5
$\begingroup$

I want to apply tire rubber on surfaces, for various reasons - including protection against water. I think of tire rubber, as it is so widely available - helping in reducing pollution (infinitesimally) at the same time.

I am interested in a solvent which will temporarily transform the tire rubber into a (viscous) liquid - in such way that after some time, when the solvent evaporates, the tire rubber becomes solid again.

I do not need any special properties of the new rubber, there will be nothing really safety critical. If it is similar enough to the original, it is good.

Ideally, the solvent should be easy to find and I should be able to buy it without any special permits.

Think of this:

  • there are some granules of salt;
  • I add some water - and get salty water;
  • after some time the water evaporates and I get 1 block of salt.

Now, the salt is actually pieces of tire rubber, and the water is... what? :)

I searched on the net, and the only solvent I recognized was acetone. Does anyone have any experience with this?

Improve this question
$\endgroup$
5
  • 2
    $\begingroup$ Carbon disulphide is used to dissolve rubber but it will not be easy to buy nor will it be easy to work with unless you have a laboratory. I appreciate that this doesn't answer your question but it will give you an idea of the difficulties you will encounter. $\endgroup$
    – DarrenRhodes
    May 16, 2019 at 9:52
  • $\begingroup$ :) Thank you for the heads up. I had a good feeling about it - being a difficult task. Of course, if you will find a way to make the difficulties less impacting, I will be happy. $\endgroup$
    – virolino
    May 16, 2019 at 10:08
  • $\begingroup$ I think chloroalkanes would do the job though I don't have supporting info. Dichloromethane (aka methylene chloride) is the lightest and evaporates quickly. Chloroform and carbon tetrachloride are more toxic. $\endgroup$
    – SteffX
    May 16, 2019 at 14:59
  • 2
    $\begingroup$ The environmentally friendly way to do this is shred or grind the tires to suitable sized particles and then mix them with a bonding material. No hazardous chemicals required, but you can't do it easily yourself. It is already done on a commercial scale (the product is called "crumb rubber") so disposing of your tire at a recycling site is just as good for the environment as doing something yourself. $\endgroup$
    – alephzero
    May 16, 2019 at 16:12
  • 4
    $\begingroup$ Tire rubber is a crosslinked polymer. Doesn't really melt or dissolve as far as I know (depends on the degree of crosslinking). Crosslinked polymers can swell, but you might have trouble finding a solvent that fits your water/salt analogy. pslc.ws/macrog/xlink.htm $\endgroup$
    – mcole
    May 16, 2019 at 20:14

2 Answers 2

Reset to default
6
$\begingroup$

As it was mentioned in the comments, finished rubber is a cross-linked polymer, and this is the main reason why getting vulcanized rubber liquefied without destroying it seems to be a nearly impossible task. Also, there might be other additives, e.g. tires are most likely going to contain powdered charcoal, so that even though one can dissolve the rubber by destroying the cross-linking $\ce{(-S-S-)_n}$ bonds, charcoal is likely going to form another phase, and who knows what might happen to other additives during this process. Finally, at the end you have to somehow recreate cross-linking for the rubber to retain it's elasticity, and this doesn't happen on its own by just evaporating the solvent (see vulcanisation).

In general, the majority or rubber types can be affected by:

  • strong oxidizing agents (to the extreme of being irreversibly destroyed);
  • aromatic and chlorinated hydrocarbons (both have a tendency to soften rubber). Visually it appears as if rubber is swelling; this can happen if one keeps rubber in chloroform or xylene for an extended period of time – for instance, this property is sometimes used to fit rubber tubing in place.

What I suggest is to use a so-called rubber mix or rubber compound: a semi-finished mix of [natural] rubbers, vulcanizing agents, plasticizers, fillers and additives (carbon, chalk, kaolinite etc.). Rubber mix is used ubiquitously in the industry to produce all sorts of rubber products, including composite materials such as rubberized fabric. Rubber mix is a versatile material which is highly viscous at the room temperature, but softens upon heating to approx. 100 °C and can be dissolved in volatile organic solvents (even benzene and gasoline). The drawback is that at the end you still have to use vulcanization to crosslink the rubber.

Improve this answer
$\endgroup$
0
2
$\begingroup$

I know this is old but I stumbled across it because I was intrigued by a question on a game show. I found a patent from the 30s that has some interesting information related to your question. In fact, it almost seems like the guy was doing exactly what you are trying to do. As others have pointed out, it’s definitely not a process I would want to try at home, but it is definitely an interesting read!

https://patents.google.com/patent/US2019207A/en

Improve this answer
$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.