Soft–Hard Segment Combined Carbonized Polymer Dots for Flexible Optical Film with Superhigh Surface Hardness

Abstract

The rapid development of optical and electronic devices has driven up the demand of high performance optical protective films to avoid exterior influence and extend the service life. But it is not easy to obtain an ideal coating film with high transmittance, high hardness, and good flexibility. Herein, by taking advantage of the special core−shell structure of carbonized polymer dots (CPDs), we propose a strategy to build up a nanoscale soft−hard segment microstructure for optical protective coating materials. The CPDs with hard core and soft polymer chain shell are prepared from citric acid and (3-aminopropyl)triethoxysilane. The as-prepared CPDs can be converted directly to the coating film by the dehydration and cross-linking. In addition to the good optical transmittance, the final film exhibits simultaneously ultrahigh 9H pencil hardness to stand 4000 cycles of a steel-wool wear test, and excellent flexibility to stand bending and rolling-up.

Flexible Transparent Hydrophobic Coating Films with Excellent Scratch Resistance Using Si-Doped Carbonized Polymer Dots as Building Blocks

“…In addition, its critical inward and outward bending diameter could reach 1 mm (Figure I). As shown in Figure , results of some recent studies ,,,,,, and our work on flexible protective coating are plotted in Ashby maps to visualize material properties.…”

Carbon Dots Based Photoinduced Reactions: Advances and Perspective

“…developed the CPDs with hard core and soft polymer chain shell which prepared from CA and (3‐aminopropyl)‐triethoxysilane, directly employed in optical coating film with high transmittance, high hardness, and good flexibility. [ 47 ]…”

“…[46] According to the special core-shell microstructure of CPDs, Pan et al developed the CPDs with hard core and soft polymer chain shell which prepared from CA and (3-aminopropyl)triethoxysilane, directly employed in optical coating film with high transmittance, high hardness, and good flexibility. [47] Besides the above nonmetal elements doping in CDs, introducing metal ions or constructing metal-carbon bond can also bring surprising properties optimization. Metal-doped CDs are mainly derived from organometallic complexes or metallic salts compounding with carbon precursors under one-step hydrother-mal or pyrolysis.…”

CVD Deposited Epoxy Copolymers as Protective Coatings for Optical Surfaces

“…In the literature, a variety of polymeric materials such as poly(methyl methacrylate) [ 5 ], poly(carbonate) [ 6 , 7 ], poly(styrene) [ 8 ], poly(urethane) [ 9 ], poly(ethylene terephthalate), poly(ethylene naphthalate) [ 10 ], benzocyclobutene [ 11 ], perfluorovinyl ether cyclopolymer (CY-TOP) [ 12 ], tetrafluoroethylene and perfluorovinyl ether copolymer (Teflon AF) [ 13 ], fluorinated poly(arylene ether sulfide) [ 14 ], and fluorinated hyperbranched polymers [ 15 ] were investigated as coatings on optical surfaces. Most of these studies suggest that homopolymer films do not exhibit thermal and mechanical strength required for the protection of optical surfaces on their own [ 16 , 17 , 18 ]. To overcome this issue, crosslinking and combining polymeric materials [ 18 , 19 , 20 , 21 ] or modifying the polymer surface with inorganic coatings to improve thermal, mechanical and optical properties and adhesion between the coating and the substrate [ 16 , 17 , 22 ] have been evaluated.…”

“…Most of these studies suggest that homopolymer films do not exhibit thermal and mechanical strength required for the protection of optical surfaces on their own [ 16 , 17 , 18 ]. To overcome this issue, crosslinking and combining polymeric materials [ 18 , 19 , 20 , 21 ] or modifying the polymer surface with inorganic coatings to improve thermal, mechanical and optical properties and adhesion between the coating and the substrate [ 16 , 17 , 22 ] have been evaluated. Zhao et al fabricated liquid-release polymeric gel films with a novel bilayer structure which consist of a slippery liquid-locked rough top layer and liquid-supplied bottom layer by one-pot casting [ 19 ].…”