Preparation method of konjac glucomannan modified pea starch glass fiber impregnating compound

Abstract

The invention belongs to the technical field of glass fiber surface treating agents, and discloses a preparation method of a konjac glucomannan modified pea starch glass fiber impregnating compound, which comprises the following steps: adding water into pea starch, and gelatinizing at 85 DEG C for 30 minutes to prepare a pea starch solution; the preparation method comprises the following steps: adding water into konjac glucomannan, and stirring and dissolving at 60 DEG C to prepare a konjac glucomannan solution; mixing the pea starch solution and the konjac glucomannan solution according to a mass ratio of 4: 1, adding a silane coupling agent, and carrying out esterification grafting reaction at 75 DEG C for 1 hour to obtain a mixed solution; and adding a plasticizer, a lubricant and an antistatic agent into the mixed solution, and homogenizing at a high speed to obtain the impregnating compound. According to the preparation method, a pea starch and konjac glucomannan full bio-based system is adopted, the impregnating compound is prepared through a water-phase esterification reaction, the process is simple, the reaction condition is mild, a three-dimensional network is formed through esterification crosslinking of konjac glucomannan linear molecules and pea starch branched chains, and the compactness of a film layer is improved.

Description

Technical Field

[0001] This invention belongs to the technical field of glass fiber surface treatment agents, specifically relating to a method for preparing a konjac glucomannan-modified pea starch glass fiber impregnating agent. Background Technology

[0002] Under the "dual-carbon" strategy, the fiberglass industry faces pressure to transform towards environmental protection. Traditional petroleum-based sizing agents (such as epoxy emulsions and polyurethane) rely on non-renewable resources, resulting in high carbon emissions during production and difficulty in biodegradation, thus imposing a heavy environmental burden. Among existing bio-based sizing agents, starch-based film-forming agents have attracted attention due to their wide availability, renewability, and biodegradability; however, different starch-based materials exhibit significant performance differences.

[0003] Corn starch, as a traditional raw material, has poor film-forming properties, is prone to retrogradation, and lacks water resistance and mechanical strength; although cassava starch has high viscosity, its film-forming properties are brittle and its adhesion is weak. Compared with other starches, pea starch has the following significant advantages: (1) High amylose content: The amylose content of pea starch (about 35%~65%) is significantly higher than that of corn starch (about 25%~30%) and cassava starch (about 17%~20%), making its film more dense, harder, and more water-resistant; (2) Excellent film-forming properties and flexibility: The molecular structure of pea starch is regular, the film formed is uniform and has strong adhesion, and its flexibility is better than that of corn starch and cassava starch, making it more suitable for high-speed drawing process; (3) Low retrogradation tendency: Pea starch has a slow retrogradation rate after gelatinization, and the system has good stability, which is conducive to the storage and construction of the wetting agent; (4) Environmental protection and sustainability: Peas are a rotation crop with strong carbon fixation ability during planting, and its starch production process has low energy consumption and a smaller carbon footprint than corn starch processing; (5) Good compatibility: Pea starch has excellent compatibility with natural polysaccharides and is easy to construct a three-dimensional network structure through esterification, grafting and other methods to improve comprehensive performance.

[0004] However, pure pea starch sizing agents still suffer from problems such as insufficient film-forming strength, high fiber breakage rate, and poor process adaptability. Existing modified starch sizing agents mostly use modifiers such as gelatin, chitosan, and silica gel. Although they have some effect, they still have problems such as complex processes, high costs, or reliance on chemical cross-linking agents. Summary of the Invention

[0005] In view of the above-mentioned defects or improvement needs of existing technologies, this invention aims to provide an environmentally friendly, high-performance, and fully bio-based glass fiber sizing agent, which solves the problems of high pollution of existing petroleum-based sizing agents, poor film-forming properties of traditional starch sizing agents, and complex processes, and realizes the green and low-carbon transformation of glass fiber sizing agents.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for preparing a konjac glucomannan-modified pea starch glass fiber impregnating agent is provided, the method comprising the following steps: S100: Pea starch is gelatinized with water at 85°C for 30 minutes to obtain a pea starch solution; S200: Konjac glucomannan is dissolved in water at 60°C by stirring to obtain konjac glucomannan solution; S300: Mix pea starch solution and konjac glucomannan solution at a mass ratio of 4:1, add silane coupling agent, and carry out esterification grafting reaction at 75°C for 1 hour to obtain a mixed solution; S400: Plasticizer, lubricant and antistatic agent are added to the mixture, and the mixture is homogenized at high speed to obtain the wetting agent.

[0007] Furthermore, the pea starch solution in S100 has a mass percentage concentration of 8-12%.

[0008] Furthermore, the mass percentage concentration of the konjac glucomannan solution in S200 is 1~2%.

