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Another consequence of this effect is that at a relative vapor pressure, tends to
unity, RP is not infinitely dilute, and has a certain concentration.
Since at equilibrium chemical potential of water in these solutions are
equal, and the water activity bound water distribution constant Kd. Kd =
aw/aw,
where
aw
and
aw -
water activity in RP phases and NMS solution, respectively,
the resulting distribution of water is a constant value, showing how the water
activity in the Republic of Poland under the influence of the influence of her
plastic ties. Thanks to them, there is a limit RP lowest concentration that remains
constant with the addition of any amount of water. It is related to the fact that in
the polymer molecule the distance between the polar groups is fixed. This
distance depends on the nature of the polymer determines the minimum
concentration of RP.
Biopolymers - class of polymers, which occurs in nature in its natural
form. For example, as part of living organisms - proteins, nucleic acids,
polysaccharides, lignin. Biopolymers are composed of the same (or similar) units
- monomers. Monomers proteins - amino acids, nucleic acids - the nucleotides,
in polysaccharides - monosaccharides. There are two types of biopolymers -
regular (some polysaccharides) and irregular (proteins, nucleic acids,
polysaccharides number).
One of the promising directions in the field of polymer materials science is
the creation of new composite materials based on organic-inorganic systems of
different nature. Today, they are a separate class of composites, and their design
is given a lot of attention.
There are many methods for the synthesis of organic - inorganic materials
common of these are the sol-. Gel method based on hydrolysis reactions,
condensation alkoxides B
1
, T
1
, B, A
1
, V/, etc. with a functionality of 3 or 4 Use
of various classes of hydrophilic, hydrophobic polymers It allows you to receive,
a polymer matrix with micro- and with nanoscale inorganic inclusions.
Currently, the main focus in the research of organic-inorganic systems is to
obtain materials, the study of relaxation and physical-mechanical properties,
since they determine the area of application. Attention is paid to the optimization
phase structure, the choice of modifiers, defining the conditions of synthesis, to
regulate particulate composition and providing the necessary structural
organization.
The experience gained in the study of polymer composites showed that the
fundamental importance for solving the above problems has information on
phase equilibria, kinetics and mechanism of formation of the structure,
thermodynamics of interaction between the components and the degree of non
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