Search results
Results from the WOW.Com Content Network
The Gmelin rare earths handbook lists 1522 °C and 1550 °C as two melting points given in the literature, the most recent reference [Handbook on the chemistry and physics of rare earths, vol.12 (1989)] is given with 1529 °C.
The melting point of α-crystalline regions is given as 185 [15] [16] to 220 °C, [15] [17] the density as 0.936 to 0.946 g·cm −3. [ 18 ] [ 19 ] The β-modification is in comparison somewhat less ordered, as a result of which it forms faster [ 20 ] [ 21 ] and has a lower melting point of 170 to 200 °C.
Polar and bowlic LCPs are ferroelectrics, with reaction time order-of-magnitudes smaller than that in conventional LCs and could be used to make ultrafast switches. Bowlic columnar polymers possess long, hollow tubes; with metal or transition metal atoms added into the tube, they could potentially form ultrahigh-Tc superconductors. [17]
The polymerization can take place in a non-polar solvent (in which case the polymer forms as a slurry) or in neat trioxane (e.g. in an extruder). After polymerization, the acidic catalyst must be deactivated and the polymer stabilized by melt or solution hydrolysis to remove unstable end groups.
The β, γ, and δ phases feature a parallel arrangement of dipoles, rendering them polar crystals with a non-zero dipole moment. Among these phases, the β phase stands out due to its remarkable remnant polarization and the highest dipolar moment per unit cell, garnering more interest compared to the others. [ 6 ]
Polyether ether ketone (PEEK) is a colourless organic thermoplastic polymer in the polyaryletherketone (PAEK) family, used in engineering applications. It was invented in November 1978 [2] and brought to market in the early 1980s by part of Imperial Chemical Industries (ICI), the PEEK division was acquired through a management buyout, giving rise to Victrex PLC.
{{Periodic table (melting point)|state=expanded}} or {{Periodic table (melting point)|state=collapsed}}This template's initial visibility currently defaults to autocollapse, meaning that if there is another collapsible item on the page (a navbox, sidebar, or table with the collapsible attribute), it is hidden apart from its title bar; if not, it is fully visible.
As quoted from various sources in: J.A. Dean (ed), Lange's Handbook of Chemistry (15th Edition), McGraw-Hill, 1999; Section 6, Thermodynamic Properties; Table 6.4, Heats of Fusion, Vaporization, and Sublimation and Specific Heat at Various Temperatures of the Elements and Inorganic Compounds