Abstract:
A method is provided for making silicone-organic block polymers, such as polydimethylsiloxane-polystyrene block polymers resulting from the thermal generation of free-radicals in the presence of free-radical polymerizable organic monomer. A silicone prepolymer is used having chemically combined pinacolate groups the in backbone or terminal positions which are capable of generating free-radicals upon thermolysis and which retain chemically combined remnants of such pinacolate diradicals which serve as connecting sites for free-radical polymerized organic blocks.
Abstract:
Aromatic polyvinylethers and active hydrogen compound reaction products thereof have been found to provide fast heat curable molding compositions when used with various heat activated curing catalysts, for example, diaryliodonium salts in combination with aromatic polyvinylether soluble copper compounds, or dialkylhydroxyarylsulfonium salts in combination with certain organic oxidants.
Abstract:
A method is provided for making certain diaryliodonium salt photoinitiators, based on the initial formation of diaryliodonium perchlorate which is formed from a diaryliodonium bisulfate precursor. The diaryliodonium perchlorate is then reacted with a counter ion source, such as an alkali metal hexafluoro metalloid salt, to produce the desired diaryliodonium salt, which can be used as a photoinitiator. The iodonium salt photoinitiators made by the method of the present invention can be used to effect the cure of a variety of cationically polymerizable organic materials, such as epoxy resins.
Abstract:
Cationic polymerization of epoxy monomers or prepolymers can be achieved by use of certain radiation sensitive aromatic halonium salts. Curable compositions are provided which can be used as sealants, coating compounds, encapsulants, etc.
Abstract:
Aromatic onium salts, such as diaryliodonium salts, have been found to be effective thermal initiators for the polymerization of epoxy resins having a viscosity of up to about 100,000 centipoises at 25.degree. C. when used in combination with copper salts. The processable epoxy resin composition can be used in filament winding and pultrusion applications.
Abstract:
Halogen onium salts, and onium salts of Group VA and V1A elements having an MF.sub.6.sup.- anion, where M is selected from P, As and Sb, have been found to exhibit unusual activity under ultraviolet light. These onium salts can be employed as cationic photoinitiators when used with a variety of organic resins and cyclic organic compounds.
Abstract:
A method is provided for making certain aryl onium salts of Group VIa elements useful as photoinitiators for polymerizing various organic materials. Reaction is effected between a compound of a Group VIa element, for example, an aryl or alkyl sulfide or a thiophenol or mercaptan and an aromatic iodonium salt in the presence of a copper compound catalyst or a copper compound-tertiary amine cocatalyst.
Abstract:
A method is provided for making certain diaryliodonium salt photoinitiators, based on the initial formation of a diaryliodonium bisulfate. Methylene chloride is substituted for acetic acid during the reaction between potassium iodate and benzene in the presence of acetic anhydride and sulfuric acid. The diaryliodonium bisulfate is then reacted with a counterion source, such as a metal salt, to produce the desired diaryliodonium salt which can be used as a photoinitiator. The iodonium salt photoinitiators made by the method of the present invention can be used to make UV curable compositions.
Abstract:
Low temperature curable organic resin compositions, for example, epoxy resins are provided, which can be either exothermically cured or cured in several minutes or less at relatively low temperatures. Certain diaryliodonium salts have been found to spontaneously release strong protonic acids when used in combination with a copper salt and a reducing agent.
Abstract:
Cationic polymerization of epoxy resin materials, such as epoxy monomers or prepolymers, can be achieved by use of certain radiation sensitive aromatic onium salts of Group VIa elements. Curable compositions are provided which can be used as sealants, coating compounds, encapsulants, etc.