Trikoot

We all love rubber as a material, but at least for me, some of the less favourable features of rubber includes its strong friction against anything and everything, without suitable lubrication. This results in rubber clothing being occasionally difficult to put on, and uncomfortable to wear if the lube wears out. Also, excessive friction increases the tendency of rubber to tear.

Chlorination of rubber, which is the exposure of the surface of rubber to chlorine gas, aims to solve this problem. Chlorine, while interacting with rubber, changes the surface structure of rubber, reducing its friction.

This change can be dramatic: when I chlorinated a rubber catsuit I could not put on even with lubrication, after chlorination it slid on without any lubrication whatsoever.

While some rubber vendors have already started to offer chlorination as a service, it is extremely easy and cheap to do it home. I have chlorinated several pieces of my wardrobe, including a full catsuit, without any problems, and I am in the process of chlorinating my entire rubber collection.

WARNING: Chlorine gas is toxic and corrosive to lungs. Never do chlorination indoors, even in ventilated areas. Chlorine gas is heavier than air and will remain in areas, and possibly travel downwards in a building ventilation system. ALWAYS DO CHLORINATION OUTDOORS WHILE WEARING NECESSARY PROTECTION.

What do you need for chlorination?

• Plastic bucket, between 10 and 20 litres
• Warm water
• A gas mask with activated carbon filter (this includes most modern gas masks filters)
• Rubber gloves
• Household bleach with approximately 5 percent sodium hypochlorite (check the label)
• White vinegar (10% acetic acid). Skip the high-end cooking stuff and get the most industrial looking bottle you can find.

Preparing rubber for chlorination

Before treating the rubber, it must be completely clean of all dirt, stains, grease and lubrication. Especially silicone is notoriously difficult to remove, but I have found dishwashing liquid to be a great help. Parts of the rubber covered by stains or lube will not be treated and will remain sticky after chlorination.

Chlorination process

1. Fill plastic bucket 75% full of warm water.
2. Insert garment to be treated
3. Insert 400 millilitres of white vinegar and stir briefly
4. Wear your gas mask
5. Insert 300 millilitres of household bleach, and stir immediately for 60 seconds. You will notice the surface appearance of the garment change immediately. Do not expect bubbling or a dramatic chemical reaction.
6. Rinse the garment under clean, cold water and leave to air dry.

If you want to repeat the process, you can use the processing liquid again by adding again 400 millilitres of white vinegar and 300 millilitres of household bleach.

For chemistry nerds

When sodium hypochlorite (NaOCl) is mixed with acetic acid (CH3COOH), the first main reaction is an acid–base step in which hypochlorite is protonated to form hypochlorous acid (HOCl) and sodium acetate:

NaOCl + CH3COOH <=> HOCl + CH3COONa.

If sufficiently acidic conditions are present and a source of chloride ions is available, a second reaction can occur in which hypochlorous acid reacts to form chlorine gas:

HOCl + H+ + Cl => Cl2 + H2O.

So, chlorine gas is not produced directly by acetic acid alone; it arises only after hypochlorite is first converted to hypochlorous acid and the necessary acidic, chloride-containing conditions are met.

Simple molarity-based stoichiometric calculations are not sufficient in chlorination of latex, because the reaction outcome depends strongly on pH, not just mole ratios. The first step (conversion of OCl to HOCl) is an acid–base equilibrium that only proceeds significantly when enough acid is present to lower the pH. The subsequent formation of chlorine gas requires not only hypochlorous acid but also sufficiently acidic conditions and available chloride ions. Therefore, it’s practical to have an excess of acetic acid in the solution at all times.

Other things to note

• Chlorination will only occur when rubber is in direct contact with the gas being formed in the liquid.
• Most of the time a garment needs to be treated twice, turning it inside out between treatments.
• Multiple treatments do not harm rubber. If the process fails, the surface simply remains unchanged.