阅读说明：本技术 一种液态金属/聚合物3d打印油墨及其制备方法 (Liquid metal/polymer 3D printing ink and preparation method thereof ) 是由 王振华 高小宇 范文如 张彪 陈祥 刘福康 于 2020-12-22 设计创作，主要内容包括：本发明开发了一种液态金属/聚合物3D打印油墨的方法,包括以下步骤：以表面引发剂改性后的液态金属液滴、铜催化剂和丙烯酸酯单体混合,进行冰浴超声引发聚合；在达到设定的转化率之后,终止反应,得到液态金属/聚合物复合材料；按照比例加入光引发剂和交联剂得混合液,并震荡混匀,得到3D打印油墨。该方法具有材料荧光可调、力学性能可调、可3D打印的特点,而且避免了传统液态金属/聚合物材料制备方法中存在的液态金属沉降过快、只能制备薄膜材料、材料力学性能弱、材料功能单一等缺点,因此具有很高的应用价值。(The invention discloses a method for 3D printing ink of liquid metal/polymer, which comprises the following steps: mixing liquid metal droplets modified by a surface initiator, a copper catalyst and an acrylate monomer, and carrying out ice-bath ultrasonic initiation polymerization; after the set conversion rate is reached, terminating the reaction to obtain a liquid metal/polymer composite material; and adding a photoinitiator and a cross-linking agent according to a ratio to obtain a mixed solution, and uniformly mixing the mixed solution by shaking to obtain the 3D printing ink. The method has the characteristics of adjustable fluorescence and mechanical property of the material and capability of 3D printing, and avoids the defects of too fast liquid metal sedimentation, only preparation of thin film materials, weak mechanical property of the material, single function of the material and the like in the traditional preparation method of the liquid metal/polymer material, so that the method has high application value.)

1. The liquid metal/polymer 3D printing ink is characterized by comprising the following raw materials in percentage by mass:

the balance of the liquid metal/polymer composite;

0.5 to 10 percent of photoinitiator;

1-10% of a cross-linking agent;

the liquid metal/polymer composite material is obtained by polymerizing liquid metal droplets modified by a surface initiator, a copper catalyst and an acrylate monomer; wherein the volume fraction of the liquid metal droplets is 1-50% of the total volume of the solution; the adding molar ratio of the acrylate monomer, the surface modification initiator and the copper catalyst is 1: 0.0021: 2.4X 10^-5。

2. A liquid metal/polymer 3D printing ink according to claim 1, characterized in that: the liquid metal liquid drop after surface modification is a nano gallium-indium alloy liquid drop and a nano gallium-indium-tin alloy liquid drop, the surface of the liquid metal liquid drop contains 2-bromine-N- (2- ((((((8-hydroxyquinoline-2-yl) methyl) amino) ethyl) -2-methylpropionamide.

3. A liquid metal/polymer 3D printing ink according to claim 2, characterized in that: the nano gallium-indium alloy liquid drop contains 75 wt% of gallium and 25 wt% of indium in percentage by mass;

the nano gallium indium tin alloy liquid drop contains 68 wt% of gallium, 22 wt% of indium and 10 wt% of tin in percentage by mass.

4. A liquid metal/polymer 3D printing ink according to claim 1, characterized in that: the liquid metal droplet has a particle size of 100nm-1 μm, preferably 300-500 nm.

5. A liquid metal/polymer 3D printing ink according to claim 1, characterized in that: the copper catalyst is copper bromide/pentamethyldiethylenetriamine, copper bromide/tris (2-dimethylaminoethyl) amine, copper bromide/tris (2-picolyl) amine or copper bromide/bipyridyl.

6. A liquid metal/polymer 3D printing ink according to claim 1, characterized in that: the acrylate monomer is one or more of (methyl) acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, ethyl acrylate, methyl acrylate, butyl acrylate, tert-butyl acrylate, hydroxyethyl acrylate, polyethylene glycol dimethacrylate, N-diethylamino ethyl methacrylate, N-dimethylamino ethyl methacrylate, trifluoroethyl acrylate and trifluoroethyl methacrylate.

7. A liquid metal/polymer 3D printing ink according to claim 1, characterized in that: and the step of introducing nitrogen to remove oxygen is also included after the mixing.

8. A liquid metal/polymer 3D printing ink according to claim 1, characterized in that: the liquid metal droplet volume fraction is the liquid metal droplet volume/total solution volume.

