Abstract: A process for manufacturing high molecular weight polysiloxane copolymers by interfacial polymerization. The polysiloxanes may contain phenylmethyl siloxane blocks and dimethyl siloxane blocks, alternately polymerized together to form an (A.sub.m B.sub.n).sub.x type copolymer. The interfacial polymerization process is fast, proceeds smoothly at room temperature, and is not reversible, i.e., no cyclic siloxane species are generated. The polysiloxanes can be formed as thermoplastic elastomers suitable for use as sealants, fillers, and films.

Abstract: An interfacial polymerization process wherein organosilicon reactants are dissolved in mutually immiscible, nonaqueous solvents, and a condensation product is formed at the interface. This technique has many of the advantages of analogous organic interfacial polymerization, and may be used, for example, to prepare crosslinked films, fibers, particles, or encapsulants. Structures which cannot be prepared by other routes can be made. In particular, a well-defined alternating dimethyl/diphenyl siloxane block copolymer can be prepared by condensing a dihalo organosilicon compound such as diphenyldichlorosilane (C.sub.6 H.sub.5).sub.2 SiCl.sub.2 in diphenyl ether with a dimethyl silanolate in cyclohexane. The advantages are ability to control polymer structure, and there is no rearrangement during polymerization.

Abstract: A process of manufacturing elastomeric fibers in which fibers are obtained by co-extruding an extrudable and curable .tbd.SiO-- containing material and an aqueous organic polymer solution into a coagulation bath. The .tbd.SiO-- containing material is surrounded by the coagulated organic polymer. The .tbd.SiO-- containing material is then cured inside the protective sheath that is formed, and thereafter the organic polymer sheath is dissolved to expose a continuous elastomeric fiber of the .tbd.SiO-- material.

Abstract: A method for stabilizing a mixture comprising polydiorganosiloxane and an alkali metal. The method comprises contacting a silyl phosphonate described by formula R.sup.1.sub.a (OH).sub.b (OSiR.sup.2.sub.3).sub.3-a-b P.dbd.O, where each R.sup.1 and R.sup.2 is an independently selected hydrocarbyl radical comprising less than about twelve carbon atoms, a=1 or 2, b=0 or 1, and a+b=1 or 2, with a polydiorganosiloxane and an alkali metal.

Abstract: This invention provides reinforced composite structures consisting essentially of a matrix and a dispersed phase, where the matrix is a hydrogel containing water and a solubilized vinyl alcohol homopolymer, the dispersed phase contains a plurality of uniformly distributed acicular regions consisting of fibrils formed from a highly oriented crystalline vinyl alcohol polymer, where the diameter of the said fibrils is less than 1 millimeter, the aspect ratio of the fibrils is from 2:1 to 1000:1, and where the composite is characterized by a gradual transition in the degree of crystallinity at the interfaces between the matrix and the fibrils.

Abstract: This invention provides reinforced composite structures consisting essentially of a matrix and a dispersed phase, where the matrix is a hydrogel containing water and a solubilized vinyl alcohol homopolymer, the dispersed phase contains a plurality of uniformly distributed acicular regions consisting of fibrils formed from a highly oriented crystalline vinyl alcohol polymer, where the diameter of the said fibrils is less than 1 millimeter, the aspect ratio of the fibrils is from 2:1 to 1000:1, and where the composite is characterized by a gradual transition in the degree of crystallinity at the interfaces between the matrix and the fibrils.

Abstract: This invention relates to hollow elongate articles such as tubing and fibers formed from non-crosslinked polyvinyl alcohol. The articles are prepared by extruding a solution of polyvinyl alcohol in the shape of the desired article into a coagulating bath concurrently with a stream of a non-solvent for the polymer. The stream occupies the area corresponding to the interior cavity of the article and prevents collapse of the cavity until the article has solidified in the coagulation bath.

Abstract: A composition, used to control foaming in non-aqueous systems consisting essentially of (A) a foam control agent for non-aqueous systems that is not readily soluble in the non-aqueous systems, (B) a dispersing agent, and (C) a non-ionic surfactant having an HLB number greater than 10, is disclosed.