Compositions are provided which comprise 50-80% of a synthetic wax, such as a Fischer-Tropsch wax, in combination with 10-50% of a polyethylene material having a Brookfield viscosity at 284.degree. F. greater than about 5000 centipoise. The compositions serve as replacements for commercially available low viscosity polyethylenes, i.e., polyethylenes having Brookfield viscosities at 284.degree. F. of less than about 1000 centipoise, in such applications as lubricating plastic extrusions and coating paperboard stock. The compositions can be prepared by melting and then mixing the components. Accordingly, custom tailoring of the compositions for specific applications can be readily performed.

Erasable coatings for xerography paper comprise a pigment such as calcium carbonate in a binder such as an aqueous emulsion of an acrylic polymer. The erasability of the coating is improved by replacing at least 15 wt % of the binder with a polyalkane or (preferably) polyalkene wax, such as an aqueous emulsion of a polyolefin.

The present invention provides a high performance polymer-base material capable of dissipating transient thermal energy generated by an electronic module, such as a heat-generating power device. The methods of the present invention involve adding a suitable thinner to reduce the viscosity and increase the volume of a polymer-base matrix material so that a large amount of thermal absorbing particles may be added. The final cured product may have a filler content of more than 80 weight %. Further, the present invention provides a new and reduced cost formulation of a polymer-base thermal transient suppression material containing organic wax particles.

A polymer produced by a transition metal containing catalyst useful for the polymerization of .alpha.-olefins is prepared by (A) forming in an inert atmosphere which excludes oxygen and moisture a slurry of (1) a porous inorganic oxide support material selected from the group consisting of silica, alumina, or a combination of silica and alumina, said support material containing not greater than about 5 millimoles of hydroxyl groups per gram of support material and a particle size not greater than about 10 microns and a surface area of from about 50 to about 800 m.sup.2 /g in an inert organic liquid medium; (B) mixing said slurry with (2) an alkoxide and stirring the resultant mixture at a temperature of from about -20.degree. C. to about 120.degree. C. for a time sufficient to saturate the surface of the support material; (C) mixing the product form (B) with (3) a titanium compound or a combination of a titanium compound and (4) a vanadium compound and stirring the resultant mixture at a temperature of from about -20.degree. C. to about 120.degree. C. for a time sufficient to allow complete reaction of the titanium compound and the vanadium compound with the organomagnesium moieties remaining on the solid support; (D) mixing the product from (C) with an inert organic solution of (5) a Group IIIA metal alkyl halide at a temperature of from about -20.degree. C. to about 120.degree. C. for a time sufficient to complete the reduction of the titanium and vanadium, if present, compounds to their final oxidation state. Ethylene/alpha-olefin copolymers which have greater than 17 percent high density fraction and a M.sub.w /M.sub.n ratio of less than about 3.6 are shown to be useful in making cast films which have good stretchability and good puncture resistance. Copolymers of the present invention having the specified properties are especially useful in making the films.