阅读说明：本技术 基于丁羟胶的固体推进剂3d打印油墨及其制备方法 (Solid propellant 3D printing ink based on butylated hydroxytoluene and preparation method thereof ) 是由 鲁在君 苟拓展 邢宏宇 邹斌 于 2020-02-26 设计创作，主要内容包括：本发明涉及基于丁羟胶的固体推进剂3D打印油墨及其制备方法,固体推进剂3D打印油墨可紫外光固化,包括：丁羟胶基光敏树脂10％-60％、分散剂1％-5％、氧化剂25％-70％、金属燃料10％-20％；丁羟胶基光敏树脂包括原料丁羟胶丙烯酸酯大单体45％-80％、稀释剂0％-35％、交联剂10％-50％以及光引发剂1％-10％。以丁羟胶为原料,加入丙烯酰类化合物,在催化剂的作用下合成丁羟胶丙烯酸酯大单体。本发明还提供上述固体推进剂3D打印油墨的制备方法。将打印油墨放置于3D打印机料槽内,设置打印参数,启动打印得到固体推进剂样件。本发明丁羟胶基丙烯酸酯大单体的引入,使产品的玻璃化转变温度大大降低,断裂伸长率也有明显提高。(The invention relates to a solid propellant 3D printing ink based on butylated hydroxytoluene and a preparation method thereof, wherein the solid propellant 3D printing ink can be cured by ultraviolet light and comprises the following steps: 10-60% of butylated hydroxytoluene base photosensitive resin, 1-5% of dispersing agent, 25-70% of oxidant and 10-20% of metal fuel; the butadiene-based photosensitive resin comprises 45-80% of butadiene-based acrylate macromonomer, 0-35% of diluent, 10-50% of cross-linking agent and 1-10% of photoinitiator. The method is characterized in that the hydroxyl-terminated polybutadiene is used as a raw material, an acryloyl compound is added, and the hydroxyl-terminated polybutadiene acrylate macromonomer is synthesized under the action of a catalyst. The invention also provides a preparation method of the solid propellant 3D printing ink. And placing the printing ink in a feed trough of a 3D printer, setting printing parameters, and starting printing to obtain a solid propellant sample. The introduction of the butadiene-hydroxy-gum-based acrylate macromonomer greatly reduces the glass transition temperature of the product and obviously improves the elongation at break.)

1. The solid propellant 3D printing ink based on the butylated hydroxytoluene is characterized by comprising the following raw materials in percentage by mass:

10-60% of butylated hydroxytoluene base photosensitive resin, 1-5% of dispersing agent, 25-70% of oxidant and 10-20% of metal fuel;

the butadiene-based photosensitive resin comprises 45-80% of butadiene-based acrylate macromonomer serving as a raw material, 0-35% of diluent, 10-50% of cross-linking agent and 1-10% of photoinitiator.

2. The solid propellant 3D printing ink based on the butylated hydroxyaldehyde gum as claimed in claim 1, wherein the butylated hydroxyaldehyde gum acrylate macromonomer is prepared by the following method:

the method is characterized in that the hydroxyl-terminated polybutadiene is used as a raw material, an acryloyl compound is added, and the hydroxyl-terminated polybutadiene acrylate macromonomer is synthesized under the action of a catalyst.

3. The solid propellant 3D printing ink based on the butylated hydroxyaldehyde glue of claim 2, wherein the acryl based compound is one or more of acryloyl chloride, methacryloyl chloride, 3-isocyanuric acid propylene, isocyanuric ethyl acrylate, isocyanuric ethyl methacrylate, acrylic anhydride, methacrylic anhydride;

preferably, the catalyst is one or more of triethylamine, pyridine, 2-amino-4-ethylpyridine, 4-dimethylaminopyridine, tetrabutylammonium iodide, di-n-butyltin dilaurate and di-n-octyltin dilaurate;

preferably, the solvent is one or more of dichloromethane, acetone, trichloromethane, toluene, tetrahydrofuran, dimethyl sulfoxide, ethyl acetate and n-hexane;

preferably, the mass ratio of the hydroxyl-terminated rubber to the acrylic compound to the catalyst is 1: 0.362-0.683: 0.01-0.405.

