Shaped articles having improved properties

A method for preparing a nonwoven web having significantly improved tensile strength characteristics which comprises

• (A) melting a thermoplastic composition which includes a thermoplastic polyolefin and an improved additive system having a first component and a second component;
• (B) forming fibers by extruding the resulting melt through a die;
• (C) drawing the fibers;
• and
• (D) collecting the fibers on a moving foraminous surface as a web of entangled fibers;
• in which:
• (1) the first component is an alkyl-substituted polysiloxane having the general formula, ##STR7## in which:
• (a) R.sub.1 -R.sub.9 are independently selected monovalent C.sub.1 -C.sub.3 alkyl groups;
• (b) R.sub.10 is a monovalent C.sub.6 -C.sub.30 alkyl group;
• (c) m represents an integer of from about 5 to about 50;
• (d) n represents an integer of from 0 to about 200;
• (e) the first component has a number-average molecular weight of from about 3,000 to about 36,000;
• and
• (f) the first component has a polydispersity of from about 1.1 to about 2.5;
• (2) the second component is a hydrophobic fumed silica, in which the weight ratio of the first component to the second component is in the range of from about 10 to about 70;
• and
• (3) the improved additive system is present in an amount of from about 0.01 to about 3 percent by weight, based on the amount of thermoplastic polyolefin.

A composition which comprises a first component and a second component, in which:

• (A) said first component is an alkyl-substituted polysiloxane having the general formula, ##STR8## in which:
• (1) R.sub.1 -R.sub.9 are independently selected monovalent C.sub.1 -C.sub.3 alkyl groups;
• (2) R.sub.10 is a monovalent C.sub.6 -C.sub.30 alkyl group;
• (3) m represents an integer of from about 5 to about 50;
• (4) n represents an integer of from 0 to about 200;
• (5) said first component has a number-average molecular weight of from about 3,000 to about 36,000;
• and
• (6) said first component has a polydispersity of from about 1.1 to about 2.5;
• and
• (B) said second component is a hydrophobic fumed silica, in which the weight ratio of the said first component to said second component is in the range of from about 10 to about 70.