Abstract: An improved method is described for solvent casting ultrathin non-porous methylpentene polymer films. The casting solution comprises methylpentene polymer or a mixture thereof with organopolysiloxane-polycarbonate copolymer dissolved in a solvent system and is characterized by being able to spontaneously spread over the surface of the liquid casting substrate. In a preferred embodiment, large-area films less than 200 Angstroms in thickness may be repeatedly formed. The solidified films remain relatively free of tensile stress during formation. The casting solution is deposited in a narrow, longitudinally-extending defined region at the surface of the casting substrate. The surface area and perimeter of the defined region are enlarged over the surface of the casting substrate in a manner whereby the casting solution is moved relative to the casting substrate and, after desolvation, the polymer film formed remains stationary relative to the casting substrate and relatively free of tensile stress.

Abstract: An irreversible heat-activatable switch includes a heat-shrinkable plastic sleeve and a pair of elongate resilient electrical conductors mounted in cantilevered manner within the sleeve interior. The conductors have a pair of diverging-converging (e.g. arcuate) portions including regions proximate the sleeve. Each arcuate portion extends from the mounted end portion of its conductor and terminates in another end portion provided with an electrical contact. The end portions are so opposed that the open-closed electrical circuit character of the pair of contacts irreversibly changes responsive to movement of the arcuate portions resulting from heat-shrinking the sleeve.

Abstract: An improved method is described for solvent casting ultrathin non-porous methylpentene polymer films. The casting solution comprises methylpentene polymer of a mixture thereof with organopolysiloxane-polycarbonate copolymer dissolved in a solvent system and is characterized by being able to spontaneously spread over the surface of the liquid casting substrate. In a preferred embodiment, large-area films less than 200 Angstroms in thickness may be repeatedly formed. The solidified films remain relatively free of tensile stress during formation. The casting solution is deposited in a narrow, longitudinally-extending defined region at the surface of the casting substrate. The surface area and perimeter of the defined region are enlarged over the surface of the casting substrate in a manner whereby the casting solution is moved relative to the casting substrate and, after desolvation, the polymer film formed remains stationary relative to the casting substrate and relatively free of tensile stress.