4. The solid propellant 3D printing ink based on butylated hydroxyaldehyde gum as claimed in claim 2, wherein the butylated hydroxyaldehyde gum has a general formula shown in formula (I):

the hydroxyl-terminated polybutadiene acrylate macromonomer has a general formula shown as the following formula (II):

in the formulae (I), (II): the value of p + q + m + n is in the range of 40-70, and the value of m + n is in the range of 0-15.

5. The solid propellant 3D printing ink based on butylated hydroxyanisole as claimed in claim 1, wherein said diluent is one or more of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, isobutyl cinnamate, isooctyl acrylate, isooctyl methacrylate, ethoxyethoxyethyl acrylate, ethoxyethoxyethyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, bisphenol a dimethacrylate, isobornyl acrylate, hydroxypropyl acrylate, phenoxyethyl acrylate, ethylene glycol dimethacrylate, 1, 6-hexanediol diacrylate;

preferably, the crosslinking agent is one or more of trimethylolpropane triacrylate, ethoxylated trimethylolpropane triacrylate, 3-ethoxylated trimethylolpropane triacrylate, dipentaerythritol hexaacrylate, ethoxylated pentaerythritol tetraacrylate, pentaerythritol triacrylate, and propoxylated glycerol triacrylate;

preferably, the photoinitiator is one or more of TPO ultraviolet photoinitiator, 907 ultraviolet photoinitiator, ITX ultraviolet initiator, 184 ultraviolet initiator, 651 ultraviolet initiator, OMBB ultraviolet initiator, 819 ultraviolet initiator and 1173 ultraviolet initiator.

6. The solid propellant 3D printing ink based on butylated hydroxyanisole as claimed in claim 1, wherein the dispersant is one or more of BYK-W966, BYK-W980, sodium polyacrylate, ammonium polyacrylate.

7. The solid propellant 3D printing ink based on butylated hydroxyanisole as claimed in claim 1, wherein the oxidizer is ammonium perchlorate and the metal fuel is spherical aluminum powder.

8. The solid propellant 3D printing ink based on butylated hydroxyanisole as claimed in claim 7, wherein the ammonium perchlorate and spherical aluminum powder are solid powders, and the particle size is less than 500 μm.

9. The method for preparing the solid propellant 3D printing ink based on the butylated hydroxytoluene as claimed in claim 1, comprising the following steps:

mixing and uniformly stirring the butylated hydroxyacrylate acrylate macromonomer, the diluent, the cross-linking agent, the photoinitiator, the dispersant, the oxidant and the metal fuel according to a mass ratio, and defoaming in vacuum to obtain the solid propellant 3D printing ink.

10. A digital photo processing (D L P)3D printing forming method of the solid propellant 3D printing ink based on the butylated hydroxytoluene, comprising using the solid propellant 3D printing ink based on the butylated hydroxytoluene of claim 1, comprising the steps of:

and pouring the uniformly mixed solid propellant 3D printing ink into a material tank of a digital light processing (D L P)3D printer, adjusting printing parameters, starting printing, printing layer by layer, curing and accumulating, taking out and cleaning to obtain a solid propellant sample.

Technical Field

The invention belongs to the technical field of additive manufacturing, and particularly provides a solid propellant 3D printing ink based on butylated hydroxytoluene, a preparation method thereof and a D L P forming method.

Background

For solid propellant, the traditional casting forming process is mostly used at home and abroad at present, however, due to the high solid content, high viscosity and poor system fluidity of solid propellant slurry, the problems of poor product uniformity, defects and the like can occur in the casting process, the post-treatment is required manually, the operation is complex, and particularly, the safety is low. In addition, the casting process cannot realize the molding of solid propellants with complex structures such as hollow structures.

The 3D printing technique, also known as additive manufacturing, is an "additive manufacturing" process that continuously solidifies and deposits layers of material under the control of a digital model to ultimately form a three-dimensional object. Compared with the traditional casting forming technology, the 3D printing technology does not need a solid mold, can realize the precise manufacture of the solid propellant grain, and has a series of advantages of short manufacturing and design period, improvement of the automatic manufacturing process, precise manufacture of a complex structure, improvement of the safety and reliability and the like.

