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The crosslinking process of PE and EVA with different concentrations of a crosslinking agent (CA) has been studied. The extent of the crosslinking has been evaluated by gel fraction and density measurements. The different transitions involved in the thermal processing and decomposition have been studied by DSC and TGA and compared for all the mixtures prepared. Mechanistic pseudo-kinetic models have...
The morphology and thermodynamic stability of crystals of isotactic polypropylene (iPP) were analyzed as a function of the path of crystallization by atomic force microscopy (AFM) and differential scanning calorimetry (DSC). Samples were melt-crystallized at different rates of cooling using a “controlled rapid cooling technique”, and subsequently annealed at elevated temperature. Mesomorphic equi-axed...
A novel photodegradable polystyrene-grafted-TiO 2 (PS-g-TiO 2 ) nanocomposite was prepared by embedding the grafted-TiO 2 into the commercial polystyrene. Solid-phase photocatalytic degradation of the PS-g-TiO 2 nanocomposite was carried out in ambient air at room temperature under ultraviolet lamp and/or sunlight irradiation. The properties of composite film were compared...
Linear α,ω di-epoxide-terminated poly(ethylene glycol) of molar mass 4000gmol −1 was end-linked with amine-terminated poly(amidoamine) (PAMAM) dendrimers of generations 0, 2, and 4 in water to prepare architecturally well-defined copolymer hydrogels. The gelation and equilibrium swelling of the gels in water were characterized while systematically varying the polymer concentration at preparation,...
There is a continuing need to produce polymer films with high optical clarity with ability to dial in the optical properties including refractive indices and optical anisotropies. In this research, we investigated the mechano-optical behavior of PMMA/PHB-Cl blend films during uniaxial deformation and mapped out the composition-birefringence-processing relationships. The results indicate the presence...
(R)-(−) (1) and (S)-(+)-2-(3′-Thienyl)ethyl N-(3″,5″-dinitrobenzoyl)-α-phenylglycinate (2) monomers were synthesized, characterized, and polymerized in chloroform using FeCl 3 as an oxidizing agent. Molecular weights of 2.6×10 4 and 3.2×10 4 for poly1 and poly2, respectively, were determined by SEC analysis. FTIR spectra of the polymers indicated the coupling of monomers through...
A new bio-based elastomer synthesized from soybean oil was filled with nanoclay to generate an elastic nanocomposite. A solubility parameter study was used to select the organoclay for poly(acrylated oleic methyl ester) (AOME). Effects of the nanoclay on the macroscopic and microscopic properties were explored. The morphology varies from fully exfoliated to intercalated structure with different types...
A series of amphiphilic hyperbranched polymers with a polyester–polyol core and 64 terminal hydroxyl groups were modified by substituting various terminal groups: alkyl tails, amino, and carboxyl groups. The effect of the pendant groups' chemical composition on the resulting surface morphology within Langmuir–Blodgett monolayers with respect to their ability to form nanofibrillar surface structures...
Original natural triol (castor oil) was used as a monomer for the synthesis of monodisperse polyurethane nanoparticles (size ranging from 200 to 400nm) by miniemulsion technique in water. Various parameters such as the concentration of the reactants, the nature of stabilizers and the shear were tuned to control the particle size and its distribution. The polyaddition between the natural triol and...
Core–shell–corona micelles with a thermoresponsive shell self-assembled by triblock copolymer of poly(ethyleneglycol)-b-poly(N-isopropylacrylamide)-b-polystyrene (PEG 45 -b-PNIPAM 168 -b-PS 46 ) are studied by 1 H NMR, light scattering and atomic force microscopy. The thermoresponsive triblock copolymer, which has a relatively short hydrophobic PS block, can disperse...
Holographic polymerization (H-P) has been used to fabricate polymer-dispersed liquid crystals and pattern inert nanoparticles. In this article, one-dimensional grating structures of Norland resin and polyethylene glycol (PEG) were achieved using the H-P technique. Both reflection and transmission grating structures were fabricated. The optical properties of the reflection grating structures (also...
Novel, highly functionalized rod-like copolymers have been synthesized by alternating copolymerization of N,N,N′,N′-tetraalkyl-4,4′-diaminostilbenes (TDASs) with maleic anhydride. These unique copolymers have been characterized by SEC, DSC and TGA. The solubility of these copolymers in organic solvents is strongly dependent on the length of the alkyl chains on the amino groups and the solubility in...
In recent years, polymer microcapsules have attracted more and more attention because of their specific properties and applications in encapsulation and drug delivery. Great effort has been made to investigate the preparation methods, structure controls as well as the property designs for the polymer microcapsules. In this work, we reported an effective route for the preparation of poly(β-hydroxybutyrate)...
Atomistic molecular dynamics simulations have been performed to investigate the effects of introducing monofunctional polyhedral oligomeric silsesquioxanes (POSSs) as pendant groups on the polymethyl methacrylate backbone. The effect of POSS loading and of the structure of the organic substituents on the seven silicon atoms, isobutyl groups or cyclohexyl rings, was studied. Calculated volume–temperature...
For polymer/organoclay nanocomposites formed by melt processing, interactions between the polymer, montmorillonite surface, and surfactant determine any thermodynamic driving force for dispersion of the clay in the polymer. Interactions between poly(styrene-co-acrylonitrile) (SAN) and a single organoclay were probed by varying the SAN copolymer composition. Sample preparation was accomplished by melt...
A wide range of chiral amines and amino alcohols associate with poly(2-methoxyaniline-5-sulfonic acid) (PMAS) in aqueous solution, from which optically active PMAS·(amine) films can be cast. The chiral induction is believed to be initiated by acid–base interactions with “free” sulfonic acid groups on the PMAS chains. Chiral amine:PMAS dimer molar ratios as low as 1:4 give PMAS·(amine) films with similar...
The synthesis and surface properties of a 2×C 8 F 17 fluorocarbon di-functionalized poly(d,l-lactide), “F2PLA” are described. Small fractions ∼5%w/w of F2PLA, when blended with unfunctionalized poly(d,l-lactide), “PLA”, render the surface both hydrophobic and lipophobic. Contact angle analysis indicates that the properties of the blend surface approach those of PTFE. Rutherford backscattering...
Crystallization and structure formation of poly(ethylene oxide)–poly(ɛ-caprolactone) block copolymers (PEG–PCL) in which the melting temperatures of the components are close to each other were elucidated using differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) techniques. The diblock copolymers with 33, 46 and 59wt% of PEG composition...
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