I would like to know if there is a supplier of raw materials for low
quantity molding of chloroprene (neoprene), and what is the necessary
equipement. I am specifically interested if there is a simple process
in a similar way like with urethanes:
http://www.devcon.com/devconfamilyproduct.cfm?familyid=151.0&catid=14

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Clarification of Question by iuliu76-ga on 23 Dec 2004 19:47 PST

Nitrile (Buna-N) rubber is also ok..

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Request for Question Clarification by redhoss-ga on 24 Dec 2004 11:55 PST

I am familiar with pourable urethanes and casting resins of different
types. I am also familiar with compression molding neoprene. When I
first read your question I thought that compression molding was the
only process for molding neoprene and I still think that I may be
somewhat right. I can't find any process for molding neoprene that
doesn't involve heat and pressure. I doubt that there is any type of
"pourable" neoprene (for your sake I hope that I am wrong). What
properties are you looking for in your product. Is it possible that
some other elastomer might work as well as neoprene. One other
thought, compression molding is not a very difficult process. Would
you be interested in information on compression molding of neoprene.

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Clarification of Question by iuliu76-ga on 24 Dec 2004 14:20 PST

I am trying to make connections between electrical cables that will
last well underwater. Essentially two cables are connected
electrically and the entire connection, including some overlap with
the jacket of the cables will be casted into some rubber that needs to
bond very well to the jacket of the cable (PVC or neoprene) and to the
metal parts. I have tried Urethane, but it did not bond too well
neither to PVC nor to the metal parts - essentially you could pull
them easilly out of the connection + the urethane itself was not very
rubbery - more like an elastic plastic, which did not suit me.

So yes, I would be interested in a different elastomer, as long as it
bonds well with metal and PVC or Neoprene, has elasticity similar to
neoprene, resists to water well and can be cured into a simple mold,
use limited resources (say 500$) plus some pointer to some company
willing to sell prototype amounts of raw materials.

An equally good answer will be a link to a clear description of
methods and equipment to cure neoprene or Buna-N together with some
pointer for small quantity supplies of raw materials

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Request for Question Clarification by redhoss-ga on 24 Dec 2004 14:42 PST

Have you tried silicone. That would be my first choice.

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Clarification of Question by iuliu76-ga on 24 Dec 2004 19:40 PST

I did not investigate/try silicone. I was concerned about it's strengh
(I might use the same process for molding some watertight connectors).
I don't know anything about it's water resistance.

Hello iuliu76, I think that silicone is the answer to your problem. I
have used RTV silicone before and it is a very good product for your
application. Here is some good information:

http://www.mgchemicals.com/products/silicones/appguide/electrical_app.html

RTV162 White, one part, high strength, low odor, non-corrosive neutral
cure, electronic grade silicone adhesive sealant. Meets Mil spec
requirements and UL recognition.

http://www.rhenatech.com/edocs/6517.shtml

Product with good flow properties, low shrinkage, excellent tensile
and tearing strength. Used wherever high mechanical demands have to be
met, e. g. cable end terminals, connectors, moulds, etc.

This might be the best choice for "molding some watertight connectors".

http://www.gesilicones.com/silicones/getoshiba/business/answercenter/faq/rtv.shtml?SMSESSION=NO

I found some very interesting info on silicones on this page.

I believe this will be the solution for you, Redhoss