In addition-cured silicone systems, the structure and purity of the crosslinker directly affect curing efficiency and final performance. End-functional hydrogen-containing phenyl silicone oil IOTA-234 (Chemical Name: 3,5-Bis(dimethylsiloxy)-1,1,7,7-tetramethyl-3,5-diphenyltetrasiloxane, CAS: 66817-59-2) is a high-purity, low-molecular-weight hydrogen-containing phenyl siloxane. Thanks to its well-defined molecular structure and excellent reactivity, it has become a key crosslinking component in high-end phenyl silicone rubber and silicone resin systems.
IOTA-234 is a colorless, transparent liquid with a density of approximately 1.005, refractive index (20 °C) of 1.4622, boiling point 95–96 °C (0.25 mmHg), and flash point above 110 °C (COC). Gas chromatography analysis shows a purity of ≥95% with low impurity content, ensuring minimal side reactions and controllable gelation time during platinum-catalyzed addition reactions. Its molecular structure introduces active Si-H bonds at both chain ends and in the side chains, while containing phenyl units, ensuring high crosslinking efficiency and imparting excellent thermal stability and flexibility to the cured network.
This product is compatible with methyl silicone oils, liquid silicone rubbers, phenyl silicone rubbers, and phenyl silicone resins. It is widely used to prepare elastomers and coatings with high/low temperature resistance, high insulation, or radiation resistance. Typical applications include aerospace sealants, LED encapsulants, high-reliability electronic potting compounds, and heat-resistant silicone resin coatings.
User feedback indicates that IOTA-234 disperses uniformly in formulations, yielding cured products with low shrinkage, high transparency, and stable mechanical performance over a wide temperature range of –50 °C to 250 °C, outperforming some traditional linear hydrogen-containing silicone oils.
The product is packaged in 25 kg or 200 kg internally coated steel drums, transported as non-hazardous material, and should be stored sealed in a cool, ventilated, dry place, avoiding contact with moisture, alkaline substances, or residual catalysts.
As high-end manufacturing continues to demand enhanced silicone material performance, IOTA-234 and similar high-purity, structurally precise specialty crosslinkers are becoming critical to the autonomous, high-performance production of domestic silicone rubbers and resin systems.
