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A new mechanistic kinetic model is presented for the cure behaviour of unsaturated polyester (UP) resins. The model is based on free radical polymerisation mechanism and the free volume concept. The quasi steady-state assumption for the free radical concentration is not used, and the decrease in initiator efficiency with conversion and radical trapping are modelled separately. The glass transition...
The measurement of tensile modulus of poly(N-isopropylacrylamide) (PNIPA) gel in the solution of NaCl, NaI, LiNO 3 and NaNO 3 was carried out. It was confirmed that the tensile modulus of PNIPA gel in the solution of salt depends on the volume of gel regardless of the kind and concentration of salts. This result leads us to the conclusion that the addition of salt effect only on the...
The products of the thermal degradation of polydimethylsiloxane (PDMS) are determined by the heating conditions, since two competing mechanisms are involved.Cyclic oligomers are formed in the low degradation temperature range and during slow heating in programmed degradation. This involves molecular splitting of oligomers from loop conformations of the PDMS chain favoured by its flexibility, and assistance...
This research studies the effects of RuO 4 exposure on various samples of poly(styrene) (PS). Transmission electron energy-loss spectroscopy (EELS) shows a decrease in the 7eV π-π* transition characteristic of aromatic rings in PS indicating that RuO 4 covalently alters aromatic character. Imaging and selected-area electron diffraction show that a layer of RuO 2 solid forms...
New C 60 covalently linked PPV derivatives containing carbazole moiety poly{(2,5-di-pentoxyl-phenylene)-1,4-diylvinylene-3,6-[9-(1-azafulleroid-pro pyl)carbazolenevinylene]} (PPV-AFCAR) were synthesized and characterized. The polymers containing different percentage of C 60 were obtained through the percentage of azido unit being controlled by the initial feed ratio. Cyclic...
We investigated the temperature dependence of the crystalline morphology in linear low density polyethylene by light scattering, small-angle X-ray scattering (SAXS) and oscillating-DSC. Optical anisotropy in the spherulite, defined by model calculation of the Vv scattering pattern, and the order parameter of crystal orientation within spherulite, estimated by sharpness of the Hv scattering profile,...
The novel water soluble antenna polyelectrolyte: poly[sodium styrene sulfonate-co-(4-acryolyloxyphenyl)-10,15,20-tritolylporphyrin] (PSSS-Po) was synthesised, and its photophysical and photochemical properties were studied. Solubilisation of the various molecular probes such as pyrene or perylene in aqueous solution of the PSSS-Po proved that the polymer chain adopts the compact conformation. The...
In the first stage, a series of aromatic diamine compounds such as 2-methoxy-5,4'-diaminodiphenyl ether (ODAOMe) and 2-trifluomethyl-4,4'-diaminodiphenyl ether (ODACF 3 ) were synthesized. These aromatic diamines and 4,4'-diaminodiphenyl ether (ODA) were then used to prepare copolyimides with 4,4'-oxydiphthalic anhydride (ODPA) and bicyclo[2.2.2]-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride...
The noncrystalline structures of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) copolymers were studied by variable temperature solid-state wide-line 1 H NMR and solid-state high-resolution 13 C NMR spectroscopy. It is found that at room temperature there exists a rich and rigid component in the noncrystalline region of PHB and PHBV. The...
New ion-conducting polymer composite films have been prepared, and their ionic conducting properties have been investigated. The polymer composite films are fabricated from partially phosphorylated poly(vinyl alcohol) with tetramethylammonium salt (P-PVA.Me 4 N + ) and poly(acrylic acid) (PAA) or poly(ethylene glycol) (PEG). For P-PVA.Me 4 N + /PEG composite films,...
Controlled molecular weight, linear, ortho- and para-cresol novolac oligomers have been synthesized by using calculated amounts of a monofunctional 2,6-dimethylphenol endcapping reagent. It was found that an excess of formaldehyde was needed to achieve the targeted molecular weights, thus suggesting that a dynamic equilibrium exists in these reactions whereby formaldehyde adds and eliminates from...
The interaction of a new hydrocarbon (HC) and fluorocarbon (FC) co-modified poly(acrylic acid), SA-1-FX14-1, with a HC nonionic surfactant, Np7.5, was investigated by rheological measurements. Its solution property was compared with HC or FC modified counterpart. It was found that the incompatibility between HC and FC groups in the micellization process was improved in the solution of SA-1-FX14-1...
Hydrophobically associating polyacrylamides (HAPAMs) or hydrophobically associating hydrolyzed polyacrylamides (HHAPAMs) are generally prepared by micellar copolymerization which leads to a blocky distribution of hydrophobes and drifted compositions. In the present study, a series of HAPAMs were prepared by direct N-alkylation of the amide groups of a parent polyacrylamide (PAM) in DMSO with alkyl...
Structural development of natural rubber during uniaxial stretching was examined by an in situ wide angle X-ray diffraction measurement using a synchrotron. During stretching, the amorphous part showed little change, i.e. an amorphous halo remained clear even at 500% strain. The fraction of induced crystals was very small, though a clear crystalline pattern was observed at 400% strain. Some polymer...
The crystal polymorphisms of the poly(butylene-2,6-naphthalate) (PBN) prepared by various thermal treatments in bulk state were investigated. Crystalline forms obtained from different thermal treatments were characterized using wide-angle X-ray diffraction (WAXD) measurements. The α-form crystal is obtained by annealing the quenched PBN sample in the solid state or by crystallizing from the static...
Three methods for the controlled synthesis of vinylmethylsiloxane-dimethylsiloxane copolymers have been explored. These methods were based on the anionic ring-opening polymerisation of 2-vinyl-2,4,4,6,6-pentamethylcyclotrisiloxane (VD 2 ) and on the copolymerisation of this monomer with hexamethylcyclotrisiloxane (D 3 ). All of them permit control of the molecular weight of the copolymer,...
A method for the chemical recycling of poly(carbonate) (PC) plastic wastes in the forms of bisphenol A (BPA) and 1,3-dimethyl-2-imidazolidinone (DMI) was investigated. Treatment with N,N'-dimethyl-1,2-diaminoethane (DMDAE) of PC pellets or PC wastes, derived from compact discs, in dioxane with/without a catalytic amount of base (e.g. Na 2 CO 3 0.5mol%) for a short period at 100 ...
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