Peroxide Cured Silicone and Possible Legislation

DCBP(Bis-2-4-Dichloro Benzoyl-Peroxide) is the peroxide of choice for HCR silicone users throughout the world for hot air vulcanisation. Over the last few years there have been problems from both supply and possible legislation.

Tragedy in China

During 2015 in the northern city of Tianjin (China) there was an explosion at a peroxide plant, this explosion caused the death of 50+ people. This horrific accident resulted in the shut down the port into the city for many months. Large numbers of manufactures in Europe were relying DCBP from this region and were no longer able to secure their supply. These manufacturers turned their attention to European supplied materials, which then caused huge supply issues throughout the industry. This event must be considered a major event for the silicone industry. Not only did it cause a problem for DCBP supply, but Chinese administration undertook an investigation to determine the causes of the explosion. This resulted in a major tightening to occurred regarding health and safety procedures, which lead to silicone manufactures in China having supply issues for the base materials. This domino effect led to next shock for the silicone industry, limited supply of silicone.

Time for change

China is changing every day and with the strength of the government it has there, it is able to make sweeping changes overnight. A key example of this is in regard to pollution. In particular silicone plants emitting high levels of toxic fumes which were being released into the atmosphere adding to the poor levels of air quality already seen there. These changes to acknowledge climate change and air quality caused massive shutdowns along the supply chain and not only have the Chinese government looked into pollution, they have also looked into the long term effects of the chemicals used in factories in China, including the effects on firefighters in the Tianjin explosion. There are rumours within the industry is that China is about to ban DCBP due to its long-term health implications, and any such ban is highly likely to spread worldwide. Within Europe silicone manufactures who cure silicone are facing increased scrutiny into the amounts they used and the end applications. This scrutiny is only likely to increase, and legislation is inevitable in the short term and bans long term.

 How to take action

Firstly, the biggest thing to remember about DCBP is FEAR. There is a fear from silicone manufactures that they will need to reformulate many formulations and they don’t have the formulation knowledge to do this. There is fear from product engineers that they cannot select a material that doesn’t pass the current legislation and they need the correct certification to prove this. To take away this fear prepare now for what the future may hold and get your formulations correct and begin processing small amounts of this material now so you gain the confidence for your new grade. DCBP should not be seen as a problem, but as opportunity. Manufacturers need alternative formulations, manufacturers need to trial these materials in house and trial the end products in application. There will be certain applications where formulation change is a impossible. However there still needs to be an alternative in preparation for the inevitable legislation and bans.

 What next?

There are alternative peroxides, Initially, that current suppliers will be able to offer for both solid and sponge applications, Alternatively there is Platinum cure systems. I feel that platinum cure is the best option from a health and safety perspective, in regard to physical property platinum cure will have more positive effects, however the end physical properties will determine the curing system needed to be implemented. When platinum curing is discussed in the industry, the first thought is always say “Yes, but its very expensive and processing conditions are prohibitive”. This statement is both correct and incorrect. Yes, there some platinum compounds or platinum masterbatch systems that are expensive. But if you are able to compound your own material either via 2 roll mill or internal mixer you do have the capabilities to compound platinum at the same price as DCBP compound or 1-3% higher price. You do need to take precautions when compounding platinum and also when processing the compound. This processing of new material need to start now in order to gain the experience of the systems, when the day comes and the ban is implemented manufacturers will have to use platinum and they DO have the capabilities and knowledge to make platinum cured silicone.