Abstract: Pipe couplings are formed by consolidation of a polymer into braided fibre reinforcement by recovery of a heat-recoverable driver thereover. A liner, e.g. of non-cross-linked polyvinylidene fluoride, may be used, preferably with three layers of polymer/braid, to achieve a Freon-tight seal for coupling loosely swaged or butt-jointed refrigerator pipes. Braids carrying a consolidatable polymer which allows the braid crossover points to slip freely during recovery of the driver are preferred for optimum performance.

Abstract: A process for producing an aromatic polyketone which comprises polymerizing an appropriate monomer or monomers by a Friedel-Crafts polymerization reaction using a Lewis acid catalyst. A controlling agent such as a Lewis base may be added to the reaction medium and/or the reaction is conducted under specified conditions to control the reaction. The reaction medium comprises, for example, aluminum trichloride as the Lewis acid, an organic Lewis base such as N,N-dimethylformamide or an inorganic Lewis base such as sodium or lithium chloride, and a diluent such as methylene chloride or dichloroethane. The amount of Lewis acid, the amount of Lewis base, the temperature of the reaction and the monomer to diluent molar ratio are varied depending on the monomer system to obtain melt-processable, high molecular weight, substantially linear polymers, for example poly(carbonyl-p-phenylene-oxy-p-phenylene), poly(carbonyl-p-phenylene-oxy-p-phenylene-oxy-p-phenylene), and the like.

Abstract: A dimensionally recoverable article, preferably a heat-recoverable article, has on at least part of a surface thereof an adhesive composition that will cure by reaction of a plurality of mutually reactive components. The components are in the form of particles which are mixed together and which will fuse when heated. Preferred adhesives are based on combinations of an epoxy with a polyamide, carboxylic acid, phenolic resin or blocked isocyanate curing agent.The particulate adhesives show a synergistic increase in rate and/or level of cure when used in conjunction with a recoverable article.

Abstract: The preparation of poly(arylene ether ketones) by Friedel-Crafts polymerization, in the presence of a Lewis acid catalyst and a diluent, is conducted under conditions in which the polymer and/or its complex with the catalyst is suspended in the diluent during at least part of the polyreaction mixture if desired. The dispersant may be a polymer or an organic compound containing at least eight carbon atoms and is preferably a Lewis base. The dispersant preferably contains at least one molecular segment substantially compatible with the poly(arylene ether ketone) or its complex with the Lewis acid and substantially incompatible with the diluent and at least one molecular segment substantially compatible with the diluent and substantially incompatible with the poly(arylene ether ketone) or its complex with the Lewis acid.

Abstract: A method of purifying an aromatic carboxylic acid halide, for example p-phenoxybenzoyl chloride, comprising the steps of: (a) adding an acidic catalyst, for example a molecular sieve, to the acid halide; (b) heating the resulting mixture of the acidic catalyst and the acid halide to a temperature of about 180.degree. C. to about 250.degree. C. for a period of at least 0.5 hours; (c) distilling the mixture to obtain acid halide substantially free of aldehyde and the halo derivative thereof. Optionally, a reactive aromatic compound may be added to the mixture of the acid halide and the acidic catalyst before the heating step. The process is particularly useful for providing aromatic acid halides of sufficient purity for preparing melt stable aromatic polyketones.

Abstract: A heat-recoverable soldering device comprises a heat-recoverable member having a fusible solder insert and associated with the solder insert, a solder flux composition which undergoes a visible color change at a critical temperature. Solderable substrates are positioned within the device and heated until a critical temperature has been reached as indicated by a color change in the flux. The critical temperature depends on the material of the particular heat-recoverable member and the solder used. It is that temperature which is required to effect a solder joint between the substrates and recovery of the heat-recoverable member. Novel flux compositions and their use in soldering are also disclosed.

