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Etchant needed for etching Nylon-11

I am looking for an etchant for Rilsan (Nylon-11). I am needing to prepare the surface just as you would if you were going to apply another layer over it.

Johnathan Posey
Chemist Polymers - Clarksville, Arkansas, USA
2004

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Johnathan,

Why don't you get some corrosion charts on Nylons and just see which chemicals attack it. OK?

I'd assume that most aromatic hydrocarbons would but not, perhaps, polar solvents.

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2004

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I am not sure what you mean by "prepare the surface as you would if you were going to apply another layer over it." This leaves a multitude of option open to you. It is well known that nylons are pretty inert and not the easiest of polymers to coat with a metal layer (assuming you want metal). If it is metal the polymer needs etching and one patented way is to use "satinisation" as developed by DuPont. This involves dipping it in a mixture of 96.57% perchloroethylene, 0.3% (by weight) p-toluene sulphonic acid, 01.3% Cab-O-Sil and 3.0% dioxane. Leave it for 10 seconds at 121 °C and then remove it and put it in an oven at 121 °C for 20 seconds. Then rinse it in water at 75C and dry it. It can then be activated and initiated as if it were any other polymer. Alternatively you can use either formic acid and/or glacial acetic acid ⇦this on eBay or Amazon [affil links] as an etchant. There is another process where you open the nylon structure by soaking it in dilute sulfuric acid at room temperature and then etch it in a chromic oxide/sulfuric acid etch. However, be aware that nylons have a general tendency to suffer from a delayed action form any chemicals that may have been absorbed by it. This can cause all sorts of problems, even when you think you have done a good job. You can also etch nylons by plasma discharge or using a physical abrasive, but since you are quite sparse with details, I do not know if these will be applicable. Most nylons are not usually metallised because of their propensity to absorb moisture and lose dimensional stability, so perhaps you may want to rethink your ideas.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2004