Abstract: A method and apparatus for controlling the density of a foam. The method involves measuring the electrical conductivity of a foam wherein the electrical conductivity of the foam varies with the density thereof and adjusting the density of the foam in response to the measured electrical conductivity to prepare a foam having a desired density. The apparatus comprises means for generating and applying a foam, said means being connected by an enclosed pathway. Located within the enclosed pathway is an electrical conductivity sensor. The conductivity sensor is electronically connected to a translation means. The conductivity sensor provides an electrical signal, related to conductivity of the foam, to the translation means. The translation means is connected to a gas flow controlling means.

Abstract: A steam expandable alkenyl aromatic polymer composition and methods of preparation are provided. The composition is mixed with a volatile blowing agent containing, as a primary blowing agent, dichlorodifluoromethane and as a secondary blowing agent, a halogenated hydrocarbon, a hydrocarbon, or an aliphatic alcohol containing from 1 to 4 carbon atoms, the secondary blowing agent having a normal atmospherpic boiling point of from about 0.degree. to about 100.degree. C. The composition may be expanded by steam immediately after extrusion foaming or may be expanded after aging of the composition which has been impregnated with volatile blowing agent.

Abstract: A polymer foam made from a blend of a low density ethylenic polymer and styrenic polymer utilizing a volatile blowing agent and a free radical generating compound as a crosslinking agent. The free radical generating compound provides light crosslinking and increases the foamability of the polymer blend.

Abstract: A device for testing a sample of foam material and a method for making such a test include compressing the sample repetitively by means of a dropped weight. The weight includes a plunger which moves vertically in a sliding bearing arrangement. The plunger is raised by a solenoid and allowed to drop so as to compress the sample only by a predetermined percentage of its original diameter. The force applied to the sample is monitored during this compression operation and the ratios of forces between the initial force measurement and the force measurement made during subsequent drops provides a quantitative indication of the weakness in the foam cell structure.

Abstract: A waste disposal mixer is shown suitable for the encapsulation of radioactive wastes in synthetic resins. The mixer permits the selective discarding of the agitator member and of a drip pan selectively positionable to receive dripping material from the agitator. The agitator can be selectively replaced, all movements being controlled remotely.

Abstract: Plastic containers are treated to provide increased barrier properties to organics and gases such as oxygen by treating the interior surface of the container with SO.sub.3 gas. The SO.sub.3 gas is provided by inserting a solid pellet of poly-SO.sub.3 into the container and evaporating the SO.sub.3 such as with microwave energy. A solid neutralizing agent such as ammonium carbonate is then placed into the container and evaporated with microwave energy to form ammonia which neutralizes the sulfonic acid groups on the surface interior of the container.

Abstract: A polymer foam made from a blend of a low density ethylenic polymer and styrenic polymer utilizing a volatile blowing agent and a free radical generating compound as a crosslinking agent. The free radical generating compound provides light crosslinking and increases the foamability of the polymer blend.

Abstract: Block copolymers of the AB(BA).sub.n configuration are employed in the preparation of asphalt blend concentrates. Advantageously asphalt is blended with polymer solution from polymerization reactor and subsequently devolatilized.

Abstract: A method is disclosed for encapsulating and solidifying spent ion exchange beads contained in a container to form an ion exchange bed with a solidification resin without the necessity for applying shear in the bed by an external force such as by a mixing impeller. A solidification resin is flowed through the ion exchange bed by plug flow to intermix with and encapsulate each ion exchange bead therein. The resin is cured to form a uniform, solidified monolith of said ion exchange beads in said container. When the ion exchange bed contains free water, the process also effects the removal of substantial portions of the free water and also emulsifies and solidifies free water remaining in the bed.

Abstract: A process for producing polymers or copolymers of ethylene, in which ethylene, optionally together with one or more copolymerizable compounds, is polymerized at a pressure above 50,000 kPa and a temperature of between 100.degree. and 400.degree. C. in the presence of an initiator, using an autoclave reactor and a tubular reactor connected in series with said autoclave reactor. The monomeric mixture in the presence of the initiator is passed first into a stirred autoclave, in which it is partially polymerized. Thereafter the reaction mixture from said autoclave, is passed through a heat exchanger, cooled to a pre-determined value, and then subsequently passed to a non-cooled tubular reactor, in which the further polymerization is carried out under adiabatic conditions.

Abstract: An improvement in the process of encapsulating aqueous liquid waste materials in liquid thermosettable resins of the group consisting of vinyl ester resins, unsaturated polyester resins, and mixtures thereof, wherein the waste is emulsified in the resin, which comprises increasing the amount of waste material emulsified in a given amount of resin by incorporating in the resin-waste emulsion both a water soluble salt of carboxymethyl cellulose and a water-soluble polymeric substance containing a carbon chain having a plurality of --COOH groups or derivatives thereof.

Abstract: An improvement in the process of encapsulating aqueous liquid waste materials in liquid thermosettable resins of the group consisting of vinyl ester resins, unsaturated polyester resins, and mixtures thereof by forming an emulsion of such waste materials in said resins, which comprises increasing the amount of waste material incorporated in a given amount of resin by incorporating in the waste-resin emulsion a water-soluble salt of carboxymethyl cellulose.

Abstract: An improvement in the process of encapsulating waste materials in aqueous liquid or finely divided, dry solid form, in liquid thermosettable resins of the group consisting of vinyl ester resins, unsaturated polyester resins, and mixtures thereof, which comprises increasing the amount of waste material incorporated in a given amount of resin by adding thereto a water-soluble polymeric substance containing a carbon chain having a plurality of --COOH groups or derivatives thereof.

Abstract: A method is provided for filling a subterranean void, e.g. a mined out cavity such as a tunnel. An aqueous suspension of solid particles the mass of which when at rest has a permeability of about 40 darcies, preferably less than 20 darcies, is injected into the void to effect complete filling.