Year1
- 型号：
- VK-Ce201
- 粒径nm：
- 50
- 含量%：
- 99.99
< >#:
< >Silicone rubber mainly undergoes thermal rearrangement and degradation of the main chain in a high-temperature, airtight, oxygen-free state, that is, a depolymerization reaction occurs, making the product soft (or softened ), resulting in 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 the rubber in the solvent by preventing the chain segment movement of the rubber molecules. This improves the oil resistance of the rubber.
< >The addition of cerium oxide to the Key Laboratory of Rubber and Plastic Materials and Engineering of the Ministry of Education of Qingdao University of Science and Technology 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. The preferred dosage of cerium oxide is parts. 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:
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Packing: Kilogram cardboard drum
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