Lignin epoxy resins: synthesis and evaluation as coatings and composites

Epoxy resins are one of the most relevant and widely used thermosets in the market covering a wide range of applications. Industries are being forced to quickly transition towards sustainable alternatives due to the pressure from emerging environmental concerns, the depletion of petrochemical supplies, and compliance with environmental...

The Dalle de Verre Lantern of Liverpool Metropolitan Cathedral: Composition and In-service Behaviour of the Epoxy Resin Mortar

Arising from questions concerning the long-term stability of the mortar, this research establishes the composition of the epoxy resin mortar used for the construction of the dalle de verre lantern of Liverpool Metropolitan Cathedral. Water ingress had manifested itself early in the life of the lantern as a result of flaws in the mortar. These...

A multi-scale approach towards reusable steel-concrete composite floor systems

Traditionally welded headed studs have been used to generate composite interaction between a steel beam and a (cast in-situ) concrete floor. This permanent connection impairs the demountability of the structural components and therefore demolition of the composite floor system is inevitable at the end of the functional service life. The...

Cure-induced residual stresses for warpage reduction in thermoset laminates

The paper addresses the role played by the cure stage of a vacuum assisted resin transfer molding process in residual stresses generation. The Airstone 780E epoxy resin and Hardener 785H system broadly used in the wind turbine blade industry has been used in this study. The viscous–elastic properties of the resin have been characterized and...

Fatigue behavior of resin and steel reinforced resin used in IBCs

Injection Bolts have been preferred for several reasons over other alternatives for the rehabilitation of old riveted steel bridges since 1970’s. More recently they have been used to obtain slip critical shear connections in new structures such as new bridges, large roofs, storm barriers and other structures exposed to cyclic loading. In...

Mechanical properties of (steel-reinforced) resins used in injected bolted connections

This paper illustrates the most recent developments in the field of injected bolted connections. A novel injection material, steel-reinforced resin, is used to enhance stiffness of resin-injected bolted shear connections. The main goal is to achieve the slip resistance connection in a clearance holes without pre-tensioning of bolts. Steel...

A Multiphysics Numerical Framework for Epoxy Resins: Investigating Hygrothermal Ageing in Laminated Composites

Epoxy resins are increasingly used in critical structural components with widespread applications in the transportation, construction and energy industries. The wind energy sector is one of the fastest growing commercial markets for epoxy resins, meaning that the structural behaviour of epoxy resins is becoming a key area of research, especially...

Effect of Interfacial Polarization and Water Absorption on the Dielectric Properties of Epoxy-Nanocomposites

Five types of nanofillers, namely, silica, surface-silylated silica, alumina, surface-silylated alumina, and boron nitride, were tested in this study. Nanocomposites composed of an epoxy/amine resin and one of the five types of nanoparticles were tested as dielectrics with a focus on (i) the surface functionalization of the nanoparticles and (ii...

New Materials for Injected Bolted Connections: A Feasibility Study for Demountable Connections

The purpose of this thesis is to investigate the short- and long-term behaviour of injected bolted connections (IBCs) with oversize holes for various injection materials. A central theme in this thesis the demountability of IBCs, as a result of which several release agents are tested for their suitability in and effects on IBCs. <br/>Injection...

The use of polyurethane in coastal engineering models

In physical model tests there is often a need of preventing stones from moving. This can be achieved by gluing the stones. Applying PBA (Polyurethane Bonded Agregate, e.g. Elastocoast) guarantees no moving stones, a normal permeability and a transportable model.

Thermal and Electrical Properties of Nanocomposites, Including Material Properties

The research described in this thesis is part of a state-funded IOP-EMVT project in cooperation with industrial companies, aiming at the design, assessment and implementation of new, environmental friendly (e.g. oil and SF6 - free) solid dielectric materials. A large disadvantage of solid polymer dielectrics is their relatively low thermal...

Application of statistical methods for making maintenance decisions within power utilities

DSC measurements on experimental TGDDM/DDS resin systems: The influence of variations in resin composition and catalyst content

As part of an international cooperation programme, DSC measurements were performed on 17 resin mixtures, of which the basic constituents were TGDDM and DGEBA epoxies and DDS hardener. The DDS/TGDDM and DGEBA/TGDDM ratios were systematically varied. In addition, for some of the mixtures small amounts of catalyst (0.2 and 2 weight percent) were...

Determination of the resin content in DSC prepreg samples using thermal analysis techniques

Determination of the heat of reaction during the cure of the resin in carbon fibre reinforced epoxy prepreg using Differential Scanning Calorimetry resulted in considerable scatter with the measurements were done on prepreg samples. Differences in resin content between the DSC prepreg samples were suspected to be the main cause of the observed...

Tensile failure of unidirectional composite materials