摘要:
Self-adhesive crosslinkable silicone compositions may be transparent and prepared without conventional adhesion promoters, and contain (1) an organopolysiloxane having a minimum of two aliphatically unsaturated carbon-carbon bond-containing groups, (2) a pendant Si—H functional organopolysiloxane having at least 3 Si—H groups and a minimum of 0.7 weight percent of Si-bonded hydrogen, and (3) a linear organopolysiloxane bearing terminal Si—H groups, wherein the mol ratio of silicon-bonded hydrogen in (2) to that in [(2) and (3)] is from 0.05 to 1.
摘要:
Photovoltaic modules are prepared by laminating an active device to a glass cover plate by means of a thermoplastic siloxane copolymer. The siloxane copolymer provides good adhesion, freedom from water absorption, and yet can be reworked either in the field or during recycling of the solar cell components.
摘要:
Hydrophilic siloxane copolymers are prepared by(a) reacting organopolysiloxanes having at least one Si-bonded hydrogen atom with substantially linear oligomeric or polymeric compounds of formula R1-(A-CnH2n)m-A1-H (I) where R1 is a monovalent optionally substituted, hydrosilylatable hydrocarbyl radical, A is a bivalent polar organic radical selected from —O—, —C(O)—O—, —O—C(O)—, —O—C(O)—O—, —C(O)—NH—, —NH—C(O)—, urethane radicals and urea radicals, A1 is a bivalent polar organic radical selected from —O—, —NH— and —NR′—, n is an integer from 1 to 20, and m is zero or a positive integer, (b) reacting the resulting intermediate with organic compounds which have two or more isocyanate groups, in the presence of further organic compounds (6) reactive toward isocyanate groups and containing at least one tertiary amine group, and (c) quaternizing the amino-group-containing intermediate from step (b) with an alkylating agent (8), with the proviso that the water content of the compounds (1) and (2) is lower than 2000 weight ppm.
摘要:
Cyclodextrinyl group-containing organosilicon compounds contain cyclodextrin or cyclodextrin derivatives bonded to an organosilicon moiety through a divalent linking group. The compounds are easily prepared in high yield by reaction of reactive cyclodextrin or cyclodextrin derivatives with an organosilicon compound reactive therewith. The compounds have numerous uses, including treatment of organic fibers to provide long lasting fragrances or freshness characteristics.
摘要:
Self-adhesive crosslinkable silicone compositions may be transparent and prepared without conventional adhesion promoters, and contain (1) an organopolysiloxane having a minimum of two aliphatically unsaturated carbon-carbon bond-containing groups, (2) a pendant Si—H functional organopolysiloxane having at least 3 Si—H groups and a minimum of 0.7 weight percent of Si-bonded hydrogen, and (3) a linear organopolysiloxane bearing terminal Si—H groups, wherein the mol ratio of silicon-bonded hydrogen in (2) to that in [(2) and (3)] is from 0.05 to 1.
摘要:
A process for preparing organopolysiloxanes bearing triorganosiloxy groups of defined structure involves reacting, in a first step, organopolysiloxanes having SiH groups with water in the presence of a metal of transition group VIII or compounds thereof as a catalyst, optionally in the presence of cocatalysts, to provide Si—OH group-containing intermediates, and, in a second step, reacting the intermediates bearing SiOH groups with silanes which have a group reactive toward SiOH groups. The reaction proceeds rapidly in high yield and with few byproducts.
摘要:
Organosilicon compounds bearing keto or aldehyde groups are easily prepared in high yield by oxidation of a carbinol-functional precursor by an oxidizing agent in the presence of a nitrogen-containing free radical mediator. The oxidation may be conventional, i.e. using air, oxygen, or other oxidant, may be electrochemical, or enzymatic.
摘要:
Crosslinkable organopolysiloxane compositions containing quaternary ammonium group-bearing organopolysiloxanes in minor amounts provide protection against microbial growth in moldings and sealants prepared therefrom.
摘要:
A process for preparing organopolysiloxanes bearing triorganosiloxy groups of defined structure involves reacting, in a first step, organopolysiloxanes having SiH groups with water in the presence of a metal of transition group VIII or compounds thereof as a catalyst, optionally in the presence of cocatalysts, to provide Si—OH group-containing intermediates, and, in a second step, reacting the intermediates bearing SiOH groups with silanes which have a group reactive toward SiOH groups. The reaction proceeds rapidly in high yield and with few byproducts.
摘要:
Organosilicon compounds bearing carboxylic acid groups are easily and economically replaced in high yield by oxidation of a carbinol-functional organosilicon compound with an oxidizer in the presence of a moderator at a pH≧3. Carboxyl-functional organopolysiloxanes highly useful as textile softeners may be obtained by this method.