Why does transparent silicone tubing yellow, and how can it be slowed?
Yellowing in transparent silicone tubing has several causes, and the dominant one in most service environments is thermo-oxidative aging: sustained heat exposure causes oxidation of the polymer chains, generating chromophoric groups that absorb visible light. In peroxide-cured tubing specifically, decomposition residuals from the vulcanizing agent — such as organic acids — are a direct contributor to yellowing, as they remain in the material matrix after curing and react with time and heat. UV exposure triggers photooxidation through a separate mechanism, while contact with nitrogen oxides, ozone, or certain chemicals in the environment can initiate surface discoloration independently.
The most effective countermeasure is switching to a platinum-catalyzed addition cure system. Because the reaction produces no organic acid byproducts and does not require a high-temperature post-cure cycle to drive off residuals, the resulting tubing has significantly better long-term color stability. Ruixiang’s medical-grade and food-grade transparent silicone tubing is produced exclusively using a platinum-catalyzed addition cure process and remains colorless and transparent after extended storage and repeated autoclave sterilization.
For product specifications, technical data sheets, or sample requests, contact the Ruixiang team: olivia@dgruixiang.com | www.medicalsiliconetube.com