Abstract: An apparatus for charging fibers that contain a nonconductive polymer. A polar liquid 32, 34 is sprayed onto free-fibers 24, and the free-fibers 24 are then collected to form an entangled nonwoven fibrous web 25 that may contain a portion of the polar liquid. The nonwoven web 25 is then dried 38. By applying an effective amount of polar liquid 32, 34 onto the nonconductive free-fibers 24 before forming the nonwoven web 25, followed by drying 38, the individual fibers 24 become charged. The apparatus can enable the fibers 24 to be charged during web manufacture without subsequent processing.

Abstract: A method and apparatus for charging fibers that contain a nonconductive polymer. A polar liquid 32, 34 is sprayed onto free-fibers 24, and the free-fibers 24 are then collected to form an entangled nonwoven fibrous web 25 that may contain a portion of the polar liquid. The nonwoven web 25 is then dried 38. By applying an effective amount of polar liquid 32, 34 onto the nonconductive free-fibers 24 before forming the nonwoven web 25, followed by drying 38, the individual fibers 24 become charged. The method and apparatus enable the fibers 24 to be charged during web manufacture without subsequent processing.

Abstract: A compound comprising wherein R2 is an alkyl group which may be straight chain or branched and n is a number of from 2 to 40.

Abstract: A high efficiency filtration medium comprised of a nonwoven filter web of electret charged fibers of a nonconductive thermoplastic resin having a resistivity greater than 10.sup.14 ohm-cm, preferably polypropylene. The nonwoven filter web has a basis weight (BW) of less than 60 grams/m.sup.2, an effective fiber diameter (EFD) of less than 5 microns and a penetration (PEN) of less than 0.03%, wherein the ratio);BW/(EFD.PEN)is greater than 200. The invention filter medium can be easily used in applications requiring HEPA performance at relatively low pressure drops.

Abstract: An electret filter media, and mask, that is made of a nonwoven web of thermoplastic microfibers. The thermoplastic microfibers are of substantially the same composition, are nonconductive, and have an effective fiber diameter less than about 15 micrometers. The nonwoven web also has sufficient unpolarized trapped charge to exhibit an initial filtration quality factor of at least 0.31 when measured under the DOP Penetration and Pressure Drop Test.

Abstract: A compound comprising ##STR1## wherein R.sub.f is a perfluorinated moiety which may contain one or more catenary ether oxygen atoms, Q is a linking group selected from alkylene groups having 1 or 2 carbon atoms, sulfonamido groups or combinations thereof, and R.sup.1 is a perfluoroalkyl group.

Abstract: Electret filter media comprising a fibrous web of a blend of a thermoplastic resin and at least one compound or oligomer that enhances the web's electret properties.

Abstract: Fibrous webs comprising a blend of a thermoplastic resin and at least one compound or oligomer which is ##STR1## wherein R.sub.f is a perfluorinated moiety which may contain one or more catenary ether oxygen atoms, Q is a linking group selected from alkylene groups having 1 or 2 carbon atoms, sulfonamido groups or combinations thereof, R is an alkyl group, R.sup.1 is a perfluoroalkyl group, R.sup.2 is an alkyl group which may be straight chain or branched and n is a number of from 2 to 40.

Abstract: A composition comprising a blend of a thermoplastic resin and at least one compound or oligomer which is ##STR1## wherein R.sub.f is a perfluorinated moiety which may contain one or more catenary ether oxygen atoms, Q is a linking group selected from alkylene groups having 1 or 2 carbon atoms, sulfonamido groups or combinations thereof, R is an alkyl group, R.sup.1 is a perfluoroalkyl group, R.sup.2 is an alkyl group which may be straight chain or branched and n is a number of from 2 to 40.

Abstract: The present invention relates to a method of making a fibrous electret material which includes the steps of (1) forming a fibrous web of nonconductive thermoplastic fibers from a blend of nonconductive thermoplastic resin and an additive which is (a) a thermally stable organic compound or oligomer containing at least one perfluorinated moiety or (b) a thermally stable organic triazine compound or oligomer containing at least one nitrogen atom in addition to those in the triazine group or (c) a combination thereof; (2) impinging jets of water or a stream of water droplets onto the web at a pressure sufficient to provide the web with filtration enhancing electret charge; and (3) drying the web.

Abstract: A method of charging a nonwoven web of thermoplastic microfibers to provide electret filter media is provided. The method includes impinging on a nonwoven web of thermoplastic nonconductive microfibers capable of having a high quantity of trapped charge jets of water or a stream of water droplets at a pressure sufficient to provide the web with filtration enhancing electret charge and drying said web.

Abstract: A method of manufacturing an electro-conductive elastomeric material comprises mixing together silicone polymer gum, graphitic carbon particles, curing and cross-linking agents in the presence of an oil having a carbon chain length of at least 16 and having a high degree of mesogenicity, together with a volatile additive in which the oil and gum dissolve and/or disperse miscibly. The volatile additive may be Toluene, Chloroform, Tetrahydrofuran, n-Hexane or SBP3.

Abstract: An elastomeric electro-conductive device (10) capable of providing within a predetermined range of elastic elongation (.lambda.) of the device (10) sensory signals representative of elastic elongation (.lambda.) imposed on the device includes an elastomeric electro-conductive member (11) bonded to an elastomeric substrate (12). Member (11) and substrate (12) have substantially similar resistance-to-stretch characteristics .phi. within the predetermined range. On a Mooney Plot for (.lambda..sup.-1) values in the range 0.5 to 0.8 .phi. is substantially constant at 0.4 M Nm.sup.-2.

Abstract: A method of manufacturing an electro-conductive elastomeric material comprises the steps of mixing together a silicone polymer gum such as type C2501, graphitic carbon particles such as 55 micron particle size, a curing agent such as Silester O.S., and a cross-linking agent such as DBTL in the presence of a mesogenic oil which is synthetic, unsaturated, and has two oleic chains. The preferred oil is di-oleyl-oxalate.

Abstract: An elastomeric electro-conductive device 10 for human/animal joint movement monitoring comprises a silicone polymer non-conductive substrate 11 carrying an elastomeric electro-conductive member 12 formed from silicone polymer loaded with graphite carbon particles. Conductor means 14A,14B enable connection of the device 10 to an electrical network and comprise lengths 15 of conductive silicone rubber adhesively secured at one end to member 12 by a body 18 of elastomeric bonding material. The body 18 and the member 12 have the same electrical characteristics and may have identical constituents and formulations.