Polymer blend

About: Polymer blend is a research topic. Over the lifetime, 18474 publications have been published within this topic receiving 437183 citations. The topic is also known as: polymer mixture & Polymerblend 或者 Polyblend.

Effects of organoclays on morphology and thermal and rheological properties of polystyrene and poly(methyl methacrylate) blends

Abstract: Morphology, thermal and rheological properties of polymer-organoclay composites prepared by melt-blending of polystyrene (PS), poly(methyl methacrylate) (PMMA), and PS/PMMA blends with Cloisite® organoclays were examined by transmission electron microscopy, small-angle X-ray scattering, secondary ion mass spectroscopy, differential scanning calorimetry, and rheological techniques. Organoclay particles were finely dispersed and predominantly delaminated in PMMA-clay composites, whereas organoclays formed micrometer-sized aggregates in PS-clay composites. In PS/PMMA blends, the majority of clay particles was concentrated in the PMMA phase and in the interfacial region between PS and PMMA. Although incompatible PS/PMMA blends remained phase-separated after being melt-blended with organoclays, the addition of organoclays resulted in a drastic reduction in the average microdomain sizes (from 1–1.5 μm to ca. 300–500 nm), indicating that organoclays partially compatibilized the immiscible PS/PMMA blends. The effect of surfactant (di-methyl di-octadecyl-ammonia chloride), used in the preparation of organoclays, on the PS/PMMA miscibility was also investigated. The free surfactant was more compatible with PMMA than with PS; the surfactant was concentrated in PMMA and in the interfacial region of the blends. The microdomain size reduction resulting from the addition of organoclays was definitely more significant than that caused by adding the same amount of free surfactant without clay. The effect of organoclays on the rheological properties was insignificant in all tested systems, suggesting weak interactions between the clay particles and the polymer matrix. In the PS system, PMMA, and organoclay the extent of clay exfoliation and the resultant properties are controlled by the compatibility between the polymer matrix and the surfactant rather than by interactions between the polymer and the clay surface. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 44–54, 2003

Polymer Composites: From Nano- to Macro-Scale

Abstract: Nano-Composites: Structure and Properties. Carbon nanotube reinforced polymers: a state of the art review.- Application of non-layered nanoparticles in polymer modification.- Reinforcement of thermosetting polymers by the incorporation of micro- and nanoparticles.- Polyimides reinforced with the sol-gel derived organosilicon nanophase: synthesis and structure-property relationships.- Layered silicate/rubber nanocomposites via latex and solution intercalations.- Property improvements of an epoxy resin by nanosilica particle reinforcement.- Special Characterization Methods and Modelling. Micro-scratch testing and FE contact and debonding analysis of polymer composites.- Determination of interface strength of polymer-polymer joints by a curved interface tensile test.- Manufacturing and characterization of microfibrillar reinforced composites from different polymer blends.- Tribological characteristics of micro- and nanoparticle reinforced polymer composites.- Macro-Composites: Processing and Application. Production of thermoplastic towpregs and towpreg-based composites.- Manufacturing of tailored reinforcements for LCM processes.- De-consolidation and re-consolidation of thermoplastic composites during processing.- LFT composites in automotive applications.- Mechanical Performance of Macro-Composites. Deformation mechanisms of knitted fabric composites.- Impact damage in composite laminates.- Discontinuous basalt fiber reinforced hybrid composites.- Accelerated testing methodology for durability of polymer composites.- Author index.- Subject index.

Strain hardening in polypropylenes and its role in extrusion foaming

Abstract: Extensional viscosity of several polypropylene polymers and their blends was measured and the foam processing of these blends using carbon dioxide blowing agent was studied. Foaming was carried out on a co-rotating twin-screw extrusion line, with a gear pump to build pressure. A linear isotactic polypropylene and two branched polypropylenes were considered. The uniaxial extensional viscosity was quantified and the foam characterized based on bulk density, cell size, and cell concentration. The linear polymer exhibits no strain hardening, while both branched polymers show pronounced strain hardening. Blends of low concentrations of branched polymer in the linear polypropylene show significant strain hardening down to 10-wt% branched polypropylene. Strain hardening is expected to prevent cell coalescence and lead to higher cell concentrations. The branched polymers were found to have a lower cell concentration than the linear polymer. Yet blends of linear and branched polypropylenes attained a cell concentration higher than either of the neat polymers. This suggests that even small amounts of branched polypropylene blended in linear polypropylene can improve the foaming process. Polym. Eng. Sci. 44:2090–2100, 2004. © 2004 Society of Plastics Engineers.

Layered surgical biocomposite material

Abstract: Biocomposite material that is especially suitable for bone surgical applications, containing: at least one bioceramic piece (1) (bioceramic component) and at least one material component (2). The material component (2) comprises at least reinforcement elements which have been manufactured of essentially resorbable material like polymer, copolymer, polymer mixture and/or ceramic material.