Crystallographic deformation in mechanically soft colloidal crystals derived from polymeric latex dispersions

Men, Yongfeng

doi:10.1039/c2sm25335f

Cited by 5 publications

(3 citation statements)

References 38 publications

(68 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After being applied to a substrate, a three-step strategy was used by this glue to accomplish adhesive activity at the interface, including (i) tight packing of the particles upon evaporation, (ii) deformation of the particles toward intimate interactions, and (iii) coalescence (cross-linking) between adjacent particles to create a cohesively strong solid (76)(77)(78)(79). Analogously, these engineered synthetic nanoparticles boost the mechanical interlocking of the glue at the interface in a pattern similar to that of the spheroidal nanoparticles observed in the ivy-derived adhesive, as documented in the previous reports (39,40,75,80,81). In this respect, in contrast to the consecutive molecular events in which the AGP-rich ivy nanoparticles are involved as detailed above, it is logical to propose here that these two types of polymeric nanoparticles share considerable mutual principles underlying their respective adhesive activities.…”

Section: Bioinspired Engineering Application Of the Adhesion Mechanismssupporting

confidence: 53%

Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

Huang

Wang

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Over 130 y have passed since Charles Darwin first discovered that the adventitious roots of English ivy (Hedera helix) exude a yellowish mucilage that promotes the capacity of this plant to climb vertical surfaces. Unfortunately, little progress has been made in elucidating the adhesion mechanisms underlying this high-strength adhesive. In the previous studies, spherical nanoparticles were observed in the viscous exudate. Here we show that these nanoparticles are predominantly composed of arabinogalactan proteins (AGPs), a superfamily of hydroxyproline-rich glycoproteins present in the extracellular spaces of plant cells. The spheroidal shape of the AGP-rich ivy nanoparticles results in a low viscosity of the ivy adhesive, and thus a favorable wetting behavior on the surface of substrates. Meanwhile, calciumdriven electrostatic interactions among carboxyl groups of the AGPs and the pectic acids give rise to the cross-linking of the exuded adhesive substances, favor subsequent curing (hardening) via formation of an adhesive film, and eventually promote the generation of mechanical interlocking between the adventitious roots of English ivy and the surface of substrates. Inspired by these molecular events, a reconstructed ivy-mimetic adhesive composite was developed by integrating purified AGP-rich ivy nanoparticles with pectic polysaccharides and calcium ions. Information gained from the subsequent tensile tests, in turn, substantiated the proposed adhesion mechanisms underlying the ivy-derived adhesive. Given that AGPs and pectic polysaccharides are also observed in bioadhesives exuded by other climbing plants, the adhesion mechanisms revealed by English ivy may forward the progress toward understanding the general principles underlying diverse botanic adhesives.ivy nanoparticle | ivy adhesive | arabinogalactan protein | adhesion mechanism | reconstructed adhesive A lthough there is a growing interest in exploring mechanisms regulating a variety of adhesive behaviors in the animal kingdom (1-6), the molecular basis allowing creeping plants, such as English ivy (Hedera helix), to generate sufficient adhesive force, aiding in clinging to vertical surfaces, is rarely discussed (Fig. 1A). Previous studies have emphasized mechanical strategies exploited by multiple climbing organs that evolve in plants (7-11). Nevertheless, the role of the glue-like viscous exudates that are observed on the majority of these organs and that cement the plants to the substrates has been less explored (10,12,13). Diverse polysaccharides and glycoproteins, comprising mucilaginous pectins, arabinogalactans, arabinogalactan proteins (AGPs), and many others, have been identified to be the predominant components in these adhesive substances (14-17); however, the molecular mechanisms underlying the high-strength adhesion remain elusive.By means of atomic force microscopy (AFM), bulk spherical organic nanoparticles have been observed in the exudates derived from the root hairs of English ivy (18-20). These proteinaceous nanoparticles are presum...

show abstract

Section: Bioinspired Engineering Application Of the Adhesion Mechanismssupporting

confidence: 53%

Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

Huang

Wang

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…case, the process of drying yields latex particles packed into a colloidal crystalline structure (Men, 2012). Taking advantage of the scatterless slit systems, we measured the sample under different beam sizes.…”

Section: Figurementioning

confidence: 99%

Achieving grazing-incidence ultra-small-angle X-ray scattering in a laboratory setup

Zheng

et al. 2015

J Appl Cryst

Self Cite

View full text Add to dashboard Cite

A grazing‐incidence sample stage was designed for realizing grazing‐incidence scattering measurements, especially in the ultra‐small‐angle regime, in a modified Xenocs Xeuss system in the laboratory. The designed sample stage, which is composed of four separate motorized positioning stages, allows the sample to be moved along four different directions to locate it in the proper position for scattering measurement. In an effort to realize grazing‐incidence ultra‐small‐angle scattering (GIUSAXS) measurements, both the separation of the collimation slit systems and the sample‐to‐detector distance have been lengthened. At a separation of the collimation slit systems of 2400 mm and a sample‐to‐detector distance of 6558 mm, the effective smallest scattering vector magnitude qmin reaches 0.01 nm−1. A colloidal crystalline thin film obtained from drying a polystyrene latex dispersion on silicon substrate was measured in the setup in GIUSAXS mode at different beam sizes. The resultant GIUSAXS patterns at smaller beam sizes reveal fine crystalline structures in the film.

show abstract

“…Latex dispersions made of polymeric particles with a typical size of around 100 nm have attracted much attention over the past decades because of their applications in paints, paper coatings and water-based adhesives. [1][2][3][4][5] They are also considered to be excellent model systems for studying the crystallization behavior of atoms and molecules because their typical size and timescales are easily accessible experimentally by using many techniques, such as microscopy and scattering techniques. [6][7][8][9][10] Drying of latex droplets on a solid surface is a frequently used method to fabricate various ordered structures, [11][12][13] and has been extensively studied by many researchers using various techniques, including optical microscopy, 14,15 analytical balance, [16][17][18] reflectance spectroscopy 19,20 and grazing incidence small angle X-ray scattering (GISAXS).…”

Section: Introductionmentioning

confidence: 99%

Buckling-induced structural transition during the drying of a polymeric latex droplet on a solid surface

Chen

Boyko²,

Rieger³

et al. 2012

Soft Matter

Self Cite

View full text Add to dashboard Cite

Crystallographic deformation in mechanically soft colloidal crystals derived from polymeric latex dispersions

Cited by 5 publications

References 38 publications

Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

Achieving grazing-incidence ultra-small-angle X-ray scattering in a laboratory setup

Buckling-induced structural transition during the drying of a polymeric latex droplet on a solid surface

Contact Info

Product

Resources

About