Polystyrene is created via the polymerization of styrene – a petroleum based, liquid hydrocarbon monomer. In this three-step synthesis, styrene is formed via the radical bromination of ethylbenzene and the elimination reaction of (1-bromo-ethyl)benzene.

Which catalyst is suitable for the preparation of polystyrene from styrene?

The acid catalyst now used is a zeolite, ZSM-5, an aluminosilicate.

What is the molecular mass of polystyrene?

About a few thousand monomers typically comprise a chain of polystyrene, giving a molecular weight of 100,000–400,000 g/mol.

Is polystyrene a homopolymer or copolymer?

Polystyrene is typically (but not always) a homopolymer meaning that it is composed only of the monomer styrene in combination with itself. Depending on the type of PS it could be classified as a “thermoplastic” or a “thermoset” material.

Why is polystyrene a solid?

Polystyrene is one of the most widely used kinds of plastic. It is a polymer made from the monomer styrene, a liquid hydrocarbon that is commercially manufactured from petroleum by the chemical industry. Polystyrene is a thermoplastic substance, it melts if heated and becomes solid again when cool.

What is polystyrene chemistry?

Polystyrene is a plastic. As its name suggests, it is made up of many (“poly”) styrenes. Styrene is a small organic compound with the chemical formula C6H5CH=CH2. Styrene is named for storax balsam, which is an oily resin produced by sweetgum trees (Liquidambar styraciflua). Styrene is a clear, colourless liquid.

Is polystyrene amorphous or crystalline?

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.

Is polystyrene an addition polymer?

Addition polymers are formed by a reaction in which monomer units simply add to one another. The monomers usually contain carbon–carbon double bonds. Addition polymers include polystyrene, polyethylene, polyacrylates, and methacrylates.

Can polystyrene be branched?

Branched polystyrenes of high molecular weight and high branching degree were obtained. In addition, low temperature of polymerization reaction also contributed to the high average molecular weight and the high average branching degree of branched polystyrene.

Is polystyrene thermoplastic or thermosetting?

Polystyrene (PS) plastic is a naturally transparent thermoplastic that is available as both a typical solid plastic as well in the form of a rigid foam material. PS plastic is commonly used in a variety of consumer product applications and is also particularly useful for commercial packaging.

What is the melting point of syndiotactic polystyrene?

This form is highly crystalline with a Tm (melting point) of 270 °C (518 °F). Syndiotactic polystyrene resin is currently produced under the trade name XAREC by Idemitsu corporation, who use a metallocene catalyst for the polymerisation reaction.

What are the chemical properties of polystyrene?

Polystyrene is relatively chemically inert. While it is waterproof, and resistant to breakdown by many acids and bases, it is easily attacked by many organic solvents (e.g. it dissolves quickly when exposed to acetone ), chlorinated solvents, and aromatic hydrocarbon solvents.

What is the process of converting polystyrene to styrene?

The process of depolymerizing polystyrene into its monomer, styrene, is called pyrolysis. This involves using high heat and pressure to break down the chemical bonds between each styrene compound. Pyrolysis usually goes up to 430°C.

What is the difference between polystyrene and expanded polystyrenes?

Polystyrene is commonly injection molded, vacuum formed, or extruded, while expanded polystyrene is either extruded or molded in a special process. Polystyrene copolymers are also produced; these contain one or more other monomers in addition to styrene.