Abstract:
A new electro-optic (EO) phase modulator constructed from a combination of a low-loss passive polymer waveguide and a self-assembled chromophore superlattice (SAS) with an intrinsically polar microstructure. In contrast to typical polymer-based modulators, the present invention utilizes a siloxane SA methodology that enables the acentric alignment of constituent chromophores during film growth without the need for post-deposition electric field poling. The guiding layer is constructed of the SAS and the glassy polymer Cyclotene™. The use of SiO2, Cytop™ and Cyclotene™ glassy polymers, results in a straightforward device fabrication process that is compatible with the thermally and photochemically robust SAS. Thus, nanoscale control of the film architecture results in greatly simplified macroscopic device fabrication. The present invention provides a SAS-based electro-optic modulator demonstrating excellent electro-optic response properties and a &pgr; phase shift.
Abstract:
New organic light-emitting diodes and related electroluminescent devices and methods for fabrication, using siloxane self-assembly techniques.
Abstract:
A process for treating a composition containing a substantial proportion of trimethyflolpropane bis-monolinear formal (TMP-BMLF) or trimethylolethane bis-monolinear formal (TME-BMLF), e.g., a heavy ends residue obtained from the purification of a crude trimethylolpropane (TMP) or trimethylolethane (TME) product, wherein the composition is contacted at an elevated temperature with a strong acid catalyst, e.g., methanesulfonic acid, to produce a composition containing significantly increased amounts of TMP and trimethylolpropane monocyclic formal (TMP-MCF) or TME and trimethylolethane monocyclic formal (TME-MCF) respectively. Also disclosed is a process for reacting TMP-MCF or TME-MCF, either in substantially pure form or as present in the light ends overhead stream obtained in a finishing treatment of crude TMP or TME, with a monohydric or dihydric alcohol, e.g., ethylene glycol, in the presence of a strong acid catalyst to obtain additional TMP or TME and an acetal by-product, e.g., 1,3-dioxolane; and a process for directly reacting the TMP-BMLF or TME-BMLF present in a composition, e.g., the heavy ends residue obtained in the purification of TMP or TME, with a monohydric or dihydric alcohol, e.g., ethylene glycol, in the presence of a strong acid to obtain additional TMP or TME and an acetal by-product, e.g., 1,3-dioxolane.
Abstract:
A ruthenium-containing metathesis catalyst system which contains a ruthenium compound (A), a phosphorus compound (B), and a compound (C) containing a carbon-to-carbon triple bond. The mole ratio of compounds A:B:C is typically in the range of about 1.0:0.01-100:0.01-100. The ruthenium compound (A) is a Ru(II), Ru(III), or Ru(IV) compound containing an anionic ligand (X) and optionally an arene ligand and optionally a phosphorus compound ligand. The phosphorus compound (B) is optional if the ruthenium compound (A) contains a phosphorus-containing ligand. The catalyst system is employed in processes to metathesize olefins, including ring-opening metathesis polymerization of cyclic olefins, metathesis of acyclic olefins, acyclic diene metathesis oligomerization or polymerization, cross-metathesis of cyclic and acyclic olefins, ring-closing metathesis, metathesis depolymerization of unsaturated polymers, and metathesis of functionalized olefins.
Abstract:
Group 3-6 or Lanthanide metal complexes possessing two metal centers, catalysts derived therefrom by combining the same with strong Lewis acids, Bronsted acid salts, salts containing a cationic oxidizing agent or subjected to bulk electrolysis in the presence of compatible, inert non-coordinating anions and the use of such catalysts for polymerizing olefins, diolefins and/or acetylenically unsaturated monomers are disclosed.
Abstract:
There is disclosed a method for synthesizing polyolefins having a silyl group at one terminus, the method comprising reacting a monomer of an a-olefin (C.ltoreq.3.ltoreq.10) and a tetrasubstituted silyl radical in the presence of a metallocene catalyst.
Abstract:
New organic light-emitting diodes and related electroluminescent devices and methods for fabrication, using siloxane self-assembly techniques.
Abstract:
An ionic metallocene catalyst for olefin polymerization which comprises: (1) a cyclopentadienyl-type ligand, a Group IVB transition metal, and alkyl, aryl, or hydride substituents, as a cation, and (2) a weakly coordinating anion comprising boron substituted with halogenated, such as tetra fluoro, aryl substituents preferably containing silylalkyl substitution, such as para-silyl t-butyldimethyl.
Abstract:
The organolanthanide hydrides (Cp'.sub.2 LnH).sub.2 (Cp'=.eta..sup.5 -Me.sub.5 C.sub.5 ;Ln=Sm,Lu) rapidly catalyze the copolymerization of methylenecyclopropane and ethylene to cleanly yield high molecular weight polyolefins of microstructure {[CH.sub.2 CH.sub.2 ].sub.x [CH.sub.2 CH.sub.2 C(CH.sub.2)].sub.y }n via sequential olefin insertion and ring-opening/.beta.-alkyl shift processes. Homopolymerization of methylenecyclopropane likewise cleanly yields polymers of the structure [CH.sub.2 CH.sub.2 C(CH.sub.2)].sub.n.
Abstract translation:有机镧系元素氢化物(Cp'2LnH)2(Cp'= eta 5-Me5C5; Ln = Sm,Lu)快速催化亚甲基环丙烷和乙烯的共聚,以清洁地得到高分子量微观结构的聚烯烃{[CH 2 CH 2] x [CH2CH2C )] y} n经由顺序的烯烃插入和开环/β-烷基转移过程。 亚甲基环丙烷的均聚同样干净地得到结构[CH2CH2C(CH2)] n的聚合物。
Abstract:
The regiospecific (1,2-Me.sub.2 C.sub.5 H.sub.3).sub.2 ZrMe.sup.+ MeB(C.sub.6 F.sub.5).sub.3 - mediated ring-opening polymerization of methylenecyclobutane and its copolymerization with ethylene to polyolefins of microstructure --{CH.sub.2 CH.sub.2 CH.sub.2 C(CH.sub.2)]--.sub.n and {--[CH.sub.2 CHR]--.sub.x [CH.sub.2 CH.sub.2 CH.sub.2 C(CH.sub.2)]--.sub.y }.sub.n, respectively is disclosed.