Abstract: During radiotherapy for malignant conditions, healthy tissues can suffer from radiation damage. Traditional radiation shields designed to protect healthy tissues are prepared by a lengthy, multi-step complex procedure. Materials are described for preparation of a radiation shield for use during radiation therapy, especially therapy of the head and neck, where the material comprises a composite of non-radioactive, non-toxic high atomic density metal or metal alloy spherical particles dispersed in a manually moldable elastomeric material. Custom radiation shields are formulated of this material without the need for use of impressions or molds. Healthy tissues may then be shielded during radiation therapy by positioning the custom-fitted radiation shield in the desired location on the patient's body.

Abstract: A microwave radiation absorbing adhesive comprises dissipative particles bound in a thermoplastic or thermosetting adhesive. The absorbing adhesive may be applied directly to the surface of any object, or to an irregularly shaped object, or into cracks or crevices in or between objects, including conventional absorbers. Several types of dissipative particles and adhesives may be used.

Abstract: A composite filler material is disclosed. The filler material includes an inorganic core and a layer of crosslinked silicone elastomer covering the core and chemically bonded to the core. A process for making the composite filler material is also disclosed.

Abstract: A room temperature curable organopolysiloxane composition comprising a diorganopolysiloxane having a hydroxyl group or alkoxy groups, a filler, a particular alkoxysilane, an organosilicon compound having a particular guanidinyl group, and an organic tin compound, and further comprising an organosilicon compound having at least one group represented by the general formula: ##STR1## where R.sup.4 is a substituted or unsubstituted monovalent hydrocarbon group, or a substituted or unsubstituted phenyl group, R.sup.5 and R.sup.6 are each a hydrogen atom, methyl or ethyl group, and n is an integer of 0, 1 or 2. By virtue of the last component, the composition exhibits markedly good storage stability.

Abstract: A method of sizing insulating glass fibers, comprising: preparing glass fibers by a high temperature aerodynamic procedure in which glass fibers are drawn out by a gas current and collected in a hood; spraying a size diluted in water onto said glass fibers in said collection hood, said size consisting essentially of an epoxy resin, an amino hardening agent and, as additives, 0.1 to 2.0% of a silane and 0 to 15% of a mineral oil, each calculated on 100 parts of dry resin, wherein said epoxy resin is a condensation product of epichlorohydrin and bisphenol A having a polymerization index n of less than 1 and the equivalent molar mass of the hardening agent is less than 100 g and said size is free of formaldehyde and components which release formaldehyde when baked; and recovering a sized insulating glass fiber product.

Abstract: Polydiorganosiloxane/thiuram disulfide block copolymers having the formula: ##STR1## well adapted as "polyiniferters" in the radical polymerization of vinyl monomers, e.g., the (meth)acrylates or styrene, are prepared by reacting a corresponding .alpha.,.omega.-(amino)diorganopolysiloxane with CS.sub.2 in the presence of a tertiary amine and an oxidizing agent, e.g., iodine.

Abstract: An organopolysiloxane/acrylate ester copolymer emulsion composition is prepared by forming a water-based emulsion of an alkenyl-containing organopolysiloxane containing no more than 5,000 parts per million of organosiloxane oligomer which has .ltoreq.20 silicon atoms in its molecule and copolymerizing the emulsion with an acrylate ester monomer. The resultant copolymer does not suffer from disadvantages of prior art systems, such as staining in applications as a paint or water repellent, staining in fiber treatment applications, or reduction of adhesion when the copolymer is used as a release coating.

Abstract: This invention is directed to a composition comprising (A) a continuous phase of (i) a crosslinked organosilicon polymer or crosslinkable organosilicon prepolymer comprising alternating (a) cyclic polysiloxane or tetrahedral siloxysilane residues and (b) polycyclic hydrocarbon residues derived from polycyclic polyenes having at least two non-aromatic, non-conjugated carbon-carbon double bonds in their rings linked through carbon to silicon bonds, wherein at least one of the cyclic polysiloxanes or tetrahedral siloxysilanes (a) or the polycyclic polyenes (b) used to form the polymer or prepolymer has more than two reactive sites; or (ii) a crosslinked or crosslinkable linear poly(organohydrosiloxane) polymer having at least 30% of its .tbd.

