Zlehit Pri Ban

Hrisanta Nicolaeva Budevska

Rafail V Moshtev

Rafail Velislavov Mostev

Radka D Yankova

Latinca Tantilova Ivanova

Latinka T Ivanova

An improved method for manufacturing membrane battery separators by grafting a vinyl monomer onto a polyolefin film. The method includes irradiation of the film by ultraviolet rays and subsequent grafting of the said film in a five-layer sandwich. The sandwich comprises the irradiated polyolefin film which is covered on each side with a layer of a cellulosic tissue soaked with the monomer or a solution of the monomer, and each cellulosic layer on its turn is covered by an inert polymeric film. The layers of the sandwich are not limited in length and the sandwich is transported at a constant speed over the surface of a heater, maintaining the sandwich at a constant temperature in the range 85.degree. to 95.degree. C. with an accuracy of .+-.1.degree. C. The grafting of the polyolefin film in the sandwich proceeds continuously and isothermally, while it is in contact with the heater surface under a pressure of 10 to 30 g/cm.sup.2 during 10 to 45 minutes.

Method for the production of membrane battery separators

A method of obtaining alkaline battery separators. Such method comprises ultraviolet irradiation in the presence of a sensitizer and oxygen contained in the air of low density polyethylene film at ambient temperature and normal pressure to effect cross-linking and subsequently graft polymerizing an ethylenically unsaturated carboxylic acid monomer into the irradiated film under the action of heat and compression of the film.

Growing community of inventors

Sofia, Bulgaria

Hrisanta Nicolaeva Budevska