Abstract: Metal containing polymer compositions, useful for the production of high temperature metal carbide ceramics are described, including poly(carbohafnocene) compositions and related poly(carbometallocene) compositions, as well as compositions formed from the reaction of hafnium chloride and 2-butyne-1,4-diol. Methods of synthesizing such compositions are provided.

Abstract: A process for forming a new group of siloxane-based compositions by a one-step co-hydrolysis and the compositions formed thereof. The siloxane-based compositions being functionalized with a carbon-carbon double (C?C) bond and a silicon-hydrogen (Si—H) bond. The C?C bond and hydrogen (H) each being attached directly to a silicon (Si) atom of the silicon-oxygen (Si—O) backbone of the siloxane-based composition. The C?C bond may be from a vinyl or an aromatic radical like a phenyl substituent. The C?C bond substituent provides the functionality needed for forming crosslinkages through standard dehydrocoupling catalysts without the need for siloxane fluids or organic compounds containing alkyl or aryl functional groups. The process provides for varying proportions of silanes as starting monomers to tailor the desired silicon, carbon, hydrogen and oxygen ratios in the siloxane-based compositions or resins.

Abstract: The invention provides branched copolymers as precursors for preparing silicon carbide (SiC) ceramics represented by the general formulae: [Si(˜)RC(˜)H]xn[SiR1R2CH2]yn,??Formula Type-I wherein n is the degree of polymerization, 0.1?x<0.8, 0.2?y<0.9 and x+y=1; and R=methyl or H, R1 and R2 are randomly composed of hydrogen (H), allyl, methyl (Me), phenyl (Ph), propargyl or vinyl. Another branched copolymer is represented by the general formula: [Si(˜)RC(˜)H]xn[SiR1R2CH2]yn[SiR3R4CH2]zn??Formula Type-II wherein n is the degree of polymerization, 0.1?x<0.8, 0?y<0.8, 0.2?z<0.8 and x+y+z=1; and R=methyl or H, R1 and R2 are randomly composed of hydrogen (H), methyl (Me) and phenyl; R3 and R4 are randomly composed of H, allyl, methyl, phenyl (Ph), propargyl, and vinyl. The invention also provides methods for the preparation of such branched copolymers.

Abstract: The invention provides a filter system and particulate filter unit therefor. The filter system may act as a purifier and a muffler for heavy and light duty diesel vehicles. The invention includes one or more combination filter units that remove particulates and nitrogen oxides in successive passes before the gas exits. A particulate filter unit may be used that removes additional particulates.

Abstract: The compound 2,4,6-trimethyl-2,4,6-trisila heptane, the preparation thereof, and the use thereof as a silicon carbide precursor in chemical vapor deposition and infiltration procedures are disclosed.

Abstract: The invention provides a filter system, a regeneration system, a combined soot-removing system and applications for the systems. The filter system may act as a purifier and a muffler for heavy and light duty diesel vehicles. The invention is a unique dual pass filter system that removes particulates and nitrogen oxides in successive passes before the gas exits the filter. The regeneration system includes an electric-powered heat source for safety and better control of the regeneration process. A motor vehicle application is also disclosed.

Abstract: The invention provides branched copolymers as precursors for preparing silicon carbide (SiC) ceramics represented by the general formulae: [Si(˜)RC(˜)H]xn[SiR1R2CH2]yn,??Formula Type-I wherein n is the degree of polymerization, 0.1?x<0.8, 0.2?y<0.9 and x+y=1; and R=methyl or H, R1 and R2 are randomly composed of hydrogen (H), allyl, methyl (Me), phenyl (Ph), propargyl or vinyl. Another branched copolymer is represented by the general formula: [Si(˜)RC(˜)H]xn[SiR1R2CH2]yn[SiR3R4CH2]zn??Formula Type-II wherein n is the degree of polymerization, 0.1?x<0.8, 0?y<0.8, 0.2?z<0.8 and x+y+z=1; and R=methyl or H, R1 and R2 are randomly composed of hydrogen (H), methyl (Me) and phenyl; R3 and R4 are randomly composed of H, allyl, methyl, phenyl (Ph), propargyl, and vinyl. The invention also provides methods for the preparation of such branched copolymers.