Abstract: A method of forming an enclosure for an electric circuit and the enclosure wherein there is provided a boat of material having a bottom and side wall, placing a material having a substantially higher thermal conductivity and a lower melting point than that of the boat in the boat bottom, heating the material to a temperature above the melting point thereof and below the melting point of the boat to cause the material to flow along the bottom to form a layer of the material thereon and join the layer to the bottom and side wall and removing a sufficient amount of the bottom of said boat to expose the layer. In accordance with a second embodiment, a depression is formed in the bottom, and when the material flows along the bottom, it fills the depression and becomes joined to the bottom. Plural such depressions can be provided. The exterior portion of the bottom is removed to expose the material if the depressions do not extend completely through the bottom.

Abstract: A method of forming an enclosure for an electric circuit and the enclosure wherein there is provided a boat of material having a bottom and side wall, placing a material having a substantially higher thermal conductivity and a lower melting point than that of the boat in the boat bottom, heating the material to a temperature above the melting point thereof and below the melting point of the boat to cause the material to flow along the bottom to form a layer of the material thereon and join the layer to the bottom and side wall and removing a sufficient amount of the bottom of said boat to expose the layer. In accordance with a second embodiment, a depression is formed in the bottom, and when the material flows along the bottom, it fills the depression and become joined to the bottom. Plural such depressions can be provided. The exterior portion of the bottom is removed to expose the material if the depressions do not extend completely through the bottom.

Abstract: Improved continuous process for synthesis of cis-1,4 poly(isoprene). In the commercial process for synthesis of cis-1,4 poly(isoprene) only a portion of the monomer charged is polymerized. The polymer, thus obtained, is separated from the unreacted monomer which in turn is recycled with solvent back into the system for conversion to additional polymer. Fresh monomer must be added from a separate feed to this recycle stream in sufficient quantity to replace or "make-up" for that which was converted to polymer. In the improved process of this invention, this "make-up" isoprene monomer is dried and then is introduced into the process subsequent to the initiation of polymerization of the isoprene monomer already present within the system, but prior to deactivation of the polymerization catalyst. Dehydration of "make-up" isoprene prior to its introduction into the process stream at the above juncture avoids deactivation of the still active catalyst with water.

Abstract: Cyclopentene homopolymers and copolymers are prepared by polymerizing cyclopentene alone or with one or more copolymerizable cycloolefins in the presence of (1) a catalyst comprising (a) at least one compound selected from the group consisting of dialkylaluminum iodides, alkylaluminum diiodides and mixtures of trialkylaluminum compounds with elemental iodine and (b) at least one solvent-soluble tungsten compound, (2) at least one nonconjugated acyclic olefin having at least one hydrogen on each double-bonded carbon atom, and (3) a solvent for the tungsten compound comprising at least one alkyl ester of a saturated carboxylic or dicarboxylic acid. Catalyst component (a) is charged before catalyst component (b). Use of the ester solvent causes a brief induction period allowing excellent process control and resulting in substantially gel-free polymers.