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occurs in the system during its formation, the length of each of the large phase.
As a result conetworks exhibit two glass transition temperatures characteristic
for each of the components. In the case of IPN morphology of composite
material depends on the conditions of its reception. CHD often have a single
glass transition temperature, which occupies an intermediate value between the
two Tg polymers. And in the UPU holds a micro - or nano phase separation with
the formation of a significant amount of transition layers. When forming
successive UPU or semi-IPN domain size depends on the density of cross
linking of the first grid. The relevant sizes are determined conetworks MM
hydrophilic and hydrophobic moieties. In view of the above circumstances
conetworks crosslink density, size of the domains can be independently
controlled, whereas these parameters are related CHD.
In accordance with the terminology adopted in [26], conetworks, consisting
of disparate fragments, called amphiphilic. This term applies to AMS, bearing in
mind that in both cases the polymer system is required to include the hydrophilic
and hydrophobic moieties.
Amphiphilic conetworks - there are several ways to obtain this type of
structure. One - copolymerization of hydrophobic or hydrophilic
macromonomers with hydrophilic or hydrophobic monomers. Since the
macromonomer contains two polymerizable end groups, it also functions as a
crosslinking agent. Usually the copolymerization is carried out by a radical
mechanism in a solvent, providing homogeneity of the reaction mixture to start
the polymerization, carrying out a real or photoinitiation. According to this
technology conetworks prepared using hydrophobic macromonomers having
terminal methacrylate groups isobutylene based [59-61], propylene [62-64],
dimethylsiloxane [65-67], and others, as well as hydrophilic monomers such as
dimethylaminoethyl methacrylate [61]. 2-hydroxyethyl methacrylate [59, 60],
N, N -... dimethylacrylamide [68], etc. possible other embodiment, when the
macromonomer is the hydrophilic compound (PEO terminated methacrylate) and
monomers - hydrophobic or hydrophilic compounds (methyl methacrylate, butyl
acrylate, butyl methacrylate, methacrylic acid, etc.). [69-74].
For the synthesis techniques used conetworks "live" ionic polymerization.
The first stage of the process - the synthesis of amphiphilic block - copolymer
blocks to the desired size. In the second step the reaction mixture is introduced
into a polyfunctional crosslinking agent, which tearing somewhat "live" chain
provides cross-linking of the block - copolymer [75-77]. The advantage of this
method - the ability to precisely control the sizes of the hydrophilic and
hydrophobic moieties in conetworks.
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