Jan-Anders Edvin Maansson

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A novel thermoplastic composite preforming process has been developed. This thermoplastic programmable powdered preforming process (TP-P4) uses commingled glass and polypropylene yarns, which are chopped to a desired length and deposited onto a vacuum scre ...

Transparent hyperbranched acrylate nanocomposites were produced using different combinations of silica nanoparticles and silicon-based sol-gel precursors. The nanocomposites were processed using a dual-cure UV polymerization and condensation scheme. The vi ...

NiTi alloy wires were embedded during the infusion processing of woven carbon fibre reinforced plastic (CFRP) composite plates with the purpose to passively increase their damping. Two types of NiTi wires, having the same diameter of 203 mu m, were considered, one superelastic at room temperature, the other one martensitic. For the first one, a martensitic transformation was induced by applying a pre-strain of 2.5% before embedding the wires. The coexistence of austenite and martensite should provide dampin

The mechanical and damping properties of unidirectional (UD) and twill 2/2 flax fibre (FF) reinforced thermoset (epoxy) and thermoplastic (polypropylene (PP) and polylactic acid (PLA)) composites containing 40 vol% of fibres have been compared with those o ...

The development of a reactive pultrusion process is presented by considering the advantages of an in situ polymerisation of thermoplastic lauryllactam monomers. The specifics of the reaction injection unit, of the fibre-drying oven and of different pultrusion dies are given. Models were developed for the optimisation of the pultrusion process and for each processing step, namely: impregnation, polymerisation and cooling. Their individual influence on the overall pultrusion line speed was established. Heat t

In a moulding process, in particular in a bladder inflation moulding (BIM process) a thin walled mould is machined to the exact shape of the part to avoid any post machining of the part after stripping. The heating is performed in a liquid tin bath, used to dip the mould therein for fast heat transfer. Processing cycle times of less than 1 minute are reached.

Equilibrium phase diagrams in composition-conversion space have been calculated for stoichiometric blends of an epoxy resin with a diamine hardener and dendritic hyperbranched polymers, to which various numbers of epoxy groups have been grafted. An attempt has been made to incorporate both the effects of the polydispersity of the resin and the reactivity of the functionalized hyperbranched polymers. The results suggest that below the gel point, the resin-rich regions of the phase diagrams are only weakly af

Micron- and submicron-sized barium titanate (BaTiO3) particles, untreated and surface modified with aminopropyl triethoxy silane, were incorporated in poly(vinylidene fluoride-trifluoroethylene) to fabricate composites with up to 60 vol% of ceramic phase. ...

The dimensional stability of V-shaped composite parts made from polyamide-12/carbon fibre (PA12/CF) commingled yarn has been studied. An anisotropic, thermoviscoelastic material model was implemented in a finite element solver to predict the internal stresses induced during the processing of the composite. Excellent correlation was found between predicted and experimentally measured stress profiles for compression-moulded parts. The stresses were related to the dimensional stability of the parts after demou

Carbon-epoxy prepregs are generally used to form the skins of honeycomb sandwich structures used in aerospace or racing yachts. For some applications, it is desirable to increase the thickness of the skins. In order to achieve an ideal core pressure level during cure for maximal skin-core bonding, the issue of air extraction from the honeycomb cells through the skin during processing thus becomes critical, in particular if vacuum only processing is used. In the present work, partially impregnated prepregs,

The influence of hyperbranched polymer grafted polypropylene (PP-HBP) on the interfacial adhesion between fusion bonded bilayers of polypropylene (PP) and polyamide 6 (PA6) and on the properties of PP/PA6 blends was investigated. The interfacial adhesion between PP-HBP compatibilised bilayers was ten times higher compared to maleic anhydride grafted PP (PP-MAH) compatibilised bilayers. This is attributed to the higher diffusitivity and functionality of PP-HBP leading to the formation of more PP-PA6 copolyme

Using a rheometer coupled with a UV-light generator, a photo-rheometry set-up has been developed to study the viscoelastic properties of UV-coating systems during fast curing. Due to a high reaction rate, the viscoelastic properties have to be evaluated using a special procedure. This technique was found suitable to obtain reliable rheological data during the fast photo-reaction, allowing the determination of gel points occurring within less than 1 s.