[0009] Furthermore, the silane coupling agent described in S300 is γ-aminopropyltriethoxysilane, and its addition amount is 0.5~1% of the total mass of the pea starch solution and the konjac glucomannan solution.

[0010] Furthermore, the plasticizer described in S400 is glycerin, and its addition amount is 3 to 5% of the mass of the mixture.

[0011] Furthermore, the lubricant described in S400 is a plant wax, and its addition amount is 1 to 2% of the mass of the mixture.

[0012] Furthermore, the antistatic agent described in S400 is choline dihydrogen phosphate, and its addition amount is 0.5~1% of the mass of the mixture.

[0013] According to a second aspect of the present invention, a glass fiber sizing agent is provided, which is prepared according to the preparation method of konjac glucomannan-modified pea starch glass fiber sizing agent as described above.

[0014] Furthermore, the glass fiber impregnating agent has a solid content of 12-15% and a viscosity of 150-300 mPa·s.

[0015] According to a third aspect of the present invention, an application of a glass fiber sizing agent is provided, wherein the glass fiber sizing agent is applied in the field of glass fiber furnace drawing or textile processing.

[0016] Compared with the prior art, the present invention can achieve the following beneficial effects: 1. This invention uses a fully bio-based system of pea starch and konjac glucomannan to prepare an impregnating agent through an aqueous phase esterification reaction. It does not require organic solvents or toxic crosslinking agents, and the process is simple and the reaction conditions are mild, achieving high biodegradability and low carbon emissions.

[0017] 2. This invention improves the film density by forming a three-dimensional network through the esterification and cross-linking of linear molecules of konjac glucomannan with branched chains of pea starch. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0019] Konjac glucomannan, as a natural and renewable polysaccharide, possesses linear molecular chains and abundant hydroxyl groups, exhibiting excellent film-forming properties. Furthermore, the acetyl groups in its molecules provide natural hydrophobicity, reducing the need for recalcitrant additives such as those containing fluorine or silicon. This invention combines konjac glucomannan with pea starch to construct a green impregnation system that is high-strength, flexible, water-resistant, and fully biodegradable, possessing significant industrial value and environmental implications.

[0020] This invention provides a method for preparing a konjac glucomannan-modified pea starch glass fiber impregnating agent, the method comprising the following steps: (1) Add water to pea starch and gelatinize it at 85°C for 30 minutes to obtain a pea starch solution with a mass percentage concentration of 8~12%; (2) Dissolve konjac glucomannan in water at 60°C by stirring, and prepare a konjac glucomannan solution with a mass percentage concentration of 1-2%. (3) Mix pea starch solution and konjac glucomannan solution at a mass ratio of 4:1, add 0.5~1% of the total mass of the two solutions of bio-based silane coupling agent γ-aminopropyltriethoxysilane, and carry out esterification grafting reaction at 75°C for 1 hour to form a mixture with a three-dimensional network structure. (4) Add 3-5% of the bio-based plasticizer glycerin, 1-2% of the renewable lubricant plant wax and 0.5-1% of the environmentally friendly antistatic agent choline dihydrogen phosphate to the mixture system, and form a uniform and stable wetting agent system after high-speed homogenization. Adjust the solid content of the system to 12-15% to obtain the finished wetting agent.

[0021] The glass fiber sizing agent prepared according to the above method has a viscosity of 150~300 mPa·s, forms a dense film, has strong adhesion, and has a low moisture absorption rate (which can be reduced to 19.69%). When applied to the glass fiber tank furnace drawing field, it can achieve high-speed drawing (≥60 m / s), and when applied to the textile processing field, it can improve the mechanical properties of yarn.

[0022] This invention uses a fully bio-based formula with raw materials derived from renewable resources. The carbon footprint of the prepared wetting agent is reduced by more than 60% compared to petroleum-based wetting agents, and VOC emissions are reduced by 85%. The wetting agent film can be completely degraded in the natural environment within 90 days, with no microplastic pollution. Example

[0023] This embodiment provides a method for preparing a konjac glucomannan-modified pea starch glass fiber impregnating agent, the method comprising the following steps: (1) Add water to pea starch and gelatinize it at 85°C for 30 minutes to obtain a pea starch solution with a mass percentage concentration of 10%; (2) Dissolve konjac glucomannan in water at 60°C by stirring, and prepare a konjac glucomannan solution with a mass percentage concentration of 1.5%; (3) Mix pea starch solution and konjac glucomannan solution at a mass ratio of starch solution: konjac solution = 4:1, add 0.8% of γ-aminopropyltriethoxysilane (KH-550) of the total mass of the two solutions, and carry out esterification grafting reaction at 75°C for 1 hour to form a mixture with a three-dimensional network structure. (4) Add 4% glycerol, 1.5% vegetable wax and 0.8% choline dihydrogen phosphate to the mixture system, and obtain glass fiber sizing agent after high-speed homogenization.

