| abstract |
The present disclosure provides methods of making organosiloxane polymer compositions from hydrosilylation curable compositions comprising at least the components (a) and (b) and at least one of components (c) and (d): (a) an organosiloxane resin material comprising aliphatic unsaturation; and (b) an organosiloxane crosslinker comprising multiple silicon atom-bonded hydrogen atoms (e.g., an “SiH siloxane”); in combination with at least one of (c) at least one organosiloxane comprising at least two silicon atom-bonded hydrogen atoms; and (d) at least one organosiloxane comprising at least two silicon atom-bonded hydrocarbyl groups comprising aliphatic unsaturation (e.g., a “di-vinyl functional siloxane”). Such hydrosilylation curable compositions have, in some instances, significantly faster cure speed, relative to their condensation curable counterparts. A faster cure speed can be important for encapsulating electronic devices, such as light-emitting diode (LED) chip devices, including devices having tall structures. |