Abstract:
Pressure sensitive adhesives (PSA) having a reduced volatile fraction content are provided by a process which comprises extracting a cured PSA with a fluid in or near its supercritical state. The process provides PSAs and articles containing PSAs which meet the volatility requirements of ASTM E-595. A silicone PSA transfer film having utility in outer space is obtained.
Abstract:
Pressure sensitive adhesives (PSA) having a reduced volatile fraction content are provided by a process which comprises extracting a cured PSA with a fluid in or near its supercritical state. The process provides PSAs and articles containing PSAs which meet the volatility requirements of ASTM E-595. A silicone PSA transfer film having utility in outer space is obtained.
Abstract:
Addition-curable silicone pressure sensitive adhesives can be covered with an addition-cured fluorosilicone release coating to provide a releasable laminate. The release force of the laminate is low to moderate and the subsequent adhesion and tack of the adhesive is high and all three values are stable with time. The laminate can be prepared by contacting the release coating with cured adhesive or by curing the adhesive in contact with the release coating.
Abstract:
Aminofunctional siloxanes, such as siloxanes bearing ethylenediamine-substituted hydrocarbon radicals, have their amine functionality fully modified by reaction with a monocarboxylic acid anhydride. The modifying functionality includes complete diamide or amide-amine salt formation. The amide-amine salt functionality can further be converted to a mixture of diamide and amide-amine functionality, if desired. The modified aminofunctional siloxanes have utility as components in hair care compositions, textile treating compositions and moldable polymeric compositions.
Abstract:
A new organohydrogenpolysiloxane compound and a new fluorosilicone polymer each have unique properties which allow for the preparation of faster curing coating compositions having longer bath life than those disclosed in the art. In a preferred embodiment the new polymers are mixed together to provide, along with a metal-containing hydrosilylation catalyst and a catalyst inhibitor to provide improved coating compositions which are useful for preparing a release linear to protect silicone pressure sensitive adhesives.
Abstract:
A new organohydrogenpolysiloxane compound and a new fluorosilicone polymer each have unique properties which allow for the preparation of faster curing coating compositions having longer bath life than those disclosed in the art. In a preferred embodiment the new polymers are mixed together to provide, along with a metal-containing hydrosilylation catalyst and a catalyst inhibitor to provide improved coating compositions which are useful for preparing a release liner to protect silicone pressure sensitive adhesives.
Abstract:
Dual zone porous materials having an external zone and an internal zone are prepared by contacting a suspension of a porous support, such as particulate silica, in an aprotic solvent with an organosilane mixture of a first organosilane having first silyl groups and a second organosilane of a second type in order to form first silyl groups predominantly or the external surfaces of the porous support and second silyl groups predominantly on the internal surfaces of the porous support.
Abstract:
Silicone pressure sensitive adhesive compositions which cure in the presence of moisture comprise an adhesive component which bears alkoxy radical-containing curing radicals and, optionally, a catalyst to accelerate the reaction of moisture with the alkoxy radicals to form siloxane bonds. Curing provides adhesives ranging from pressure sensitive adhesives having improved properties to permanent adhesives. The adhesives are useful for adhering an object to a surface and thereafter improving the bond between the object and the surface by exposure to moisture.
Abstract:
Porous materials having a dual surface are disclosed. Also disclosed is a method for their preparation. An example of such a material is silica gel reacted with 1,1,1-trifluoropropyldimethylsilyl-N-methylacetamide and then, with N-trimethylsilyl-N-methylacetamide to give a dual treated material having 1,1,1-trifluoropropyldimethylsilyl groups on the exterior surface and trimethylsilyl groups on the porous interior surface.
Abstract:
The subsequent tack and adhesion of a silicone pressure-sensitive adhesive can be improved by incorporating into the adhesive a small amount of an organopolysiloxane resin having a majority of R.sub.3 SiO.sub.1/2 siloxane units and the balance (R.sup.2 O).sub.a SiO.sub.(4-a)/2, preferably SiO.sub.4/2, siloxane units. The resulting composition, when brought into contact with a release liner, such a peelable protective sheet or the backside of the next turn in a roll of tape, have better tack and/or adhesion when separated from that liner than an analogous composition which does not contain the resin.