A siloxirane based no-flow underfill material is provided. The material has a low coefficient of thermal expansion, low moisture uptake and a high distortion temperature. The material typically includes at least an epoxy siloxiane resin, a cross-linking hardener, a catalyst, and a fluxing agent.

The present invention relates to a novel oxirane pre-polymer comprised of the catalyzed or uncatalyzed reaction product of phenyl intermediates with a difunctional oxirane oligomer having at least one aromatic moiety and at least one aliphatic moiety, characterized in that substantially hydrolyzable oxygen atoms in said phenyl are bonded to said oligomers, and there is substantially no bonding between oligomer moieties. In a particularly preferred embodiment the present invention relates to a novel oxirane prepolymer comprising the reaction product of a phenyl intermediate with an inorganic oxide having at least one hydrolyzable oxygen and a difunctional oxirane oligomer aliphatic moiety characterized in that a majority of all hydrolyzable oxygen atoms in said oxide are bonded to at least one of the phenyl groups of the intermediate phenyl and one phenyl group is bonded to said oligomer and there is substantially no bonding between oligomer moieties.

The present invention relates to a novel oxirane pre-polymer comprised of the catalyzed or uncatalyzed reaction product of tris or tetraphenyl intermediates with a difunctional oxirane oligomer having at least one aromatic moiety and at least one aliphatic moiety, characterized in that substantially hydrolyzable oxygen atoms in said phenyl are bonded to said oligomers, and there is substantially no bonding between oligomer moieties. In a particularly preferred embodiment the present invention relates to a novel oxirane prepolymer comprising the reaction product of a phenyl intermediate with an inorganic oxide having at least one hydrolyzable oxygen and a difunctional oxirane oligomer aliphatic moiety characterized in that a majority of all hydrolyzable oxygen atoms in said oxide are bonded to at least one of the phenyl groups of the tris-phenyl and one phenyl group of the tris-phenyl group is bonded to said oligomer and there is substantially no bonding between oligomer moieties. The present invention also relates to a novel pre-polymer, said pre-polymer comprising of three aromatic groups cross-linked through a carbon ethane group, said aromatic groups having three hydroxyl groups, the prepolymer moiety being the reaction product of one hydroxyl group with one oxirane group of a difunctional oxirane oligomer having at least one aromatic moiety and at least one oxirane aliphatic moiety.

The invention relates to a curable composition comprising (A) particles prepared by bonding at least one oxide of an element selected from the group consisting of silicon, aluminum, zirconium, titanium, zinc, germanium, indium, tin, antimony, and cerium, and an organic compound which comprises a polymerizable group, (B) a compound having a melamine group and one or more polymerizable groups and (C) a compound having at least two polymerizable groups in the molecule other than the component (B); and to cured products and laminates with a with low reflectance and superior chemical resistance.

A method is provided for polymerizing oxiranes by employing a lithium-containing polymerization initiator in a liquid reaction medium devoid of polymerization additives. Linear and star polymers can be produced by practicing the subject method.