Flash-spinning process and solution

A process for flash-spinning a web of plexifilamentary film-fibril strands of synthetic fiber-forming polyolefin and laying down the web to form a nonwoven sheet material therefrom, the process comprising the steps of:

• generating a spin fluid consisting essentially of 5 to 35 weight percent, based on the total weight of the spin fluid, of synthetic fiber-forming polyolefin and a spin agent, the spin agent comprised of at least 90% by weight, based on the total weight of the spin agent, of hydrocarbons comprised substantially exclusively of carbon and hydrogen atoms, said hydrocarbons comprised of at least 25% by weight of unsaturated hydrocarbons selected from the group consisting of alkenes having the formula CnH2n and cycloalkenes having the formula CnH2n−2, where n equals 4, 5, 6, 7, or 8;
• flash-spinning the spin fluid at a pressure that is greater than the autogenous pressure of the spin fluid into a spin cell maintained at lower pressure to form a web of plexifilamentary film-fibril strands of said synthetic fiber-forming polyolefin;
• applying an electrostatic charge to the web by passing the web through an electric corona;
• laying the web onto a grounded surface to form the web into a fibrous batt;
• consolidating said fibrous batt to form a fibrous nonwoven sheet;
• and
• removing said fibrous nonwoven sheet from the spin cell.