Abstract: A polymer reinforcing material, consisting of a particulate or filamentary mineral component having a thin polymer-interactive layer, averaging about 5-500 Angstrom in thickness, of silicon-free and heavy metal-free organic molecules chemically bonded to its surface by covalent bonding, when used in relatively small amounts in the range from 1 to 20 phr is capable of providing superior retention or increase of desirable polymer properties especially impact resistance, compared to the use of conventional reinforcement in the same polymer, while providing increased stiffness and retention of strength at elevated temperatures.

Abstract: A fiber preparation containing or consisting of a polyglycol ether mixed formal of the formulaR.sub.1 --(OC.sub.2 H.sub.4).sub.n --OCH.sub.2 OCH.sub.2 CH.sub.2 OR.sub.2in which R.sub.1 is a linear or branched alkyl or alkenyl radical of from 8 to 22 carbon atoms, R.sub.2 is a linear alkyl radical of from 1 to 4 carbon atoms and n is an integer of from 3 to 30.