Abstract: A fluorinated polydiorganosiloxane elastomer having improved physical properties can be obtained through the use of a method which first reacts a hydroxyl endblocked trifluoropropylmethylsiloxane having a Williams Plasticity Number of greater than 225 with a methylvinyldi(N-alkylacetamido)silane to give a chain extended polymer having pendant vinyl groups only at the location of the chain extension. The polymer is then reinforced with fume silica and compounded into a stock. The cured stock has improved tensile strength and tear strength when compared to similar compositions which do not contain the same type of polymer. The polymer has pendant vinyl groups located along the polymer chain, with the distance between them being relatively large. When too many vinyl pendent groups are present along the chain, the improved results are not obtained.

Abstract: A silicone composition containing a carboxylic acid amide which develops a vapor pressure during its use in an electrical device prevents faulty conduction at electrical contacts which are caused by silicone vapor. Electrical devices made by bringing the vapor of the carboxylic acid in the presence of the silicone vapor exhibit extended useful lives.

Abstract: A fine powder of an epoxy-containing silicone elastomer can be made by:(i) dispersing in water a hardenable organopolysiloxane compound composed of(A) an organopolysiloxane of 20-100,000 cS at 25.degree. ##STR1## (R's are the same or different unsubstituted or substituted hydrocarbon groups containing no unsaturated bond; subscripts a and b are integers selected from 0, 1, 2 and 3 such that a+b=3; x is a positive integer; y is 0 or a positive integer such that 2b+y.gtoreq.2);(B) an organohydrogenpolysiloxane containing, in a molecule, at least two hydrogen atoms bonded to silicon and at least one epoxy-bearing organic group bonded to silicon ##EQU1## (R is the same as above; A is an epoxy-bearing organic group; c is a number from 0 to 3, and d and e are numbers from 0.005 to 2.0 such that 0.8<c+d+e<3);(C) a Pt-containing catalyst;(ii) hardening the particles dispersed in the aqueous emulsion to thereby obtain a silicone elastomer emulsion of particles having a mean diameter of 20 .mu.

Abstract: Polyester/silicon co-crosslinked polymer substrates at least partially degradable by hydrolysis, well adopted as matrices for the controlled release of a wide variety of active agents therefrom, are prepared by controlledly co-crosslinking (a) at least one diorganopolysiloxane having at least two hydroxyl groups per molecule and (b) an oligomeric polylactic and/or polyglycolic polyester .alpha.,.omega.-diol, with an effective co-crosslinking amount of (c) an organic polyisocyanate.

Abstract: A method for making an epoxyfunctional organosilicon compound is provided, comprising the step of reacting at a temperature of from about 25.degree. to about 100.degree. C. a mixture comprising (A) an ethylenically unsaturated epoxide; (B) an organohydrogenpolysiloxane or organohydrogensilane; and (C) a rhodium complex catalyst selected from the group consisting of:(i) RhX.sub.3 (SR.sub.2).sub.3 ;(ii) RhX.sub.3 .multidot.xH.sub.2 O;(iii) [RhX(norbornadiene)].sub.2 ;(iv) RhX(CO)(R.sub.3 P).sub.3 ;(v) RhX(R.sub.3 P).sub.3 ; and(vi) [RhCl(cyclooctadiene)].sub.2 ;wherein X is a halogen atom, x is a number equal to 3 or 4, and R is an alkyl radical having from 1 to 8 inclusive carbon atoms, aryl, aralkyl, or alkaryl radical or the R.sub.3.sup.1 SiQ-- group in which Q represents a divalent aliphatic hydrocarbon radical having from 1 to 6 inclusive carbon atoms and R.sup.1 represents an alkyl radical having from 1 to 8 inclusive carbon atoms, aryl, aralkyl, or alkaryl radical or a (CH.sub.3).sub.3 Si-- radical.