The effects of the size (pseudo-generation number) and nature of end groups on physical and rheological properties were investigated for a series of hyperbranched polyesters based on an ethoxylated pentaerythritol core and 2,2-bis-(hydroxymethyl) propionic acid repeat units. The observed linear dependence of the melt viscosity on the molar mass in the high pseudo-generation-number limit indicated that entanglement effects were substantially absent. Moreover, the marked influence of end capping of the end gr

This paper describes the production of an adaptive composite by embedding thin pre-strained shape memory alloy actuators into a Kevlar-epoxy host material. In order to combine the activation and sensing capabilities, fibre Bragg grating sensors are also em ...

The thermomechanical response of a series of thermally activated shape memory polyurethanes (SMPUs), determined by dynamic mechanical analysis (DMA), has been adjusted by systematic modification of the molecular architecture. It is argued that the free rec ...

A novel liquid system has been developed to initiate the anionic polymerization of lactam-12. This system, containing both an activator and a catalyst, has the primary advantage over previous systems of permitting infinite storage of the reactant, and it avoids premixing of batches. The anionic species of the system were identified with matrix-assisted laser desorption/ionization time-of-flight measurements, and Fourier transforminfrared was used to measure the change in their concentrations during the poly

The invention relates to novel polymer-based microstructures, with outstanding shape accuracy and cost-effective processing. The novel polymers are based on hyperbranched macromolecules and enable remarkable property combination such as reduced shrinkage a ...

The fast photopolymerization of different multifunctionalacrylates was analyzed by means of photorheology.The materials studied included a penta/hexaacrylatemonomer and two different acrylated hyperbranchedpolymers. The sensitivity of the commercial rheome ...

Life cycle assessment (LCA) and manufacturing focused life cycle costing are used to evaluate the potential advantages of composites in automotive applications. The life cycle costs and environmental performance of several suitable lightweight polymer comp ...

We present the development of a low-temperature liquid composite moulding cure schedule that is compatible with the fabrication of shape memory alloy (SMA)–epoxy composite materials. With this process, the SMA wires do not need to be maintained in place wi ...

Jan-Anders Edvin Maansson

Chattez avec Graph Search

Consolidation of net-shape random fiber thermoplastic composite preforms

Superhard transparent hybrid nanocomposites for high fidelity UV-nanoimprint lithography

Passive damping of composites with embedded shape memory alloy wires

Damping of thermoset and thermoplastic flax fibre composites

Reaction injection pultrusion of PA12 composites: Process and modelling

Procédé de moulage à grande capacité

Phase separation in epoxy resin-reactive dendritic hyperbranched polymer blends

Effect of silane coupling agent on the morphology, structure, and properties of poly(vinylidene fluoride-trifluoroethylene)/BaTiO3 composites

Numerical Analysis of the Dimensional Stability of Thermoplastic Composites Using a Thermoviscoelastic Approach

Hybrid processing of thick skins for honeycomb sandwich structures

Tailored interfacial properties for immiscible polymers by hyperbranched polymers

A rheological characterisation technique for fast UV-curable systems

Rheological and physical properties of aliphatic hyperbranched polyesters

Smart composites with embedded SMA actuators and fibre Bragg grating sensors : activation and control

Influence of molecular architecture on the isothermal time-dependent response of amorphous shape memory polyurethanes

Initiation Mechanisms of an Anionic Ring Opening Polymerisation for Lactam 12

Hyperbranched polymer for micro devices

Photorheology of Fast UV Curing Multifunctional Acrylates

Assessing the life cycle costs and environmental performance of lightweight materials in automobile applications

Tailored processing of epoxy with embedded shape memory alloy (SMA) wires