[0024] The glass fiber impregnating agent prepared in Example 1 was subjected to performance tests. The test results were as follows: viscosity 220 mPa·s, surface tension 52 mN / m, yarn stiffness after impregnation up to 5.07 cm, and tensile strength up to 0.44 N / tex. Example

[0025] This embodiment provides a method for preparing a konjac glucomannan-modified pea starch glass fiber impregnating agent, the method comprising the following steps: (1) Add water to pea starch and gelatinize it at 85°C for 30 minutes to obtain a pea starch solution with a mass percentage concentration of 12%; (2) Dissolve konjac glucomannan in water at 60°C by stirring, and prepare a konjac glucomannan solution with a mass percentage concentration of 2%. Steps (3) and (4) are the same as in Example 1.

[0026] The glass fiber sizing agent prepared in Example 2 was subjected to performance testing. The test results were as follows: viscosity was 250 mPa·s, surface tension was 50.5 mN / m, yarn stiffness after impregnation reached 5.13 cm, and tensile strength reached 0.47 N / tex. The mechanical properties of the yarn were better than those of the sizing agent in Example 1.

[0027] Comparative Example This comparative example uses pure pea starch to prepare a glass fiber sizing agent. The specific steps are as follows: Pea starch was gelatinized with water at 85°C for 30 minutes to obtain a pea starch solution with a mass percentage concentration of 10%. Add 4% glycerol, 1.5% vegetable wax and 0.8% choline dihydrogen phosphate to a pea starch solution, and then homogenize at high speed to obtain a glass fiber sizing agent.

[0028] The glass fiber sizing agent prepared in the comparative example has a loose film formation, a high yarn breakage rate, and a tensile strength of only 0.28 N / tex.

[0029] In summary, based on the performance test results of the sizing agents in Examples 1 and 2 and the comparative examples, it can be seen that modifying pea starch with konjac glucomannan improves the film-forming performance of the pea starch glass fiber sizing agent.

[0030] The embodiments described above are merely illustrative of implementation methods of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A method for preparing a konjac glucomannan-modified pea starch glass fiber impregnating agent, characterized in that, The method includes the following steps: S100: Pea starch is gelatinized with water at 85°C for 30 minutes to obtain a pea starch solution; S200: Konjac glucomannan is dissolved in water at 60°C by stirring to obtain konjac glucomannan solution; S300: Mix pea starch solution and konjac glucomannan solution at a mass ratio of 4:1, add silane coupling agent, and carry out esterification grafting reaction at 75°C for 1 hour to obtain a mixed solution; S400: Plasticizer, lubricant and antistatic agent are added to the mixture, and the mixture is homogenized at high speed to obtain the wetting agent.

2. The preparation method of the konjac glucomannan-modified pea starch glass fiber impregnating agent according to claim 1, characterized in that, The pea starch solution in S100 has a mass percentage concentration of 8-12%.

3. The preparation method of the konjac glucomannan-modified pea starch glass fiber impregnating agent according to claim 1, characterized in that, The mass percentage concentration of the konjac glucomannan solution described in S200 is 1~2%.

4. The preparation method of the konjac glucomannan-modified pea starch glass fiber impregnating agent according to claim 1, characterized in that, The silane coupling agent described in S300 is γ-aminopropyltriethoxysilane, and its addition amount is 0.5~1% of the total mass of pea starch solution and konjac glucomannan solution.

5. The preparation method of the konjac glucomannan-modified pea starch glass fiber impregnating agent according to claim 1, characterized in that, The plasticizer described in S400 is glycerin, and its addition amount is 3-5% of the mass of the mixture.

6. The preparation method of the konjac glucomannan-modified pea starch glass fiber impregnating agent according to claim 1, characterized in that, The lubricant described in S400 is a plant wax, and its addition amount is 1 to 2% of the mass of the mixture.

7. The preparation method of the konjac glucomannan-modified pea starch glass fiber impregnating agent according to claim 1, characterized in that, The antistatic agent described in S400 is choline dihydrogen phosphate, and its addition amount is 0.5~1% of the mass of the mixture.

8. A glass fiber impregnating agent, characterized in that, It is prepared by the method of preparing konjac glucomannan-modified pea starch glass fiber impregnating agent according to any one of claims 1-7.

9. The glass fiber impregnating agent according to claim 8, characterized in that, The glass fiber impregnating agent has a solid content of 12-15% and a viscosity of 150-300 mPa·s.

10. An application of a glass fiber impregnating agent, characterized in that, The glass fiber sizing agent according to claim 8 or 9 is applied in the field of glass fiber furnace drawing or textile processing.