a process for producing a thermoplastic material including the steps of molecularly orienting a thermoplastic material , grinding the oriented material to a particle size between about 0 . 01 to 10 mm and fusing the ground particulate material to substantially mutually adhere the particles thereby producing a sintered thermoplastic material . the fused product includes discrete fused particles of one or more anisotropically oriented thermoplastic polymers and exhibits isotropic increases in flexural modulus .