A multi-element mineral compound, a preparation method and application thereof

Abstract

The application discloses a preparation method of a multi-element mineral compound, which comprises the following steps: preparing calcium carbonate ion oligomers and calcium phosphate ion oligomers; uniformly mixing the calcium carbonate ion oligomers and the calcium phosphate ion oligomers, stirring, centrifugal separation, washing, and obtaining calcium carbonate and calcium phosphate composite gel; and drying the calcium carbonate and calcium phosphate composite gel to obtain the multi-element mineral compound. The application further discloses the multi-element mineral compound prepared by the above preparation method and application thereof. The preparation process is simple, and the cost is low. The multi-element mineral compound prepared by the preparation process has uniform structure, adjustable chemical components and properties, single and adjustable phase transition temperature, and good mechanical properties. The hardness of the multi-element mineral compound can reach 0.85+ / -0.08 GPa, which is 142% and 102% higher than that of amorphous calcium carbonate and amorphous calcium phosphate respectively. The multi-element mineral compound has wide application prospect in the fields of cement fillers, biological bone cement and tooth repair.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of inorganic ionic minerals, in particular to a multi-mineral compound and a preparation method and application thereof. BACKGROUND

[0002] Minerals, especially inorganic ionic minerals, play an irreplaceable role in the long history of human society. Among them, calcium carbonate and calcium phosphate are two of the most typical biological minerals, which play an important role in production and life. Alloy materials can integrate two or more metal elements together and achieve better performance than any single component through component regulation. Therefore, if the preparation method of alloy can be used to prepare multi-mineral materials, it will have important significance for the development of mineralogy and inorganic materials.

[0003] Multi-mineral compounds refer to compounds composed of two or more different mineral components. Due to the tunability of chemical components, the material is endowed with different chemical properties. However, due to the limitation of traditional nucleation and growth theory, the ions of different mineral components tend to form their own critical crystal nuclei first, and it is difficult to achieve uniform mixing at the molecular scale between different mineral components, which is a great challenge for the preparation of multi-mineral compounds.

[0004] Inorganic ionic oligomers are ultra-small inorganic monomers that can construct structure-continuous inorganic materials at an ultra-small scale. Patent document with publication number CN112980120B discloses a preparation method of ionic mineral plastic, comprising: molecularly modifying polyvinyl alcohol solution with sodium alginate solution to obtain sodium alginate-modified polyvinyl alcohol linear polymer solution; adding calcium phosphate ionic oligomers to the sodium alginate-modified polyvinyl alcohol linear polymer solution, stirring uniformly, and then centrifuging the obtained emulsion to obtain a precursor gel of ionic mineral plastic; and the precursor gel of ionic mineral plastic is molded or naturally dried to obtain ionic mineral plastic. The ionic mineral plastic prepared by using calcium phosphate ionic oligomers can be used as completely degradable plastic.

[0005] Patent document with publication number CN110157132B discloses a high-strength organic-inorganic homogeneous composite material, which comprises 70-90wt% of polyacrylamide and 10-30wt% of calcium phosphate ionic compound, wherein the calcium phosphate ionic compound is a calcium phosphate ionic oligomer. The organic-inorganic homogeneous composite material prepared by the invention has excellent hardness and elastic modulus, and can be used as transparent optical devices and high-strength structural materials.

[0006] The method for preparing the composite material by using the inorganic ion oligomer points out the direction for preparing the multi-mineral compound. Therefore, if the method for preparing the alloy material is combined with the inorganic ion oligomer, it is of great significance to prepare a multi-mineral compound with uniform structure, adjustable chemical components and properties at the molecular scale. SUMMARY

[0007] In view of the deficiencies of the prior art, the present application provides a method for preparing a multi-mineral compound. The method is characterized by cross-linking and drying the prepared calcium carbonate ion oligomer and calcium phosphate ion oligomer to obtain the multi-mineral compound. The preparation process is simple, and the cost is low, which can be used for large-scale industrial production.

