Geogrid composed of polyethylene terephthalate and polyolefin bicomponent fibers and a process for the preparation thereof

摘要

This invention claims a warp knit, weft inserted geogrid fabric without a topcoat, comprising a bicomponent fiber having filaments each with a sheath of a polyolefin material and about 0.5 to about 2 weight percent carbon black and a core of polyethylene terephthalate. This invention also claims the process for the making thereof comprising the steps of: (a) providing polyethylene terephthalate with an intrinsic viscosity of at least 0.89 deciliters per gram as determined from a solvent base of orthochlorophenol at 25 DEG C; (b) providing an adhesive polyolefin; (c) passing said polyethylene terephthalate in a molten state into an apparatus for spinning bicomponent sheath-core filaments to form the core of each said filament of a bicomponent fiber; (d) passing said adhesive polyolefin in a molten state containing about 0.5 weight percent to about 2 weight percent carbon black into said apparatus to form a sheath about said core of each said filament of said bicomponent fiber; (e) spinning and drawing said bicomponent fiber comprised of filaments each with said sheath of said adhesive polyolefin material and about 0.5 weight percent to about 2 weight percent carbon black and said core of said polyethylene terephthalate; (f) applying a finish at a level of about 0.4 weight percent to about 0.8 weight percent to said bicomponent fiber; (g) sizing and warping said bicomponent fiber; (h) weaving or knitting said bicomponent fiber into a fabric; and (i) bonding said fabric by fusing said sheath using a heating medium.