| 摘要 |
PURPOSE: To obtain an organopolysiloxane compsn. which is used for a plastic optical fiber, has a low viscosity, can be easily poured into a cladding material in the shape of a tube, and converts, when heated after the pouring, into a high-viscosity organosiloxane suitable as a core material. CONSTITUTION: This compsn. comprises an organopolysiloxane having on average two alkenyl groups per molecule, an organopolysiloxane having on average two silicon-bonded hydrogen atoms per molecule, and a platinum-group metal catalyst, has a viscosity of 5,000cP or lower at 25 deg.C, and converts, when heated, into an organopolysiloxane having a viscosity of 10,000cP or higher at 25 deg.C and a viscosity of a 10wt.% toluene soln. of 50,000cSt or lower. |