[0008] A method for preparing a multi-mineral compound, comprising the following steps:

[0009] (1) preparing calcium carbonate ion oligomer and calcium phosphate ion oligomer;

[0010] (2) mixing the calcium carbonate ion oligomer and the calcium phosphate ion oligomer, stirring, centrifugal separation, washing to obtain a calcium carbonate and calcium phosphate composite gel, drying the calcium carbonate and calcium phosphate composite gel to obtain the multi-mineral compound.

[0011] The present application first prepares inorganic monomers of calcium carbonate ion oligomer and calcium phosphate ion oligomer, then uniformly mixes the two inorganic monomers, and forms a composite gel of calcium carbonate and calcium phosphate through co-crosslinking, and finally forms a continuous inorganic bulk material after drying.

[0012] Preferably, in step (1), the method for preparing the calcium carbonate ion oligomer is as follows: triethylamine is used as an end-capping agent, calcium salt is used as a cation source, and carbon dioxide is used as an anion source, which are added to an organic solvent to react at room temperature to obtain the calcium carbonate ion oligomer.

[0013] Preferably, the molar ratio of triethylamine to calcium ions is 1:20-100.

[0014] Preferably, in step (1), the method for preparing the calcium phosphate ion oligomer is as follows: triethylamine is used as an end-capping agent, calcium salt is used as a cation source, and phosphoric acid is used as an anion source, which are added to an organic solvent to react at room temperature to obtain the calcium phosphate ion oligomer.

[0015] Preferably, the molar ratio of triethylamine to calcium ions is 1:20-100.

[0016] In the preparation of the calcium carbonate ion oligomer and the calcium phosphate ion oligomer, a slightly excessive amount of the anion source is added to make the Ca 2+ be completely combined.

[0017] Preferably, the calcium salt comprises calcium chloride dihydrate.

[0018] Preferably, the organic solvent comprises ethanol, propanol or butanol.

[0019] Preferably, in step (2), the stirring rate is greater than 300 rpm, and the stirring time is 12-48 h.

[0020] Preferably, in step (2), the centrifugal separation is performed 2-5 times, wherein the rate of the last centrifugal separation is 15000-20000 rpm, and the rates of the rest centrifugal separations are 6000-10000 rpm.

[0021] The present application employs centrifugal separation to remove triethylamine, organic solvent and unreacted phosphoric acid.

[0022] The low-speed centrifugal separation in the early stage of the reaction is to prevent the gel from being too dense to be washed, and the high-speed centrifugal separation in the last stage can obtain further dense calcium carbonate and calcium phosphate composite gel.

[0023] Preferably, in step (2), the drying time is more than 24 h.

[0024] The obtained calcium carbonate and calcium phosphate composite gel is dried to obtain a bulk material with uniform structure, adjustable chemical composition and properties at the molecular scale, i.e. a multi-mineral compound.

[0025] Preferably, in step (2), in the multi-mineral compound: 16%< molar ratio of C / Ca < 91%, or 6%< molar ratio of P / Ca < 56%.

[0026] The present application can adjust the final chemical composition of the calcium carbonate and calcium phosphate multi-mineral compound by adjusting the mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer.

[0027] The present application also provides a multi-mineral compound prepared by the above preparation method.

[0028] The multi-mineral compound has a fixed chemical formula: Ca(CO3) x (PO4) 2(1-x) / 3 , wherein 0.16 < x < 0.91.

[0029] The multi-mineral compound of the present application has optical transparency in macroscopic view, and the carbonate, phosphate and calcium ion are uniformly distributed at the molecular scale and uniformly change with the change of the chemical composition.

[0030] The polymineral compound has a single phase transition temperature, balances the crystallization temperature of calcium carbonate and calcium phosphate, and changes the chemical composition, so that the single phase transition temperature also changes.

[0031] The application further provides application of the polymineral compound in cement fillers, biological bone cement and tooth repair.