Abstract: A piezoelectric device comprising a first conductor, a conductive polymer member which contacts the first conductor, a piezoelectric polymer member which contacts the conductive polymer member but which is separated from the first conductor and which has been rendered piezoelectric by stretching and polarizing it while it is in contact with the conductive polymer member, and a second conductor which contacts the piezoelectric polymer member but which is separated from both the conductive polymer and the first conductor.

Abstract: A heat activatable sealing piston comprising a cylinder of polymeric material radially expandable on application of heat. The piston can be incorporated into thermal actuators of various types. In a preferred embodiment, the sealing piston is used in an electrical connector, together with a gas generating means to force solder between an electrical conductor inserted into the connector and the walls of the tubular connector.

Abstract: The invention relates to novel laminate tubular articles comprising an outer layer having a modulus of at least about 10.sup.7 Pascals, an interior layer comprising a polymeric material having a loss tangent of at least about 0.5 at a temperature of from about 0.degree. C. to about 40.degree. C. at a frequency of from 10-4,000 Hz and whose modulus is less than the modulus of the outer layer and an innermost layer having a modulus greater than the modulus of said interior layer. The invention further relates to a device for sensing in a body of water, said device comprising at least one sensor surrounded by the novel laminate tubular articles of the invention. The mechanical and acoustic properties of the article make it particularly appropriate for use as the hose in a towed-array sonar system.

Abstract: A protected electrode article comprising sensitive electrode material having a layer of protective material bonded to at least part of its surface by means of an adhesive which can be made to swell by treatment with liquid, so as to increase the permeability of the adhesive to electrolyte which is encountered by the protected electrode material when incorporated in an electrochemical device.

Abstract: A heat-recoverable soldering device comprises a heat-recoverable member containing a fusible solder insert, solder flux and a thermochromic composition which undergoes a visible change from a colored to a colorless state at the soldering temperature. Solderable substrates are positioned within the device and heat is applied until the soldering temperature has been reached, as indicated by a color change of the thermochromic composition. The soldering temperature is that temperature which is required to effect a solder joint between the substrates and recovery of the heat-recoverable member. Typically this temperature is at least about 20.degree. C. above the melting temperature of the solder.

Abstract: An article comprising vinylidene fluoride polymer which has been rendered piezoelectric by stretching the article to a final draw ratio of less than about 6:1 and polarizing and has an equivalent activity A* of at least 6, where A* is given byA*=d.sub.3h -50(d.sub.o -d)where d.sub.3h is the hydrostatic coefficient of the stretched and polarized vinylidene fluoride polymer after heating at 120.degree. C. for 1 hr, in units of pC/N; d.sub.o is the density of the unstretched and unpolarized polymer, in units of g/cc; and d is the density of the stretched and polarized polymer before heating at 120.degree. C. for 1 hr, in units of g/cc, said article having an aggregate dimensional change of less than 15% upon heating at 120.degree. C. for 1 hr, as measured by the sum of the absolute dimensional changes along three orthogonal coordinate axes, one of which is a principal direction of stretching.

Abstract: The preparation of poly(arylene ketones) and in particular all para-linked poly(arylene ether ketones) by Friedel-Crafts polymerization in the presence of a Lewis acid generally results in an intractible reaction product difficult to remove from the reaction vessel and difficult to purify. The addition of a liquefaction agent, such as a hydrogen halide and in particular hydrogen chloride, to the reaction mixture, results in a tractible gel or a liquid which can be readily handled. The hydrogen halide is preferably under pressure and a diluent may also be added along with the hydrogen halide.

Abstract: A single-phase ground enclosed load break switch for distribution voltages has a hermetically sealed cylindrical metal housing of from 2 to 6 inches diameter which contains an insulating gas under pressure. The switch has a movable contact assembly to contact a pair of opposed stationary coaxial conductors within the housing. Movement of the contact assembly along one conductor breaks the connection with the other conductor and simultaneously reduces the sliding contact force on the first conductor. The switch has conductive bands coaxially positioned near the housing around the conductors for low voltage measurements monitoring conductor energization and contact position. A rocking bellows at the fulcrum of a crank actuator provides a compact hermetic seal for the actuator without excessive strain of the bellows. A safety interlock with a visual indicator locks the contact assembly in case of a loss of pressure.

