Pierre-Etienne Bourban

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The fusion bonding of neat polypropylene (PP) has been investigated under non-isothermal conditions with different initial adherend temperatures, and the results compared with results from bonds prepared under isothermal conditions with identical adherend temperatures. The mode I critical strain energy release rate of the bonds, Gc, was measured using a double cantilever beam geometry with a constant crack opening displacement. The effect of the adherend temperature and the hold time are summarized in time-

Nucleus pulposus replacements have been subjected to highly controversial discussions over the last 40 years. Their use has not yet resulted in a positive outcome to treat herniated disc or degenerated disc disease. The main reason is that not a single imp ...

The mode I inter-laminar fracture toughness of advanced knitted textile composites was investigated. Two complex weft-knitted glass fabrics were selected for the study: a triple rib knit and a Milano knit were impregnated with a tough epoxy resin and tested using a double cantilever beam geometry. For both knitted composites, the influence of the growth direction was studied by investigating crack propagation in both the wale and course directions. The fracture toughness was quantified by determining the cr

In order to describe the different events occurring during the anionic polymerization of polyamide 12 (PA12), a general concept of a time, temperature, and transformation (TTT) diagram was established and related to reactive processing conditions. Polymerization kinetics were established, and it was found that the reaction was best described by an autocatalytic expression. Polymerization temperatures above and below the final polymer melting temperature were considered. Furthermore, the variation of the mel

The application of hydrogels as load-bearing biomedical components is often limited by their mechanical properties. Often an attempt to improve a hydrogel's stiffness is accompanied by a loss of toughness and swelling properties. In this work, we show that ...

Wood fibre reinforced polylactic acid (PLA) composite foams have been successfully produced using supercritical carbon dioxide. A significant increase of specific properties, both stiffness and strength, was achieved by adding 5-10 wt% wood fibres. The exp ...

As part of a broader effort to establish processing-structure-property relationships in PLLA/nHA, which is currently under consideration for bioresorbable scaffolds for bone repair, hot stage optical microscopy and differential scanning calorimetry have be ...

We report on the modeling of a photopolymerizable hydrogel and its application as a replacement of the interior of the intervertebral disc (so called Nucleus Pulposus). The hydrogel is initially injected in its liquid form and then photopolymerized via a s ...

The thermoforming of thermoplastic sandwich structures based on the same matrix polymer for the face sheets and the core requires precise temperature control both before and during forming. Two opposing requirements must be satisfied: the face sheets must be heated to above the glass transition temperature Tg of the polymer whereas the temperature of the core should not approach Tg in order to avoid the collapse of the foam cells. A numerical model was used to determine the optimal thermal parameters for th

Biocomposite hydrogels with carboxymethylated, nanofibrillated cellulose (c-NFC) powder were prepared by UV polymerization of N-vinyl-2-pyrrolidone with Tween 20 trimethacrylate as a cross-linking agent for replacement of the native, human nucleus pulposus ...

In clinical situations, bone defects are often located at load bearing sites. Tissue engineering scaffolds are future bone substitutes and hence they will be subjected to mechanical stimulation. The goal of this study was to test if cyclic loading can be u ...

The strength of fusion bonds between polyamide 12 plaques has been investigated as a function of processing conditions, using the double cantilever beam geometry to measure the mode I critical strain energy release rate, GC. Bonding was carried out using an instrumented press, which allowed systematic variation of the bonding time, the holding pressure, the interface temperature and the initial difference in temperature between the plaques. GC was generally found to increase with hold time and interface tem

Developing hydrogels with optimal properties for specific applications is challenging as most of these properties, such as toughness, stiffness, swelling or deformability, are interrelated. The improvement of one property usually comes at the cost of anoth ...

A model for the consolidation of thermoplastic composites reinforced with a warpknitted fabric was developed. The evolution of void content during composite consolidation achieved via film stacking was related to the processing parameters and the material properties. Since the knitting process results in local variations of fiber volume fractions even within a tow, the flow mechanisms are not identical to those occurring in homogeneously dispersed fibers. Two different types of micro-scale porosities were d

Flexural and torsional rigidity are important properties of skis. However, the flexural and torsional rigidity that lead to optimal performance remain to be established. In the present study, four pairs of slalom skis that differed in flexural and torsiona ...

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

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

Nonisothermally fusion bonded butt joints were prepared by overmolding thermoplastic elastomers (TPEs) onto isotactic polypropylene (iPP) inserts in order to investigate the effect of processing conditions on the bond strength and interfacial microstructur ...

Pierre-Etienne Bourban

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Non-isothermal fusion bonding of polypropylene

A photopolymerized composite hydrogel and surgical implanting tool for a nucleus pulposus replacement

Fracture toughness of weft-knitted fabric composites

Time-temperature-transformation diagram for reactive processing of polyamide 12

Photo-polymerization, swelling and mechanical properties of cellulose fibre reinforced poly(ethylene glycol) hydrogels

An Injectable Family Of Soft Tissue Hydrogel Adhesives For Knee Applications

Processing and Mechanical Properties of Novel Wood Fibre Composites Foams

Solidification behavior of PLLA/nHA nanocomposites

Multi-Scale Modeling Of Photopolymerization For Medical Hydrogel-Implant Design

Pre-Heating of Thermoplastic Sandwich Materials for Rapid Thermoforming

Biocomposite Hydrogels with Carboxymethylated, Nanofibrillated Cellulose Powder for Replacement of the Nucleus Pulposus

In vivo cyclic loading as a potent stimulatory signal for bone formation inside tissue engineering scaffolds

Fusion bonding of polyamide 12

Hybrid granular hydrogels: combining composites and microgels for extended ranges of material properties

A model for the consolidation of warp-knitted reinforced laminates

What static and dynamic properties should slalom skis possess? Judgments by advanced and expert skiers

Damping of thermoset and thermoplastic flax fibre composites

Reaction injection pultrusion of PA12 composites: Process and modelling

Initiation Mechanisms of an Anionic Ring Opening Polymerisation for Lactam 12

Morphology and interfacial strength of nonisothermally fusion bonded hard and soft thermoplastics