[0032] Compared with the prior art, the application has at least the following beneficial effects:

[0033] (1) The application first uses triethylamine as an end-capping agent to prepare inorganic monomers of calcium carbonate and calcium phosphate ion oligomers, and the prepared calcium carbonate ion oligomers and calcium phosphate ion oligomers are crosslinked and dried to prepare the polymineral compound. The preparation process is simple, low in cost, and can be used for large-scale industrial production.

[0034] (2) The carbonate, phosphate and calcium ions in the polymineral compound are uniformly distributed on a molecular scale and uniformly change with the change of the components.

[0035] (3) The application can uniformly integrate the chemical components of calcium carbonate and calcium phosphate on a molecular scale, the carbonate and phosphate form interaction through the calcium ions, the strong interaction enables the prepared polymineral compound to have a single and adjustable phase transition temperature, and balances the crystallization temperature of calcium carbonate and calcium phosphate.

[0036] (4) The polymineral compound has good mechanical properties, the hardness can reach 0.85±0.08GPa, is 142% and 102% higher than that of amorphous calcium carbonate and amorphous calcium phosphate respectively, and has a wide application prospect in the fields of cement fillers, biological bone cement and tooth repair. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 The figure is a flowchart for preparing the polymineral compound of Example 1.

[0038] Figure 2 The figure is an ICP-OES graph of the polymineral compound prepared in Example 1.

[0039] Figure 3 The figure is a REDOR NMR graph of the polymineral compound prepared in Example 1. Figure 3The mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer in the polymineral compound of A is 9:7; Figure 3 The mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer in the polymineral compound of B is 3:1; Figure 3 The mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer in the polymineral compound of C is 7:1; Figure 3 The mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer in the polymineral compound of D is 27:1.

[0040] Figure 4 DSC diagram of the polymineral compound prepared in Example 1.

[0041] Figure 5 Mechanical property diagram of the polymineral compound prepared in Example 1. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described below in combination with the drawings and examples. It should be understood that the specific implementation manner described herein is only used to explain the present application, and does not limit the protection scope of the present application.

[0043] Example 1

[0044] The preparation method of the polymineral compound of the present embodiment is shown in Figure 1 The specific process is as follows:

[0045] Preparation of calcium carbonate ion oligomer: prepare calcium chloride ethanol solution, 0.2 g of calcium chloride dihydrate is dissolved in 100 mL of anhydrous ethanol, 9.5 mL of triethylamine is added, stirring for 30 min, then passing carbon dioxide gas for 10 min, the solution changes from colorless and transparent to milky white, and then quickly turns to light blue, at this time the calcium carbonate ion oligomer is obtained.

[0046] Preparation of calcium phosphate ion oligomer: prepare calcium chloride ethanol solution, 0.2 g of calcium chloride dihydrate is dissolved in 80 mL of anhydrous ethanol, 4.5 mL of triethylamine is added, stirring for 30 min, then 70 μL of phosphoric acid is dissolved in 20 mL of anhydrous ethanol, 5 mL of triethylamine is added, stirring for 30 min, to obtain the ethanol solution of phosphoric acid, then the ethanol solution of phosphoric acid is added dropwise to the calcium chloride ethanol solution, stirring for 1 h, to obtain the calcium phosphate ion oligomer.

[0047] Preparation of multi-mineral compound: different molar mass of calcium carbonate ion oligomer and calcium phosphate ion oligomer were mixed uniformly, the molar ratio of the two was 1:3, 3:4, 9:7, 2:1, 3:1, 9:2, 7:1, 12:1, 27:1, respectively, and stirred vigorously for 24 h, then washed with anhydrous ethanol at a speed of 8000 rpm for three times, and finally centrifuged at a speed of 20000 rpm to obtain a composite gel of calcium carbonate and calcium phosphate, which was placed in a vacuum dryer for drying for 48 h, thereby obtaining a multi-mineral compound containing calcium carbonate and calcium phosphate components.

[0048] As shown in Figure 1 , the prepared multi-mineral compound has the property of optical transparency.

