The present invention relates to optical fiber communication cables, and more particularly, relates to foamed polyvinylidene fluoride polymer filler rods used in optical fiber cable constructions. The foamed polyvinylidene fluoride polymer filler rod may or may not contain a central strength member. This invention includes cables containing the foamed PVDF filler rods of this invention. The present disclosure provides filler rods that have higher melting temperature than the conventional filler rods and methods of making the filler rods.

Embodiments of an optical fiber cable are provided. The optical fiber cable includes an outer jacket, an inner jacket, a porous insulating layer, and at least one optical fiber. The outer jacket has a first thickness between its inner surface and its outer surface. The inner jacket has a second thickness between its inner surface and its outer surface. The inner jacket is disposed within the outer jacket. The porous insulating layer is disposed between the inner jacket and the outer jacket. The porous insulating layer is configured to reduce the transfer of heat to the inner jacket during combustion of the outer jacket. The optical fiber is disposed within the inner jacket. In the optical fiber cable, the first thickness is less than the second thickness, and each of the outer jacket and the inner jacket include at least one flame retardant additive.

An optical fiber cable that includes subunits is provided. Optical fiber cables are used to transmit data over distance. Generally, large distribution cables that carry a multitude of optical fibers from a hub are sub-divided at network nodes into subunits. To furcate the subunits, the respective jackets of the subunits must balance many different characteristics, including flexibility, temperature tolerance, and safety properties.

An optical fiber cable includes a plurality of optical fibers, a tensile strength member set that is disposed along the plurality of optical fibers in a longitudinal direction of the optical fiber cable, and a sheath that covers the plurality of optical fibers from outside and encloses the tensile strength member set in the sheath. In the optical fiber cable, at least four tensile strength member sets are embedded in the sheath in a state where the four tensile strength member sets are apart from each other in a radial direction of the optical fiber cable, the sheath includes a flame-retardant inorganic substance and a release agent, and a distance from one of the four tensile strength member sets to a surface layer of the sheath is 0.5 mm or more.

A strength member (202, 302) for use in an optical fiber cable and manufacturing method thereof are provided. The strength member comprises a polymer matrix reinforced with one or more yarns, wherein the polymer matrix is a blend of a resin and an inorganic filler. The resin is a polyurethane resin and the inorganic filler is one or more of Magnesium Hydroxide, Aluminium Trihydrate, Zinc borate, Antimony Trioxide, Ammonium Polyphosphate, molybdate based filler and clay nanocomposite. The manufacturing method includes coating the one or more strength yarns with the polymer matrix and curing of the polymer matrix. The inorganic filler is blended in third wet bath of the resin followed by two wet baths of the resin only and the resin is cured after each wet bath. The strength member produces a smoke density of less than 170 at heat flux 50 kW/m.sup.2 for 20 minutes.

An indoor/outdoor micro-duct cable includes a central strength member, and six outer members surrounding the central strength member in a 6@1 configuration. At least one of the outer members is a buffer tube. A plurality of optical fibers are disposed within the buffer tube. The others of the six outer members are filler rods. The cable further includes an outer jacket surrounding the six outer members, the outer jacket having a diameter of less than 9 millimeters and a thickness of less than 1.7 millimeters. The outer jacket is formed from a flame retardant material. The filler rods are formed from a flame retardant material different from the flame retardant material of the outer jacket.

A fiber optic cable includes an optical fiber element including a core and cladding layer. A strength member layer is positioned over the optical fiber element and includes a layer of fiber elements composed of at least 25% high temperature fiber material. An outer jacket layer is positioned over the strength member layer and is formed of a highly flame-resistant material.

Embodiments of an optical fiber cable are provided. The optical fiber cable includes at least one optical fiber, a buffer tube surrounding the at least one optical fiber, and at least one tensile element wound around the buffer tube. The at least one tensile element has a laylength of at least 200 mm. The optical fiber cable also includes an exterior jacket surrounding the tensile element. The exterior jacket is made up of at least one polyolefin, at least one thermoplastic elastomer, and at least one high aspect ratio inorganic filler. Further, the exterior jacket has an averaged coefficient of thermal expansion of no more than 120 (10.sup.−6) m/mK.

An optical fiber cable is provided. The optical fiber cable includes an outer jacket having an outer surface defining an outermost surface of the optical fiber cable and an inner surface defining a central bore. The optical fiber cable includes a plurality of aramid fibers located in the central bore, and the plurality of aramid fibers have a relatively low total linear density such that a total linear density of all aramid fibers within the central bore is less than 10,000 dtex. The optical fiber cable includes at least one optical fiber located within the central bore, and the at least one optical fiber has a proof test of greater than 100 kpsi.

Embodiments of a flame retardant compound are provided. The flame retardant compound includes a polymer base resin and a flame retardant additive distributed within the polymer base resin. The flame retardant additive includes inclusion complexes that are made of at least one guest molecule and at least one carbonific host molecule. The at least one guest molecules is a polyoxometalate ionic liquid. The flame retardant compound achieves a limiting oxygen index of at least 25% according to ISO 4589. Additionally, embodiments of a flame retardant cable are provided that utilize the flame retardant compound as a jacketing material.