There have been reports on the application of 3D printing techniques to the fabrication of solid propellants. US patent document US9822045B2 discloses a solid propellant based on ABS thermoplastic, shaped using melt extrusion techniques; US patent document US10287218B2 discloses a solid propellant based on butylated hydroxyanisole shaped using extrusion techniques; chinese patent document CN107283826A discloses a solid propellant based on acrylate compounds, shaped using extrusion techniques. Chinese patent document CN107867961A discloses a method for improving the mechanical property of a butylated hydroxytoluene propellant and the butylated hydroxytoluene propellant prepared by the method.

However, in a plurality of 3D printing and forming methods, the extrusion forming technology has low forming precision, and is inconvenient for preparing a solid propellant product with a complex configuration; in addition, the solid propellant ink for 3D printing has high solid content, generally high viscosity, low printing speed by using an extrusion molding technology, easy generation of defects and unsatisfactory preparation effect. The ultraviolet curing 3D printing technology developed in recent years has the advantages of high forming precision, capability of manufacturing complex structures, high safety and reliability and the like. Chinese patent document CN109503299A discloses a solid propellant based on small molecule acrylate compounds, shaped using stereo photo-curing techniques. However, compared with the conventional hydroxyl-terminated solid propellant commonly used by the military, the small-molecular acrylate compound used in the patent has poor low-temperature resistance and lower elongation at break after the solid propellant product is formed.

Therefore, the development of the solid propellant 3D printing ink based on the butylated hydroxytoluene and adopting the ultraviolet curing molding technology can meet the requirement of accurately manufacturing a complex structure, and the solid propellant sample piece has the advantages of low temperature resistance and high elongation at break, so that the problem to be solved is urgently needed.

Disclosure of Invention

In view of the above problems of the prior art, the invention provides a solid propellant 3D printing ink based on a butylated hydroxytoluene, a preparation method thereof and an ultraviolet curing molding method, so that the butylated hydroxytoluene-based solid propellant printing ink is suitable for a digital light processing (D L P)3D printing technology, and a solid propellant sample with high size precision, high product density, low temperature resistance and high elongation at break can be safely prepared under normal temperature and normal pressure.

The technical scheme of the invention is as follows:

the solid propellant 3D printing ink based on the butylated hydroxytoluene comprises the following raw materials in percentage by mass:

10-60% of butylated hydroxytoluene base photosensitive resin, 1-5% of dispersing agent, 25-70% of oxidant and 10-20% of metal fuel;

the butadiene-based photosensitive resin comprises 45-80% of butadiene-based acrylate macromonomer serving as a raw material, 0-35% of diluent, 10-50% of cross-linking agent and 1-10% of photoinitiator.

According to the invention, preferably, the butadiene-hydroxy rubber acrylate macromonomer is prepared by the following method:

the method is characterized in that the hydroxyl-terminated polybutadiene is used as a raw material, an acryloyl compound is added, and the hydroxyl-terminated polybutadiene acrylate macromonomer is synthesized under the action of a catalyst.

According to the present invention, preferably, the preparation process of the butadiene-hydroxy acrylate macromonomer is as follows:

dissolving the butadiene-hydroxy glue and the acrylic compounds in a solvent according to a certain proportion, adding a catalyst, introducing inert gas for protection, reacting for 6-24h, dissolving and precipitating for three times by using a solvent-precipitant, and performing rotary evaporation to obtain the butadiene-hydroxy glue acrylate macromonomer.

According to the present invention, preferably, the acryl compound is one or more of acryloyl chloride, methacryloyl chloride, 3-isocyanato propylene, isocyano ethyl acrylate, isocyano ethyl methacrylate, acrylic anhydride and methacrylic anhydride.

According to the present invention, preferably, the catalyst is one or more of triethylamine, pyridine, 2-amino-4-ethylpyridine, 4-dimethylaminopyridine, tetrabutylammonium iodide, di-n-butyltin dilaurate and di-n-octyltin dilaurate.

According to the present invention, preferably, the solvent is one or more of dichloromethane, acetone, chloroform, toluene, tetrahydrofuran, dimethyl sulfoxide, ethyl acetate and n-hexane.

According to the invention, preferably, the precipitant is one or more of methanol, ethanol and water.

According to the invention, the reaction temperature is preferably selected between 0 ℃ and 90 ℃ depending on the starting materials.

