Method for preparing polymer anti-counterfeiting film based on nanocellulose photonic crystal fragments
A technology of nanocellulose and photonic crystals, applied in the field of biomaterials, can solve the problems of anti-counterfeiting technology of nanocellulose photonic crystal film, affecting the formation of liquid crystal pitch and poor mechanical properties of nanocellulose cholesteric liquid crystal structure, and achieving bile The effect of steroidal liquid crystal texture pattern is clear, the size is balanced, and good mechanical properties
Image
Examples
preparation example Construction
[0028] A method for preparing a polymer anti-counterfeiting film based on nanocellulose photonic crystal fragments, the preparation method of the anti-counterfeiting film includes the following steps:
[0029] Preparation of S1 nanocellulose suspension: add cellulose into concentrated sulfuric acid with heating and stirring for acidolysis, add 10 times the volume of concentrated sulfuric acid in deionized water to stop the reaction, centrifuge the solution to remove the supernatant, and centrifuge the lower sediment Wash, repeat several times, carry out dialysis after ultrasonication, concentrate, and put the nanocellulose suspension after ultrasonication in a few days and place it in the refrigeration layer of the refrigerator for standby use;
[0030] S2: Dilute the nanocellulose suspension obtained in the above steps to 0.2-4%, and perform ultrasonic treatment on the diluted nanocellulose dispersion for 15-30min;
[0031] S3 get an appropriate amount of the above-mentioned ...
Embodiment 1
[0040] Add microcrystalline cellulose into concentrated sulfuric acid with heating and stirring for acidolysis, add deionized water with 10 times the volume of acid to terminate the reaction, centrifuge the solution to remove the supernatant, and centrifuge and wash the lower layer of the precipitate. Dialysis was carried out, the suspension was ultrasonically treated after a few days, the nanocellulose suspension obtained in the above steps was diluted to a mass concentration of about 1%, and 20 ml of the diluted nanocellulose dispersion was ultrasonically treated for 2 hours. Drying method After drying for 5-7 days, complete drying in a vacuum oven at 40° C. for 24h-48h to obtain an iridescent nanocellulose photonic crystal film with cholesteric liquid crystal properties. Then, the nanocellulose film is placed in a tetrahydrofuran solution, and the nanocellulose photonic crystal iridescent film fragments are obtained after homogenization for 15-30 minutes. The actual size is...
Embodiment 2
[0042] The type of material used, the amount and the technological process are the same as those in Example 1, the difference is that after obtaining the photonic crystal film of iridescent nanocellulose with cholesteric liquid crystal properties, the above film is placed in a tetrahydrofuran solution, and the nanocellulose is obtained after ultrasonication for 15-30min. Cellulose photonic crystal iridescent membrane fragments. The actual size is 20-150μm×20-150μm, and its thickness is 20-70μm.
PUM
| Property | Measurement | Unit |
|---|---|---|
| Thickness | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
- IPC
- C08J5/18; C08L1/04
- CPC
- C08J5/18; C08J2301/04
- Inventors
- 张振; 常天