nylon 35% Latamid turning to dust

[dom253]

Does anybody have any experiences of glass filled nylon turning to dust. The application is a compressed air filter. The housing is aluminium, and the GFN component is fitted within the housing. It see's compressed air condensate, probably in the 7-16 barg pressure range, at anything upto 80 Degrees C. The condensate enters the filter as a vapour, and the GFN internals separate the water vapour from the compressed air. The GFN components have been decomposing so much that they can be crumbled between your fingers. I have had the condensate analysed for chlorides, sulphates, nitrates and any other cations and anions but the results were that there was nothing above 1ppm. The pH was 5.8. Am i missing something? What could be causing this damage.

 

[CoryPad]

Nylon does absorb water, and that could be exacerbated by the temperature.

Have you contacted Lati? They should be able to provide technical assistance.

If that isn't an option, then try a different polyamide supplier - DuPont, DSM, BASF.

 

[Compositepro]

You probably have large swings in the humidity in the line. This causes large stress as the nylon expands and contracts. This probably leads to loss of adhesion between the glass fibers and nylon which causes strength loss and accelerates absorption-desorption of water since it can now wick along the glass fiber surfaces. This is a mechanical degradation process, not chemical.

 

[dom253]

that sounds interesting CompositePro. The only thing is that i have never seen this before and these components are subjected to constant humidity & pressure differentials. However, this problem seems to happen in only one installation type (oil free compressors), i wonder if the temperature and humidity levels created by these compressors differ to a standard installaton type. I'll look into this more, thanks for the help compositepro