Abstract: Describes polymerizing with actinic radiation a cationically polymerizable organic composition comprising (a) at least one polyfunctional thiirane having at least two groups represented by the following general formula I, 1

Abstract: Describes a polymerizable organic composition comprising a polyol(allyl carbonate), e.g., diethylene glycol bis(allyl carbonate), and from 0.1 percent to 10 percent by weight, based on the total weight of the composition, of an allyl ester terminated nonaromatic polyester, e.g., diallyl 4-methyl-1,2-cyclohexanedicarboxylate oligomer with 1,4-butane diol. Polymerizates prepared from polymerizable organic compositions of the present invention have a refractive index of less than 1.53, e.g., from 1.49 to 1.50, and are substantially free of defects due to tinting failure.

Abstract: Polyurethane foams prepared using polysiloxane/polyoxyalkylene surfactants, preferably blended with a viscosity modifying agent, particularly in combination with particulate silica, especially silica aerogel, exhibit improved thermal insulating capacity, as measured by K-factor, and improved closed cell content, without increasing the density of the polyurethane foam.

Abstract: Describes a polymerizable organic composition comprising at least one polymerizable monomer having at least two ethylenically unsaturated groups, e.g., divinyl benzene, and a polythiol monomer represented by the following general formula, ##STR1## wherein R.sub.1 and R.sub.2 are each selected from the group consisting of straight or branched chain alkylene, e.g., methylene or ethylene, cyclic alkylene, phenylene and C.sub.1 -C.sub.9 alkyl substituted phenylene. Optionally, a monoethylenically unsaturated monomer, e.g., phenoxyethyl methacrylate, and/or an anhydride monomer, e.g., methacrylic anhydride, may also be present. Polymerizates prepared from polymerizable organic compositions of the present invention have a refractive index of at least 1.57, an Abbe number of at least 33 and an initial Barcol hardness of at least 1. Also described are photochromic articles prepared from such compositions.

Abstract: A polymerizable, liquid, substantially gel-free composition comprising a partially polymerized mixture of ethylenically unsaturated compounds wherein: (a) the mixture of ethylenically unsaturated compounds which was partially polymerized comprised a mixture of diethylene glycol (allyl carbonate) compounds each represented by Formula I: ##STR1## in which n is a positive integer, m is a positive integer, and the diethylene glycol (allyl carbonate) compound for which the value of n is 1 constituted from 25 to 75 area percent of the mixture of diethylene glycol (allyl carbonate) compounds; and (b) the ethylenic double bond utilization of the polymerizable, liquid, substantially gel-free composition is at least 3 percent. The polymerizable, liquid, substantially gel-free composition exhibits low shrinkage in the mold when polymerized.

Abstract: Described is a polymerizable organic composition comprising at least one capped polyisocyanate having nonfugitive capping groups, e.g., a 1H-azole, a polythiol having two or more thiol groups, and optionally a reactive hydrogen compound selected from polyols, compounds having both hydroxy and thiol groups, and mixtures thereof. A polymerizate, having a thickness of at least 0.5 millimeters, e.g., an optical lens, obtained from the composition of the present invention has an initial Barcol hardness of at least 1, a refractive index of at least 1.57 and an Abbe number of at least 33. Also described are photochromic articles prepared from such polymerizates.

Abstract: Describes a method of preparing a polymerizate by polymerizing a two-component organic composition comprising: a first component containing a polyfunctional reactant having two or more functional groups selected from isocyanate, isothiocyanate and combinations of isocyanate and isothiocyanate groups; and a second component containing a polythiol represented by the following general formula I, ##STR1## wherein R.sub.1 and R.sub.2 are each selected from the group consisting of straight or branched chain alkylene, e.g., methylene and ethylene, cyclic alkylene, phenylene and C.sub.1 -C.sub.9 alkyl substituted phenylene. The second component may also optionally contain a reactive hydrogen compound that is different than the polythiol of general formula I. Polymerizates prepared according to the present invention are useful as ophthalmic lenses and have a refractive index of at least 1.57, an Abbe number of at least 33 and an initial Barcol hardness of at least 1.

Abstract: Describes a polymerizable organic composition comprising an aromatic monomer having at least two vinyl groups, e.g., divinyl benzene, a polythiol monomer having at least two thiol groups, e.g., pentaerythritol tetrakis(2-mercaptoacetate), and an anhydride monomer having at least one ethylenically unsaturated group, e.g., methacrylic anhydride. Polymerizable compositions according to the present invention, may optionally further comprise a polymerizable comonomer having at least two (meth)acryloyl groups, e.g., pentaerythritol tetrakis (acrylate). Polymerizates prepared from polymerizable organic compositions of the present invention have a refractive index of at least 1.57 and an Abbe number of at least 33. Also described are photochromic articles prepared from such compositions.

Abstract: A composition comprising a particulate dispersion of from 50% to 98.9% by weight of a siloxane-polyoxyalkylene copolymer surfactant, from 1% to 49.9% by weight of a nonionic organic surfactant other than the siloxane-polyoxyalkylene copolymer surfactant and from 0.1% to 25% by weight, based on the total weight of the composition, of a particulate material having a particle size of less than 20 microns, is described. A method of preparing such a composition, and polyurethane and polyisocyanurate foams containing such a composition are also described. The nonionic organic surfactant is preferably an ethoxylated nonylphenol. The particulate material is preferably a hydrophobic precipitated silica. The composition of the invention is useful as an additive in the preparation of rigid polyurethane and polyisocyanurate foams.

Abstract: Liquid comprising from 93 to 100 percent by weight alcohol is removed from silica alcogel at subcritical temperature to produce silica aerogel. The silica aerogel produced by the method of the present invention not only has high porosity, but in most instances it also has a narrow distribution of small pore sizes. The silica aerogel is preferably reduced in size so as to form particulate silica aerogel.

Abstract: A composition comprising a particulate dispersion of from 50% to 98.9% by weight of a siloxane-polyoxyalkylene copolymer surfactant, from 1% to 49.9% by weight of a nonionic organic surfactant other than the siloxane-polyoxyalkylene copolymer surfactant and from 0.1% to 25% by weight, based on the total weight of the composition, of a particulate material having a particle size of less than 20 microns, is described. A method of preparing such a composition, and polyurethane and polyisocyanurate foams containing such a composition are also described. The nonionic organic surfactant is preferably an ethoxylated nonylphenol. The particulate material is preferably a hydrophobic precipitated silica. The composition of the invention is useful as an additive in the preparation of rigid polyurethane and polyisocyanurate foams.