Effect of annealing under high pressure on the structure of oriented polyethylene

The Annealing of Crystals

“…Fischer and Puderbach (1969) found little difference in annealing at atmospheric pressure in a temperature range up to 220°C and a pressure up to 4.2 kb (the sample was drawn to 15 χ at 70°C). Similarly, Zubov et al (1972) saw little increase in crystal dimensions ( L 0 0 2 = 300 A , L l l0 = 130 Α , ρ = 0.968, X-ray long period 350 A , drawn 16 χ at 95°C at 10 mm/min) on annealing for 2 hr at up to 250°C at 7 kb. The latter authors did notice, however, an increasing change of the orthorhombic polyethylene to the monoclinic crystal form II (see Table II.9).…”

“…The annealing of drawn polyethylene crystals at elevated pressure was studied in more detail by Zubov et al (1972) and Bassett and Carder (1973a, b). Similarities to the annealing of drawn crystals at atmospheric pressure (Sect.…”