To provide an organic silicon compound having an average structural formula (1).

##STR00001##

(Z represents a 2 to 20-valent group containing an organosiloxane structure, each R.sup.1 independently represents an alkyl group or an aryl group, each R.sup.2 independently represents an alkyl group or an aryl group, each R.sup.3 independently represents a hydrogen atom, an alkyl group, an alkoxy group, or an O. (oxy radical), each R.sup.4 independently represents a hydrogen atom or an alkyl group, each A.sup.1 independently represents a single bond or an alkylene group free of a hetero atom, each A.sup.2 independently represents a single bond or a divalent linking group containing a hetero atom, m is a number of 1 to 3, p is a number of 1 to 10, q is a number of 1 to 10, and p+q represents a number satisfying from 2 to 20 corresponding to the valency number of Z.)

Methods of making prepregs are described. The methods include the steps of forming a fiber-containing substrate, and contacting the fiber-containing substrate with a resin mixture. The resin mixture may include polymer particles mixed in a liquid medium, and the polymer particles may be coated on the fiber-containing substrate to form a coated substrate. The liquid medium may be removed from the coated substrate to form the prepreg. The prepregs may be used to make fiber-reinforced articles.

A resin composition including the following components (a) and (b). (a) A polyimide precursor having a structural unit represented by the following general formula (1); and (b) a compound represented by the following general formula (2): wherein in the formula R.sup.1 is a tetravalent organic group, R.sup.2 is a divalent organic group and R.sup.3 and R.sup.4 are independently a hydrogen atom, an alkyl group, a cycloalkyl group or a monovalent organic group having a carbon-carbon unsaturated double bond. R.sup.5 is an alkyl group having 1 to 4 carbon atoms, R.sup.6 is independently a hydroxyl group or an alkyl group having 1 to 4 carbon atoms, a is an integer of 0 to 3, n is an integer of 1 to 6, and R.sup.7 is a group represented by the following general formula (3) or (4): wherein in the formula (3) or (4), R.sup.8 is an alkyl group having 1 to 10 carbon atoms or a monovalent organic group derived from hydroxyalkylsilane and R.sup.9 is an alkyl group having 1 to 10 carbon atoms, a monovalent organic group derived from aminoalkylsilane or a heterocyclic group, and R.sup.8 and R.sup.9 may independently have a substituent. ##STR00001##

Cationic silicon (II) compounds catalyze reaction of organosiloxanes bearing lateral SiH functions to crosslink the polymers. Hydridosilanes may also be prepared by this reaction. The cationic silicon (II) compounds contain a silicon (II) moiety where silicon is -bonded to a cyclopentadienyl anion.

Cationic silicon (II) compounds catalyze reaction of organosiloxanes bearing lateral SiH functions to crosslink the polymers. Hydridosilanes may also be prepared by this reaction. The cationic silicon (II) compounds contain a silicon (II) moiety where silicon is -bonded to a cyclopentadienyl anion.

An ultraviolet (UV) light stabilizing polymeric filler material includes a particle that is surface modified to include a hydroxyphenyl-benzotriazole (HPB) derivative functionality.

An organosiloxane composition and the use of such compositions is provided. The organosiloxane composition comprises (a) 20-55 wt. % of at least one polymerization-effective polymer bearing two or more silicon atoms; (b) 24-60 wt. % of a first filler of average particle size from 0.1 m to 10 m; (c) optionally a second filler; (d) a crosslinking agent; and (e) a catalyst. The use of the first filler having that size range and present in this amount provides improved dirt pick up resistance to films and coatings formed from the compositions.

An organosiloxane composition and the use of such compositions is provided. The organosiloxane composition comprises (a) 20-55 wt. % of at least one polymerization-effective polymer bearing two or more silicon atoms; (b) 24-60 wt. % of a first filler of average particle size from 0.1 m to 10 m; (c) optionally a second filler; (d) a crosslinking agent; and (e) a catalyst. The use of the first filler having that size range and present in this amount provides improved dirt pick up resistance to films and coatings formed from the compositions.

The present invention relates to a modified conjugated diene-based polymer, a method of preparing the same, and a rubber composition including the same, and more specifically provides a rubber composition which includes a repeating unit derived from a conjugated diene-based monomer having a trans-1,4 bond content of 80 wt % or more and a functional group derived from an alkoxysilane-based modifier, a method of preparing the same, and a rubber composition including the same.

A chemical mechanical polishing composition for polishing a substrate having copper, barrier, and dielectric layers includes a water based liquid carrier, cationic silica abrasive particles dispersed in the liquid carrier, and a triazole compound, wherein the polishing composition has a pH of greater than about 6 and the cationic silica abrasive particles have a zeta potential of at least 10 mV. The triazole compound is not benzotriazole or a benzotriazole compound. A method for chemical mechanical polishing a substrate including copper, barrier, and dielectric layers includes contacting the substrate with the above described polishing composition, moving the polishing composition relative to the substrate, and abrading the substrate to remove a portion of the copper, barrier, and dielectric layers from the substrate and thereby polish the substrate.