Abstract: The polymeric ingredient of the inventive rubber composition is an acrylic polymer modified with a mercapto-containing organopolysiloxane as prepared by the emulsion polymerization of an acrylic monomer in an aqueous emulsion of the organopolysiloxane. Characteristically, the acrylic monomer is copolymerized with another monomer having an active halogen atom or an epoxy group. By virtue of this unique formulation of the rubbery polymer, the inventive rubber composition prepared by compounding the rubbery polymer with a reinforcing filler and a specified curing or crosslinking agent can be vulcanized to give a vulcanizate having excellent mechanical properties, heat resistance, oil resistance and cold resistance as a combination of the features of silicone rubbers and acrylic rubbers.

Abstract: An improved aqueous silicone emulsion which cures to a reinforced elastomer upon removal of water is obtained through the use of an anionic, stable dispersion of fumed silica in water as the source of reinforcing silica. The fumed silica dispersion is combined with an aqueous, anionic emulsion of crosslinkable polydiorganosiloxane and a crosslinking system.

Abstract: Hot-melt silicone pressure sensitive adhesive compositions, methods of using the compositions, articles made using the compositions, and methods of making articles using the compositions. The hot-melt silicone pressure sensitive adhesive compositions include a mixture of (i) a silicone resin, (ii) a polyolimethylsiloxane fluid, and (iii) from about 0.5 to about 20 weight percent, based on the total weight of the silicone resin and the polydimethylsiloxane fluid, of a polyphenylmethylsiloxane fluid having a viscosity at 25.degree. C. of from about 5 to about 60,000 centistokes so that the adhesive will be in a generally flowing state at temperatures above about 100.degree. C., as well as being capable of transdermal drug delivery.

Abstract: This invention relates to an aromatic vinyl ether siloxane having the formula ##STR1## wherein A is --CH.sub.2 -- or >C(CH.sub.3).sub.2 ;m has a value of from 1 to 22;R.sub.1 and R.sub.2 are each selected from the group consisting of ##STR2## with the proviso that at least one of R.sub.1 and R.sub.2 is (a) and R.sub.2 can be a mixture of (a) and (b) when m is greater than one,R.sub.3 and R.sub.4 are lower alkyl,r has a value of from 0 to 20,R is alkylene or alkylene phenylene,B is C.sub.2 to C.sub.20 alkylene, arylene or a fluorinated derivative of these radicals,t has a value of from 1 to 100,Z is C.sub.2 to C.sub.3 alkylene andn has a value of from 1 to 10.

Abstract: The present invention is directed to silicone polyurethane copolymers containing phosphorescent dye compounds wherein the copolymers are represented by the formula: ##STR1## wherein n is an integer ranging from 1 to about 30, and y, z, and w are integers ranging from 0 to about 40, wherein one of y, z, and w is at least one; and A is a diamide, B is a silicone block copolymer, D is a chain extender, and E is a phosphorescent porphyrin-type compound.

Abstract: Improved polyphthalamide compositions, particularly for injection molding applications, comprise a polyphthalamide component with at least two recurring units selected from terephthalamide, isophthalamide and adipamide units and having high heat deflection temperature when filled with glass fibers; reinforcing fibers; and effective amounts of particulate talc. Molded articles prepared from such compositions exhibit excellent mechanical and thermal properties, including high heat deflection temperature, even when molded using molds heated below Tg of the polyphthalamide component, often facilitating molding using steam or hot water-heated molds.

Abstract: Storage stable and gel-free organosiloxane compositions in the form of flowable powders are prepared by blending a high consistency polydiorganosiloxane into a quantity of fluidized reinforcing filler that is heated to a temperature of from 100.degree. to 200.degree. C. prior to or immediately following introduction of the polydiorganosiloxane. When silica is the reinforcing filler, the filler is typically treated with an anti-creping agent either prior to or during this blending process. The resultant mixture is heated while being subjected to shearing forces that reduce its average particle size to achieve a flowable powder.