CN-117983146-B - Graphene-PBAT composite aerogel and preparation method thereof

Abstract

The application provides graphene-PBAT composite aerogel and a preparation method thereof, which belong to the technical field of biodegradable materials and aerogel, and comprise the following steps of preparing graphene oxide dispersion liquid; adding an amphoteric surfactant into graphene oxide dispersion liquid, stirring uniformly, filtering, washing, freeze-drying to obtain modified graphene oxide, using 1, 4-dioxane as a solvent, completely dissolving PBAT in the 1, 4-dioxane to obtain a PBAT solution, adding the modified graphene oxide into the PBAT solution, dispersing uniformly by ultrasonic, performing liquid phase compounding, adding deionized water after the liquid phase compounding is completed, stirring uniformly, pouring into a mould, pre-freezing treatment, and freeze-drying. The composite aerogel has the characteristics of high specific surface area, large porosity, small density and the like, the mechanical property of PBAT is enhanced by the composite of the modified graphene, the problems of low PBAT strength, poor weather resistance and low modulus are solved, and the finally obtained composite aerogel has wider application range.

Inventors

• BAI YONGXIAO
• LI GUOHAO

Assignees

• 兰州大学

Dates

Publication Date

20260505

Application Date

20240111

Claims (10)

1. 1. The preparation method of the graphene-PBAT composite aerogel is characterized by comprising the following steps of: s1, preparing graphene oxide dispersion liquid; s2, adding an amphoteric surfactant into the graphene oxide dispersion liquid, uniformly stirring, and performing suction filtration, washing and freeze drying to obtain modified graphene oxide; s3, using 1, 4-dioxane as a solvent, and completely dissolving PBAT in the 1, 4-dioxane to obtain a PBAT solution; S4, adding the modified graphene oxide into the PBAT solution, uniformly dispersing by ultrasonic waves, and carrying out liquid phase compounding; And S5, adding deionized water after the liquid phase compounding is completed, pouring into a mold after uniformly stirring, pre-freezing, and then freeze-drying to obtain the graphene-PBAT composite aerogel.
2. 2. The method for preparing the graphene-PBAT composite aerogel according to claim 1, wherein the amphoteric surfactant is one or more of lauramidopropyl amine oxide, cocamidopropyl amine oxide, stearamidopropyl amine oxide, OAE-18 and OAE-14.
3. 3. The method for preparing graphene-PBAT composite aerogel according to claim 1, wherein in the step S4, the mass ratio of the modified graphene oxide to the PBAT is 1-3:100.
4. 4. The method for preparing the graphene-PBAT composite aerogel according to claim 1, wherein the weight percentage of the PBAT in the PBAT solution is 6-8wt%.
5. 5. The method for preparing the graphene-PBAT composite aerogel according to claim 1, wherein in the step S4, the weight content percentage of the modified graphene oxide is 0.14-0.18 wt%.
6. 6. The method for preparing the graphene-PBAT composite aerogel according to claim 1, wherein the temperature of the liquid phase composite is 40-50 ℃.
7. 7. The preparation method of the graphene-PBAT composite aerogel according to claim 1, wherein the pre-freezing treatment temperature is-10 to-20 ℃ and the treatment time is 12-24 hours.
8. 8. The preparation method of the graphene-PBAT composite aerogel according to claim 1, wherein the freeze-drying temperature is-40 to-50 ℃, the vacuum degree is 1-10 Pa, and the time is 24-36 h.
9. 9. The method for preparing a graphene-PBAT composite aerogel according to any one of claims 1 to 8, wherein the graphene oxide dispersion is prepared by modifying the Hummers method.
10. 10. A graphene-PBAT composite aerogel, characterized in that it is obtained by the preparation method according to any one of claims 1 to 9.

Description

Graphene-PBAT composite aerogel and preparation method thereof Technical Field The application belongs to the technical field of biodegradable materials and aerogel, and particularly relates to graphene-PBAT composite aerogel and a preparation method thereof. Background Aerogel is a nanoscale porous solid material formed by replacing liquid phase in gel with gas in a certain drying mode through a sol-gel method, and has the characteristics of high porosity (> 90%), low density, high specific surface area and the like. The aerogel material has excellent heat insulation performance due to the characteristics, and has excellent performances in various aspects such as photoelectrocatalysis, adsorption separation, heat insulation and heat preservation. With the development of different types of gel synthesis and drying technologies, the variety of aerogel materials is more and more abundant, and the aerogel materials are widely applied in the fields of thermal, optical, acoustic, electrical, adsorption catalysis and the like. However, the research on aerogel mainly has problems that firstly, most of aerogel materials have complicated preparation process and high cost, and secondly, many aerogels are non-degradable materials, which brings great trouble to subsequent waste material treatment and causes secondary pollution to the environment. Patent CN114085418a discloses a degradable high-hydrophobic aerogel porous material and a preparation method thereof, wherein the degradable aerogel is prepared by mainly combining left-handed polylactic acid and right-handed polylactic acid. However, polylactic acid materials are large in brittleness and poor in elongation at break and toughness, so that the mechanical properties of aerogel materials prepared by the polylactic acid materials are limited, and meanwhile, toxic reagents such as trichloromethane are used in the whole preparation process, so that the environment is endangered during waste liquid treatment. Patent CN116102766A discloses an ultra-light high flame-retardant biodegradable PLA foam and a preparation process thereof, wherein RDP, lignin, APP and silica aerogel are compounded to obtain a flame-retardant system, and then are mixed with PLA, PBAT and an epoxy chain extender for supercritical foaming to prepare a foam material. The preparation process comprises a plurality of systems and more substances, the reaction is more complex, and the interface interaction between different substances is difficult to control. Polyadipic acid/butylene terephthalate (PBAT) is a synthetic aliphatic-aromatic copolyester that degrades completely within a few weeks under the action of enzymes naturally present in fertile soil. The PBAT has the biodegradability of the aliphatic polyester and the good mechanical properties of the aromatic polyester, has good ductility, elongation at break, heat resistance and impact property, and also has good biodegradability, and is one of the best degradable materials which are very active in the current biodegradable plastic research and applied to the market. But PBAT has the problems of poor crystallinity, low melt strength, high price and the like, and limits the application of the PBAT in more fields. Therefore, the PBAT needs to be modified and enhanced to a certain extent, so as to achieve the purpose of improving the comprehensive performance of the PBAT. Graphene has excellent mechanical strength, conductivity, high specific surface area and high thermal stability, and the polymer nanocomposite of the graphene often shows remarkable performance improvement at a lower addition amount. The graphene material is used as a functional material to modify the PBAT, so that the mechanical property of the PBAT can be effectively improved, and the functional application of the PBAT is realized. However, the common graphene oxide is hydrophilic and oleophobic, and cannot be uniformly dispersed in common organic reagents, so that liquid phase compounding with PBAT cannot be performed, and further graphene composite biodegradable material aerogel cannot be prepared. Disclosure of Invention The application aims to provide graphene-PBAT composite aerogel and a preparation method thereof, so as to improve the strength, weather resistance and modulus of PBAT materials. In order to achieve the above object, according to a first aspect of the present application, there is provided a method for preparing graphene-PBAT composite aerogel, which comprises the steps of firstly performing rapid modification on graphene oxide by using an environment-friendly amphoteric surfactant, rapidly finishing the surface modification on graphene oxide by hydrogen bonding and electrostatic interaction by the amphoteric surfactant, losing hydrophilicity of the modified graphene oxide to obtain excellent lipophilicity, providing necessary conditions for subsequent liquid phase compounding, then selecting a relatively environment-friendly 1, 4-dioxane as a solvent, perfo