Abstract: Integral polymer grids, such as geogrids, are made by stretching and orienting a polypropylene starting sheet material having a defined pattern of holes or depressions in which the polypropylene is at least 50%, and preferably up to about 80%, beta crystals caused by adding a beta nucleating agent to the polypropylene, preferably in concentrations between about 10 ppm to about 100 ppm. Such beta nucleated polypropylene grids exhibit increased yield and break tensile strengths, increased 2% and 5% tensile strengths, increased modulus characteristics, increased torsional stiffness, increased impact strength, and increased grid junction strength. Methods for manufacturing the beta nucleated polypropylene mesh grids are disclosed, along with applications for stabilizing particulate material in civil engineering structures, and the like.

Abstract: Integral polymer grids, such as geogrids, are made by stretching and orienting a polypropylene starting sheet material having a defined pattern of holes or depressions in which the polypropylene is at least 50%, and preferably up to about 80%, beta crystals caused by adding a beta nucleating agent to the polypropylene, preferably in concentrations between about 10 ppm to about 100 ppm. Such beta nucleated polypropylene grids exhibit increased yield and break tensile strengths, increased 2% and 5% tensile strengths, increased modulus characteristics, increased torsional stiffness, increased impact strength, and increased grid junction strength. Methods for manufacturing the beta nucleated polypropylene mesh grids are disclosed, along with applications for stabilizing particulate material in civil engineering structures, and the like.

Abstract: A pleated filter structure includes a pleated filtering substrate and a pleated, polymer, mesh reinforcing sheet or netting for assisting in maintaining the pleated configuration of the filtering substrate. The pleated, polymer, mesh reinforcing sheet or netting includes a mechanically degraded polyalkylene terephthalate as the primary polymer therein. A method of making the pleated filter structure includes the steps of obtaining commercial articles having been made from a high crystallinity, flexible polyalkylene terephthalate; and mechanically degrading said articles to decrease the crystallinity and increase the stiffness of the polyalkylene terephthalate and extruding the mechanically degraded articles into an extruded structure stiffer and more amorphous than the polyalkylene terephthalate in the commercial articles.

Abstract: Integral polymer grids, such as geogrids, are made by stretching and orienting a polypropylene starting sheet material having a defined pattern of holes or depressions in which the polypropylene is at least 50%, and preferably up to about 80%, beta crystals caused by adding a beta nucleating agent to the polypropylene, preferably in concentrations between about 10 ppm to about 100 ppm. Such beta nucleated polypropylene grids exhibit increased yield and break tensile strengths, increased 2% and 5% tensile strengths, increased modulus characteristics, increased torsional stiffness, increased impact strength, and increased grid junction strength. Methods for manufacturing the beta nucleated polypropylene mesh grids are disclosed, along with applications for stabilizing particulate material in civil engineering structures, and the like.

Abstract: Integral polymer grids, such as geogrids, are made by stretching and orienting a polypropylene starting sheet material having a defined pattern of holes or depressions in which the polypropylene is at least 50%, and preferably up to about 80%, beta crystals caused by adding a beta nucleating agent to the polypropylene, preferably in concentrations between about 10 ppm to about 100 ppm. Such beta nucleated polypropylene grids exhibit increased yield and break tensile strengths, increased 2% and 5% tensile strengths, increased modulus characteristics, increased torsional stiffness, increased impact strength, and increased grid junction strength. Methods for manufacturing the beta nucleated polypropylene mesh grids are disclosed, along with applications for stabilizing particulate material in civil engineering structures, and the like.