9. A liquid metal/polymer 3D printing ink according to claim 1, characterized in that: the addition amount of the photoinitiator accounts for 1 percent of the mass of the mixed solution; the addition amount of the cross-linking agent accounts for 3% of the mass of the mixed solution.

10. A preparation method of liquid metal/polymer 3D printing ink is characterized by comprising the following steps:

mixing liquid metal droplets modified by a surface initiator, a copper catalyst and an acrylate monomer, and carrying out ice-bath ultrasonic initiation polymerization;

after the set conversion rate is reached, terminating the reaction to obtain a liquid metal/polymer composite material;

and adding a photoinitiator and a cross-linking agent according to a ratio to obtain a mixed solution, and uniformly mixing the mixed solution by shaking to obtain the 3D printing ink.

Technical Field

The invention belongs to the technical field of materials, relates to preparation of a liquid metal/polymer composite material, and particularly relates to liquid metal/polymer 3D printing ink and a preparation method thereof.

Background

The flexible electronic material is a material with both flexibility and electronic performance, and has wide application prospect in the fields of wearable technology, flexible robots, transducers and the like. Both dielectric elastomer materials and flexible conductor materials belong to flexible electronic systems. The traditional method researches the materials by introducing rigid particles into an elastomer matrix so as to increase the electrical properties of the materials, but because the inherent rigidity of the inorganic filler is not matched with the flexibility of the elastomer matrix, the internal stress of the materials is concentrated, the system rigidity is increased, the ductility is reduced, and meanwhile, the durability of the materials in mechanical response is limited. For stretchable conductive materials, research reports on materials with high conductivity and high mechanical flexibility exist, and similarly, high dielectric constant, low elastic modulus and low dielectric loss of dielectric elastomer materials are difficult to be simultaneously considered, and most elastomer composite materials only have single functions of single conductivity or heat conductivity and the like, so that the application of the materials is limited.

At present, liquid metal has excellent properties such as low melting point, high electrical conductivity, high thermal conductivity, low viscosity, negligible low toxicity and the like, and can spontaneously form a protective oxide film when exposed to air, the layer of oxide film not only enables the liquid metal to have formability, but also enables the liquid metal to have good wettability to non-metallic materials, and the liquid metal/polymer composite material can meet the requirements of electrical conductivity and flexibility when being used as a filler in a polymer matrix composite material, so the liquid metal/polymer composite material receives great attention. The liquid metal is combined with the polymer in a mode of a liquid metal layer wrapped by the elastic polymer, the liquid metal fills the conductive path in the polymer and liquid metal drops are dispersed in the polymer matrix. Wherein both the liquid metal layer and the internal passages are susceptible to leakage or pill formation of the liquid metal. The liquid metal drop dispersion mode mainly comprises mechanical stirring and ultrasonic dispersion, wherein the mechanical forced dispersion of the liquid metal can cause the liquid metal to form irregularly distributed micron-sized inclusions in a matrix, and the ultrasonic dispersion can control the formation of uniform liquid metal drop inclusions by regulating and controlling ultrasonic power and time. To optimize the dispersion of liquid metal droplets within the aggregate, the investigator make internal disorder or usurp attempted to ultrasonically disperse liquid metal particles and stabilized the particle morphology with surfactants, which currently could be controlled in the tens of nanometers to over one micron range.

However, at present, ligand molecules are added to form a self-assembled film on the surface of a liquid metal droplet in the liquid metal ultrasonic dispersion process, and although the method can play a role in stabilizing the liquid metal droplet, the liquid metal is rapidly settled and has poor mechanical properties in the polymer matrix solidification process due to the weak binding force between the ligand and the liquid metal, so that the application of the liquid metal/polymer composite material is concentrated on the electric and heat conducting film material.

Disclosure of Invention

The invention provides liquid metal/polymer 3D printing ink and a preparation method thereof, and provides liquid metal/polymer composite ink prepared by an ultrasonic chemical technology surface-initiated atom transfer radical polymerization technology to realize 3D printing forming of a liquid metal/polymer composite material, so that the material has good mechanical properties and has the characteristics of electrical conductivity, thermal conductivity, dielectricity, photo-thermal response and the like.

