Design and synthesis of waterborne light-responsive cellulose nanocrystal/fluorinated polyacrylate films toward oil/water repellent and self-healing properties

Abstract

The development of environmentally friendly waterborne polymeric materials is becoming critical today.In this study, a kind of self-healing cellulose nanocrystal/ uorinated polyacrylate based on the reversible photo-induced dimerization of coumarin groups was prepared via RAFT-mediated Pickering emulsion polymerization using cellulose nanocrystal (CNC) particles modi ed with light-responsive amphiphilic copolymers as Pickering stabilizers. Emulsion polymerization and latex lm properties were signi cantly varied in dependence on the amount of 7-(2-methacryloyloxyethoxy)-4-methylcoumarin (CMA) monomer.Both the water and oil resistance and mechanical properties of the latex lm were dynamic in response to UV light. The maximum water contact angle and oil contact angle increased by 6.1° and 2.3°on the irradiation of UV light at 365 nm, respectively. The tensile strength of latex lm increased initially with increasing amount of CMA increased, from 0 up to 4 wt%, and then decreased. The maximum tensile value increased from 3.0 MPa to 6.4 MPa after the dimerization reaction activated by 365 nm UV light.Results from atomic force microscope (AFM) and energy dispersive X-ray spectrometer (EDX) revealed that latex lm possessed a roughness structure and the uorine had a remarkable enrichment on the lmair interface. Moreover, latex lms showed an excellent surface scratch self-healing ability owing to the reversible dimerization reaction of the coumarin groups, and the reversible dimerization reaction of coumarin groups within cellulose nanocrystal/ uorinated polyacrylate polymer was extensively investigated via ATR-FTIR spectrometer and differential scanning calorimetry (DSC). The fruitful outcomes indicated that light-responsive cellulose nanocrystal/ uorinated polyacrylate exhibited a greatly potential application as a smart material.

Self‐healing waterborne fluorinated polyurethane‐acrylate based on photoreversible reaction and hydrogen bonds

“…Methyl methacrylate (MMA) and butyl acrylate (BA) were supplied by Tianjin Kemiou Chemical Reagent Co. Ltd. Hexafluorobutyl acrylate (HFBA) was provided by Harbin Xuejia Fluorosilicide Co. Ltd. Before use, BA, MMA and HFBA were passed through basic aluminium oxide to remove the inhibitor. Poly(acrylic acid)‐ g ‐CNC‐ g ‐poly[(hexafluorobutyl acrylate)‐ co ‐7‐(2‐methacryloyloxyethoxy)‐4‐methylcoumarin] (MCNC) was prepared according to the process published by our research group 25 …”

“…[22][23][24] Therefore, by introducing fluorinated monomers into WPUA, it is expected that hydrophobic and oleophobic properties similar to those of fluorinated polymers can be obtained. Based on the previous research of our group, 25 selfhealing waterborne fluorinated polyurethane-acrylate (WFPUA) was obtained by Pickering emulsion polymerization of double bond-terminated polyurethane with acrylate and fluorinated monomers using modified cellulose nanocrystal (MCNC) as a stabilizer, and used for leather finishing. The chemical structures of WPUA and WFPUA were analyzed by Fourier transform infrared (FTIR) and 1 H NMR spectroscopic techniques.…”

“…Poly(acrylic acid)-g-CNC-g-poly[(hexafluorobutyl acrylate)-co-7-(2-methacryloyloxyethoxy)-4-methylcoumarin] (MCNC) was prepared according to the process published by our research group. 25…”

Biobased Composites from Eugenol- and Coumarin-Derived Methacrylic Latex and Hemp Nanocellulose: Cross-Linking via [2 + 2] Photocycloaddition and Barrier Properties

“…This reaction, known since the early 1900s, has in the last few decades been engineered in polymers to prepare light-responsive networks . Some works reported the photo-cross-linking of polymer latex particles exploiting coumarin functional groups, introduced by copolymerization or postpolymerization functionalization. , Self-healing photoresponsive cellulose nanocrystal-modified fluorinated polyacrylates containing coumarin derivatives were synthesized by Pickering emulsion polymerization. − In addition, a few examples of partially biobased photoresponsive polymer networks with coumarin functional groups have been reported. , However, to the best of our knowledge, coumarin-containing biobased polymer latexes photo-cross-linkable via [2 + 2] photocycloaddition have not been widely investigated so far.…”

Photo‐responsive cellulose nanocrystal modified fluorinated polyacrylate based on coumarin chemistry

“…In the recent study, our research group used poly(acrylic acid)-g-CNC-g-poly (hexafluorobutyl acrylateco-7-(2-methacryloyloxyethoxy)-4-methylcoumarin) PAA-g-CNC-g-P(HFBA-co-CMA) (MCNC) as a stabilizer to prepare a photo-responsive cellulose nanocrystal modified fluorinated polyacrylate emulsion by RAFT-mediated Pickering emulsion polymerization, and studied the effect of coumarin monomer dosage on the latex film properties. 32 In this work, we systematically investigated the effects of MCNC dosage on the emulsion polymerization, mechanical and self-healing properties of the latex films. In addition, the prepared photo-responsive cellulose nanocrystal modified fluorinated polyacrylate was used as a fabric finishing agent, and the hydrophobicity, oleophobicity and self-healing property of the finished fabric were studied.…”