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Tacticity (from Greek: τακτικός, romanized: taktikos, "relating to arrangement or order") is the relative stereochemistry of adjacent chiral centers within a macromolecule. [ 1 ] [ better source needed ] The practical significance of tacticity rests on the effects on the physical properties of the polymer .
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 ...
Polystyrene is composed only of ... Tacticity describes the relative stereochemistry of chiral ... Traces of chlorine in the water supply attacked polymers ...
A polymer can be described in many ways: its degree of polymerisation, molar mass distribution, tacticity, copolymer distribution, the degree of branching, by its end-groups, crosslinks, crystallinity and thermal properties such as its glass transition temperature and melting temperature.
It is one of the most developed methods in chain-growth polymerization. Currently, most polymers in our daily life are synthesized by free radical polymerization, including polyethylene, polystyrene, polyvinyl chloride, polymethyl methacrylate, polyacrylonitrile, polyvinyl acetate, styrene butadiene rubber, nitrile rubber, neoprene, etc.
The molecular weight of the polystyrene blocks in the main picture is 102,000; the inset picture has a molecular weight of 91,000, producing slightly smaller domains. SBS block copolymer schematic microstructure. Microphase separation is a situation similar to that of oil and water. Oil and water are immiscible (i.e., they can phase separate).
Chain shuttling polymerization is a dual-catalyst method for producing block copolymers with alternating or variable tacticity.The desired effect of this method is to generate hybrid polymers that bear the properties of both polymer chains, such as a high melting point accompanied by high elasticity.
Polyacrylic acid (PAA) and polyacrylamide are obtained by radical polymerization in water solution and used as thickeners, adhesives or flocculants. Acrylate and methacrylate homo- and copolymers are made by radical polymerization in toluene-acetone for coating applications.