the aforementioned bio-based hydrogen bond donor to the unsaturated monomeric hydrogen bond acceptor is 1:2.

[0009] The above-mentioned polymerization inhibitor is at least one of hydroquinone, p-benzoquinone, p-methoxyphenol, and 2,6-di-tert-butyl-p-methylphenol, and the amount used is 0.5% of the total weight of the raw materials.

[0010] The photoinitiator mentioned above is at least one of 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyldiphenoxyphosphine, 2-hydroxy-2-methyl-1-phenyl-1-propanone, benzoin dimethyl ether, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2,4,6-trimethylbenzoyl phosphate ethyl ester, 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, 2-isopropylthioxanthraquinone, and 4-chlorobenzophenone. The amount of photoinitiator used is 0.15% of the total weight of the obtained photocurable eutectic solvent.

[0011] The bio-based eutectic solvent prepared by the above method.

[0012] The application of the above-mentioned bio-based eutectic solvents in the preparation of photopolymerizable 3D printing materials.

[0013] The specific method of application is to dissolve the printed model into an unsaturated monomeric hydrogen bond acceptor, with a mass ratio of the printed model to the unsaturated monomeric hydrogen bond acceptor of 1:4~8, to obtain a degradation solution. Then, according to the above, bio-based hydrogen bond donors, photoinitiators, and polymerization inhibitors are added to obtain a low eutectic solvent that can be photocured for 3D printing again. A new model is then photocured again to 3D print, thereby realizing photocuring cyclic printing.

[0014] Beneficial effects: (1) The bio-based recyclable photocurable eutectic solvent for 3D printing synthesized in this invention has a simple synthesis method, high bio-based content, moderate viscosity, fast photocuring rate, and is degradable, recyclable, and recyclable for photocurable 3D printing. (2) This invention overcomes the problem of traditional photocurable 3D printing materials being difficult to recycle and reuse, avoids waste and pollution of 3D printing materials, and improves resource utilization efficiency. Attached Figure Description

[0015] Figure 1 Infrared spectrum of bio-based recyclable photopolymerizable 3D printing eutectic solvent Detailed Implementation

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the specific content of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0017] Example 1

[0018] (1) Add malic acid and N,N-dimethylacrylamide to the reactor. The molar ratio of malic acid to N,N-dimethylacrylamide is 1:1. After stirring evenly, heat to 60 °C and react for 0.5 h to obtain malic acid-based eutectic solvent.

[0019] (2) Hydroquinone and 2,4,6-trimethylbenzoyldiphenyloxyphosphine were added to a malic acid-based eutectic solvent, wherein the amount of hydroquinone as the polymerization inhibitor was 0.5% of the total weight of the raw materials and the amount of 2,4,6-trimethylbenzoyldiphenyloxyphosphine as the photoinitiator was 0.5% of the total weight of the raw materials. The mixture was stirred evenly and the air bubbles were removed to obtain a malic acid-based photocurable eutectic solvent for 3D printing.

[0020] Example 2

[0021] (1) Add citric acid and N,N-dimethylacrylamide to the reactor. The molar ratio of citric acid to N,N-dimethylacrylamide is 1:1. After stirring evenly, heat to 60 °C and react for 0.5 h to obtain a citric acid-based eutectic solvent.

[0022] (2) Hydroquinone and 2,4,6-trimethylbenzoyl diphenyloxyphosphine were added to a citric acid-based eutectic solvent, wherein the amount of hydroquinone as the polymerization inhibitor was 0.5% of the total weight of the raw materials and the amount of 2,4,6-trimethylbenzoyl diphenyloxyphosphine as the photoinitiator was 0.5% of the total weight of the raw materials. The mixture was stirred evenly and the air bubbles were removed to obtain a citric acid-based photocurable eutectic solvent for 3D printing.

[0023] Example 3

[0024] (1) Add ethylene glycol and N,N-dimethylacrylamide to the reactor. The molar ratio of ethylene glycol to N,N-dimethylacrylamide is 1:1. After stirring evenly, heat to 60 °C and react for 0.5 h to obtain ethylene glycol-based eutectic solvent.

[0025] (2) Hydroquinone and 2,4,6-trimethylbenzoyldiphenyloxyphosphine were added to a glycol-based eutectic solvent, wherein the amount of hydroquinone as the polymerization inhibitor was 0.5% of the total weight of the raw materials and the amount of 2,4,6-trimethylbenzoyldiphenyloxyphosphine as the photoinitiator was 0.5% of the total weight of the raw materials. The mixture was stirred evenly and the air bubbles were removed to obtain a glycol-based photocurable eutectic solvent for 3D printing.

[0026] Example 4

[0027] (1) Add glycerol and N,N-dimethylacrylamide to the reactor. The molar ratio of glycerol to N,N-dimethylacrylamide is 1:1. After stirring evenly, heat to 60 °C and react for 0.5 h to obtain glycerol-based eutectic solvent.

