The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
We report the formation of an ionomeric network in a poly(l,d-lactide) hybrid nanocomposite, (PLDLA-HYB) during in-situ melt polymerization of l,d-lactide in the presence of magnesium/aluminum layered-double-hydroxide (LDH) without added catalyst.The effect of LDH mass loading and reaction time on molecular mass and yield of soluble poly(l,d-lactide) (PLDLA-SOL) present in the hybrid was investigated...
Shape memory in polymers is a process whereby mechanical energy is microscopically stored, and reversibly recovered within the polymer. Consideration of the viscoelastic and glassy dynamics necessary for each step of the process reveals key molecular characteristics that may improve performance, including a rigid polymer backbone with narrow molecular weight distribution between a low fraction of...
Novel PSMA-POSS nanocomposites were prepared, in which N-phenylaminomethyl polyhedral oligomeric silsesquioxane (POSS) was conducted as crosslink agent to incorporate to poly(styrene-co-maleic anhydride) (PSMA). POSS was introduced by one-step reactive solution blend in amounts of 1–30 wt%. FTIR measurement evidenced the occurrence of amidation reaction between the anhydride group of PSMA and the...
Thermal degradation of polyethylene terephthalate (PET) is accelerated in the presence of commercial organoclays, and this remains a challenge for the industry. While a high level of clay delamination is required in polymer nanocomposites, thermal degradation increases furthermore for highly exfoliated morphologies due to an increased exposure of the polymer matrix to silicate nanoplatelets. In this...
Nanocomposites made of a crosslinked polydimethylsiloxane matrix filled with silica beads were prepared by solvent-casting. The nanoparticle dispersion was tuned by changing the solvent. Three types of surface properties are investigated for the nanoparticles through surface grafting. Hydrophilic (unmodified), hydrophobic or carboxylic acid functionalized (allowing particle-PDMS covalent bonding)...
Carbon nanotubes have been extensively used in isotropic polymer media as mechanical reinforcements or as conductive fillers. New phenomena arise when the polymer matrix is made of an ordered block copolymer. Dispersions of nanotubes stabilized by block copolymers in selective solvents can be used to cast composite films in which the nanotubes are segregated in microdomains of the structured polymer...
This work reports that imidazolium-based ionic liquids (ILs) are very efficient solvents and catalysts for the selective synthesis of novel high performance polyamides (PAs) from a new diamine-bisphenol. Direct polycondensation of the diamine-bisphenol was carried out with various dicarboxylic acids by using mixture of: (1) triphenylphosphite (TPP)/N-methylpyrolidone (NMP)/pyridine (Py)/LiCl; and...
Multilayer coextrusion was used to disperse Carbon Nanotubes (CNT) in polypropylene (PP). The dilution of commercially available masterbatches using a twin-screw extruder was first applied to produce several formulations, which were then mixed with PP using a multilayer coextrusion device to obtain films or pellets with CNT concentrations between 0.1 and 1%wt. The influence of the specific mechanical...
Nanocomposites based on poly(ethylene succinate) (PES) containing different types of inorganic nanofillers, including graphene oxide, modified graphene oxide, multi-walled carbon nanotubes and silver nanoparticles at a concentration of 2.5 wt% were prepared by solution casting. Good dispersion of the nanomaterial in the polymer matrix was verified with SEM microphotographs. WAXD patterns showed no...
This paper explores the effect of nanoclay orientation on the long term thermal stability of a polyethylene (PE)/nanoclay nanocomposite. Nanoclay morphology and orientation in an injection molded PE–clay nanocomposite bar were examined using transmission electron microscopy and simultaneous small angle X-ray scattering (SAXS)/wide-angle X-ray diffraction (WAXD). These nanocomposites were aged at elevated...
The electrocaloric effect (ECE) is enhanced in ferroelectric relaxor terpolymer poly(vinylidene fluoride–trifluoroethylene–chlorofluoroethylene) (P(VDF–TrFE–CFE))/ZrO 2 nanocomposites. It was observed that the interface effects between the polymer matrix and nano-fillers enhance the polarization response and provide additional electrocaloric entropy changes. As a consequence, the nanocomposites...
Nanocomposites consisting of thermoplastic polyurethane–urea (TPU) and silica nanoparticles of various size and filler loadings were prepared by solution blending and extensively characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermal analysis, tensile tests, and nanoindentation. TPU copolymer was based on a cycloaliphatic diisocyanate and poly(tetramethylene...
Melt-spinning of layered double hydroxide (LDH)/high density polyethylene (HDPE) nanocomposites was reported for the first time. Initially LDH/HDPE nanocomposites were prepared by melt-mixing, in which clay loadings were up to 3 wt% while compatibilizer to clay ratio was kept to be 2:1. LDHs were hydrophobically modified by hexadienoic acid, tetradecanoic acid, and octadecanoic acid to overcome the...
Nanocomposite polymer and ultrathin film membranes have shown great promise in enhancing gas permeation and selectivity properties by interfacially straining polymer matrices, yielding structures of higher free volume. However, undesired particle aggregation and short temporal stability remain a big challenge. In the present study, an “inverse” architecture to conventional polymer nanocomposites was...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.