The technical scheme of the invention is as follows:

a liquid metal/polymer 3D printing ink comprises the following raw materials in percentage by mass:

the balance of the liquid metal/polymer composite;

0.5 to 10 percent of photoinitiator;

1-10% of a cross-linking agent;

the liquid metal/polymer composite material is obtained by polymerizing liquid metal droplets modified by a surface initiator, a copper catalyst and an acrylate monomer; wherein the volume fraction of the liquid metal droplets is 1-50% of the total volume of the solution; the adding molar ratio of the acrylate monomer, the surface modification initiator and the copper catalyst is 1: 0.0021: 2.4X 10^-5。

As a further improvement of the invention, the liquid metal liquid drop after surface modification is a nano gallium-indium alloy liquid drop and a nano gallium-indium-tin alloy liquid drop, the surface of which contains 2-bromine-N- (2- ((((((8-hydroxyquinoline-2-yl) methyl) amino) ethyl) -2-methylpropanamide.

As a further improvement of the invention, the nano gallium-indium alloy liquid drop contains 75 wt% of gallium and 25 wt% of indium in percentage by mass;

the nano gallium indium tin alloy liquid drop contains 68 wt% of gallium, 22 wt% of indium and 10 wt% of tin in percentage by mass.

As a further development of the invention, the liquid metal droplet has a particle size of from 100nm to 1 μm, preferably from 300 to 500 nm.

As a further development of the invention, the copper catalyst is copper bromide/pentamethyldiethylenetriamine, copper bromide/tris (2-dimethylaminoethyl) amine, copper bromide/tris (2-picolyl) amine or copper bromide/bipyridine.

As a further improvement of the invention, the acrylate monomer is one or more of (meth) acrylate such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, ethyl acrylate, methyl acrylate, butyl acrylate, t-butyl acrylate, hydroxyethyl acrylate, polyethylene glycol dimethacrylate, N-diethylamino ethyl methacrylate, N-dimethylamino ethyl methacrylate, trifluoroethyl acrylate and trifluoroethyl methacrylate.

As a further improvement of the invention, the mixing step further comprises a nitrogen introducing and oxygen removing step.

As a further refinement of the present invention, the liquid metal droplet volume fraction is liquid metal droplet volume/total solution volume.

As a further improvement of the invention, the addition amount of the photoinitiator accounts for 1 percent of the mass of the mixed solution; the addition amount of the cross-linking agent accounts for 3% of the mass of the mixed solution.

A preparation method of liquid metal/polymer 3D printing ink comprises the following steps:

mixing liquid metal droplets modified by a surface initiator, a copper catalyst and an acrylate monomer, and carrying out ice-bath ultrasonic initiation polymerization;

after the set conversion rate is reached, terminating the reaction to obtain a liquid metal/polymer composite material;

and adding a photoinitiator and a cross-linking agent according to a ratio to obtain a mixed solution, and uniformly mixing the mixed solution by shaking to obtain the 3D printing ink.

Compared with the prior art, the invention has the following technical effects:

the invention mainly uses the ultrasonic chemical technology surface initiation atom transfer free radical polymerization technology, combines ultrasonic oscillation to realize the uniform dispersion of liquid metal liquid drops and an initiator in a system, regulates and controls the viscosity of the ink and the mechanical property and the photo-thermal electrical property of a cured material by controlling parameters such as the ratio between a monomer and liquid metal, the monomer conversion rate, the monomer type, the initiator content and the like, realizes the in-situ generation of the liquid metal/polymer composite ink by a one-step polymerization method, and obtains a 3D printing composite material with excellent performance. The method has the characteristics of adjustable fluorescence and mechanical property of the material and 3D printing, and avoids the defects of over-quick liquid metal sedimentation, only preparation of a thin film material, weak mechanical property of the material, single function of the material and the like in the traditional preparation method of the liquid metal/polymer material, so that the method has high application value.

When an external light field irradiates the metal nanoparticles, free electrons in the metal nanoparticles interact with an incident light field to initiate cluster oscillation of the free electrons, and if the frequency of the incident light field is the same as the oscillation frequency of the free electrons of the metal nanoparticles, surface plasmons (SPPs) can be effectively excited. When SPP is transmitted in metal, the existence of the imaginary part of the dielectric constant of the metal can generate strong loss to the optical field, and the energy in the optical field is converted into heat through the joule heat effect.

Drawings

FIG. 1 is a flow chart showing the specific implementation of the present invention.

FIG. 2 is a graph of the storage modulus (solid line) and dissipation factor tan δ (dashed line) for polymer/liquid metal composites of different liquid metal volume fractions and degrees of crosslinking.

Fig. 3 is an image under a 3D printed sample optical microscope, (a) an image of a sample sphere at five times magnification, (b) an image of a sample sphere at ten times magnification, and (c) an image of a sample sphere at 245nm uv lamp illumination.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced otherwise than as specifically described herein, and thus the scope of the present invention is not limited by the specific embodiments disclosed below.

