Need advice regarding artificial rubber.

[janeriksen]

Which kind of artificial rubber with high tear and abrasive resistant should I go for in order to produce items with similar properties to shoe soles and tires with a hardness over shore A-80?

It needs also to have good bonding properties to metals.

 

[unclesyd]

With what little information provided I would go with a Polyurethane Elastomer the ones provided by Advanced Urethane Solutions.

http://www.urethane.net/

 

[janeriksen]

I was interested in liquid polymers for my own production. I looked at the urethane.net-site and understood that they only provide finished molded products.

I need to get some good polymers from somebody who sell these in bottles. Any suggestion about any good web dealers?

 

[MadMango]

Not sure exactly what you are looking for, but for prototypes and things of that nature I have had really good luck with

http://www.reynoldsam.com/

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of these Forums?

 

[ornerynorsk]

Urethane, both RTV and heat vulcanized, can be had from any good industrial supply house. It's a fairly involved process, equipment-wise, but simple enough in concept. With the heat vulcanized liquids, your final mechanical props are sensitive to air entrainment and humidity, so a good bell jar and vacuum pump are almost a must. Ten years ago I was going to be my own supplier of a "simple" urethane snubber. Gave it up because the vacuum equipment must be very high draw, mine produced something in the order of 26 to 27 inches, and it wasn't enough to dessicate and de-aerate the mixture quickly enough. I could never achieve advertised properties of the cured material.

There are multitudes of companies who do this at the professional level, reasonably priced, with consistent and repeatable results.

If you have a very high volume part, then you can justify going it to it on a grand scale.

Good luck.

 

[btrueblood]

I'd avoid urethane, just because to me it seems too slippery for a shoe sole (though you don't say exactly what your application is). It can be a good choice, but has some limitations for "outdoor" use. Urethane can be attractive because (like silicones) you can find room-temperature curable versions of the stuff. As ornerynorsk points out, the RTV compounds generally don't perform as well as high-temperature cured, molded rubber compounds.

Nitrile rubbers have higher tear strengths than urethanes (in general) and good abrasion resistance. They hold up better to a wider range of environments also. There are about a gazillion choices of "artificial rubber" compounds to choose from, and we've suggested two. SBR rubber is a common tire compound. EPDM can be compounded to be quite hard, and is very stable chemically. Butyl rubber can be made quite hard, and has the best impermeability to gases. Silicones...don't get very hard.

Any heat-cured rubber will bond well to metals, provided that you do your homework and find the appropriate bonding primers for the particular metal and rubber combination. One of the best ways to learn about rubber is to go visit a rubber molding shop and ask questions.

 

[tom1953]

FWIW, this might be a better topic for the Rubber Engineering forum (

http://eng-tips.com/threadminder.cfm?pid=335).

btrueblood, my experience (and quite a few references I've seen) is that urethanes generally have higher tear strength than nitrile rubber, and not all urethanes are "too slippery for a shoe sole". Castable (liquid) urethanes are generally slipperier than millable (rubber) urethanes. Urethanes are used today in footwear and shoe soling.