[stickstick]

Hello,
I was wondering what material is used on the palms of american football gloves used by receivers. They are usually marketed as having some sort of trademarked material but what sort of thing would it be comprised of? I was thinking nitrile or latex but any other ideas? In other words what soft rubbers can be made which are very sticky or tacky but wont tear easily and is flexible?
Many thanks in advance

[wildfyr]

FTIR could give you a hint but anything more than what you've guessed is a trade secret worth a heck of a lot of money

[Enthalpy]

"Won't tear easily" suggests a polyurethane. It offers a high coefficient of friction too.
"Flexible" is nearly no constraint. Elastomers can be made stiff or flexible almost at will.

Chemical analysis will tell the family of the elastomers (or the mix, this is common practice), but many subtleties change the properties of polymers and are less easy to analyse: the degree of cross-linking, crystallinity, and so on.

[stickstick]

Thanks for the replies. Could anyone point me in the right direction for a laymans guide to mixing different rubbers. I really know nothing about it and just learning.

[P]

Thanks for the replies. Could anyone point me in the right direction for a laymans guide to mixing different rubbers. I really know nothing about it and just learning.

Do you really mean 'mixing rubbers'  or do you mean blending or making co-polymers?  Some rubbers are blended by folding them over and over at temperature, sort of masticating them together until they are mixed... then you cool it. Rubber is a polymer....  and there are so many types of polymers that you can alter or adjust through blends or chemical co-polymerisations and adjustments.

I don't want to sound dismissive of your question, but you could literally write books about the subject  -  so, and I hate suggesting this usually but, have you tried typing 'mixing rubber' into google?  It will come up with 1000s of hits....  your eye can scan through all of the wide range of varied results and maybe pick out something that is relevant to what you are looking for.

I mean  -  what is it that you want to know?

[stickstick]

Hi P,
Yep been doing alot of research but as you have probably guessed im completely new to all this and just learning. Basically I have had a business product idea that I want to try and do

What I want to do is to be able to blend certain rubbers together in liquid form to make a material which would be durable and tacky when set with a very low shore hardness. I was intially thinking of latex however there are the obvious issues with allergies to it.

So, for example is it possible to blend polyurethane with say nitrile in a liquid form? What would the result of that be?

[P]

So, for example is it possible to blend polyurethane with say nitrile in a liquid form? What would the result of that be?

I am not sure if the 2 will just blend.  If they could be dissolved, mixed, then reprecipitated out together or something that might work (not sure what dissolved nitrile stuff though). Or if you take the temperature up to a level where they can be masticated together mechanically then that could work..  then there is the possibility of starting from the monomerics and trying to make a co-polymer....  I am probably showing my ignorance to experts here as I do not know if you can do any of this with the polymers involved. Enthalpy and Wilfyr, who commented above, are both polymer people and might know more.

Also  -  what is common when blending 2 polymers together in an attempt to get the best properties of both is that you usually end up with the worst properties of both without the benefits of either!  lol. 


If you just wanted to make the rubber you have tackier then maybe the addition of a small amount of solvent or oil into the rubber might soften it.   Is this for the glove coating idea or do you have another application for the sticky rubber? What about a polyester?

[wildfyr]

A notable property of polymers is that unless contently bound they are generally immiscible with one another over the long term. Look up the term "macrophase separation." Even block copolymers which are covalently bound to one another will under go microphase separation, where they form separate domains on the microscale (and give some really amazing AFM images!).

The important thing I am trying to convey is that its very hard to blend polymers together in a way where the mechanical properties won't degrade due to phase separation behavior. This is an intrinsic property of polymers.

[Enthalpy]

Natural rubber: in some compositions used for medicine and gloves, the allergenic proteins are removed. But don't expect a good resistance to sunlight and ozone pollution from pure natural rubber.

Blend in liquid form: probably not. Most elastomers can't be molten, as they deteriorate instead. Mixing the reactants prior to polymerisation is sometimes possible and done to obtain a copolymer. [Sorry for introducing the wrong term "mix"].

Nitrile makes known copolymers with butadiene and some more, it's rather common among elastomers. Never heard about copolymers with polyurethane, but there are so many rubbers and I know few ones.

My general impressions:
- Thousands of elastomer formulations already exist, you just need to find the existing one fitting your purpose.
- Some companies specialise in selling the proper elastomer (which they don't manufacture). They would tell you which one you need, and what makes the gloves just by touching and sniffing it.
- Producing elastomers is nothing for newcomers. Even making a "blend" (as sellers call it, being it a mixture or a copolymer) looks badly difficult and can be deadly.
- But you might create a company that buys individual elastomers and sells them in a wide catalogue with adequate help for choice. It needs to acquire usage knowledge, not manufacturing skills. I was happy to buy from such companies in the past, even at 100* the kg price, just to have their advice and small amounts. While chemists often know what elastomer they want, mechanical engineers don't.