The invention discloses a method for preparing liquid metal/polymer 3D printing ink in situ by ultrasound, which comprises the following steps:

introducing nitrogen into liquid metal droplets (300-500nm), a copper catalyst and acrylate modified by a surface initiator for 30 minutes, and then placing the liquid metal droplets into ultrasonic equipment for oscillation;

starting ultrasonic equipment, and stopping reaction after a set conversion rate is reached to obtain ink for 3D photocuring molding;

before 3D printing, adding a photoinitiator and a cross-linking agent into printing ink according to a certain proportion, uniformly mixing by oscillation, and then carrying out ultraviolet curing molding in a printer.

The liquid metal liquid drop after surface modification is a nano gallium indium alloy liquid drop (EGaIn,75 wt% gallium and 25 wt% indium) and a nano gallium indium tin alloy liquid drop (Galinstan, 68 wt% gallium, 22 wt% indium and 10 wt% tin) of which the surface contains 2-bromine-N- (2- (((((8-hydroxyquinoline-2-yl) methyl) amino) ethyl) -2-methylpropionamide.

Example 1

Liquid metal (6.25g,1mL), tert-butyl acrylate (10mL), copper bromide (0.27mg), 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (53mg) were mixed uniformly under the ultrasonic action of a cell disrupter (75W, 20min, ice bath), after aeration with nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 1 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 3 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 2

Uniformly mixing liquid metal (1.57g,0.25mL), butyl acrylate (5mL), copper bromide (0.1mg) and 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (2.66mg) under the ultrasonic action of a cell disrupter (75W, 20min, ice bath), introducing nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 5% by mass of photoinitiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 1% by mass of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 3

Uniformly mixing liquid metal (1.57g,0.25mL), methyl acrylate (5mL), copper bromide (0.1mg) and 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (2.66mg) under the ultrasonic action of a cell disrupter (75W, 20min, ice bath), introducing nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding a photoinitiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) accounting for 10% by mass and a cross-linking agent (ethylene glycol dimethacrylate) accounting for 3% by mass into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 4

Liquid metal (1.57g,0.25mL), allyl methacrylate (5mL), copper bromide (0.1mg), 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (2.84mg) were mixed uniformly under the ultrasonic action of a cell disrupter (75W, 20min, ice bath), after aeration with nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 5% by mass of an initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 5% by mass of a cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 5

Uniformly mixing liquid metal (1.57g,0.25mL), ethyl acrylate (5mL), copper bromide (0.1mg) and 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (3.58mg) under the ultrasonic action of a cell disrupter (75W, 20min, ice bath), introducing nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 8 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 9 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 6

Uniformly mixing liquid metal (1.57g,0.25mL), hydroxyethyl acrylate (5mL), copper bromide (0.1mg) and 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (3.63mg) under the ultrasonic action of a cell disrupter (75W, 20min, ice bath), introducing nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 10% by mass of an initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 10% by mass of a cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing the mixture by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 7

Uniformly mixing liquid metal (1.57g,0.25mL), butyl methacrylate (5mL), copper bromide (0.1mg) and 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (2.41mg) under the ultrasonic action of a cell disrupter (75W, 20min, ice bath), introducing nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 3 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 5 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 8

Liquid metal (1.57g,0.25mL), ethyl acrylate (1mL), methyl methacrylate (4mL), copper bromide (0.1mg), 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (3.60mg) were mixed uniformly under the ultrasonic action of a cell disruptor (75W, 20min, ice bath), after aeration with nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 5% by mass of an initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 8% by mass of a cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 9

Liquid metal (1.57g,0.25mL), allyl methacrylate (1mL), methyl methacrylate (4mL), copper bromide (0.1mg), 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (3.43mg) were mixed uniformly under the ultrasonic action of a cell disruptor (75W, 20min, ice bath), after deoxygenation by introducing nitrogen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 1.5 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 2.5 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 10

Liquid metal (1.57g,0.25mL), butyl acrylate (1mL), methyl methacrylate (4mL), copper bromide (0.1mg), 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (3.60mg) were mixed uniformly under the ultrasonic action of a cell disruptor (75W, 20min, ice bath), after aeration with nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 1.5 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 4 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 11

Liquid metal (1.88g,0.30mL), butyl acrylate (2mL), methyl methacrylate (4mL), copper bromide (0.14mg), 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (3.93mg) were mixed uniformly under the ultrasonic action of a cell disruptor (75W, 20min, ice bath), after aeration with nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 1 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 3 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 12

