Effect of crystallinity on surface morphology and light transmittance of poly(vinylidene fluoride‐co‐hexafluoropropylene) thin film

Abstract

Homopolymer of vinylidene fluoride and its copolymers containing hexafluoropropylene (HFP) were prepared from free radical solution polymerizations and spin-coated on the glass slides to fabricate thin film with a thickness of $ 1 lm. It was found that the surface morphology of fluorinated thin films was strongly dependent on the crystallinity of polymers. In addition, the surface morphology was the most important factor to determine the optical transmittance of glass coated with the fluoropolymer thin film. As decreasing the crystallinity of the polymer by introducing HFP with a bulky CF 3 moiety, the surface of thin film became flattened and the transmittance of visible light was increased by reducing scattering.

Engineering crystalline quasi-two-dimensional polyaniline thin film with enhanced electrical and chemiresistive sensing performances

“…Nevertheless, ~90% of transmittance can still be observed on the q2D PANI after 7 days of reaction (~30 nm thick) which can be attributed to the excellent chain ordering that reduces light scattering (Fig. 3a) 42 . By increasing the HCl concentration of water subphase from 0.02 to 1 M, we can identify a monotonic rise in the absorbance at 360 nm (π–π* transition of the benzenoid ring) and above 600 nm (free-carrier absorption) (Fig.…”

Vapor-based synthesis and micropatterning of Janus thin films with distinct surface wettability and mechanical robustness

“…Fluorinated polymers tend to introduce optical hazes due to crystallization and phase segregation of the uorochemical components, which usually results in poor light transmittance. 31,36 The optical transparency of the Janus lm can be attributed to the ultrathin thickness of the uorinated layer and the lower degree of uorinated aggregates compared with that in reported iCVD PPFDA lms. 28 The ability to produce micropatterns on free-standing Janus lms opens up opportunities for applications such as miniature devices and transdermal drug delivery.…”

Cyanostilbene‐Based AIEgen Smart Film: Optical Switching by Engineering Molecular Packing Structure and Molecular Conformation Through Thermal and Photoinduced Monotropic Phase Transition

“…This is a result of a kinetically controlled domain size. [ 62 ] As shown in the inset images of Figure 3a, the domain size of the slowly cooled D4CS film is approximately 10–100 µm. However, the quenched film exhibits definitely much smaller domains, resulting in severe light scattering.…”