4results about How to "Flexible performance" patented technology

The invention provides an optical fiber sensor and a preparation method thereof and an optical fiber magnetic field sensing device.The optical fiber sensor comprises an optical fiber, a fixing part and a plurality of magnetic parts, the optical fiber is provided with a macro-bending section formed by bending, and the optical fiber is fixed through the fixing part so that the macro-bending section can be kept in a bending state; the plurality of magnetic members are respectively connected to the macro-bending section at intervals along the macro-bending section. When the optical fiber sensor is arranged in a magnetic field, the magnetic part is subjected to the action of the magnetic field, so that the macro-bending section is further bent and deformed, the macro-bending diameter and the effective refractive index difference correspondingly change, and spectrum drift is caused. The magnetic field intensity and the direction can be measured by representing the wavelength drift distance and the drift direction in the spectrum. The optical fiber sensor has the advantages of simple structure, flexible and adjustable performance, low cost, high stability and the like, and can realize accurate measurement of magnetic field intensity and direction in a complex environment.

The application discloses a kind of microporous polyimide anti-plasticizing gas separation membranes containing symmetric double benzimidazole and a preparation method thereof, belong to the technical field of polymer materials.The technical scheme includes that diamine monomer containing symmetric double benzimidazole group is dissolved in solvent, then acid anhydride monomer with porogenic element is added in batches, polyamic acid membrane is obtained by scraping after reaction, then imidization is carried out to obtain polyimide gas separation membrane containing symmetric double benzimidazole group.The application is applied to high-pressure or high-absorptive gas separation aspect, solves the problem that conventional polyimide gas separation membrane is easy to plasticize, can simultaneously improve gas separation performance and anti-plasticizing property.

The present invention discloses a guanidine polymer and its preparation method and use. The guanidine polymer has a structure of R-NH-a-R'; wherein a includes at least one structural unit shown in the general formula (A); R and R' are each independently selected from hydrogen, a structural unit having one or more of the structures shown in (Formula 21) to (Formula 25), and R and R' are not hydrogen at the same time. The preparation method of the guanidine polymer includes: selecting at least one guanidine salt having a structure shown in the general formula (3) and at least one double-terminal amino diamine having a structure shown in the general formula (4) for condensation polymerization; and then performing the end-capping reaction with an end-capping agent. The guanidine polymer of the present invention has high end-capping reaction efficiency during the synthesis process and can be carried out under mild conditions; the production and product safety are both high, and the product quality of the grafted polymer produced subsequently is improved.