Radiation Vulcanization of Natural Rubber Latex

What is radiation vulcanization of natural rubber latex?

Radiation vulcanization of natural rubber latex is a method of vulcanizing natural rubber latex by using ionizing radiation. Vulcanization refers to a process of introducing chemical bonding between rubber molecules, i.e. crosslink, within latex and forming three dimension networks that are able to enhance the elasticity and overall mechanical properties of the latex.  Conventionally, vulcanization is achieved by heating latex together with sulfur, whereas radiation vulcanization is a non-sulfur vulcanization method that does not require the presence of sulfur during the vulcanization process.


How to vulcanize natural rubber latex by using radiation?

Theoretically, radiation vulcanization of natural rubber latex can be accomplished by merely exposing natural rubber latex to high energy ionizing radiation such as gamma ray or electron beam. However, it may require a big amount of radiation, or radiation dose, for the latex to achieve an acceptable level of mechanical properties. Hence, prior to irradiation, acrylate monomer together with stabilizer will be added to natural rubber latex. The presence of acrylate monomer will reduce the radiation dose required for achieving optimum latex mechanical properties to a reasonable amount. Radiation prevulcanized natural rubber latex is collected at the end of irradiation process.  A simplified radiation vulcanization process is shown in the following animated diagram.

What is the application of radiation vulcanized natural rubber latex?

Radiation vulcanized natural rubber latex is claimed to be free from sulfur, cytotoxicity and chemical accelerators induced allergy. Hence, it would be a potential material for latex dipped products such as rubber gloves, finger cots, baby teats, and other thin rubber products that are friendly to users and environment.