[0028] (2) Hydroquinone and 2,4,6-trimethylbenzoyldiphenyloxyphosphine were added to a glycerol-based eutectic solvent, wherein the amount of hydroquinone as the polymerization inhibitor was 0.5% of the total weight of the raw materials and the amount of 2,4,6-trimethylbenzoyldiphenyloxyphosphine as the photoinitiator was 0.5% of the total weight of the raw materials. The mixture was stirred evenly and the air bubbles were removed to obtain a glycerol-based photocurable eutectic solvent for 3D printing.

[0029] Examples 5-8

[0030] Weigh 50 g of the resin from Examples 1 to 4 respectively, add 0.05 g of light blocker 2,5-bis-(5-tert-butyl-2-benzoxazolyl)thiophene, stir evenly, and degas. Pour the mixture into the resin tank of a Form3 SLA photopolymer 3D printer (Formlabs, USA) for photopolymerization printing.

[0031] Examples 9-12

[0032] The initial printed models from Examples 5-8 were pulverized and added to an unsaturated monomeric hydrogen bond acceptor solution at a mass ratio of 1:6. The mixture was stirred until homogeneous and then heated to 90°C for 8 hours to degrade, yielding a degradation solution. A quantitative amount of bio-based hydrogen bond donor was added according to the molar amount of unsaturated monomeric hydrogen bond donor in the degradation solution. After stirring until homogeneous, the mixture was heated to 80°C for 2 hours to obtain a regenerated bio-based eutectic solvent, which was then photocured to 3D print a new model.

[0033] Examples 13-16

[0034] The viscosity of the eutectic solvent for bio-based recyclable photopolymerizable 3D printing in Examples 1-4 and 9-12 was tested, as well as the mechanical properties of the 3D printing material. Tensile properties: The mechanical properties of the 3D printed models were determined according to ASTM D638-2008 using a SANS7 CMT-4304 universal testing machine (Shenzhen Xin Sansi Instrument Co., Ltd.), with a gauge length of 50 mm and a tensile rate of 5.0 mm / min. The model dimensions were 80 × 10 × 1 mm. 3 Viscosity: The resin viscosity was measured using a DVS+ rotational viscometer (Boller Corporation, USA).

[0035]

[0036] The above examples are merely illustrative of the technical concept and features of the present invention, intended to enable those skilled in the art to understand the content of the invention and implement it accordingly, and should not be construed as limiting the scope of protection of the present invention. All equivalent transformations or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a bio-based, recyclable photopolymerizable 3D printing eutectic solvent, characterized in that, The steps are as follows: First, a bio-based hydrogen bond donor and an unsaturated monomer-type hydrogen bond acceptor are mixed in a molar ratio of 1:(1-5) and heated to 50-100 °C for 0.5-4 h to obtain a eutectic solvent; second, the eutectic solvent, polymerization inhibitor, and photoinitiator are dispersed evenly, wherein the amount of polymerization inhibitor is 0.1%-5% of the total weight of the raw materials, and the amount of photoinitiator is 0.1%-5% of the total weight of the obtained photocurable eutectic solvent to obtain a photocurable 3D printing eutectic solvent; the bio-based hydrogen bond donor is at least one of citric acid, malic acid, ethylene glycol, or glycerol, and the unsaturated monomer-type hydrogen bond acceptor is N,N-dimethylacrylamide.

2. The method for preparing the bio-based recyclable photopolymerizable eutectic solvent for 3D printing according to claim 1, characterized in that, The molar ratio of the bio-based hydrogen bond donor to the unsaturated monomeric hydrogen bond acceptor is 1:

2.

3. The method for preparing the bio-based recyclable photopolymerizable 3D printing eutectic solvent according to claim 1, characterized in that, The polymerization inhibitor is at least one of hydroquinone, p-benzoquinone, p-methoxyphenol, and 2,6-di-tert-butyl-p-methylphenol, and is used in an amount of 0.5% of the total weight of the raw materials.

4. The method for preparing the bio-based recyclable photopolymerizable eutectic solvent for 3D printing according to claim 1, characterized in that, The photoinitiator is at least one selected from 1-hydroxycyclohexylphenyl ketone, 2,4,6-trimethylbenzoyldiphenoxyphosphine, 2-hydroxy-2-methyl-1-phenyl-1-propanone, benzoin dimethyl ether, 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone, 2,4,6-trimethylbenzoyl phosphate ethyl ester, 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, 2-isopropylthioxanthraquinone, and 4-chlorobenzophenone. The amount of photoinitiator used is 0.15% of the total weight of the obtained photocurable eutectic solvent.

5. A bio-based eutectic solvent prepared by any of the preparation methods described in claims 1-4.

6. The application of the bio-based eutectic solvent of claim 5 in the preparation of photopolymerizable 3D printing materials.

7. The application according to claim 6, characterized in that, The printing model is dissolved in an unsaturated monomeric hydrogen bond acceptor at a mass ratio of 1:4 to 8 to obtain a degradation solution. A bio-based hydrogen bond donor, a photoinitiator, and a polymerization inhibitor are added according to the preparation method described in claim 1 to obtain a eutectic solvent that can be photocured for 3D printing again. A new model is then photocured again to 3D print, thereby achieving photocuring cyclic printing.

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