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Polystyrene (PS) / ˌ p ɒ l i ˈ s t aɪ r iː n / is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene. [5] Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It is a poor barrier to air and water vapor and has a relatively low ...
Polymerization can be performed in large range of solvents (including water), within a wide temperature range, high functional group tolerance and absent of metals for polymerization. As of 2014, the range of commercially available RAFT agents covers close to all the monomer classes that can undergo radical polymerization.
Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) is a composite material where PEDOT (the conductive polymer) provides electrical conductivity, and PSS (polystyrene sulfonate) acts as a counter-ion to balance the charge and improve the water solubility and processability of PEDOT.
Addition polymerization differs from condensation polymerization, which does co-generate a product, usually water. [ 1 ] [ 2 ] Addition polymers can be formed by chain polymerization , when the polymer is formed by the sequential addition of monomer units to an active site in a chain reaction , or by polyaddition , when the polymer is formed by ...
In one copolymer, the monomers can be almost perfectly alternating. [1] but (random) copolymerisation with less than 50% maleic anhydride content is also possible. [2] The polymer is formed by a radical polymerization, using an organic peroxide as the initiator. The main characteristics of SMA copolymer are its transparent appearance, high heat ...
Free radical polymerization has found applications including the manufacture of polystyrene, thermoplastic block copolymer elastomers, [29] cardiovascular stents, [30] chemical surfactants [31] and lubricants. Block copolymers are used for a wide variety of applications including adhesives, footwear and toys.
In addition, some carbon nanotube polymer is used for electronical devices. Controlled living chain-growth conjugated polymerization will also enable the synthesis of well-defined advanced structures, including block copolymers. Their industrial applications extend to water purification, biomedical devices and sensors. [11]
In polymer chemistry, condensation polymers are any kind of polymers whose process of polymerization involves a condensation reaction (i.e. a small molecule, such as water or methanol, is produced as a byproduct). Natural proteins as well as some common plastics such as nylon and PETE are formed in this way.