[0049] Figure 2 The elemental analysis (ICP-OES) graph of the multi-mineral compound prepared in this example shows that the multi-mineral compound of this example has a fixed molecular formula: Ca(CO3) x (PO4) 2(1-x) / 3 , and the chemical composition is adjustable. By changing the molar ratio of calcium carbonate and calcium phosphate, the molar ratio of P / Ca in the multi-mineral compound can be completely adjusted from 6% to 56%, and the molar ratio of C / Ca can be completely adjusted from 16% to 91%.

[0050] Figure 3 The solid-state nuclear magnetic rotating echo double resonance (REDOR NMR) graph of the multi-mineral compound prepared in this example shows that Figure 3 the mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer in the multi-mineral compound of A is 9:7; Figure 3 the mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer in the multi-mineral compound of B is 3:1; Figure 3 the mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer in the multi-mineral compound of C is 7:1; Figure 3 the mixed molar ratio of calcium carbonate ion oligomer and calcium phosphate ion oligomer in the multi-mineral compound of D is 27:1. It can be seen that Figure 3 there is a very strong coupling interaction between carbon atoms and phosphorus atoms in the multi-mineral compound prepared in this example at the molecular scale, the average distance between carbon atoms and phosphorus atoms is 0.3-0.6 nm, and there are a large number of bridge bonds of PO4 3- -Ca 2+ -CO3 2- , which further illustrates that the carbonate, phosphate and calcium ions achieve a uniform composite at the molecular scale, and the structure is very uniform.

[0051] Figure 4The differential scanning calorimetry graph of the multi-mineral compound prepared for the present embodiment has a single phase transition temperature due to the uniformity of the material at the molecular scale, and the phase transition temperature is also adjustable with the change of the chemical composition.

[0052] Figure 5 The mechanical property graph of the multi-mineral compound prepared for the present embodiment shows that the hardness of the multi-mineral compound can reach 0.85±0.08 GPa when the mixed molar ratio of calcium carbonate ionic oligomers and calcium phosphate ionic oligomers is 7:1, which is 142% and 102% higher than that of amorphous calcium carbonate and amorphous calcium phosphate, respectively.

Claims

1. A method for producing a polymineral compound, characterized by, The method comprises the following steps: (1) preparing calcium carbonate ionic oligomers and calcium phosphate ionic oligomers; (2) mixing the calcium carbonate ionic oligomers and the calcium phosphate ionic oligomers, stirring, centrifugal separation, washing, obtaining calcium carbonate and calcium phosphate composite gel, drying the calcium carbonate and calcium phosphate composite gel, and obtaining a multi-mineral compound.

2. The production method according to claim 1, characterized by, The method for preparing the calcium carbonate ionic oligomers comprises the following steps: adding triethylamine as a capping agent, calcium salt as a cation source, and carbon dioxide as an anion source into an organic solvent, and reacting at room temperature to obtain the calcium carbonate ionic oligomers.

3. The production method according to claim 2, characterized by, The molar ratio of the triethylamine to the calcium ions is 1:20-100.

4. The production method according to claim 1, characterized by, The method for preparing the calcium phosphate ionic oligomers comprises the following steps: adding triethylamine as a capping agent, calcium salt as a cation source, and phosphoric acid as an anion source into an organic solvent, and reacting at room temperature to obtain the calcium phosphate ionic oligomers.

5. The preparation method according to claim 4, characterized in that The molar ratio of the triethylamine to the calcium ions is 1:20-100.

6. The method of claim 1, wherein, In the step (2), the stirring rate is greater than 300 rpm, and the stirring time is 12-48 h.

7. The preparation method according to claim 1, characterized in that In the step (2), the drying time is more than 24 h.

8. The method of claim 1, wherein, In the step (2), in the multi-mineral compound, the molar ratio of P / Ca is 6%-56%, or the molar ratio of C / Ca is 16%-91%.

9. The multi-mineral compound prepared by the method according to any one of claims 1-8.

10. The multi-mineral compound according to claim 9, which is used in the fields of cement fillers, biological bone cements, and tooth repair.

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