الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The standard application of a chromatographic column is to use some
stationary phases to separate and quantitate the composition of organic
mixture. In the IGC method, the compositions of the stationary phase and the
solutes are known and thus, the interactions between them are determined.
Predominantly IGC has been used to determine the physico-chemical
properties (weight fraction activity coefficient, Flory- Huggins interaction
parameter, change in heat of adsorption (ΔH), change in free energy (ΔG),
and change in entropy (ΔS)) of stationary phases at infinite dilution. In the
case of polymer–solute systems this can be done using a column packed with
inert particles that have been coated with the polymer.
In our thesis, we aimed to establish a numerical study for interaction
of poly ethylene glycol (8000, 12000) [PEG8, PEG12], poly ethylene glycol
adipate [PEGA], and poly ethylene glycol succcinate [PEGS] with different
groups of solutes. Moreover, we also prepared a new polymer poly (styreneco-
p-chloromethylstyrene) [PS] with different properties and apply the
former study to invistigate the interaction of this new polymer with the same
group of solutes.
This study included the calculation of thermodynamic parameters,
weight fraction activity coefficient, Flory- Huggins interaction parameter.
from our finding, Specific retention volume Vg decreased as
temperature increased, as the interaction between the solutes and stationary
phase generally decreased by elevating the temperature. Vg increased also by
increasing the polarity of solute that interacts with polar polymer. This may
be explained in view of the nature of the polymer. Thus the solubility of
polar solutes is increased. This Leeds to longer retention time and, in turn,
SUMMARY AND CONCLUSION
95
higher calculated Vg for these solutes. The oppsite is true for non polar
solutes. Thus solubilities decreased leading to shorter retention time and
lower calculated Vg for non polar solutes.
It is well known, the smaller the ΔH, the greater is the interaction
between the solute and polymer.
ΔH gives us an impression about the interactions between the
polymer and solute, but its values for some solutes are near (e.g. ΔH of
carbon tetra chloride and n-hexane are -25.310 and -25.347, respectively).
So, we used Flory-Huggins interaction parameter for more clarifying of the
interactions between solute and polymer and to show which of solutes are
more miscible with polymer (as found in χ12 of carbon tetra chloride and npentane
that 0.051 and 2.214, respectively).
Flory-Huggins interaction parameter (χ12) reflects the interaction
between low-molecular-weight solvents and high-molecular-weight
polymers. Miscibility occurs when χ12 is lower than a critical value, or lower
than zero. Values lower than 0.5 indicate favourable interactions.
The weight fraction activity coefficient method, to gives us more
information about the interaction between solute and polymer. It devides the
solute interaction with polymer to a three groups (firstly, Ω∞
1<5 indicating
that the solute has a good compatibility with the polymer, the second is 5<
Ω∞
1<10 indicating that the solute has a moderate compatibility with the
polymer and the third is Ω∞
1>10 that indicate the poor compatibility between
the solute and polymer)
For PEG 12000 and PEG 8000, the physicochemical interaction
parameters showed that the two polymers has a good compatibility with
polar solutes as chloroform and carbon tetra chloride and a moderate
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96
compatibility with the polarizable solutes such as BTEX, but have apoor
compatibility with Alkanes, the physicochemical interaction parameters
showed also that PEG 12000 is more polar than PEG 8000 and shows strong
interactions with solutes higher than of PEG 8000. This phenomenon is due
the higher molecular weight of PEG 12000 than of PEG 8000, which thus
increase its polarity.
PEG esters (Adipate, Succinate) have the same performance of PEG
8000 and PEG 12000 except for Cyclo compounds, where these solutes
showed moderate polymer-solute interaction that help us to separate
aromatic, cyclo-alkanes and parafins (e.g. Ω1
∞ values of Toluene = 2.446,
Methyl cyclo hexane = 5.266, N.Heptane = 13.128) from a mixture of them
on gas chromatography, this behaviour due to its branched polymer. Also,
from the physicochemical interaction parameters we observed that PEGS
shows strong interactions with solutes higher than of PEGA. This
phenomenon is due the higher polarity of PEGS than PEGA
We developed a new stationary phase by preparing poly (styrene-cop-
chloromethylstyrene) and confirmed its structure using NMR which
displayed seven peaks, the peaks at 0.8 ppm and 1.2 ppm that assigned to the
terminal groups form each side as depicted on the structure. The peaks at 1.5
ppm and 2 ppm can be attributed to CH2 groups in styrene moiety and in pchloromethylstyrene
respectively. Two peaks attributed to CH of styrene and
p-chloromethylstyrene can be seen at 2.5 ppm and 3.3 ppm. The most
important peak that elucidates the formation of the copolymer comes from
the methylene group in p-chloromethylstyrene since it appears at 4.2 ppm.
IR that used for functional group determination, strong peak is
displayed at 3026 cm-1 which is characteristic for asymmetric stretch of
C=C-H on aromatic ring. The peak at 2923 cm-1 is attributed to the (CH)
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97
group that link monomer units to give polymer chains. A very important set
of peaks appear from 1744 to 1943 cm-1. These peaks are due to the
substituted aromatic rings in the polymer.
Thermal Gravimetric Analysis showed that the polymer has a good
thermal stability where, it decomposed at T= 400oK.
Also, GPC informed us that average molecular weight of polymer is
(58,550 g/mol).
The physicochemical interaction parameters of PS showed that, the
highest values of the Flory–Huggins interaction parameter for nonpolar test
solutes, n-alkanes. These high values reflect the poor
compatibility/miscibility of n-alkanes with the examined polymer. That was
confirmed by the values of weight fraction activity coefficient.
For polar test solutes, χ∞
12 values are lower than those for nonpolar
solutes reflecting the good miscibillity of them on PS, which appeared in
Cyclohexane and Methyl cyclohexane because of its cyclic formula.
Also, polarizable aromatic compounds, oxocompounds (Ketones,
Esters, and Ethers) and pyridine have a good compatibility with polymer
Generaly; the poly (styrene-co-p-chloromethylstyrene) can be
successfully used in the separation of different polar families as Aromatic
hydrocarbons, Cyclo-compounds, Esters, Ethers and Ketones by gas
chromatography.