Plant fiber surface treatment technology

Abstract

The invention belongs to the technical field of concrete, and particularly relates to a plant fiber surface treatment technology. The method comprises the following steps: firstly, carrying out alkali treatment on plant fibers, then, carrying out mineralization layer growth on the surfaces of the plants by using sodium silicate and tetraethoxysilane, and finally, forming a stable net-shaped structure through water-soluble protein cross-linked mineralizer covalent bonds. A stable mineralization layer can be formed on the surfaces of the plant fibers, so that the combination effect of the plant fibers and the concrete is improved, and the strength of the concrete after the plant fibers are compounded with the concrete is improved. Meanwhile, the net-shaped structure can effectively improve the toughness of the mineralization layer, the mineralization layer is prevented from being damaged when being mixed and stirred with concrete, the integrity of the plant fibers and the concrete during mixing is guaranteed, and the material is more durable.

Description

Technical Field

[0001] The invention belongs to the technical field of concrete, and in particular relates to a plant fiber surface treatment technology for improving the bonding effect with concrete. Background Art

[0002] Concrete products are brittle materials. The application of fiber reinforcement technology can prevent the propagation of microcracks in the early stage of formation through the fiber "bridging effect", and can give fiber cement composite materials toughness. Therefore, fiber reinforced concrete can be widely used in the construction field with its excellent performance.

[0003] Plant fibers are generally used as reinforcing fibers for concrete. However, the chemical composition of plant fibers is mostly acidic and neutral, while the chemical composition of cement is alkaline. The contact between the two will form a third phase micro-interface, resulting in a decrease in the overall performance of fiber concrete. Therefore, people need to improve the bonding ability of the plant fiber and concrete interface to prepare high-performance plant fiber cement composites. Summary of the invention

[0004] The purpose of the present invention is to provide a plant fiber surface treatment technology, which can effectively reduce the charge type and chemical structure on the plant fiber surface by mineralizing the plant fiber surface to form a mineralized layer with silicon-calcium compounds as the main components, thereby improving the mechanical properties and other qualities of plant fiber concrete. At the same time, the present invention performs toughening treatment on the mineralized layer to improve the toughness of the mineralized layer and the durability of the plant fiber. The technical scheme of the present invention is as follows:

[0005] A plant fiber surface treatment technology comprises the following steps:

[0006] S1. crushing the plant fiber;

[0007] S2. The crushed plant fiber is soaked in a mixed solution of calcium hydroxide and sodium hydroxide, the soaked plant fiber is filtered, dried and collected;

[0008] S3. Soak the dried plant fiber in a solution of sodium silicate, tetraethoxysilane and calcium hydroxide for 1-4h;

[0009] S4. Adding calcium phosphate, a cationic surfactant, a water-soluble protein and 2-methylimidazole to the solution of S3, and continuing the soaking treatment;

[0010] S5. Filter, dry and collect to obtain surface mineralized plant fibers.

[0011] As an improvement, in step S2, the content of calcium hydroxide in the mixed solution of calcium hydroxide and sodium hydroxide is 4-6%, and the content of sodium hydroxide is 0.1-0.2%.

[0012] As an improvement, the soaking time in step S2 is 5-10 days.

[0013] As an improvement, the contents of the raw materials in the solution in step S3 are: 0.1-0.2% sodium silicate, 2-5% tetraethoxysilane, and 1-3% calcium hydroxide solution.

[0014] As an improvement, the added amounts of the raw materials in step S4 are: 0.3-0.8% calcium phosphate, 0.5-0.8% cationic surfactant, 0.3-0.6% water-soluble protein, and 0.05-0.2% 2-methylimidazole.

[0015] As an improvement, the soaking treatment time in step S4 is 3-4 days.

[0016] The technical advantages of the present invention are:

[0017] 1. The present invention performs targeted alkali treatment on small molecules present in plant fibers, and after the treatment, the content of precipitates on the surface of plant fibers can be effectively reduced. Calcium hydroxide is used as an alkali source during alkali treatment, and after the treatment, it can react with carbon dioxide in the air and deposit on the surface of the plant fibers to generate initial reaction activation sites. At the same time, using calcium hydroxide as an alkali source can reduce the impact on the environment, absorb carbon dioxide in the air, and will not pollute the environment.

