What is isotactic polystyrene?
Isotactic Polystyrene: They consist of long hydrocarbon chains, with a phenyl group connected to every other carbon atom. The Syndiatactic form is highly regular and crystalline. Atactic polystyrene is irregular and amorphous (disordered) and the Isotactic form is semi-crystaline.
Which polymerisation process is used for preparation of isotactic polystyrene?
The preparation of the isotactic polystyrene block involved a novel anionic polymerization technique using low temperatures and the addition of BuOLi for stereospecific placement.
Can isotactic polystyrene crystallize?
When isotactic polystyrene (i-PS) is crystallized from the melt or from the glassy state at rather large supercooling an additional melting peak appears on the curve during scanning in a differential calorimeter.
Does polystyrene crystallize?
We observe and characterize the crystallization of atactic polystyrenes (PS) of nearly oligomeric Mw using atomic force microscopy. We find that the low Mw polystyrene exhibits observable crystals on the surface. The crystals appear to be a few nm thick and nm to microns wide.
At what temperature does polystyrene melt?
6.6. 2 Polystyrene Properties
| Property | Units | Syndiotactic PS |
|---|---|---|
| Refractive index | 1.59 | |
| Melting point | °C | 270 |
| Glass transition temperature | °C | 100 |
| HDT at (0.46 MPa or 66 psi) | °C | 108 |
What temperature does polystyrene melt?
Is polystyrene amorphous or crystalline?
amorphous polymer
Polystyrene, also known commercially as crystal polystyrene or general-purpose polystyrene, is an amorphous polymer and has the particular properties of high clarity, being colorless, hard, but rather brittle.
What happens to polystyrene when heated?
As a thermoplastic polymer, polystyrene is in a solid (glassy) state at room temperature but flows if heated above about 100 °C, its glass transition temperature. It becomes rigid again when cooled.
At what temperature does polystyrene ignite?
In the absence of an energy source (pilot flame) the self-ignition temperature of melted EPS in its standard grade is 450° C. After ignition of standard grade EPS, burning will readily spread over the exposed surface of the EPS, and it will continue to burn until all EPS is consumed.
What temp does polystyrene melt?
410-480 °F
What are the properties of PS?
| Property | Value |
|---|---|
| Technical Name | Polystyrene (PS) |
| Chemical Formula | (C8H8)N |
| Melt Temperature | 210-249 °C (410-480 °F) *** |
| Typical Injection Molding Temperature | 38 – 66 °C (100 – 150 °F) *** |