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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 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 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.
Compared to other fluoropolymers, it has an easier melt process because of its relatively low melting point of around 177 °C. Processed materials are typically in the non-piezoelectric alpha phase. The material must either be stretched or annealed to obtain the piezoelectric beta phase.
Melting point 195–265 °C (383–509 °F; 468–538 K) [ 1 ] Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
At room temperature, it spontaneously converts into the form-I with the melting point of 135 °C and density of 0.95 g/cm 3. [ 1 ] PB-1 generally resists chemicals such as detergents, oils, fats, acids, bases, alcohol, ketones, aliphatic hydrocarbons and hot polar solutions (including water). [ 3 ]
When it is converted to the covalent red phosphorus, the density goes to 2.2–2.4 g/cm 3 and melting point to 590 °C, and when white phosphorus is transformed into the (also covalent) black phosphorus, the density becomes 2.69–3.8 g/cm 3 and melting temperature ~200 °C. Both red and black phosphorus forms are significantly harder than ...
ASA can be used as an additive to other polymers, when their heat distortion (resulting in deformed parts made of the material) has to be lowered. [6] ASA can be coextruded with other polymers, so only the ASA layer is exposed to high temperature or weathering. ASA foils are used in in-mold decoration for forming e.g. car exterior panels. [6]