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Showing 1 to 12 of 12 for “"Nucleating agents"”.
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Molecular modeling of polymer crystallization and the effect of nucleating agents
… presents the first computational screening of nucleating agents for macromolecular crystallization. Screens were conducted for two families of crystal materials: tetrahedrally coordinated materials isomorphic to diamond and silicon, and 2D, hexagonally coordinated materials isomorphic to …
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Supramolecular polymer additives to improve the crystallization behavior and optical properties of polybutylene terephthalate and polyamides
… and spherulite size, which can be controlled by nucleating agents. These additives can increase the crystallization temperature and thus reduce cycle times during melt processing, affect the physical properties and can in some cases improve the optical properties (clarity and haze). This thesis …
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Fully-renewable and degradable thermoplastic elastomers.
… the investigation of stereocomplexed micelles as nucleating agents for PLLA. Quantifiable improvements in the nucleation efficiency of PLLA were observed when blending PLLA with PDLA-containing triblock copolymers. Finally, potential applications of these all-biorenewable triblock copolymers were …
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Heterogeneous nucleation in polymer crystallization
… electron microscopy. The effectiveness of the nucleating agent has been evaluated by the study of the interfacial layer between the polymer and the substrate of densely packed particles using light microscopy and by quantitative analysis of the DSC cooling exotherms, obtained from polymers with …
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Heterogeneous crystallisation of polyethylene terephthalate. A study of the influence of organic and inorganic additives on the rate of crystallisation of polyethylene terephthalate and the subsequent changes in morphology and mechanical properties.
… inorganic and organic additives as possible nucleating agents on the crystallisation behaviour of P. E. T. and the suosequent influence on the morphological and mechanical properties has been examined. Various methods of mixing(: the polymer and additive were investigated and a method …
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Relationship between the micromorphology and mechanical properties of semicrystalline polypropylene
… of composition, in essence a limited range of nucleating agents, and processing methods, and aspects of the micromorphology, dimensional control and the mechanical properties of polypropylene. Polypropylene, as a sernicrystalline polymer, represents a class of materials in which mechanical …
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Development of masterbatches for poly (ethylene terephthalate) with improved resistance to CO2 permeation
… observed that all the fillers applied acted as nucleating agents for polymer crystallisation in the polymer systems to which they were applied.
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Glass ceramics from a South African pulverised fuel ash
… the highly oriented microstructure that results. Nucleating agents can be used to obviate this. By providing sites for crystal growth in the bulk of the sample, they induce the crystallisation of fine grained ceramics with good mechanical properties. This study examines the effect of TiO₂, P₂O₅, …
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Understanding Heterogeneous Nucleation Mechanisms in Polyolefins
… additional tool is the use of additives called nucleating agents (NAs), that improve the rate at which small crystallites form and can even promote different crystal polymorphs over others. However, much of the current understanding of NAs is based on trial-and-error, with no predictive power. …
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Nanocomposite-based Lignocellulosic Fibers
… and LbL modified fibers are able to acts as nucleating agents, which cause an increase of the crystallinity of PP. Moreover, results from tensile and flexural strength, dynamic mechanical analysis and water absorption tests revealed that the material (PDDA or clay) at the terminal (outer) …
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Understanding the effect of nanofillers on the properties of polypropylene and glass fiber/polypropylene multiscale composites
… Both silica and GNP were found to be effective nucleating agents, significantly increasing the crystallization rate during isothermal crystallization and favoring the nucleation of the the β- phase, which manifests superior impact strength and toughness compared to the most common α-form …
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Study of poly (l-lactic acid)/poly (d-lactic acid) stereocomplex as nucleating agent for poly (l- lactic acid) crystallization
… thermomechanical properties. To investigate the nucleating effect brought by the PLA stereocomplex, samples of PLLA blended with different content of PDLA are prepared by the solution casting method. With different cooling rates (5, 15, 25 C/min), DSC non-isothermal crystallization experiments …