Preparation method and application of functional wax gourd biomass aerogel

Abstract

The invention discloses a preparation method and application of functional white gourd biomass aerogel, the white gourd biomass aerogel is prepared by using the characteristics of large size of white gourd and hydrogel structure and adopting a simple and mild dehydration pore-forming technology, and good biological characteristics are reserved; the white gourd biomass aerogel is subjected to antibacterial modification or hydrophobic modification, the functional white gourd biomass aerogel is obtained, and the functional white gourd biomass aerogel can be applied to the fields of preparation of hemostatic materials, liquid absorption materials, medicine carrying base materials, tissue scaffold materials, composite material base materials, hydrogel base materials, filtering materials, heat insulation and heat preservation materials and the like and has a huge potential application prospect.

Description

Technical Field

[0001] The invention belongs to biomass material processing technology, and specifically relates to a preparation method and application of functional wax gourd biomass aerogel. Background Art

[0002] As a new type of green and environmentally friendly porous material, biomass aerogel has unique advantages such as a wide range of raw material sources, green and non-toxic, good biocompatibility and biodegradability. These characteristics have made biomass aerogels widely concerned in the fields of energy, environment, electronics and biomedicine. The preparation of biomass aerogels usually involves key links such as raw material selection, activation treatment, and molding technology. The raw materials often select biomass resources, including agricultural waste (such as rice husks, wheat straw, corn cobs, etc.) and forestry waste (such as branches, bark, etc.), which are renewable and in line with the concept of green chemistry. For example, CN202410300158.4 discloses super-hydrophobic elastic aerogels constructed by waste biomass fibers and grapefruit peels, as well as their preparation and application, and uses silane reagents for hydrophobic modification to obtain super-hydrophobic elastic aerogels. CN202310489557.5 uses the extract of waste peels as a carbon source, obtains bacterial cellulose membranes by fermentation, and then obtains bacterial cellulose aerogels after directional freeze drying and chemical vapor modification. CN202311405571.9 discloses a biomass porous aerogel and its preparation method and application, wherein bagasse is carbonized and then compounded with MXene, and then freeze-dried to obtain an aerogel. At present, biomass aerogel mainly uses biomass raw materials as carbon sources, carbonizes them at high temperatures, and converts them into porous carbon materials. As mentioned above, waste resources often need to be crushed and then bonded, dried, and sintered into porous carbon materials. This type of aerogel has lost its biological characteristics and has a wide range of uses, but it also has many limitations.

[0003] To prepare biomass aerogels with biological properties, not only is it required that the raw materials come from biomass, but also that the preparation method can retain the biological properties of the aerogel. This requires the selection of raw materials. It is best that the biomass itself has larger individuals and good porosity, and the aerogel structure can be obtained in a gentle way during the preparation process. There are not many biomass resources that meet these requirements, and we need to change our thinking to discover and utilize it. Winter melon is a large vegetable, and its main body can be regarded as a hydrogel structure, which is an excellent biomass raw material for preparing aerogels. The present invention uses winter melon as a biomass raw material, prepares winter melon biomass aerogel through a gentle dehydration pore-forming technology, and performs functional modification on it to obtain a functional biomass aerogel with wide application value. Therefore, the technology of the present invention is an innovation to improve the utilization value of winter melon and expand its application field. Summary of the invention

[0004] The present invention aims to provide a preparation method and application of functional wax gourd biomass aerogel, which uses wax gourd as biomass raw material, utilizes the characteristics of its own hydrogel structure, and obtains biomass aerogel through simple and mild dehydration technology, and then performs functional modification based on the biomass aerogel to obtain biomass aerogel with antibacterial or hydrophobic properties, which can be widely used in the manufacture of hemostatic materials, liquid absorbing materials, tissue scaffold materials, filter materials, thermal insulation materials and other fields. In order to achieve the above purpose, the preparation method provided by the present invention comprises the following steps: S1. Remove the end, skin and pulp of the wax gourd, and cut it into slices of uniform thickness along the circumference; S2. Soak the winter melon slices obtained in S1 in baking soda water for a period of time and then remove and drain; S3. Soak the wax gourd slices obtained in S2 in an ethanol solution and then vacuum dry or steam dry, or supercritical fluid dry to obtain wax gourd biomass aerogel; S4. The wax gourd biomass aerogel obtained in S3 is subjected to antibacterial modification or hydrophobic modification to obtain a functional wax gourd biomass aerogel; the antibacterial modification is to introduce an antibacterial salt compound including one of silver salt, zinc salt, copper salt or magnesium salt into the aerogel; the hydrophobic modification is to introduce one of alkoxy, siloxane or ester groups into the aerogel through a grafting reaction.

[0005] Furthermore, the thickness of the wax gourd slices described in S1 is 1-20 mm.

[0006] Furthermore, the concentration of baking soda described in S2 is 0.1%~1%, and the soaking time is 1~600 min.

[0007] Furthermore, the ethanol content in the ethanol solution in S3 is 75% to 99%, and the glycerol content is 0.1% to 1%.

[0008] Furthermore, the soaking time of the ethanol solution in S3 is 12-72 h, and the vacuum drying or steam drying temperature is 50-80 °C.

[0009] Furthermore, the mass fraction of the antibacterial salt compound in S4 is 0.001%~0.1%. Preferably, the silver salt is silver nitrate, the zinc salt is zinc sulfate, the copper salt is copper sulfate, and the magnesium salt is magnesium chloride.

[0010] Furthermore, the alkoxy group in S4 is one of methoxy, ethoxy or propoxy, the siloxane group is one of methylsiloxane or fatty acylsiloxane, and the ester group is one of ethyl ester, propyl ester or fatty acid ester.

