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The anionic polymerization of t-butyl acrylate was achieved by using ethyl vinyl ether functionalized carbanionic initiator. In this way, poly(t-butyl acrylate) macromer with vinyl ether functionality was obtained. The macromer structure was characterized with the aid of 1 H nuclear magnetic resonance spectroscopy and gel permeation chromatography.
Zinc salts of lightly sulfonated polystyrene ionomers (Zn-SPSs) are shown to be effective compatibilizers for blends of a wholly aromatic liquid crystalline polyester (LCP) with nylon 66 (PA66) and polycarbonate (PC). Zn-SPS is miscible with PC, PA66 and the LCP, though the origins of miscibility are different for the three binary blends. Zn-SPS and PA66 mix because of strong intermolecular attractive...
The influence of A-B diblock copolymers on coalescence in A:B blends has been studied by rheo-optical measurements and electron microscopy. Divergent criteria and experimental evidence appear in the literature on the block copolymer (BC) molecular weight (M W ) and volume fraction ( bc ) when the requirement is the BC to reside at the interface. In the present study the block...
High-resolution monochromated X-ray photoelectron spectroscopy (X.p.s.) (core line and valence band) was used to study poly(ethylene terephthalate (PET) as biaxially oriented crystalline film, spin cast amorphous film and amorphous polymer melt. On going from crystalline to amorphous PET the C 1s glycol component shifts +0.10 to +0.14 eV, relative to the aromatic and carboxyl components. We ascribe...
The steric effect of solvent molecules in the dissolution of polyacrylonitrile (PAN) from five different kinds of N,N-dimethylformamide (DMF) derivatives was studied using Raman spectroscopy and a laboratory constructed laser optical instrument. The dissolution behavior of PAN from solvents such as DMF, N,N-dimethylacetamide,N ,N-diethylformamide, N,N-dimethylcarbamylchloride, and N,N-dimethyltrichloroacetamide...
Propylene was homopolymerized with the ansa-metallocene Ph 2 C(fluorenyl)(cyclopentadienyl)ZrCl 2 /methylaluminoxane catalyst to a highly syndiotactic polymer using a constant set of parameters. The properties of the pure syndiotactic polypropylene (sPP) such as molecular weight, chain microstructure and melting point were investigated, and the morphologies of uniaxially oriented...
Low band gap conducting polymer poly(isothianaphthene) (PITN), which is usually considered to be insoluble and cannot be processed into film, has been prepared by dehydrogenation from its precursor polymer, poly(1,3-dihydroisothianaphthene), with sulfuryl chloride. It is found that the intermediate towards PITN is structure 2. Through propagation of structure 2, a quinoid type conjugated poly(isothianaphene)...
The compatibilizing effect of 50 diblock isotactic polystyrene-isotactic polypropylene (iPS-b-iPP), prepared from a sequential block copolymerization of styrene and propylene by using a NdCl 3 -modified Ziegler-Natta catalyst, was examined in isotactic polystyrene (iPS)-isotactic polypropylene (iPP) blends. As investigated by differential scanning calorimetry (d.s.c.), dynamic mechanical...
The rate at which chloroprene proliferates or polymerizes by the popcorn mechanism from the vapour has been measured by means of a McBain balance between the temperatures of 3°C and 45°C. First-order kinetics were found for growth over 2 or 3 days once an induction period was complete. The Arrhenius activation energy for the growth was found to be 38.4 ± 0.7 kJ mol -1 .
The changes of parameters of the unit cell of biopolymer poly(β-hydroxybutyrate) (PHB) during heating from room temperature to the melting temperature are measured and results are presented here. The considerable increase of value of parameter a with increase of temperature is noticed with coefficient of thermal expansion of ( 1.4 ± 0.3) 10 -4 °C -1 . In the same time...
Gas transfer through asymmetric polysulfone hollow fibre membranes has been modelled, allowing fine details of fibre structure to be deduced from gas permeation characteristics. The structural information is used to interpret the relationship between spinning conditions and fibre properties. Dope concentration determines the general morphology of the fibre, such as the porosity (voidage fraction),...
A new aromatic bismaleimide containing bis(phenoxy)naphthalene unit, 2,7-bis(4-maleimidophenoxy)-naphthalene, was synthesized from 2,7-bis(4-aminophenoxy)naphthalene and maleic anhydride by the usual two-step procedure that included ring-opening addition to give bismaleamic acid, followed by cyclodehydration to bismaleimide. The monomer was characterized by IR, 1 H-NMR, EA and mass spectrometry...
Polysulfide oligomers H(SC 2 H 4 OCH 2 OC 2 H 4 S) n H with n = 1-24 can be characterized by electrospray ionization mass spectrometry. Samples prepared by the conventional method are shown to contain up to eight series of oligomers differing in structure by one of a small group of variants in one (or sometimes two) of the repeat units, e.g. with one...
The effects of four low-profile additives (LPA), namely poly(vinyl acetate) (PVAc), poly(methyl methacrylate) (PMMA), thermoplastic polyurethane (PU), and polystyrene (PS), on volume shrinkage in the cure of unsaturated polyester (UP) resins at 110°C were investigated by the linear shrinkage method, density measurements, and dilatometry. Experimental results showed that, for the finally cured samples,...
Atomic force microscopy (AFM) and Fourier transform infra-red spectroscopy (FTi.r.) were used to investigate the nature of poly(ethylene terephthalate) (PET) films formed on the surface of a highly oriented poly(tetrafluoroethylene) (PTFE) substrate mechanically deposited on silicon wafers. PTFE films have been previously shown to be highly effective substrates for the growth of oriented overlayers;...
Polypropylene (PP) films with high β-crystal content were drawn biaxially under various conditions to obtain highly porous films. Their pore size distribution and pore volume, measured by the mercury intrusion method, were found to depend on the draw ratio. Wide-angle X-ray diffraction of the drawn films in edge view showed that the α and β crystals are oriented in directions parallel and perpendicular...
We have studied the reactions occurring in the solid state in phenol-formaldehyde systems crosslinked by a base. The results obtained with chemically defined models with Fourier transform infra-red spectroscopy and solid-state 13 C nuclear magnetic resonance spectroscopy (cross-polarization/magic angle spinning) applied the study of different resoles with variable formaldehyde/phenol...
The effect of a plastic deformation, induced by a simple shear, on the nanostructure of amorphous polycarbonate (PC), is studied by low-frequency Raman scattering (LFRS). As previously observed for poly(methyl methacrylate) (PMMA), an excess appears in the low-frequency part of LFRS spectra after plastic deformation. The excess is stronger in the case of PC than in the case of PMMA, and its light...
The new monomers, 2-(6-chloro-, 6-hydroxy-, 6-mercapto-, and 6-aminopurin-9-ylmethyl)-3,4-dihydro-2H-pyran (3a, 3b, 3c, and 3d, respectively) and 2-(6-chloro and 6-hydroxypurin-7-ylmethyl)-3,4-dihydro-2H-pyran (4a and 4b, respectively) were synthesized. Copolymerization of these monomers with maleic anhydride resulted in the alternating copolymers 5 and 7, which were hydrolysed to give poly[(2-(6-Cl-,...
This work deals with the swelling properties of polyethylene gels prepared from long precursor ethylene/ethylene methyl acrylate (EMA) and ethylene/ethylene vinyl acetate (EVA) copolymers by random cross-linking between the EVA and EMA monomers repeated along the ethylene chains. An n.m.r. approach is proposed to characterize the statistical structure of dry and swollen gels. A power law relationship...
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