Silicone rubber heat resistant agent nano cerium oxide

型号：

VK-Ce01

氧化铈（CeO2）（w）%：

99.99

粒径：

50纳米

,
,
Basic information
Nano-cerium oxide, also known as nano-cerium dioxide,
Silicone rubber mainly undergoes main chain thermogravimetry in a high-temperature, airtight, oxygen-free state. Degradation occurs, that is, a depolymerization reaction occurs, causing the product to become soft (or softened), resulting in the loss of mechanical strength and use value. Under high-temperature aerobic environmental conditions, oxidation of polymer side groups mainly occurs, forming alkyl radicals. The coupling reaction of free radicals leads to an increase in the cross-link density of the seal, causing the product to gradually harden and even crack (called hardening).
Adding cerium oxide to silicone rubber can prevent oxidative cross-linking of polysiloxane side chains and cyclization degradation of the main chain. It can prevent the free radical reaction caused by oxidation in silicone rubber within a certain temperature range, and can be regenerated under the influence of air by absorbing some trace amounts of acid or alkaline substances in silicone rubber that can catalyze the degradation reaction, thereby It has a thermal stabilizing effect on silicone rubber.
At the same time, the special electronic structure of cerium oxide (the electron layer is not full) makes it easy to form complexes. The formed complexes inhibit the swelling of rubber in the solvent by preventing the chain segment movement of rubber molecules, thereby improving the Improves the oil resistance of rubber.
Qingdao University of Science and Technology Key Laboratory of Rubber and Plastic Materials and Engineering Ministry of Education Adding cerium oxide has a small impact on the mechanical properties of silicone rubber, but it can improve the heat resistance of silicone rubber and significantly improve its oil resistance. Cerium oxide The optimal dosage is serving. It can be seen from the thermal analysis that compared with the silicone rubber without cerium oxide, the peak thermal decomposition temperature of the silicone rubber with cerium oxide added in the nitrogen environment is increased by ℃, and the peak value of the first stage thermal decomposition temperature in the air is increased by ℃. , the second stage increased the ℃, indicating that cerium oxide has a thermal stabilizing effect on silicone rubber.
Technical indicators
Item
Indicators
Model

Cerium oxide%

Average particle size



+










Packaging kg/barrel