Ppg Industries, Inc.

Thomas A Rechlicz

Dennis D Leatherman

Richard A Schwarz

Harlan B Johnson

William A Williams

Bernard A Maloney

Paul L Benenati

Barbara J Anderson

The tendency of microporous material to discolor over a period of time when exposed to the atmosphere during normal usage can be reduced if the microporous material comprises whiteness retaining organic surface active agent.

Microporous material exhibiting increased whiteness retention

A coated article comprises a substantially continuous, moisture vapor permeable coating of hydrophobic polymer joined to one side of a sheet of microporous material comprises a matrix consisting essentially of linear ultrahigh molecular weight polyolefin, a large proportion of finely divided, water-insoluble siliceous filler, and interconnecting pores.

Microporous material having a coating of hydrophobic polymer

A multilayer article comprises at least one layer of substantially porous material bonded to at least one layer of microporous material comprising a matrix consisting essentially of linear ultrahigh molecular weight polyolefin, a large proportion of finely divided, water-insoluble siliceous filler, and interconnecting pores. The microporous material has regions of stretch-induced molecularly oriented polymer in the matrix.

Multilayer article of microporous and porous materials

Disclosed is a method of preparing a cathode-diaphragm assembly for an electrolytic cell, where the diaphragm is adherent, e.g., to itself and to the cathode. The cathode-diaphragm unit is prepared by first depositing a protective film on the catalytic cathode, and thereafter depositing the diaphragm material under such conditions that the diaphragm material becomes self-adhereing and conforms to the cathode but is spaced from the cathode. In this way the diaphragm is subsequently removable without damage to the cathode catalyst.

Method of depositing an asbestos diaphragm and the diaphragm prepared

Disclosed is a method of preparing a cathode-diaphragm assembly for an electrolytic cell, where the diaphragm is adherent, e.g., to itself and to the cathode. The cathode-diaphragm unit is prepared by first depositing a protective film on the catalytic cathode, and thereafter depositing the diaphragm material under such conditions that the diaphragm material becomes self-adhering and conforms to the cathode but is spaced from the cathode. In this way the diaphragm is subsequently removable without damage to the cathode catalyst.

Method of operating an electrolytic cell

Disclosed is a method of forming a cathode by electroplating a sacrificial metal and a catalytic metal from an electroplating solution onto an electroconductive substrate. Initial electrodeposition is carried out at a high temperature to preferentially electroplate the catalytic metal, the electroplating solution is then cooled, and thereafter the electrodeposition is carried out at a lower temperature to codeposit sacrificial metal and catalytic metal. Also disclosed is an electrode prepared thereby.

Method of preparing a cathode by high and low temperature electroplating

Disclosed is a method of forming an unsintered, nonwoven, wettable, microporous diaphragm of a fluorocarbon polymer. The diaphragm is prepared by maintaining a nonwoven, fibrous mat of a leachable material in contact with the external surfaces of the fluorocarbon polymer film while hot pressing the halocarbon polymer film above its flow temperature and below its thermal decomposition temperature, and thereafter leaching the fibrous mat out of the halocarbon film. Additionally, monomers having acidic or basic groups may be grafted to the pore walls. Also disclosed is a method of rendering a hydrophobic fluorocarbon polymer film wettable by compressing the film between a pair of nonwoven mats of a leachable fibrous material while maintaining the film above the flow temperature thereof but below its decomposition temperature and then leaching the fibrous material out of the film.

Method of forming a microporous diaphragm

Disclosed is a method of sulfonating polymers having chlorotrifluoroethylene moieties. According to the disclosed method, a liquid composition containing the polymer, an excess of thiourea, and a solvent is maintained above about 100.degree. C. at a pressure sufficient to maintain the composition liquid. A polymer product having trifluoroethylene sulfonic acid and chlorotrifluoroethylene moieties is recovered. Also disclosed is a polymer having (CX.sub.1 X.sub.2 -CX.sub.3 X.sub.4), (CF.sub.2 -CFCl), and (CF.sub.2 -CF(SO.sub.3)) moieties where X.sub.1, X.sub.2, X.sub.3, and X.sub.4 may be hydrogen or fluorine.

Method of sulfonating fluorocarbon polymers and fluorocarbon polymer

Disclosed is a method of preparing an asbestos diaphragm containing a thermoplastic resin. According to the method disclosed herein, an asbestos mat is prepared by drawing the asbestos mat from a salt free, aqueous, asbestos slurry, providing the resin, and thereafter heating the mat to form the resin reinforced mat.

Growing community of inventors

Corpus Christi, TX, United States of America

Thomas A Rechlicz