Abstract:
Enhancement of the rates of cationic polymerizations initiated by onium salts has been achieved through the use of oligomeric and polymeric electron-transfer photosensitizers derived from a polymerizable compound substituted with a polynuclear aromatic group, including epoxides, oxetanes, and ethylenically unsaturated compounds. The polymerizable compound is substituted with residues derived from anthracene, naphthalene, perylene, pyrene, fluorene, carbazole, indole, benzocarbazole, acridone, phenothiazine, and thianthrene, particularly carbazole.
Abstract:
The invention provides a method for making a curable epoxysilicone composition through the hydrosilation reaction between an ethylenically unsaturated epoxide and an SiH-containing silicone to produce an epoxysilicone product, and catalyzed by a quaternary ammonium, phosphonium or arsonium hexahaloplatinate which does not promote the oxirane ring-opening reaction of either the ethylenically unsaturated epoxide starting material or the epoxysilicone product. The invention also provides for a curable epoxysilicone composition made by the above method.
Abstract:
A process for the selective monoadditon of an olefin or acetylene to a siloxane which contains two reactive Si--H bonds to produce a product in which only one of the two Si--H functions has added across the olefin or acetylene is disclosed. A process for making unsymmetrical siloxanes from symmetrical dihydrosiloxanes and products of both of these processes are also disclosed. Products are represented by the formula I in which R.sup.1 and R.sup.4 are different: ##STR1##
Abstract:
A catalyst: mixture for ring-opening polymerization of heterocyclic monomers and polymers includes a catalyst composed of a cobalt carbonyl complex; and a cocatalyst composed of at least one Si-H-containing compound. A curable composition, which may be a two-part kit, is also disclosed and includes the catalyst; the cocatalyst; and at least one polymerizable compound which is a monomer or polymer containing a heterocyclic ring. A method of producing a polymeric product by ring-opening polymerization of heterocyclic monomers and polymers is also disclosed which includes the steps of preparing a mixture including a catalyst composed of a cobalt carbonyl complex, a cocatalyst composed of at least one Si-H-containing compound, and at least one polymerizable compound which is a monomer or polymer containing a heterocyclic ring; and reacting the mixture, preferably at about room temperature, to promote ring-opening polymerization of the at least one polymerizable compound to produce the polymeric product.
Abstract:
The present invention is based on the discovery that various metal catalysts will catalyze the ring opening polymerization of epoxides to yield polyethers. The present invention therefore provides a method of making a polymeric product by ring-opening polymerization of heterocyclic epoxide monomer including the steps of preparing a mixture comprised of a catalyst; a Si--H containing compound; and at least one compound which is a heterocyclic epoxide containing monomer; and reacting the mixture at a temperature effective to promote ring-opening polymerization of the at least one compound to produce a polymeric product, preferably at room temperature.The present invention additionally provides for the silicone-polyether compositions created by this method.
Abstract:
A highcarbon-containing diaryliodonium initiator for cationic polymerization which possesses enhanced solubility characteristics over conventional diaryliodonium initiators. By the disclosed process, a novel photo/thermal initiator is obtained which is uniquely characterized by the concatenation of a long chain ester with an aryl group, resulting in a total number of carbon atoms in the entire moiety attached to the iodine atom in excess of 20.
Abstract:
A heat curable composition is provided which is useful for encapsulating microelectronic devices using a heat curable epoxy composition having a diaryliodonium hexafluoroantimonate salt as a catalyst in combination with an effective amount of a free radical generating aromatic compound as a cocatalyst.
Abstract:
Block polymer compositions are provided which are useful as positive or negative resists utilizing aryl onium salts in combination with silicone-organic block polymers, such as polydimethylsiloxane-poly-t-butylmethacrylate block polymers. A silicone prepolymer is used in combination with certain polymerizable vinyl monomers such as t-butylmethacrylate. The silicone prepolymer has chemically combined pinacolate groups in the backbone or terminal positions which are capable of generating free-radicals upon thermolysis.
Abstract:
Aryliodonium salts resulting from the condensation of aryliodosotosylates and aryl ketones are provided which are used as photoinitiators to effect deep section UV cures. Deep section photopolymerizable organic materials are also provided which can be used as encapsulating agents to encapsulate a wide variety of electronic components.
Abstract:
Photo-curable vinyloxy-functional organosiloxane polymers are provided. Also provided are release coating compositions made by combining said polymers with various photo-initiators. The polymers have a unique vinyloxy functionality; and the release coating compositions cure with brief exposure to ultraviolet radiation to form premium abhesive coatings. Process for preparing the vinyloxy-functional polysiloxanes and the release coating are also disclosed.