Abstract: Polymeric cladding for elongate substrates, preferably electrical conductors, comprises an inner layer and an outer layer, the outer layer being a cross-linked polymer composition filled with halogen-free particulate inorganic flame-retardant filler which has been treated with material which increases the elongation to break of the composition at 200.degree. C. to at least 50%. The enhanced elongation enables the cladding better to resist burning, possibly by reducing the tendency for the outer layer to split when exposed to fire. Bundles of insulated electrical wires may be wrapped in mineral tape, preferably mica tape, to provide circuit integrity cables which are significantly smaller and/or lighter than previously known.

Abstract: A shrinkable tubular article comprises a tubular inner elastomeric member held in a radially expanded configuration by a tubular outer restraining means. The restraining means is prepared from a blend of a relatively rigid thermoplastic material and a segmented copolymer having at least one segment compatible with the thermoplastic and at least one segment compatible with the elastomer of the inner member. Optionally, the restraining means contains a tackifier. The inner surface of the outer member and the outer surface of the inner member are directly bonded together (i.e. without an interfacial adhesive). The bond between the members is sufficiently strong to restrain the inner elastomer member from shrinking to, or toward, its unexpanded configuration. In addition, the bond weakens sufficiently on application of solvent to permit the elastomeric member to peel away from the restraining outer member.

Abstract: An apparatus for measuring the moisture content of soil includes a chamber having a water-swellable material in the chamber, the chamber being sized so that the water-swellable material can swell to its fully swollen state, with the external resistance, if any, against the swelling being substantially constant. The device includes a device for transmitting water to the water-swellable material so that it is in equilibrium with the environment. A sensor responsive to the volume of the water-swellable material is provided to indicate the water content of the environment exterior of the apparatus. The preferred sensor is a magnet moveable by the water-swellable material and a Hall effect sensing device.

Abstract: A tubular heat recoverable article has two layers in thermal contact, one inside the other. The two layers have appreciably different recovery temperatures. Shrinking of the article on to a substrate is effected by applying heat to the outer layer (1) of higher recovery temperature such that conduction to the inner layer (2) of lower recovery temperature ensures that the inner layer (2) reaches its recovery temperature, and thus becomes elastomeric, before the outer layer begins to recover. The article, which may be used in an electric power cable splice, thus combines good storage life with good recovery time.

Abstract: This invention relates to the mechanical and environmental protection of cable joints, especially in power or other current-carrying cables. Disclosed is a recoverable sleeve which conforms closely to the cable joint, and a non-profiled liner which bridges the joint and comprises a plurality of elongate elements assembled into a sheet. Flexible means is provided for holding the elements in a side-by-side arrangement and allowing the separation between the elements to vary to allow the liner to conform to the profile of the cable joint. Such flexible means may extend across the element and provide a water vapor barrier. Disclosed also is a method of protecting a cable joint utilizing the sleeve and liner. Where the cables to be jointed have metal armor, screen and/or shielding, the elements may be fabricated from metal or metal alloy and may then provide both armoring and a fault current path across the joint.

Abstract: A single-phase ground enclosed load break switch for distribution voltages has a hermetically sealed cylindrical metal housing of from 2 to 6 inches diameter which contains an insulating gas under pressure. The switch has a movable contact assembly to contact a pair of opposed stationary coaxial conductors within the housing. A rocking bellows at the fulcrum of a crank actuator provides a compact hermetic seal for the actuator without excessive strain of the bellows. A safety interlock with a visual indicator locks the contact assembly in case of a loss of pressure. Excessive pressure in the switch causes the bellows to be punctured with consequent locking of the contact assembly. The switch is small enough to be mounted directly on a transformer or placed into a cable, without the need for a separate enclosure.