Polystyrene

Structural formula
Strukturformel Polystyrol
general
name polystyrene
other names polystyrene, Styrodur, PS-E
sum formula (C 8 H 8) n
CAS number 9003-53-6
short description amorphous, transparent thermoplastic · Polymere
characteristics
mol mass 104.15 g mol
state of aggregation firmly
density 1050 kg/m ³
electrical conductivity (σ) 10,-16 S/m
heat conductivity 0.08 W·m -1·K of -1
safety references
of Gefahrensymbole

no

R and S-sentences none
as far as possible and common, are used SI-UNITs. If not differently notes, the indicated data apply with standard conditions.

Polystyrene (abbreviation HP, occasionally also Polystyren mentioned) is an amorphous, transparent thermoplastic.It is a far common plastic, which is used in many ranges of the daily life.

Polystyrene is used either as thermoplastic processable material or as foam material. Well-known trade names for polystyrene are Luran, Lustron, polystyrene, Styrodur, Styroflex and Sagex (the latter in Switzerland).

Table of contents

characteristics

polystyrene are not steady to caustic solutions and mineral acids, to gasoline, Keton and aldehydes , in addition is it UV - sensitive. The density of solid polystyrene lies between 1,04 and 1,09 g/cm ³, up-foamed polystyrene has a density between 0,02 and 0,06 g/cm ³.

Polystyrene is highly transparent. Hard, inflexibly and form-stably. Polystyrene is well steady to aqueous solutions. HP is however small steady opposite solvents.

SolidPolystyrene is hard and impactsensitive. It produces brittle sound with the Beklopfen (Butterdosen), is highly transparently, in all colors dyable and not age-resisting (cracking). It is a little heat resistant and only conditionally to 70 °C applicable. Due to accelerated aging polystyrene should not be heated up however over 55 °C.The crystallite melt begins with 90 °C.

Polystyrene burns flame and a blumigen, süsslichen smell with bright, yellow, strong Russian that after benzene. Steams should not be inhaled, them are possibly injurious to health, because they can contain styrene beside other decomposition products also (see also: Physiological effect).

Foamed polystyrene has a smaller mechanical firmness and elasticity compared with solid polystyrene. It is white and obscure and has a very small heat conductivity. In order to decompose large quantities foam polystyrene, one needs only little acetone. The acetone sets with the up-foamed materialthe enclosed propulsion gas again freely.

Solid polystyrene is inclined very strongly to the shatter crack formation.

physiological effect

thermoplastic polystyrene is physiologically without heistation and also certified for food packing without reservation.

stability against chemicals

the chemical stability of polystyrene is temperature-dependent. One is followingrough characterisation of the stability against some important classes indicated by chemicals at ambient temperature:

Material class stability
of aldehydes *
aliphatic alcohols ***
esters *
Ether *
Ketone *
hydrocarbons aliphatic *
hydrocarbons aromatically *
caustic solutions ***
oxidizing agents *
weak acids **
strong acids **

“*” = badto no stability against the material class (already unique, brief exposition can damage the material)

“**” = good/reduced stability against the material class (material is steady for a reduced time and becomes possibly. only reversibly damaged)

“***” = good stability against those the material class (also are enoughExposition does not add the material damage to

types - production and processing

structural formula of the styrene monomer

polystyrene are won by polymerization of the monomer styrene, which exhibits unusual polymerization characteristics.

Polystyrene can become complete recycled.

foam materials

foam polystyrene is particularly under the trade name PolystyreneBASF) admits become. For years the IVH (trade association expanded polystyrene e takes the 1990er. V.) the rights at the name polystyrene truely. Only the manufacturers of PS-E (E of xpandierter P oly s tyrol expanded polystyrene) may call thereafter their material polystyrene. These manufacturers submitthe special quality requirements of the IVH.

Depending upon kind of manufacture z becomes between the rather roughporous PS-E. B. Polystyrene (® BASF), and the fine-more porous XPS (E x of trudierter P oly s tyrol expanded polystyrene), z. B. Styrodur (® BASF) differentiated. XPS becomes due to its high pressure strength and small Water absorption for example with the insulation of buildings against soil assigned.

Of PS-E the structure from approximately 2-3 mm of large, bonded together foam balls, the z is characteristic. B. step a polystyrene plate clearly when breaking to day.

foils and plates

for packing purposes become also transparentFoils made of polystyrene. Foils and plates are manufactured by extruding.

use

in electro-technology is used polystyrene because of the good isolation characteristic. Except the isolation of cable it is used for the production of switches , spools and housings for electrical appliances. Polystyrene becomesfor mass-produced articles, in the building industry as insulating material, when model and building of window blinds, fine mechanics, use sediment bowls and for the solid rescue west. As food packing foam polystyrene is without reservation certified, for example in yogurt cups, blowing he packing etc.

Foamed polystyrene is used as shock-absorbing packing material or for thermal insulation for buildings.

There foam polystyrene very muchwell with a thermal saw to be cut can, and, it is at the same time very inexpensive as building material in (architecture) the model construction was established.

Polystyrene is also one of the raw materials of napalm - B, which in incendiary bombs use finds.

Strained polystyrene foil (trade name: Styroflex, Trolitul) becomes together with aluminum or tin foilfor the production of condensers for high-frequency engineering uses.

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