Chemistry Reference
In-Depth Information
cost of one kilogram of such polymer is 5-20 times larger than the cost
of usual constructional polymers (polycarbonates, polyamides, and poly-
formaldehydes). But, despite the high prices the polyesteresterketones and
compositions on their basis, owing to the high level of consumer charac-
teristics, find more and more applications in all industries. The growth of
production volumes is observed every year.
It is known, that the paces of annual growth of polyesteresterketones
consumption were about 25% before 1995, and its global consumption
in 1995 was 4000 tons. The polyesteresterketone do not cause ecological
problems and is amenable to secondary processing.
In connection with big perspectiveness of polyarylesterketones, the ex-
amining of the most popular methods for their production was of interest.
The literature data analysis shows that the synthesis of aromatic polyes-
terketones can be done by the acylation on Friedel-Crafts reaction or by
reaction of nucleophylic substitution of activated dihalogen-containing
aromatic compounds and bisphenolates of alkali metals [224, 229].
In the majority cases, the polyesterketones and polyesteresterketones
are produced by means of polycondensation interaction of bisphenols with
4,4′-dihalogen-substituted derivatives of benzophenone [230-263], gen-
erally it is 4,4′-difluoro- or dichlorbisphenylketone. The introduction of
replacers into the benzene ring of initial monomer raises the solubility
of polyesterketones and polyesteresterketones. So, polyesterketone on the
basis of 3,3′,5,5′-tetramethylene and 4,4′-difluorobenzophenone is dis-
solved at 25 °C [211-214] in dimethylsulfoxide, the reduced viscosity of
melt with concentration 0.5 gram/deciliter is 0.79 dL/g.
The polyesterketone based on 4,4′-dioxybenzophenone and dichlor-
methylenized benzene derivatives is soluble in chloroform and dichlo-
roethane [264]. The logarithmic solution viscosity of polyesterketone
obtained on the basis of 4,4′-dioxybisphenylsulfone and 4,4′-dichlor-
benzophenone in tetrachloroethane of concentration 0.5 gram/deciliter is
0.486; the film materials from this polyester (of thickness 1 mm) are char-
acterized by the high light transmission (86%) and keep perfect solubility
and initial viscosity after exposure to 320 °C during 2 h.
The high-boiling polar organic solvents - dimethylsulfoxide, sulfolane,
dimethylsulfone, dimethylformamide, dimethylacetamide - are generally
used for synthesizing the polyesterketones and polyesteresterketones by
means of polycondensation; in this case the reaction catalysts are the an-
hydrous hydroxides, carbonates, fluorides and hydrides of alkali metals.
