Self-cleaning adhesive

Use of nanotubes have been reported by Ge et al. (2007) in enhancing adhesion by gecko-inspired adhesion in production of carbon nanotube-based synthetic gecko tapes, and by Sethi et al. (2008) in the production of gecko-inspired carbon nanotube-based self-cleaning adhesives. More information about nanocomposite adhesives can be found in O Chap. 55. 

Bhushan B, Jung YC (2011) Natural and biomimetic artificial surfaces for superhydro-phobicity, self-cleaning, low adhesion, and drag reduction. Prog Mater Sci 56 1-108... 

The Lotus Effect simulates the properties of the lotus flower in nature, by microstructured hydrophobic protrusions which enable surfaces to clean themselves by water in motion. By making use of innovative technologies, the Lotus Effect can be used on many different products. For example, self-cleaning surfaces could be used for self-adhesive films, injection moulded parts or painted components in the construction industry, for facade elements or window frames, for traffic facilities such as road signs, and not to forget cars themselves. 

In the first step of a lamination process, a foil or film is produced. This is then laminated onto the fabric, either by heat and pressure or by means of an adhesive. The laminated foil places considerable constraints on the flexibility of the fabric but offers better protection than a coating and is self-cleaning. 

The top-coats are responsible for the durability and resistance to water and chemical impacts from the environment. Mainly acrylic and fiuori-nated polymers are used for top-coats on various base coats (PVC, PUR, PTFE, silicone rubber, etc.) to enhance resistance to soiling and ageing. Certain additives for UV protection can be added. Due to its self-cleaning non-adhesive surface the top-coat is often hard and brittle. On PVC coatings the top-coat gives not only protection against environmental infiuences but also a barrier against emission of plasticizer out of the PVC. 

Mimicking the robust dry adhesion displayed by geckos is of interest to materials research for military, consumer, and biomedical applications. Recently, seven key characteristics of gecko adhesion were identified by Autumn (1) directional (or anisotropic) adhesion, (2) robust attachment with minimal mechmical preload, (3) easy detachment, (4) promiscuous adhesion, (5) self-cleaning, (6) non-self-adherent, and (7)... 

We must note that the property of tackiness is used to trap dust particles in self-cleaning oil filters, in coarse dust filters for motor vehicles, in Rank filters made of metal screen, and on the precipitation plates in konimeters, impactors, and other such devices. Moreover, adhesion to a tacky base may be used in investigating dust content and dust compositions, particularly in trapping dust in the ground layer of the atmosphere. 

Figure 16.3 SLIPS and organogel materials with self-cleaning properties. (A) The originally reported SLIPS material that not only exhibits low adhesion to water and oil, hut also shows low adhesion to ice formed on its surface. (Reprinted hy permission from Macmillan Publishers Ltd Nature, Cop Tight (2011)). (B) A silicone-oil suffused organogel that can be used to self-clean with water. (Adapted from ref. 16 with permission from John Whey and Sons. Cop right 2013 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim.)...

Besides self-cleaning, the application of hydrogels can also be extended to other areas such as capture and regulation of oil drops underwater. The key question is to realize hydrogels with stimulus-responsive adhesion properties. Chen et al. reported that a poly(N-isopropylactylamide) (PNIPAAm) hydrogel exhibited a wettability and underwater oil adhesion switch... 

M. Osman, R. Rasool, and R. A. Sauer, Computational aspects of self-cleaning surface mechanisms, in Advances in Contact Angle, Wettability and Adhesion, Vol.l, K.L. Mittal (Ed.), pp. 109-130, Wiley-Scrivener, Beverly, MA (2013). 

In view of the absence of published data regarding the mechanism underlying the behavior of a tacky layer in the capture of dust, we must at present confine attention to qualitative considerations. It should be noted that the property of tackiness is used for the trapping of dust particles in self-cleaning oil filters, rou -cleaning automobile antidust filters. Rank filters made of metallic mesh, settling plates in konimeters, impactors, and similar apparatus [162]. In addition to this, adhesion to... 

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