We have so far unsuccessfully used graphite powder to make our own stretchy conductive glue or paint. But it is possible to make non-stretch glue/paint by mixing graphite powder and liquid tape together.
>> http://www.instructables.com/id/Make-Conductive-Glue-and-Glue-a-Circuit/
Suppliers
>> Local lock smiths
5 Comments so far
Don’t bother with graphite powder to make conductive materials. Chopped carbon fiber is MUCH better.
You can also use video or audio tape. The resistance per length is pretty accurate.
I have tried to mix glue and graphite powder to get some kind of pressure-sensitive mini-cushions but it doesn’t work (I have tried silicon glue).
i also tried this, unsuccessfully. but it would be so nice if we could get it to work!
>> http://web.media.mit.edu/~plusea/?p=1496
Researching drug up a study of proportions for graphite & acetylene black proportions.The results should be applicable to other carriers than the one studied.
“Studies on graphite based conductive paint coatings” S. Syed Azim∗, A. Satheesh, K.K. Ramu, S. Ramu, G. Venkatachari
Conclusions were that the optimum conductive pigment load was 85% graphite and 15% acetylene black and that the other non volatile components (e.g. the original carrier paint) was 30%.
The acetylene black bridges the gap between graphite particles.
“The optimized composition having the minimum resistivity in the range of 2 × 10−5 OHM with volume solids (Vs) 40%, and pigment volume concentration (PVC) 55%. In the pigment content the graphite occupies the major portion of 85%, and remaining portion is carbon black so as to reduce the resistivity of the paint further.”
“2.1. Materials
The binder used in the present work was, a poly sulphide modified epoxy resin having 100% solids. It was cured with a polyethylene polyamine, diluted to application consistency with measured quantities of mixed solvents (iso-propyl alcohol:methyl iso-butyl ketone:Cellosolve).
The graphite filler used was lamellar structured graphite. Its carbon content is 98–99%, typical particle size is up to 50 um and its density is 2.26 g/cc (SD fine chemicals). Volumetric oil absorption was determined according to ASTM D 285–94 and was found to be 0.4ml oil to ml of graphite, i.e. 40%. The graphite used was a conductive grade. Carbon black used was a commercial one.”
Sources for acetylene black seem to be hard to find in small quantities, despite wide industrial use. Sources anyone?