FUNCTIONAL POLYORGANOSILOXANES AND CURABLE COMPOSITION BASED ON SAID POLYORGANOSILOXANES Russian patent published in 2010 - IPC C08G77/20 C08L83/07 H01L33/56 

FIELD: chemistry.

SUBSTANCE: invention relates to functional polyorganosiloxanes included in compositions suitable for producing optical materials. The invention discloses novel functional polyorganosiloxanes containing two or more vinyl groups on average per macromolecule, the average composition of which includes several building blocks whose structure and quantitative ratio are expressed by general formula (R² ₃SiO_1/2)_a-(C₆H₅)₂SiO_2/2)_b(R¹SiO_3/2)_c-(C₆H₅SiO_3/2)_d-(R¹R^'2SiO_2/2)_e (I), where R¹ - CH₂=CH-; R² - CH₃- or C₆H₅-; denotation from a to e represent molar ratios of links, the sum of which is equal to 1, and their values are: a=0.15-0.4; b=0.1-0.2; c=0.15-0.4; d=0.2-0.4; e=0-0.2. Disclosed also is a curable organosilicon composition which contains: functional polyorganosiloxane from the family of polyorganosiloxanes of formula (I); polyorganohydride siloxane containing two or more hydrogen atoms bonded to silicon atoms in each molecule and a hydrosilation catalyst. The refraction index of the cross linked product is equal to or greater than 1.5. The composition is meant for encapsulating light-emitting devices.

EFFECT: disclosed functional polyorganosiloxanes are suitable for preparing curable compositions used for encapsulating optical devices, compared to existing encapsulants, the solidification products have better properties, specifically high refraction index, thermal- and weather resistance.

15 cl, 2 tbl, 3 dwg, 4 ex