ABSTRACT
A polymer is a long chain obtained from the repetition of small “monomer” units joined by covalent bonding. The first industrial process using chemically modified polymers was the invention of rubber by Goodyear in 1839, followed by the chemical modification of cellulose. In the 19th century, the absence of a well-defined transition for polymers led dogmatic chemists to throw polymers down the drain and not recognize them as pure compounds. Branched polymers have at least one skeleton to which side chains are grafted. The thickness of the adsorbed layer results from a competition between the attractive electrostatic interactions between polymer and substrate and the repellent steric force due to the entropic elasticity of the polymer chain. The basic separation principle of polyelectrolytes like DNA, consisting of circulating the polymers through obstacles or in a gel, is based on the model of reptation. A molecular millefeuille is a supramolecular assembly consisting of an alternation of layers of cationic and anionic polyelectrolytes.