[0018] 2. The present invention uses sodium silicate and tetraethoxysilane to grow a mineralized layer on the plant surface, which can form a stable mineralized layer on the surface of plant fibers, thereby improving the bonding effect between plant fibers and concrete, and improving the strength of concrete after compounding them into concrete.

[0019] 3. The present invention forms a stable network structure by cross-linking mineralized substances with water-soluble proteins through covalent bonds, which can effectively improve the toughness of the mineralized layer, avoid damage to the mineralized layer when mixed with concrete, ensure the integrity of the plant fiber when mixed with concrete, and make the material more durable. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the morphology of plant fiber without surface mineralization treatment.

[0021] Figure 2 It is the morphology of plant fiber after mineralization treatment. DETAILED DESCRIPTION

[0022] The present invention is described in detail and specifically by specific examples below to provide a better understanding of the present invention, but the following examples do not limit the protection scope of the present invention.

[0023] Example 1

[0024] This embodiment discloses a plant fiber surface treatment technology, comprising the following steps:

[0025] S1. crushing the plant fibers.

[0026] S2. Soak the crushed plant fibers in a mixed solution pool of 5% calcium hydroxide and 0.1% sodium hydroxide for 5-10 days. After soaking, filter the plant fibers, dry them in the sun, and collect them.

[0027] S3. Soak the dried plant fiber in a pool of 0.1% sodium silicate, 3% tetraethoxysilane and 1% calcium hydroxide solution for 2 hours.

[0028] S4. Add 0.5% calcium phosphate, 0.5% cationic surfactant, 0.5% water-soluble protein and 0.1% 2-methylimidazole to the solution pool of S3, and continue the immersion treatment for 3 days.

[0029] S5. Filter, dry and collect to obtain surface mineralized plant fibers.

[0030] The present invention also provides a plurality of embodiments and comparative examples, and the processing methods of the embodiments and comparative examples are the same as those of embodiment 1, except that the amount of each raw material after step S3 is changed. The specific materials are shown in the following table:

[0031] Table 1 Raw material dosage of each embodiment and control example

[0032]

[0033] The products of each embodiment and control example were tested, and it was found that the toughness of embodiments 1-5 was significantly greater than that of control examples 1 and 2. In addition, a large amount of fine sand precipitated at the bottom of the pool where control examples 1 and 2 were immersed, indicating that a relatively complete mineralized layer was not formed on the surface of the plant fiber.

[0034] The specific embodiments of the present invention are described in detail above, but they are only examples, and the present invention is not equivalent to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions made to the present invention are also within the scope of the present invention. Therefore, the equalization changes and modifications made without departing from the spirit and scope of the present invention should be included in the scope of the present invention.

Claims

1. A plant fiber surface treatment technology, characterized in that: The steps include: S1. crushing the plant fiber; S2. The crushed plant fiber is soaked in a mixed solution of calcium hydroxide and sodium hydroxide, the soaked plant fiber is filtered, dried and collected; S3. Soak the dried plant fiber in a solution of sodium silicate, tetraethoxysilane and calcium hydroxide for 1-4h; S4. Adding calcium phosphate, a cationic surfactant, a water-soluble protein and 2-methylimidazole to the solution of S3, and continuing the soaking treatment; S5. Filter, dry and collect to obtain surface mineralized plant fibers.

2. A plant fiber surface treatment technology according to claim 1, characterized in that: In step S2, the content of calcium hydroxide in the mixed solution of calcium hydroxide and sodium hydroxide is 4-6%, and the content of sodium hydroxide is 0.1-0.2%.

3. A plant fiber surface treatment technology according to claim 2, characterized in that: The soaking time in step S2 is 5-10 days.

4. A plant fiber surface treatment technology according to claim 1, characterized in that: The contents of the raw materials in the solution in step S3 are: 0.1-0.2% sodium silicate, 2-5% tetraethoxysilane, and 1-3% calcium hydroxide solution.

5. The plant fiber surface treatment technology according to claim 1, characterized in that: The added amounts of the raw materials in step S4 are: 0.3-0.8% calcium phosphate, 0.5-0.8% cationic surfactant, 0.3-0.6% water-soluble protein, and 0.05-0.2% 2-methylimidazole.

6. A plant fiber surface treatment technology according to claim 1, characterized in that: The soaking treatment time in step S4 is 3-4 days.

Images