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To the biochemist, water is, of course, the only solvent worthy of
consideration, because natural macromolecules exhibit their
remarkable conformational properties only in aqueous media.
Probably because of these remarkable properties, biochemists do not
tend to regard proteins, nucleotides and polysaccharides as
polymers in the way that real polymer scientists regard methyl
methacrylate and polyethylene. The laws of polymer statistics
hardly apply to native biopolymers. Between these two powerful
camps, lies the No-man's land of water soluble synthetic polymers:
here, we must also include natural polymers which have been
chemically modified. The scientific literature of these compounds
is characterized by a large number of patents, which is usually a
sign of little basic understanding, of 'know-how' rather than of
'know-why'. Many of the physical properties of such aqueous
solutions are intriguing: the polymer may be completely miscible
with water, and yet water is a 'poor' solvent, in terms of polymer
parlance. ~kiny of the polymers form thermorever sible gels on
heating or cooling. The phenomena of exothermic mixing and
salting-in are common features of such systems: neither can be
fully explained by the available theories. Finally, the eccentric
behaviour of polyelectrolytes is well documented. Despite the lack
of a sound physico-chemical foundation there is a general awareness
of the importance of water soluble vinyl, acrylic, polyether,
starch and cellulose derivatives, as witnessed again by ~he vast
patent literature.
To the biochemist, water is, of course, the only solvent worthy of
consideration, because natural macromolecules exhibit their
remarkable conformational properties only in aqueous media.
Probably because of these remarkable properties, biochemists do not
tend to regard proteins, nucleotides and polysaccharides as
polymers in the way that real polymer scientists regard methyl
methacrylate and polyethylene. The laws of polymer statistics
hardly apply to native biopolymers. Between these two powerful
camps, lies the No-man's land of water soluble synthetic polymers:
here, we must also include natural polymers which have been
chemically modified. The scientific literature of these compounds
is characterized by a large number of patents, which is usually a
sign of little basic understanding, of 'know-how' rather than of
'know-why'. Many of the physical properties of such aqueous
solutions are intriguing: the polymer may be completely miscible
with water, and yet water is a 'poor' solvent, in terms of polymer
parlance. ~kiny of the polymers form thermorever sible gels on
heating or cooling. The phenomena of exothermic mixing and
salting-in are common features of such systems: neither can be
fully explained by the available theories. Finally, the eccentric
behaviour of polyelectrolytes is well documented. Despite the lack
of a sound physico-chemical foundation there is a general awareness
of the importance of water soluble vinyl, acrylic, polyether,
starch and cellulose derivatives, as witnessed again by ~he vast
patent literature.
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