Abstract: A retroreflective article comprises a) a microporous substrate (52) containing a plurality of pores (56) which are less than 0.5 ?m in diameter; and b) a layer of reflective material (54) located on the surface (58) of the substrate such that the reflective material layer at least partially obscures a plurality of the pores of the substrate. A method for the production of a reflective article comprises the steps of a) providing a substrate which contains pores which have a diameter of less than 0.5 ?m; and b) applying a layer of reflective material to the substrate in such a way that the reflective material layer at least partially obscures a plurality of the pores of the substrate.

Abstract: Disclosed is a process for preparing copolymers which comprises, in the order stated: (1) adding monomers containing unsaturated carbon-to-carbon bonds, a first polymerization initiator, a second polymerization initiator, and a solvent to a reaction vessel; (2) purging the resulting solution with an inert gas; (3) sealing the reaction vessel and pressurizing it by addition of an inert gas to a pressure of from about 20 to about 600 kilopascals over ambient atmospheric pressure; (4) maintaining the temperature within the pressurized reaction vessel at a temperature of from about 50 to about 100.degree. C. for a period of from about 60 to about 300 minutes; (5) thereafter maintaining the temperature within the pressurized reaction vessel at a temperature of from about 80 to about 115.degree. C.

Abstract: Battery separator comprising a consolidated nonwoven mat of ultrafine polymeric fibers in which at least 10% of said fibers have a diameter less than 1 micron and which mat has an average pore size of less than 3 .mu.m. The fiber mat is formed by meltblowing using modified conditions to produce a self-bonded web having the desired content of ultra fine fibers.