Liquid metal (1.88g,0.30mL), ethyl acrylate (2mL), methyl methacrylate (4mL), copper bromide (0.15mg), 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (4.29mg) were mixed uniformly under the ultrasonic action of a cell disruptor (75W, 20min, ice bath), after aeration with nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 1 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 10 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 13

Liquid metal (9.38g, 1.50mL) was mixed with hydroxyethyl acrylate (2mL), methyl methacrylate (4mL), copper bromide (0.16mg), 2-bromo-N- (2- (((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (4.31mg) uniformly under the ultrasonic action of a cell disruptor (75W, 20min, ice bath), after aeration with nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 1 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 3 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

Example 14

Liquid metal (18.75g,3.00mL), allyl methacrylate (2mL), methyl methacrylate (4mL), copper bromide (0.15mg), 2-bromo-N- (2- ((((((8-hydroxyquinolin-2-yl) methyl) amino) ethyl) -2-methylpropanamide (4.00mg) were mixed uniformly under the ultrasonic action of a cell disrupter (75W, 20min, ice bath), after aeration with nitrogen to remove oxygen for 30min, placing in an ultrasonic cleaner, starting ultrasonic to initiate polymerization, stopping reaction after nuclear magnetism measures conversion rate, adding 1 mass percent of initiator (phenyl bis (2,4, 6-trimethylbenzoyl) phosphorus oxide) and 5 mass percent of cross-linking agent (ethylene glycol dimethacrylate) into the mixed solution, uniformly mixing by shaking to obtain printing ink, and adding the printing ink into a 3D printer for photocuring printing.

In order to compare the mechanical properties of composite materials with different liquid metal volume fractions and different crosslinking degrees, the storage modulus and loss factor change of a test sample is tested under the condition that the measurement frequency is 1Hz by a dynamic mechanical test (DMA) under the nitrogen atmosphere and at the temperature rise rate of 3 ℃/min (-40 ℃ -150 ℃).

FIG. 2 storage modulus (solid line) and dissipation factor tan δ (dashed line) for polymer/liquid metal composites of different liquid metal volume fractions and degrees of crosslinking (note: tBA as monomer, 5 and 10 as different volume fractions of liquid metal, 1 and 3 as different crosslink densities)

As can be seen from fig. 2, the glass transition temperature of the material is lower at higher liquid metal contents, because the coordination between the liquid metal and the surface ligands is weaker relative to the chemical bonds between the segments, and when the temperature is increased and the stress is increased, the liquid metal and the polymer chain interface is separated, which is equivalent to reducing the crosslink density, and therefore the transition from the glassy state to the viscous state is easier. Moreover, all samples had a storage modulus that dropped to zero and the samples would yield at high temperatures. This may be due to stress relaxation caused by separation of the liquid metal and polymer interface at high temperatures.

Fig. 33D prints an image under an optical microscope of the sample. (a) The sample sphere magnifies the image by a factor of five. (b) The image of the sample sphere is magnified ten times. (c) Image of sample sphere magnified under 245nm UV lamp illumination.

As can be seen from fig. 3, the liquid metal/polymer composite ink can print a three-dimensional complex solid structure. Fig. 3(b) shows that the different cured layers are tightly bonded and there is no significant delamination. As shown in fig. 3(c), the sample can exhibit a fluorescent green color under uv lamp illumination, which adds more interesting designs for the application of the material.

All articles and references disclosed above, including patent applications and publications, are hereby incorporated by reference for all purposes. The term "consisting essentially of …" describing a combination shall include the identified element, ingredient, component or step as well as other elements, ingredients, components or steps that do not materially affect the basic novel characteristics of the combination. The use of the terms "comprising" or "including" to describe combinations of elements, components, or steps herein also contemplates embodiments that consist essentially of such elements, components, or steps. By using the term "may" herein, it is intended to indicate that any of the described attributes that "may" include are optional.

A plurality of elements, components, parts or steps can be provided by a single integrated element, component, part or step. Alternatively, a single integrated element, component, part or step may be divided into separate plural elements, components, parts or steps. The disclosure of "a" or "an" to describe an element, ingredient, component or step is not intended to foreclose other elements, ingredients, components or steps.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided would be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are hereby incorporated by reference for all purposes. The omission in the foregoing claims of any aspect of subject matter that is disclosed herein is not intended to forego such subject matter, nor should the applicant consider that such subject matter is not considered part of the disclosed subject matter.