A method for improving the binding capacity of silica to polycaffeic acid

Abstract

The present application relates to a kind of method for improving the combination ability of silica and polycaffeic acid, belong to the technical field of textile printing and dyeing.The present application relates to the following process: (1) take the appropriate amount of silicon dioxide in deionized water, after dispersion, add polydienes dimethyl ammonium chloride, the mass concentration of two respectively is 0.5% and 0.1%, 50 ℃ keeps warm 30 min, centrifugal, washing, and obtain pretreated silicon dioxide;(2) pretreated silicon dioxide is added to deionized water, add caffeic acid, the mass concentration of two respectively is 0.5% and 0.4%, after ultrasonic mixing, add sodium periodate, and the molar ratio of sodium periodate and caffeic acid is 1:2, 60 ℃ reaction 3 h, centrifugal, washing, and obtain silicon dioxide and polycaffeic acid complex.The test shows that the method of the present application can make polycaffeic acid and silica more effective combination, form thicker coating and make particle size increase, and can give textile stronger light heat capacity.

Description

Technical Field

[0001] This invention relates to a method for improving the bonding ability between silica and polycaffeic acid, belonging to the field of textile printing and dyeing technology. Background Technology

[0002] Caffeic acid is found in natural plants such as coffee beans, apples, and honeysuckle, and possesses advantages such as antioxidant, anti-inflammatory, and preservative properties, making it widely used in food, medical, and cosmetic fields. However, monomeric caffeic acid suffers from poor stability and easy oxidation. Polycaffeic acid prepared through oxidative polymerization not only retains the excellent physicochemical properties of bulk caffeic acid but also exhibits stronger structural stability and adhesion properties, showing broad application potential in material surface modification and functional modification. Common methods for preparing polycaffeic acid include free radical polymerization, enzyme-catalyzed polymerization, and chemical oxidative polymerization. The products obtained by different methods vary in terms of degree of polymerization and physicochemical properties.

[0003] Silica is a common inorganic compound with stable chemical properties, widely used in semiconductors, papermaking, textiles, medicine, optics, and other fields. In recent years, researchers have attempted to combine silica with polymers possessing catechol structures, such as polycaffeic acid, to produce composites with rich structures and strong adhesive properties, demonstrating excellent application value in the eco-friendly finishing of textiles. Typically, the combination of silica and polycaffeic acid occurs in a dispersion containing silica particles. Strengthening the interaction between the two to improve their binding ability is key to forming more effective composites. Summary of the Invention

[0004] This invention utilizes polydimethylammonium chloride to pretreat silica to alter its surface properties. Then, caffeic acid and sodium periodate, an oxidant, are added to its dispersion to initiate a polymerization reaction that generates polycaffeic acid. This process enhances the bonding ability between silica and polycaffeic acid, resulting in a more effective composite and improved treatment effects on textiles.

[0005] This invention relates to the following processes: (1) Take an appropriate amount of silica and place it in deionized water. After dispersing, add polydimethylammonium chloride. The mass concentrations of the two are 0.5% and 0.1%, respectively. Keep warm at 50℃ for 30 min, centrifuge, and wash with water to obtain pretreated silica. (2) Add pretreated silica to deionized water and add caffeic acid. The mass concentrations of the two are 0.5% and 0.4%, respectively. After ultrasonic mixing, add sodium periodate with a molar ratio of 1:2 to caffeic acid. React at 60℃ for 3 h, centrifuge and wash with water to obtain silica-polycaffeic acid complex.

[0006] An appropriate amount of silica was placed in deionized water and ultrasonically dispersed. Polydiallyldimethylammonium chloride (PDMC) was then added, with mass concentrations of 0.5% and 0.1%, respectively. The mixture was kept at 50°C for 30 min, centrifuged, and washed with water to obtain pretreated silica. The silica used was a commercially available, conventional product, and the PDMC was a commercially available product with a molecular weight of 400,000-500,000. In this process, PDMC effectively binds to silica through electrostatic and van der Waals forces, altering its surface structure, charge, and affinity / repulsion properties, which enhances its subsequent binding with polycaffeic acid.

[0007] Pretreated silica was added to deionized water, along with caffeic acid at mass concentrations of 0.5% and 0.4%, respectively. After ultrasonic mixing, sodium periodate was added at a molar ratio of 1:2 to caffeic acid. The mixture was reacted at 60°C for 3 hours, followed by centrifugation and washing with water to obtain a silica-polycaffeic acid complex. During this process, caffeic acid and pretreated silica bond more effectively and are oxidized and polymerized to form polycaffeic acid, resulting in the silica-polycaffeic acid complex. Detailed Implementation

[0008] The invention is further illustrated by examples and comparative examples.

[0009] Example 1 (1) Take an appropriate amount of silica and place it in deionized water. After dispersing, add polydimethylammonium chloride. The mass concentrations of the two are 0.5% and 0.1%, respectively. Keep warm at 50℃ for 30 min, centrifuge, and wash with water to obtain pretreated silica. (2) Add pretreated silica to deionized water and add caffeic acid. The mass concentrations of the two are 0.5% and 0.4%, respectively. After ultrasonic mixing, add sodium periodate with a molar ratio of 1:2 to caffeic acid. React at 60℃ for 3 h, centrifuge and wash with water to obtain silica-polycaffeic acid complex.

[0010] Comparative Example 1 Untreated silica was added to deionized water, and caffeic acid was added at mass concentrations of 0.5% and 0.4%, respectively. After ultrasonic mixing, sodium periodate was added at a molar ratio of 1:2 to caffeic acid. The mixture was reacted at 60°C for 3 h, centrifuged, and washed with water to obtain a silica-polycaffeic acid complex.

[0011] The particle size of the silica-polycaffeic acid composites obtained in Example 1 and Comparative Example 1 was tested, and the results were 935.9 nm and 330.7 nm, respectively. This indicates that the method of the present invention enables polycaffeic acid and silica to combine more effectively, forming a thicker coating and increasing the particle size.

[0012] The silica-polycaffeic acid composites obtained in Example 1 and Comparative Example 1 were prepared into dispersions of the same concentration and deposited onto pure cotton fabrics under the same conditions. After irradiation under the same light conditions, their surface temperatures rose to 54.7°C and 43.1°C, respectively. Under the same conditions, the surface temperature of the cotton fabric without the silica-polycaffeic acid composite only rose to 31.4°C. This is due to the efficient light absorption of polycaffeic acid, which converts light energy into heat energy. It can be seen that because the silica in the composite obtained in Example 1 binds more polycaffeic acid, the treatment effect on the cotton fabric is enhanced, allowing its surface temperature to rise to a higher level.

Claims

1. A method for improving the bonding ability between silica and polycaffeic acid, characterized in that... The following process is adopted: (1) Take an appropriate amount of silica and place it in deionized water. After dispersing, add polydimethylammonium chloride. The mass concentrations of the two are 0.5% and 0.1%, respectively. Keep warm at 50℃ for 30 min, centrifuge, and wash with water to obtain pretreated silica. (2) Add pretreated silica to deionized water and add caffeic acid. The mass concentrations of the two are 0.5% and 0.4%, respectively. After ultrasonic mixing, add sodium periodate with a molar ratio of 1:2 to caffeic acid. React at 60℃ for 3 h, centrifuge and wash with water to obtain silica-polycaffeic acid complex.