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Polystyrene foam blows in the wind and floats on water due to its low specific gravity. It can have serious effects on the health of birds and marine animals that swallow significant quantities. [71] Juvenile rainbow trout exposed to polystyrene fragments show toxic effects in the form of substantial histomorphometrical changes. [72]
The product is polystyrene. As alkenes can polymerize in somewhat straightforward radical reactions, they form useful compounds such as polyethylene and polyvinyl chloride (PVC), [3] which are produced in high tonnages each year [3] due to their usefulness in manufacturing processes of commercial products, such as piping, insulation and packaging.
Merrifield Resin is a cross-linked polystyrene resin that carries a chloromethyl functional group. Merrifield resin is named after its inventor, Robert Bruce Merrifield (1984 winner of the Nobel Prize in Chemistry), and used in solid-phase synthesis. The material is typically available as white beads.
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.
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 ...
The composition and structural type of the copolymer depend on these reactivity ratios r 1 and r 2 according to the Mayo–Lewis equation, also called the copolymerization equation or copolymer equation, [7] [6] for the relative instantaneous rates of incorporation of the two monomers.
The easiest way to visualize the mechanism of a step-growth polymerization is a group of people reaching out to hold their hands to form a human chain—each person has two hands (= reactive sites). There also is the possibility to have more than two reactive sites on a monomer: In this case branched polymers production take place.
Expanded polystyrene foam (EPS or "styrofoam", white) is used in making insulation and packaging materials, such as the "peanuts" and molded foam used to cushion fragile products. Polystyrene copolymers are used in the manufacture of toys and product casings.