RSC Advances
Paper
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studies and morphology of epoxy resin reinforced with varying for 30 min at 30 C, further 1-chloro-4-nitrobenzene (0.08 mol)
weight percentages of POSS and cured with different diamines was added and reuxed at 100 ꢀC for 12 h and then cooled to 30
were compared with those of neat epoxy cured with diamino ꢀC. Further pale yellow solid product was obtained by quench-
diphenyl methane (DDM) and are discussed and reported.
ing the mixture with water. Aer thorough washing with water
and methanol, the yellow solid product was dried under
vacuum at 100 ꢀC to get 2,2-bis(4-(4-nitrophenoxy)phenyl)
propane.
Experimental
Materials
The puried 2,2-bis(4-(4-nitrophenoxy)-phenyl)propane (0.04
mol) was dissolved in ethanol (100 mL) and 10% Pd/C (0.250 g)
was added and reuxed at 50 ꢀC. Further, hydrazine mono-
The commercially available epoxy resin (diglycidyl ether of
bisphenol-A, DGEBA) LY 556 and 4,4-diaminodiphenylmethane
(DDM) were obtained from Ciba-Geigy Ltd., India. Bisphenol-A,
1,8-octanediol, 6-aminocaproic acid, 1-chloro-4-nitrobenzene,
potassium carbonate, N,N-dimethylformamide (DMF), ethanol,
Pd/C (10%) and hydrazine hydrate were obtained from SRL and
were used as received. The reinforcement POSS was synthesized
as per the reported procedure.9
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hydrate (25 mL) was added slowly and heated to 80–90 C for
another 3 h. The hot ltrate was allowed to cool to room
temperature, to obtain a white crystalline product (yield 85%,
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M.Pt 127 C) (Scheme S1c†).
Development of POSS reinforced epoxy composites cured with
different diamines
Synthesis of N,N0-(4,40-methylenebis(4,1-phenylene))bis(6-
The DGEBA epoxy resin 40 g and 1,3 and 5 wt% of POSS were
added separately and stirred for 24 h using a mechanical stirrer
and then a stoichiometric amount of diamine curing agent,
corresponding to epoxy equivalents was added. The ꢀresulting
product was poured into a pre-heated mould at 120 C for an
hour, to remove the moisture and trapped air. The samples were
cured successively cured at 120 ꢀC for 2 h, post cured at 180 ꢀC
for 3 h, and removed from the mould and characterized
(Scheme 1).
aminohexanamide)-(CPA)
In a 250 mL two neck round bottomed ask equipped with
condenser, 100 mL of N-methyl pyrrolidone (NMP), 10 g (0.0504
mol) of 6-aminocaproic acid, 13.2 g (0.1008 mol) of 4-(4-ami-
nobenzyl)benzenamine and a pinch of alkali hypo phosphate
catalyst were added. The reactants were allowed react at 100 ꢀC
for 24 h with efficient agitation to facile completion of reaction.
The product obtained was puried (yield 85%, M.Pt 124 ꢀC)
(Scheme S1a†).
Characterization
Synthesis of 1,8-bis(4-aminophenoxy)octane (OMA)
Fourier transform infrared (FT-IR) spectra for the samples were
recorded on a Perkin Elmer 6X FT-IR spectrometer. The 1H NMR
and 13C NMR spectra were recorded with a BRUCKER 300 MHz
NMR spectrometer. Samples were diluted using deuterated
chloroform (CDCl3), and tetramethylsilane (TMS) was used as
an internal standard. The glass transition temperature (Tg) of
the sample was determined using DSC 200 PC differential
scanning calorimeter (DSC) (Netzsch Gerateban GmbH). Ther-
mogravemetric analysis (TGA) was carried out using the DSTA
409 PC analyzer (Netzsch Gerateban GmbH). The surface
morphology of the fractured surface of the samples was exam-
ined using scanning electron microscope (SEM; JEOL JSM
Model 6360). A JEOL JEM-3010 analytical transmission electron
microscope operating at 80 kV with a measured point-to-point
resolution of 0.23 nm was used to characterize the phase
morphology of the developed nanocomposites. TEM samples
were prepared by dispersing powder samples under sonication
in ethanol and were mounted on carbon-coated Cu TEM grids
In a 250 mL two neck round-bottomed ask, 100 mL of dry N,N-
dimethylformamide (DMF), 23.2 g (0.4833 mol) of sodium
hydride (50%) and 10 g (0.161 mol) of 1,8-octanediol were
added. The reactants were stirred for 6 h at 50 ꢀC and cooled to
0–5 ꢀC to get the sodium salt of diol. Further, at the same
temperature, 50.7 g (0.322 mol) of 1-chloro-4-nitrobenzene was
dissolved in 100 mL of DMF. Aer the complete addition, the
temperature was raised to 30 ꢀC and stirred overnight. The
reaction mass was quenched into the required amount of
crushed ice, ltered, washed with distilled water and recrystal-
lized with ethanol to yield 1,2-bis(4-nitrophenoxy)ethane with
89% and the melting point of 134 ꢀC. Further the nitro
compound was reduced to yield out the diamine. 1 g of 10% Pd/
C was added to 10 g (0.3305 mol) of 1,2-bis(4-nitrophenoxy)
ethane dissolved in 100 mL of ethanol in a 250 mL round-
bottomed ask.
The reaction temperature was raised to 50 ꢀC. To the
mixture, then 20 mL of hydrazine hydrate was added and
reuxed for 3 h. The hot ltrate of the product was allowed to
cool to room temperature, to obtain a white crystalline product
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and dried for 1 h at 70 C to form a lm of <100 nm. Contact
angle measurements were carried out using 210 a Rame-hart
Inc. goniometer (Succasunna, NJ, USA) with 5 mL of deionised
water and diiodo methane (DIM).
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(yield 92%, M.Pt 120 C) (Scheme S1b†).
The dielectric studies were carried out with the help of an
impedance analyser, Solartron impedance/gain phase analyzer
1260 at RT using platinum (Pt) electrode at 30 ꢀC at a frequency
Synthesis of 4-(4-(2-(4-(4-aminosphenoxy)phenyl)propan-2-yl)
phenoxy)benzenamine (BPA)
To the 50 mL of N,N-dimethylformamide (DMF) in a 100 mL of 1 MHz this experiment was repeated four times at the same
ask dissolved bisphenol-A (0.04 mol) and aer the addition of conditions. X-ray diffraction patterns were recorded at room
potassium carbonate (0.12 mol) the reactants were stirred well temperature, by monitoring the diffraction angle 2q from 10 to
45434 | RSC Adv., 2014, 4, 45433–45441
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