Mimicking the Wettability of the Rose Petal using Self-assembly of Waterborne Polymer Particles

Abstract

In this work we present a novel platform to synthesize polymeric "raspberry" particles and explore their use to fabricate surfaces with low wettability and high water adhesion, resembling the properties of naturally occurring surfaces such as the rose petal. The raspberry particles were obtained by layer-by-layer self-assembly of 850 nm core polystyrene particles bearing surface carboxylate groups and corona nanoparticles of different sizes and polymers (polystyrene, poly(para-fluorostyrene) or poly(2,3,4,5,6-penta-fluorostyrene), also bearing surface carboxylates), interleaved with positively charged poly(ally amine) hydrochloride. The raspberry particles were then bound together by covalent coupling of the carboxylate groups with the amine groups of the polymeric interlayer. The films produced by dropcasting the raspberry particles exhibited static water contact angles between ~135º and ~146º, depending on the nature of the corona, hysteresis of ~135º and high adhesion of water droplets. Since all particles were synthesized from scratch by surfactant free emulsion polymerization in air and every step of the protocol was performed in water, this platform is up-scalable and environmentally friendly.

Dual Stimuli-Responsive Phenylboronic Acid-Containing Framboidal Nanoparticles by One-Step Aqueous Dispersion Polymerization

“…Polymeric framboidal particles have attracted attention in many research area including biomimetic science, 18 surface chemistry, 19 and photonic science. 20 So far, several methods have been developed to engineer such polymeric structures.…”

Hierarchical ZnO particles grafting by fluorocarbon polymer derivative: Preparation and superhydrophobic behavior

“…6(B) even shows a hexagon form because of more ordered nanorods distribution for ZnO-6. Many recent reports exhibit hierarchical superhydrophobic particles possessing spherical secondary dimensions [5,8,12,[14][15][16]32] or highly fractal topology [17][18][19]36], different from nanorods in this work. No matter what morphology is formed by these particles, however, the analysis and explanation of their superhydrophobic behavior are in agreement, which could be attributed to low-wettable chemical composition and high surface roughness.…”

“…One widely adopted way seems to be assembling microand nanoscale particles with a functional group as a connection, which could be carried out via various methods, including condensation of functional groups [5][6][7][8], supermolecular self-assembly [9] and layer-by-layer assembly [10][11][12]. Another beneficial synthesis route is realized by the growth of nanoscale structure from microscale substrate, of which the in situ polymerization to grow polymer nanophase [13,14] and sol-gel process forming silica colloidal particles around existing cores [15][16][17][18][19] are mostly noticed.…”

Fabrication of fluorinated raspberry particles and their use as building blocks for the construction of superhydrophobic films to mimic the wettabilities from lotus leaves to rose petals

“…Examples of such applications include the transport of liquid micro droplets over a surface without sliding or rolling, 39 micro sample tissue engineering and biological analysis, 44 microfluidic chips, 44 "mechanical hands" 45 and so on. 16,28,32,47,48 In 2012, Wang et al developed a strategy for the fabrication of superhydrophobic coatings with strong adhesion to water from RPs with a submicron SiO 2 core that was decorated by nano-sized polystyrene latex particles via γ-ray radiation-induced miniemulsion polymerization of styrene in the presence of 3-methacryloxypropyltrimethoxysilane (MPS)-functionalized SiO 2 particles. 16,46 Raspberry-like particles have shown great applications in the fabrication of superhydrophobic surfaces due to their inherent dual-size hierarchical structures and surface roughness.…”

“…13 While silica-based, polymer/ inorganic hybrid, or polymeric RPs have been extensively employed to prepare superhydrophobic films to mimic the surfaces of lotus leaves during the past decade, reports on the use of RPs to mimic the 'rose petal effect' have only appeared since 2012. 28 Almost at the same time, Liu et al presented an approach for the preparation of a superhydrophobic film with strong adhesion to water from RPs via the seeded dispersion polymerization of styrene in the presence of seed particles obtained from the dispersion polymerization of hydrolyzed-MPS and styrene. 16,28,32,47,48 In 2012, Wang et al developed a strategy for the fabrication of superhydrophobic coatings with strong adhesion to water from RPs with a submicron SiO 2 core that was decorated by nano-sized polystyrene latex particles via γ-ray radiation-induced miniemulsion polymerization of styrene in the presence of 3-methacryloxypropyltrimethoxysilane (MPS)-functionalized SiO 2 particles.…”