[0011] In addition, the present invention also provides a functional wax gourd biomass aerogel prepared by the above method.

[0012] Furthermore, the present invention also provides applications of functional wax gourd biomass aerogel, including use in manufacturing hemostatic materials, liquid absorbing materials, permeation absorbing materials, drug-carrying substrates, tissue scaffold materials, composite substrates, hydrogel substrates, filter materials, and thermal insulation materials.

[0013] The beneficial effects are: (1) By utilizing the hydrogel structural characteristics of wax gourd, the preparation method of biomass aerogel is greatly simplified and cost-effective. In addition, the prepared aerogel is a whole with good structural performance. (2) The preparation method of the present invention has mild conditions and retains the characteristics of wax gourd biomass. The obtained aerogel can be applied in the fields of biomedicine and health and hygiene. The material has good biocompatibility and is biodegradable, which meets the development requirements of green, low-carbon and environmentally friendly. DETAILED DESCRIPTION

[0014] The present invention is further described below in conjunction with specific embodiments. Example

[0015] The wax gourd was cut off from the end, peeled, and pulped, and cut into 10 mm thick wax gourd slices along the circumferential direction. The wax gourd slices were then soaked in a 1% baking soda solution for 300 min, and then removed and drained. The drained wax gourd slices were immersed in an 85% ethanol solution containing 0.5% glycerol for 48 h, and then the obtained wax gourd slices were moved into a vacuum drying oven and vacuum dried at 60 ° C for 12 h to obtain wax gourd biomass aerogel. The obtained aerogel was immersed in a 25 ppm silver nitrate solution and then vacuum dried to obtain wax gourd biomass aerogel with antibacterial function. Example

[0016] The wax gourd was cut off from the end, peeled and pulped, and cut into 1 mm thick wax gourd slices along the circumferential direction. The wax gourd slices were then soaked in a 0.1% baking soda solution for 1 min, and then removed and drained. The drained wax gourd slices were immersed in a 75% ethanol solution containing 0.1% glycerol for 12 h, and then the obtained wax gourd slices were sent to supercritical CO2 fluid drying to obtain wax gourd biomass aerogel. The obtained aerogel was immersed in a 2% methyltrimethylsiloxane acetone solution, and then vacuum dried at 50 ° C for 12 h to obtain the wax gourd biomass aerogel with hydrophobic function. Example

[0017] The wax gourd was cut off from the end, peeled and pulped, and cut into 20 mm thick wax gourd slices along the circumferential direction. The wax gourd slices were then soaked in a 0.5% baking soda solution for 600 min, and then removed and drained. The drained wax gourd slices were immersed in a 99% ethanol solution containing 1% glycerol for 72 h, and then the wax gourd slices were moved into a vacuum drying oven and steamed and dried at 80 ° C for 6 h to obtain wax gourd biomass aerogel. The obtained aerogel was immersed in a 100 ppm zinc sulfate solution and then vacuum dried to obtain wax gourd biomass aerogel with antibacterial function.

Claims

1. A method for preparing functional wax gourd biomass aerogel, characterized in that: The steps include: S1. Remove the end, skin and pulp of the wax gourd, and cut it into slices of uniform thickness along the circumference; S2. Soak the winter melon slices obtained in S1 in baking soda water for a period of time and then remove and drain; S3. Soak the wax gourd slices obtained in S2 in an ethanol solution and then vacuum dry or steam dry, or supercritical fluid dry to obtain wax gourd biomass aerogel; S4. The wax gourd biomass aerogel obtained in S3 is subjected to antibacterial modification or hydrophobic modification to obtain a functional wax gourd biomass aerogel; the antibacterial modification is to introduce an antibacterial salt compound including one of silver salt, zinc salt, copper salt or magnesium salt into the aerogel; the hydrophobic modification is to introduce one of alkoxy, siloxane or ester groups into the aerogel through a grafting reaction.

2. The method for preparing a functional wax gourd biomass aerogel according to claim 1, characterized in that: The thickness of the wax gourd slices described in S1 is 1-20 mm.

3. The method for preparing a functional wax gourd biomass aerogel according to claim 1, characterized in that: The baking soda concentration described in S2 is 0.1%~1%, and the soaking time is 1~600 min.

4. The method for preparing a functional wax gourd biomass aerogel according to claim 1, characterized in that: The ethanol content of the ethanol solution in S3 is 75% to 99%, and the glycerol content is 0.1% to 1%.

5. The method for preparing a functional wax gourd biomass aerogel according to claim 1, characterized in that: The soaking time of the ethanol solution in S3 is 12-72 h, and the vacuum drying or steam drying temperature is 50-80 °C.

6. The method for preparing a functional wax gourd biomass aerogel according to claim 1, characterized in that: The mass fraction of the antibacterial salt compound in S4 is 0.001%~0.1%. Preferably, the silver salt is silver nitrate, the zinc salt is zinc sulfate, the copper salt is copper sulfate, and the magnesium salt is magnesium chloride.

7. The method for preparing a functional wax gourd biomass aerogel according to claim 1, characterized in that: The alkoxy group in S4 is one of methoxy, ethoxy or propoxy, the siloxane group is one of methylsiloxane or fatty acylsiloxane, and the ester group is one of ethyl ester, propyl ester or fatty acid ester.

8. The functional wax gourd biomass aerogel obtained according to the preparation method of any one of claims 1 to 7.

9. The functional wax gourd biomass aerogel according to claim 8 is used to manufacture hemostatic materials, liquid absorbing materials, permeation absorbing materials, drug-carrying substrates, tissue scaffold materials, composite material substrates, hydrogel substrates, filter materials, and thermal insulation materials.