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Showing 1 to 15 of 15 for “"branched polymer"”.
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Single molecule studies of branched polymer dynamics
Polymer architecture plays a major role on the emergent physical and chemical properties of materials such as elasticity and wettability. Branched polymers exhibit strikingly different rheological behavior (e.g. enhanced stress dissipation and strain hardening) compared to linear polymers. In …
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Constitutive modelling of branched polymer melts in non-linear response
… thesis is concerned with modelling long chain branched polymer melts using the McLeish and Larson Pompom constitutive equations. Usually the non-linear terms in this model are fitted to uniaxial extensional data due its sensitivity to levels of branching, but in this thesis I will study a …
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Single molecule studies of branched polymer dynamics in non-dilute solutions
The macroscopic properties of polymers are dictated by their molecular architecture and microstructure. Branched polymers exhibit a multitude of distinct rheological phenomena, such as shear thinning and enhanced strain hardening, compared to linear polymers as a direct consequence of their …
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About the gel structure of lignin
… that lignin in wood exists as a gel (network polymer) of extremely low crosslink density or as an ungelled, branched polymer only. Delignification is therefore not controlled by degelation but rather by interaction with carbohydrates via covalent or hydrogen bonds and/or by physical entrapment …
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Glycogen metabolism in Lafora disease
Glycogen, a branched polymer of glucose, serves as an osmotically neutral means of storing glucose. Covalent phosphate is a trace component of mammalian glycogen and has been a point of interest with respect to Lafora disease, a fatal form of juvenile myoclonus epilepsy. Mutations in either the …
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Mechanism and kinetics of homogeneous catalysis
… specific rate constants involved in 1-hexene polymerization process catalyzed by a family of group IV single-site catalysts. The primary set of elementary reaction steps included initiation, normal propagation, misinsertion, recovery from misinsertion, monomer independent and dependent chain …
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Comparison of Silica Polyamine Composites and Crosslinked Polystyrene Resins
… A study aimed at understanding the nature of the polymer-surface interface in SPCs was undertaken. This study explored the influence of changing the structure of the silane linker between the silica surface and the polyamine on metal ion selectivity. It was found that substituting the more rigid …
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Comparison of Silica Polyamine Composites and Crosslinked Polystyrene Resins
… A study aimed at understanding the nature of the polymer-surface interface in SPCs was undertaken. This study explored the influence of changing the structure of the silane linker between the silica surface and the polyamine on metal ion selectivity. It was found that substituting the more rigid …
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Synthesis and supramolecular assembly of biomimetic polymers
… chemistry is the synthesis of macromolecules and polymers with precise shapes and architectures. Polymer microstructure and architecture strongly affect the resulting functionality of advanced materials, yet understanding the static and dynamic properties of these complex macromolecules in bulk …
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Reactive modification and crystallization behavior of foamed poly(butylene terephthalate)
… and optimizing the quality of the foamed polymer. Initially, the linear PBT polymer was reactively modified using a tri-functional epoxide in a batch mixer to produce a branched structure with a higher molecular weight (MW) and a broader molecular weight distribution (MWD) as evidenced by …
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Diffusion Of Gold Nanoparticles In Synthetic And Biopolymer Solutions
<p>Soft matter systems of colloidal particles, polymers, amphiphiles and liquid crystals are ubiquitous in our everyday life. Food, plastics, soap and even human body is comprised of soft materials. Research conducted to understand the behavior of these soft matter systems at molecular level is …
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Synthesis and characterization of liquid crystalline polyrotaxanes based on poly(azomethine)s
Polyrotaxanes are new polymers. Macrocyclic molecules, such as crown ethers, are threaded by linear or branched polymer chains. There is no covalent bond between the crown ethers and the polymer backbone. After the crown ethers are threaded onto the polymer backbone, both ends of the polymer can be …
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Bio-composites materials from engineered natural fibres for structural applications
… synthetic fibre reinforced petrochemical-derived polymer composites along with potential improvement in mechanical properties for natural fibre reinforced bio-derived polymer composites, have long been a motivation for further research and innovation in natural fibre composites. Harakeke and hemp …
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Linear, Branched and Crosslinked Polymers, Polyesters, Polyurethanes and Polymethacrylates Derived From Rotaxane Formation: Syntheses and Properties
… family of composite materials, polyrotaxanes, polymers containing rotaxane units, have interested scientists world wide in last few decades because of their new properties. Crown ethers have been widely used as the cyclic component in various polyrotaxanes. However, due to significant loss of …
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Advancing thermal field-flow fractionation for industrial polymer characterization
… its open channel design and ability to separate polymers and colloids. The applied field in an FFF technique determines the physiochemical properties by which the separation occurs. A well-established theory relates retention time to a retention parameter that is defined by the interaction …