| 摘要 |
PROBLEM TO BE SOLVED: To provide a polysiloxane-based composition which is excellent in crack resistance during high-temperature heating, in addition to moldability, transparency, heat resistance and light resistance, and particularly, which uses liquid polyhedral structure polysiloxane, and to provide a hardened material thereof.SOLUTION: A polysiloxane-based composition includes: as essential components, a polyhedral structure polysiloxane modified body (A) which is obtained by modifying a polyhedral structure polysiloxane-based compound (a) containing an alkenyl group and/or hydrosilyl group with a compound (b) having a hydrosilyl group and/or alkenyl group, which can be hydrosilylated with the component (a); and hardening agents (B). The weight reduction at 130°C of (B) is 2.5% or less. |
