摘要:
Solid compositions of organosiloxane block copolymers are disclosed having a refractive index greater than 1.5. The organosiloxane block copolymers comprise: 40 to 90 mole percent disiloxy units of the formula [R12SiC2/2] 9 10 to 60 mole percent trisiloxy units of the formula [R2SiO3/2] 0.5 to 35 mole percent silanol groups [≡SiOH] where R1 is independently a C1 to C30 hydrocarbyl, R2 is independently a C1 to C20 hydrocarbyl, wherein; the disiloxy units [R12SiC2/2] are arranged in linear blocks having an average of from 10 to 400 disiloxy units [R12SiC2/2] per linear block, the trisiloxy units [R12SiC3/2] are arranged in non-linear blocks having a molecular weight of at least 500 g/mol, and at least 30% of the non-linear blocks are crosslinked with each other, each linear block is linked to at least one non-linear block, and the organosiloxane block copolymer has a molecular weight (Mw) of at least 20,000 g/mole.
摘要:
The present disclosure provides aqueous silicone emulsions of a “resin-linear” organosiloxane block copolymers. The present disclosure further provides a process for making these emulsions by forming a mixture of an organosiloxane block copolymer, admixing a sufficient amount of water to the mixture from to form an emulsion, and optionally further shear mixing the emulsion. The present invention further relates to the cured and/or coating compositions prepared from the present emulsions.
摘要:
Solid compositions of organosiloxane block copolymers are disclosed having a refractive index greater than 1.5. The organosiloxane block copolymers comprise: 40 to 90 mole percent disiloxy units of the formula [R12SiC2/2] 9 10 to 60 mole percent trisiloxy units of the formula [R2 SiO3/2] 0.5 to 35 mole percent silanol groups [≡SiOH] where R1 is independently a C1 to C30 hydrocarbyl, R2 is independently a C1 to C20 hydrocarbyl, wherein; the disiloxy units [R12SiC2/2] are arranged in linear blocks having an average of from 10 to 400 disiloxy units [R12SiC2/2] per linear block, the trisiloxy units [R12SiC3/2] are arranged in non-linear blocks having a molecular weight of at least 500 g/mol, and at least 30% of the non-linear blocks are crosslinked with each other, each linear block is linked to at least one non-linear block, and the organosiloxane block copolymer has a molecular weight (Mw) of at least 20,000 g/mole.
摘要:
Solid compositions of organosiloxane block copolymers are disclosed having a tensile strength greater than 1.0 MPa and a % elongation at break greater than 40%. The organosiloxane block copolymers comprise: 40 to 90 mole percent disiloxy units of the formula [R12SiO2/2] 10 to 60 mole percent trisiloxy units of the formula [R2SiO3/2] 0.5 to 35 mole percent silanol groups [≡SiOH] where R1 is independently a C1 to C30 hydrocarbyl, R2 is independently a C1 to C20 hydrocarbyl, wherein; the disiloxy units [R12SiO2/2] are arranged in linear blocks having an average of from 10 to 400 disiloxy units [R12SiO2/2] per linear block, the trisiloxy units [R2SiO3/2] are arranged in non-linear blocks having a molecular weight of at least 500 g/mol, and at least 30% of the non-linear blocks are crosslinked with each other, each linear block is linked to at least one non-linear block, and the organosiloxane block copolymer has a molecular weight (Mw) of at least 20,000 g/mole.
摘要:
A method for controlling morphology of a silicone organic block copolymer includes adding an MQ resin to the silicone organic block copolymer and annealing. The method is useful for forming thin films, which are useful in electronic device fabrication. The method is also useful for forming adhesives, release coatings, and reversible elastomers.
摘要:
Organosiloxane block copolymers, curable compositions, and solid compositions derived from these block copolymers are disclosed. The organosiloxane block copolymers comprise: 40 to 90 mole percent disiloxy units of the formula [R12—SiO2/2] 10 to 60 mole percent trisiloxy units of the formula [R2SiO3/2] 0.5 to 35 mole percent silanol groups [≡SiOH] where R1 is independently a C1 to C30 hydrocarbyl, R2 is independently a C1 to C20 hydrocarbyl, wherein; the disiloxy units [R12SiO2/2] are arranged in linear blocks having an average of from 10 to 400 disiloxy units [R12SiO2/2] per linear block, the trisiloxy units [R2SiO3/2] are arranged in non-linear blocks having a molecular weight of at least 500 g/mol, and at least 30% of the non-linear blocks are crosslinked with each other, each linear block is linked to at least one non-linear block, and the organosiloxane block copolymer has a molecular weight (Mw) of at least 20,000 g/mole.
摘要:
The present disclosure provides aqueous silicone emulsions of a “resin-linear” organosiloxane block copolymers. The present disclosure further provides a process for making these emulsions by forming a mixture of an organosiloxane block copolymer, admixing a sufficient amount of water to the mixture from to form an emulsion, and optionally further shear mixing the emulsion. The present invention further relates to the cured and/or coating compositions prepared from the present emulsions.
摘要:
A process is disclosed for preparing a resin-linear organosiloxane block copolymer by reacting in a first step an endcapped linear organosiloxane and an organosiloxane resin to form a resin-linear organosiloxane block copolymer. The resulting resin-linear organosiloxane block copolymer is then crosslinked in a second step to sufficiently increase the average molecular weight of the resin-linear organosiloxane block copolymer by at least 50%. The resin-linear organosiloxanes block copolymers prepared by the disclosed process may provide optically solid compositions which may be considered as “reprocessable”.
摘要:
This invention relates to thermoplastic elastomers comprising at least one silicone ionomer. These thermoplastic elastomers may be reprocessed and/or recycled.