fouling (thing)

Many major engineering problems are caused when an unwanted substance or organism sticks to something. A major area of Materials Science research deals with the development of novel anti-fouling surface coatings.

Mussels and barnacles will attach themselves to almost anything, even Teflon or Paraffin wax. If enough fouling organisms attach themselves to a marine structure like an oil drilling rig or a pier, they can cause enough drag to make that structure collapse during severe weather. Heavily fouled ships may loose as much as forty percent of their fuel efficiency.

The prevalent solution to prevent or reduce marine fouling is the use of anti-fouling paints containing the biocide, tributyl tin. Due the environmental damage that they cause, these paints have recently been outlawed and are not to be used from 2003 on.

Some organisms like coral and amphibians do not allow most fouling organisms to stick to them. They serve as an inspiration for biomimetic materials which may one day be mass produced and used as an antifoulant.

Layers of teflon that peel off as fouling organisims accumulate, electrical shock devices, and porous ceramic coatings filled with silicone oil are just some of the many approaches that have been tested.

The build up of cells and other material on medical implants like catheters, heart valve implants, or vascular stents can cause thrombosis, which can be fatal. Dealing with this kind of fouling is especially tricky because the antifoulants must not be toxic.

A polyethylene glyclol coating, when anchored to a metal surface with the adhesive mussel byssus protein Mefp-1, will almost completely prevent the adhesion of fibroblasts.

Microbes can be used to produce biosurfactant coatings.

Heparin coatings on vasscular stents have been used to prevent thrombosis.

When a gun is fired repeatedly, the barrel and other parts tend to gum up due to the buildup of residue from the gunpowder. Sometimes the powder residue is corrosive, which may exacerbate the problem.

The main solution to this problem is to clean all firearms regularly with something like hoppes #9. Some ammunition contains powder which is less corrosive than others.