Rigid fiber network structures having improved post-yield dimensional recovery, method of making same, and articles incorporating same

A method of making a rigid three-dimensionally shaped fiber network structure having improved post-yield dimensional recovery, comprising the steps of:

• (1) providing at least one oriented, semi-crystalline monofilament yarn comprising a thermoplastic polymer;
• (2) subjecting the monofilament yarn to a fabric-forming process so as to produce a deformable fabric, the deformable fabric containing a plurality of monofilament cross-over points formed by the monofilament yarn;
• (3) subjecting the deformable fabric to an area-enlarging deformation process in a shaping mold at an elevated temperature so as to form an initial, resilient, self-supporting network structure containing a deformed fabric having a three-dimensional shape, the deformed fabric having a base region and a plurality of deformations disposed as a two-dimensional array on the base region, the elevated temperature being higher than the glass transition temperature of the thermoplastic polymer so as to permanently deform the thermoplastic polymer but sufficiently below the melting temperature of the thermoplastic polymer so as to avoid softening and loss of molecular orientation of the thermoplastic polymer, the initial network structure having sufficient stiffness so as to be capable of maintaining the three-dimensional shape thereof;
• (4) demolding the initial network structure;
• (5) adding a crosslinkable resin to the demolded network structure to form a resin-impregnated network structure;
• (6) curing the resin in the resin-impregnated network structure so as to effect bonding of all or substantially all of the monofilament cross-over points, thereby converting the demolded initial structure into a rigid three-dimensionally shaped network structure having improved post-yield dimensional recovery.

A method of making a rigid three-dimensionally shaped fiber network structure having improved post-yield dimensional recovery, comprising the steps of:

• (1') providing at least one oriented, semi-crystalline monofilament yarn comprising a thermoplastic polymer;
• (2') subjecting the monofilament yarn to a fabric-forming process so as to produce a deformable fabric, the deformable fabric containing a plurality of monofilament cross-over points formed by the monofilament yarn;
• (3') applying a crosslinkable resin to the deformable fabric to form a resin-impregnated deformable fabric;
• (4') subjecting the resin-impregnated deformable fabric to an area-enlarging deformation process in a shaping mold at an elevated temperature so as to form an initial, resilient, self-supporting, resin-impregnated network structure containing a deformed fabric having a three-dimensional shape, the deformed fabric having a base region and a plurality of deformations disposed as a two-dimensional array on the base region, the elevated temperature being higher than the glass transition temperature of the thermoplastic polymer so as to permanently deform the thermoplastic polymer but sufficiently below the melting temperature of the thermoplastic polymer so as to avoid softening and loss of molecular orientation of the thermoplastic polymer, the initial network structure having sufficient stiffness so as to be capable of maintaining the three-dimensional shape thereof;
• (5') demolding the initial resin-impregnated network structure;
• and
• (6') curing the resin in the resin-impregnated network structure so as to effect bonding of all or substantially all of the monofilament cross-over points, thereby converting the demolded initial structure into a rigid three-dimensionally shaped network structure having improved post-yield dimensional recovery.

A method of making a rigid three-dimensionally shaped fiber network structure having improved post-yield dimensional recovery, comprising the steps of:

• (1") providing at least one oriented, semi-crystalline monofilament yarn comprising a thermoplastic polymer;
• (2") subjecting the monofilament yarn to a fabric-forming process so as to produce a deformable fabric, the deformable fabric containing a plurality of monofilament cross-over points formed by the monofilament yarn;
• (3") subjecting the deformable fabric to an area-enlarging deformation process in a shaping mold at an elevated temperature so as to form an initial, resilient, self-supporting network structure containing a deformed fabric having a three-dimensional shape, the deformed fabric having a base region and a plurality of deformations disposed as a two-dimensional array on the base region, the elevated temperature being higher than the glass transition temperature of the thermoplastic polymer so as to permanently deform the thermoplastic polymer but sufficiently below the melting temperature of the thermoplastic polymer so as to avoid softening and loss of molecular orientation of the thermoplastic polymer, the initial network structure having sufficient stiffness so as to be capable of maintaining the three-dimensional shape thereof;
• (4") applying a crosslinkable resin to the initial network structure to form a resin-impregnated initial network structure;
• (5") demolding the initial resin-impregnated network structure;
• and
• (6") curing the resin in the resin-impregnated network structure so as to effect bonding of all or substantially all of the monofilament cross-over points, thereby converting the demolded initial structure into a rigid three-dimensionally shaped network structure having improved post-yield dimensional recovery.