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The use of structural core/shell latex particles as toughening agents provides a model system which allows independent control of several key factors that influence the fracture toughness of modified plastics. This paper focuses on varying the shell composition of poly(butadiene-co-styrene) [P(B-S)] core/poly(methyl methacrylate) (PPMA) shell particles by incorporating acrylonitrile (AN) comonomer...
A novel analysis was carried out for static light scattering data to determine the molecular weight, M, and mean square radius of gyration < s 2 > of large molecular weight polymers. The analysis is based on the finding that the Debye scattering function P(x) for random flight polymer chains withx = (4πn/λ) 2 < s 2 > sin 2 (θ/2) can be numerically approximated...
The relationship between mechanical properties and phase morphology of blends of polyamide6 (PA6) and polycarbonate (PC) compatibilized with a maleic anhydride functionalized poly[styrene-b-(ethylene-co-butylene)-b-styrene] triblock copolymer (SEBS-gMA) were explored. The in situ chemical reaction between the maleic anhydride of SEBS and the amine end group of PA6 during melt mixing induces the encapsulation...
Ring-chain equilibration reactions of poly(decamethylene adipate) (PDA) were carried out in the presence of large amounts of diluent. Good yields of cyclics [CO(CH 2 ) 4 COO(CH 2 ) 10 O] x were obtained virtually free of linear species. The individual cyclics with 18-198 skeletal bonds were completely resolved using PL-gel mixed-E gel permeation chromatographic...
Positron annihilation lifetime spectra on polystyrene (PS) have been measured as a function of pressure relaxation time (t = 0-100 h) under the initial uniaxial pressure P = 0, 25 and 50 MPa, respectively. In order to extract the information on the variations in the microstructure and free-volume hole as a function of pressure relaxation time t, we first considered the inhibition of ortho-positromium...
The relation between the error in interdetector volume determination and peak spreading was studied for a polymer sample whose molecular weight distribution obeys the log-normal function. A compensation of these quantities was shown, i.e. their values were found for which the ratio of weight- to number-average molecular weight, M w /M n , was constant. The influence of non-uniformity...
Scanning force microscopy (SFM) was successfully used to study the microstructures of acrylic polymer-silica nanocomposite surfaces processed by the sol-gel method. We observed excellent flatness of the dip-coated nanocomposite surfaces (root mean square roughness = 0.345 nm; mean roughness = 0.270 nm), probably due to the levelling effect of the dipping solution. SFM revealed that acrylic polymer...
Fatigue processes in injection-moulded blends of polypropylene (PP) and a liquid-crystalline polyester (LCP) were investigated with reference to variations in the inner microstructure and the dynamic viscoelastic properties under cyclic tensile loading. For neat PP, whitening caused by inter-spherulite and/or interlamella microcrazing was observed over a wide range within the specimen, and the storage...
The catalytic effects of polyzwitterions on aqueous inter-ionic reactions were studied through the analysis of the influence of a representative zwitterionic macromolecule, poly[diethyl-(2-methacryloyloxyethoxy-2-ethyl)-1-(3-sulfopropyl) ammonium betaine], on two model inter-anionic and inter-cationic reactions, i.e. oxidation of ferrocyanide by persulfate and aquation of a bromopentaamminecobalt...
Poly(2-vinyl pyridine-b-styrene-b-2-vinyl pyridine) BAB type block copolymers were synthesized by anionic living polymerization. The micelle formation of these BAB type triblock copolymers was carried out in toluene and toluene/cyclohexane mixture, and estimated with dynamic light scattering for the polymer solutions. Poly(2-vinyl pyridine) sequences in core part of the polymer micelles of the BAB...
Ten homopolymers and 15 copolymers of poly(amide-sulfonamide)s were synthesized by low-temperature solution polycondensation of five different diamines with isophthalopyl chloride/terephthaloyl chloride inN,N -dimethylacetamide. The general reverse osmosis (RO) performance of these new membrane materials were investigated by a systematic screening test with 270 ppm nickel ion industrial waste as...
A novel norbornadiene polymer having optically active pinanyl groups in the pendant groups was synthesized as an optical resolution membrane material. The resulting polymer membrane showed highly enantioselective permeability for racemic propranolol used as a medicine. The permeability of tryptophan was much higher than that of a (+)-poly{1-[dimethyl(10-pinanyl)silyl]-1-propyne} membrane we reported...
Starting with poly(l-lactic acid) (PLLA) of molecular weight 330 000, fibres were obtained through a two stage process: (i) melt-extrusion at various collecting rates (ranging from 1.8 to 10 m min -1 , and (ii) hot-drawing at various drawing rates. The molecular weight of PLLA fell to about 100 000, as a consequence of the production process. Ninety per cent of the molecular weight...
One-step extrusion proved to be an innovative technique for the production of poly(ethylene terephthalate)/bisphenol A polycarbonate (PET/PC) compatible blends and copolymers by transesterification in the presence of a small amount of catalyst which was mechanically dispersed on the polymers before their extrusion. This method provides possibilities for producing a variety of polymeric materials...
Influences of butadiene rubber (BR) on the structure and mechanical properties of poly(vinyl chloride) (PVC)/low density polyethylene (LDPE) blends and its synergism with crosslinking agent have been studied. As a solid phase dispersant, BR can promote the phase dispersion of PVC and LDPE, but cannot improve their interfacial adhesion. While dicumyl peroxide (DCP) can initiate the co-crosslinking...
Polymaleamides from bisisomaleimides and diamines have been prepared by ring-opening polyaddition. These polymaleamides were found to have inherent viscosity in the range 0.30-0.42 g dl -1 . The identities of the polymaleamides were confirmed by elemental analysis, and i.r., u.v.-visible and 1 H n.m.r. spectoscopies. The thermal degradation behaviour of the polymaleamides was...
Measurements of swollen end-linked PDMS gels by means of small angle X-ray and neutron scattering are reported. Hexane and octane were used as solvents. The usual excess scattering associated with frozen-in elastic constraints is observed in the small Q region of the spectra. Contrast variation shows the gels to be chemically homogeneous. In the extended Q range explored, the observed structure...
Two-dimensional magic angle spinning (2D-MAS) 13 C n.m.r. spectroscopy and FTi.r. microscopy have been used to measure the orientation in uniaxially drawn film as a function of draw ratio. Results obtained agree well with those obtained by optical birefringence measurements. FTi.r. microscopy is a powerful method for mapping the orientation across the film thickness with quick data...
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