Fluorinated polymers are a class of fascinating materials due to their unique features; however, they have not been applied widely in daily life because of the restricted synthetic methodology and limited availability of various monomers. In this work, main-chain-type semifluorinated alternating terpolymers (SFATs) (AB1)n-co-(AB2)m are prepared by a step transfer-addition and radical-termination (START) polymerization strategy using NaI as the catalyst under irradiation with visible light at room temperature. Herein, 1,6-diiodoperfluorohexane and two α,ω-unconjugated dienes with different structures are used as A, B1 and B2 monomers, respectively. Interestingly, a dual alternating polymerization process can be possible at the beginning of terpolymerization by using dienes with flexible and rigid chains as B1 and B2, respectively. In addition, compared to binary copolymers (AB)n previously synthesized by START polymerization, facile regulation of Tg of the SFATs can be achieved easily either by adjusting the feed ratio of two B monomers or by the removal of the periodic iodine atoms formed in SFATs. Overall, this work provides a guide for the synthesis of a broad range of fluorinated polymers by increasing participating monomers, allowing easier adjustment of the chemical composition and facilitating the integration of desirable properties into fluoropolymers to fulfill diverse requirements in practical application.
Fluorinated substances are often introduced to enhance the hydrophobicity of surfaces of various materials. In this work, fluorinated macromolecular coupling agents (AB) n A- b -PIPMSA m are prepared via successive step transfer-addition and radical-termination (START) polymerization and photocontrolled iodine-mediated reversible deactivation radical polymerization (RDRP) at room temperature, which is then decorated on the surface of silica nanoparticles followed by iodine removal for preparing iodine-free macromolecular fluorinated silica nanoparticles (macro-F-SiNPs-I). Superhydrophobic coatings were produced simply by spin coating of the macro-F-SiNPs-I onto glass or dip coating on cotton substrates. The effect of a variety of parameters on surface superhydrophobicity, such as the solvent for spinning coating, concentration of macro-F-SiNPs-I, size of silica nanoparticles and chemical structures of (AB) n A- b -PIPMSA m , were studied in detail, and the superhydrophobic surfaces with water contact angle (WCA = 172.6°) could be facilely achieved under optimum conditions. In addition, the resultant macro-F-SiNPs-I coatings are quite stable against acidic (pH = 1), basic (pH = 13) or high salty solutions, and their excellent superhydrophobic performance was also confirmed by self-cleaning and oil/water separation experiments, which displayed fascinating promise in practical applications on a large scale.
危险品化学品经营许可证（带存储）