According to the invention, the mass ratio of the hydroxyl-terminated rubber, the acrylic compound and the catalyst is preferably 1: 0.362-0.683: 0.01-0.405.

According to the invention, preferably, the hydroxyl-terminated polybutadiene is of the general formula shown in formula (I):

in formula (I): the value of p + q + m + n is in the range of 40-70, and the value of m + n is in the range of 0-15.

According to the present invention, preferably, the butylated hydroxyacrylate macromonomer has the general formula shown in formula (II) below:

in the formula (II): the value of p + q + m + n is in the range of 40-70, and the value of m + n is in the range of 0-15.

According to the present invention, preferably, the diluent is one or more of methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, isobutyl cinnamate, isooctyl acrylate, isooctyl methacrylate, ethoxyethoxyethyl acrylate, ethoxyethoxyethoxyethyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, bisphenol a dimethacrylate, isobornyl acrylate, hydroxypropyl acrylate, phenoxyethyl acrylate, ethylene glycol dimethacrylate, 1, 6-hexanediol diacrylate.

According to the present invention, preferably, the cross-linking agent is one or more of trimethylolpropane triacrylate, ethoxylated trimethylolpropane triacrylate, 3-ethoxylated trimethylolpropane triacrylate, dipentaerythritol hexaacrylate, ethoxylated pentaerythritol tetraacrylate, pentaerythritol triacrylate, and propoxylated glycerol triacrylate.

According to the present invention, preferably, the photoinitiator is one or more of TPO uv initiator, 907 uv initiator, ITX uv initiator, 184 uv initiator, 651 uv initiator, OMBB uv initiator, 819 uv initiator and 1173 uv initiator.

According to the invention, preferably, the dispersant is one or more of BYK-W966, BYK-W980, sodium polyacrylate and ammonium polyacrylate.

According to the invention, it is preferred that the oxidant is ammonium perchlorate.

According to the present invention, preferably, the metal fuel is spherical aluminum powder.

According to the invention, preferably, the ammonium perchlorate and the spherical aluminum powder are both solid powder, and the particle size of the solid powder is less than 500 mu m.

The invention also provides a preparation method of the solid propellant 3D printing ink based on the butylated hydroxytoluene, which comprises the following steps:

mixing and uniformly stirring the butylated hydroxyacrylate acrylate macromonomer, the diluent, the cross-linking agent, the photoinitiator, the dispersant, the oxidant and the metal fuel according to a mass ratio, and defoaming in vacuum to obtain the solid propellant 3D printing ink.

The invention also provides a digital light processing (D L P)3D printing and forming method of the solid propellant 3D printing ink based on the butylated hydroxytoluene, which comprises the following steps:

and pouring the uniformly mixed solid propellant 3D printing ink into a material tank of a digital light processing (D L P)3D printer, adjusting printing parameters, starting printing, printing layer by layer, curing and accumulating, taking out and cleaning to obtain a solid propellant sample.

The invention has the following advantages:

1. according to the invention, through esterification reaction, hydroxyl functional groups of the hydroxyl-terminated polybutadiene rubber are converted into double-bond-containing acryloyl functional groups, so that free radical curing reaction under light irradiation can be carried out, and the hydroxyl-terminated polybutadiene rubber acrylate photocuring macromonomer capable of being used for ultraviolet 3D printing can be obtained.

2. The introduction of the butadiene-hydroxy-gum-based acrylate macromonomer greatly reduces the glass transition temperature of the product, and the final solid propellant sample has good low-temperature resistance and obviously improved elongation at break.

3. The invention uses digital light processing (D L P)3D printing technology to prepare the solid propellant product, has a series of advantages of short manufacturing period, precise manufacturing of complex structure, improvement of automatic manufacturing process and the like, and greatly improves the production safety compared with the traditional casting process.

Drawings

FIG. 1 is a nuclear magnetic spectrum of the butylated hydroxytoluene of example 1.

FIG. 2 shows the IR spectra of the butylated hydroxyaldehyde glue a of example 1 and the prepared butylated hydroxyaldehyde glue acrylate macromonomer b.

Fig. 3 is a 3D printed sample strip of the solid propellant based on butylated hydroxyanisole prepared in example 6.

FIG. 4 is a DMA test graph of the product of example 6.

Detailed Description

The invention will be further explained with reference to specific embodiments, without limiting the invention.