Nucleation of polyolefins is enhanced by the presence of a polyolefin having an alkali metal sulfonate and chlorine group separately attached thereto and containing an alkali metal hydroxide, preferably sodium hydroxide dispersed in the melt prior to solidification.

A metal processing furnace of the indirect arc type employing opposed electrodes projected into an ionizable atmosphere is provided with novel filter-like, vapor nucleation means which enables the furnace to be utilized for numerous different metal melting/smelting operations in a manner which precludes the presence of metals and metal oxides in their vapor or particle forms in process effluent gases delivered from the furnace. The furance achieves substantial operating advantages in the manufac...

Propylene polymers produced by high-activity support based coordination catalysts are effectively nucleated with benzoic acid and adipic acid, yielding molding resins of high clarity.

Processes and apparatus are disclosed for the separation and collection of contaminants from combustion chamber flue gas by means of heterogeneous nucleation and droplet accretion. The embodiment of the invention is based on: (1) A means of saturating the flue gas proportional to the contaminant volume. (2) A conception of a nucleation chamber where cold gas is added to establish and maintain a continuous supersaturated state throughout its volume. (3) A cold heat exchanger which lowers the part...

In producing thermoplastic polymeric foams, particularly polystyrene, as by melt extrusion with the aid of a blowing agent, nucleation is accomplished by providing in the thermally plastified polymeric material the combination of an ammonium salt of a carboxylic acid, typically ammonium acetate, a carbonate or bicarbonate, and ammonium chloride. Under conditions of extrusion, for example, the two ammonium salts are thermally decomposed to yield both ammonia, as a nucleating agent, and acidic pro...

A polyethylene terephthalate composition comprising the salt of a dimer acid, trimer acid or the salt of a mixture of dimer and trimer acid. The dimer and/or trimer acids are neutralized with a Group IA metal cation, preferably sodium. The composition can contain a filler, plasticizer, impact modifier and/or a polyepoxide.

Isotactic polystyrene is heat fabricated in admixture with minor proportions of melamine, thymine, 2-hydroxybenzimidazole, oxamide and numerous other compounds to provide improved crystallization rates.

The image-recording medium comprises an actinic ray sensitive material and a metallic compound which acts as a nucleation-inducing medium dispersed in a film-forming vehicle and preferably coated on a substrate. The actinic ray sensitive material is preferably zinc oxide, while the nucleation-inducing medium is preferably a copper-containing compound. The process is directed to forming and using the medium and comprises dispersing the sensitive material in the vehicle with the aid of a vehicle s...

Urethane compositions generally free of phase separation patterns and flow lines are produced. One method includes the utilization of a nucleating compound which is generally added to a urethane prepolymer before any chain extension thereof. Examples of nucleating agents include urethanes, ureas and allophanates such as carboxylic acids, organic acid and anhydrides, amides, imides and the like. Another method includes adding a very small initial incremental amount of a curing agent to the prepol...

This disclosure relates to methods for nucleating castings to control their grain formation and teaches the addition of a slug of solid material to the superheated melt shortly before pouring for the purpose of forming and maintaining crystalline dendrite fragments in the melt during and after it has been poured into the mold.