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The properties of ampholytic poly[N,N -dimethyl(acrylamido propyl) ammonium propane sulfonate] (poly(DMAAPS)) in aqueous solution were studied by measurements of cloud point determination and intrinsic viscosity. The minimum salt concentration and intrinsic viscosity of this polyampholyte were related to the type and concentration of added salt. Soft salt cations and anions bound more easily...
Methyl 2-(acyloxymethyl)acrylates [CH 2 C(CH 2 OCOR)COOCH 3 ; R = CH 3 , CH 2 CH 2 CH 3 , CH(CH 3 ) 2 and C(CH 3 ) 3 ] were prepared by nucleophilic substitution of methyl 2-(bromomethyl)acrylate with the desired carboxylic acid in the presence of triethylamine at ambient temperature. These particular monomers...
Wide-angle X-ray scattering (WAXS) and differential scanning calorimetry (d.s.c.) measurements were made on cellulose tributyrate (CTB). In one case, CTB precipitated from solution in powdered form was annealed at different temperatures. In a second case, CTB was isothermally crystallized either from the melt or from the glass. Samples annealed from the powder showed higher crystallinity with respect...
Unsaturated homopolyamide was prepared from 3-aminocinnamic acid (ACA) by the phosphorylation polycondensation method. In addition, various copolyamides were prepared from ACA and 4-aminobenzoic acid. Furthermore, an unsaturated homopolyamide was synthesized from 4-carboxycinnamic acid and 4,4 -diaminodiphenylmethane. The physical, chemical and thermal properties of the polyamides were correlated...
1H n.m.r. relaxation data, determined via either wide-line 1 H n.m.r. or high-resolution solid-state 13 C n.m.r., were used to analyse the existence and extent of interphasic regions in dimethylsiloxane-styrene block copolymers. Results thus obtained have shown that copolymers having very short blocks possess relatively large interphases characterized by intermediate mobility...
The structural changes in the uniaxial drawing process of an unoriented amorphous film of poly(ethylene naphthalene-2,6-dicarboxylate) (PEN) and in the heating process of an oriented amorphous film of PEN were studied using X-ray diffraction apparatus equipped with imaging plates. This apparatus allows us to record a time-resolved series of two-dimensional patterns of wide-angle X-ray diffraction...
The conditions for processing and doping of blends of poly(o-alkoxyaniline)s and poly(vinylidene fluoride) were investigated. Flexible, free-standing and stretchable films of blends of various compositions were obtained by casting. A low percolation threshold was observed with the onset of conductivity at low polyalkoxyaniline contents (i.e. 5%). Interestingly, these blends displayed electrochromism...
The difference in heat capacity of the liquid state and that of the glassy state at the glass transition temperature, ΔC p (T g ) = C p(1) - C p(g) , has been determined in samples of epoxy resin with different extents of cure. The epoxy was a diglycidyl ether of bisphenol A cured isothermally by phthalic anhydride as hardener in a temperature...
Motional heterogeneity in acrylate (AA)/laurylmethacrylate (LMA) copolymers was investigated by the two-dimensional 1 H- 13 C heteronuclear wideline-separation n.m.r. technique. Qualitative information about molecular dynamics is reflected in the width of the proton wideline. It was found that a decrease of the AA/LMA ratio in the copolymer reduces the packing density.
Stress-strain data have been obtained for poly(vinyl chloride) from drawing experiments in three stretching modes: uniaxial, planar and equibiaxial extension. The experiments were conducted isothermally at 84°C, which is in the glass transition region, and at 90°C, above T g . The stress-strain behaviour is qualitatively different at the two temperatures. At the lower temperature, there...
We have prepared and characterized several trithienylbenzenes. These compounds are used as reticulation points in poly(3-n-octylthiophene). It was necessary to study the reactivity of the reticulation points with regard to 3-n-octylthiophene. That is the reason why we have prepared copolymers starting from very high percentages of deuterated reticulation points (> 10%) and monitored their reactivities...
Interfacial polycondensation of 1,1 -diamino-4,4 -bipyridinium di-iodide, [H 2 N- + NC 5 H 4 -C 5 H 4 N + -NH 2 ]I 2 , with aromatic di- or tri-acyl chlorides, affords a novel class of hydrophilic polymers. These materials are isoelectronic with polyesters but contain ylid linkages [N + -N - -CO] in place of...
A stress-strain equation is studied which uses a non-Gaussian statistical mechanics model for large deformation of crosslinked rubbers. The formulation is based on the work introduced by Doi and Edwards for the description of polymer dynamics in a fixed network. The resulting constitutive equation is applied in the entire network of elastomers. Uniaxial and biaxial tensile and compressive experiments...
A range of hydrogel copolymer membranes of poly(2-hydroxyethyl methacrylate) with 4-vinylpyridine or 4-vinyl-4 -methyl-2,2 -bipyridine have been made and their permeabilities to a series of transition metal salts determined. Ion transport is characterized by an initial induction period prior to the onset of steady-state permeation. This period varies depending on the ion under study and can be...
Amphiphilic polymers with two different alternating functional units along the main chain were synthesized and their monolayer behaviour was investigated. When they have a ligand group adjacent to a carboxylic acid group, two different metal complexes can be introduced into a monolayer: a complex with a free coordination site can be bound via the ligand group, and a cationic complex as counter-ion...
The local dynamics of some model epoxy networks based on various diepoxides and diamines was investigated in the bulk state using high-resolution solid-state 13 C nuclear magnetic resonance. The strength of the 13 C- 1 H dipolar coupling was determined from the rises of 13 C magnetization in cross-polarization experiments using very short contact...
Two non-linear bead and spring models are considered for the Brownian dynamics simulation of the behaviour of polymer chains in a dilute solution under shear or elongational flow. One of them is the HYBRID model whose springs are Hookean at low elongation, and beyond some spring length they follow a Morse potential with a given dissociation energy. This model is suitable for studying polymer fracture...
A general measurement theory for determining the diffusion coefficient D of small molecules in polymer matrices is presented. This theory is applied to an arbitrary geometry of the polymer sample and an arbitrary initial penetrant content in the polymer. It is shown that one does not need to know specifically the dependence of the measured quantity on the concentration of the diffusing species,...
The microvoiding mechanisms and mechanical properties of a blend of poly(vinyl chloride) (PVC) with methyl methacrylate-butadiene-styrene (MBS) graft copolymers are investigated. It is found that the toughening effect is independent of the type of microvoiding mechanism occurring in the blend. Both internal cavitation of the MBS particles and debonding at the PVC/MBS interface relieve the triaxial...
The low-frequency Raman scattering (2-200 cm -1 range) of poly(methyl methacrylate) (PMMA) specimens plastically deformed in pure shear is compared to that of non-deformed specimens. The main experimental feature is an excess of Raman scattering in the 30-50 cm -1 spectral range induced by plastic deformation. This excess appears to be strongly anisotropic and is maximum...
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