Abstract:
Visible light actually emitted by a light emitting diode (LED) at a point source is perceived by a viewer of that LED to be sufficiently diffuse to hide the point source. A panel between the LED and the viewer is made from a mixture of polyvinyl halide polymer in a continuous phase and visible light refracting polymeric particles in a discontinuous phase. The polyvinyl halide has a refractive index different from the particles, and both have a different refractive index from air. Optical refraction causes the diffusion, providing “hiding power” to the panel, which is beneficially, inherently flame retardant because of the use of the polyvinyl halide as the continuous phase.
Abstract:
A polyvinyl halide compound has thermal conductivity and includes polyvinyl halide resin, natural or synthetic graphite of flake or spheroid form, and at least 0.5 weight percent of epoxidized vegetable oil. Selection of types and amounts of graphite and epoxidized vegetable oil provide thermal conductivity while other desirable properties of the compound are suitably maintained. The compound can be used for making any end use article that needs flame retardance and good thermal management and is especially useful as a thermally conductive material to replace die cast or extruded aluminum heat sinks in industrial applications, such as LED lighting fixtures.
Abstract:
A polyvinyl halide compound, alone or alloyed with thermoplastic polyurethane, is used as a flexible layer for over-molding a rigid polymer substrate. Selection of types and amounts of calcium carbonate for the overmolding layer improves peel strength to achieve cohesive failure of the flexible overmolding layer rather than adhesive failure of the interface between the flexible overmolding layer and the rigid polymer substrate.
Abstract:
Use of polycaprolactone plasticizer is disclosed for flexible polyvinyl chloride compounds. The compounds can pass the very demanding UL-910 plenum burn test for usage in wire and cable articles.