Philippe Vroman

Ecole d'ingénierie et d'innovation textile | ENSAIT · GEMTEX Laboratory (Génie des Matériaux Textiles)

Flax fibre mats are promising and versatile biosourced reinforcements that can be used in composite parts obtained using various processing routes. To optimise their impregnation and the end-use properties of composites, it is crucial to better understand the process-induced evolution of their microstructure and their permeability. In this study, f...

Issues of fossil fuel and plastic pollution are shifting public demand toward biopolymer-based textiles. For instance, silk, which has been traditionally used during at least 5 milleniums in China, is re-emerging in research and industry with the development of high-tech spinning methods. Various arthropods, e.g. insects and arachnids, produce silk...

To date, nonwoven fabrics made with natural fibres and thermoplastic commingled fibres have been extensively used in the composite industry for a wide variety of applications. This paper presents an innovative study about the effect of the manufacturing parameters on the mechanical behaviour of flax/PP nonwoven reinforced composites. The mechanical...

Biodegradable natural fibre composites are increasingly developed for lightweight structural applications in automobile and construction industries with significant environmental benefit. This work aims to explore the sound and vibration properties of natural fibre composites that inevitably suffer menace of vibrations during their operations as en...

Currently, nonwoven fabrics made with natural and thermoplastic commingled fibers have been extensively used in the composite industry due to their light weight and low processing and material costs. As two key parameters in the manufacturing of nonwoven fabrics, the needle-punching and material surface densities influence strongly the mechanical p...

The bicomponent meltblown process offers to associate two polymers in the same fiber generating fibrous media with new properties. In this study, we associate polypropylene (PP) and poly(lactic acid) (PLA), from renewable sources, polymers. The influence of primary air flow rate and the structural properties of the PP/PLA bicomponent meltblown are...

A composite porous scaffold for bone cell culture was fabricated by immobilizing HA (hydroxyapatite) (Ca 10 (PO 4 ) 6 (OH) 2 ) microparticles on PLA (poly(lactic acid)) nonwoven fibers using the layer-by-layer deposition technique. A nonwoven PLA of thickness 1 mm, with average pore size of 230 µm and a porosity of 94%, was used. The nonwoven was f...

A microencapsulated flame retardant was used in order to produce a flame retardant nonwoven substrate. Melamine-formaldehyde polymer-shell microcapsules, containing Afflamit® PLF 280 (resorcinol bis(diphenyl phosphate)) as the core substance, were coated by an outer thermoplastic wall (polystyrene (PS) or poly(methyl methacrylate)), before being ap...

A microencapsulated flame retardant was used with the intention to produce flame retardant nonwoven substrate. Melamine-formaldehyde polymer-shell microcapsules, containing Afflamit® PLF 280 (Resorcinol Bis( Diphenyl Phosphate), a non-halogen flame retardant additive) as core substance, were coated by an outer thermoplastic wall (polystyrene (PS) o...

The development of spunbond bicomponent island-in-the-sea (I/S) fibers with fracturation and fibrillation by high-pressure water jets is here presented as an alternative way (water and solvent free) to produce synthetic filtration media with submicron fibers at high production capacity. This study relates the key factors for the development of such...

In depth filtration, a challenge is to obtain the highest dust holding capacity (DHC) reaching a critical pressure drop in order to improve the filter medium lifespan. Such property can be driven by the design of the fibrous structure. Indeed, various structural parameters and properties can influence the behavior of the fibrous filter medium and t...

This work relates the study of the durability of biocomposites based on a “non-durable” bio-sourced polymer (PLA) matrix and reinforced with flax fibres and the possibility to extend and even significantly improve this durability through the introduction of a reasonable percentage of “durable” bio-sourced polymer (PA11). The results show that the m...

Polyurethane (PU) based on castor oil, 4.4'diphenyl methylene diisocyanate and 1,3-propane diol was synthesized in two-steps. The composites were obtained by blending the PU with various amounts of cellulosic fibers extracted from the Moroccan Alfa stems (esparto grass plant). The influence of the cellulosic fiber ratio on the thermal and mechanica...

Flax fibers, available as fiber bundles, are commonly used as fiber reinforcement in composite materials as a substitute for glass fibers. Pre-treatments are often necessary for improving fiber-resin adhesion, and also to facilitate fiber elementarization, and to improve fiber ability to be implemented in mechanical processes limiting fiber damages...

In depth filtration, a challenge is to obtain the highest dust holding capacity (DHC) reaching a critical pressure drop increase in order to improve the filter medium lifespan. Such performance can be driven by the design of the fibrous structure. Indeed, various structural parameters and properties can influence the behaviour of the fibrous filter...

Cette étude porte sur des composites à filasse de lin et à matrice thermoplastique (PP, PLA, PA11) obtenus par thermocompression à partir de non-tissés aiguilletés. La caractérisation mécanique en traction a montré que ces composites sont anisotropes et que leur épaisseur influence la rigidité et la contrainte maximale. L’analyse par DSC et DMA des...

In air filtration, nonwoven materials are known to be pertinent structures for fine filtration and moderate pressure drop. In order to develop a filter that combines good permeability and high efficiency, it is important to identify the relevant structural parameters of the nonwoven. The main criteria studied in this paper are fiber fineness, solid...

Whether for health reasons or for comfort, the reduction of noise in our living spaces is a crucial issue. Nowadays, porous materials such as polyurethane foams or glass wool are still widely used to reduce the noise levels emitted in the fields of building and transport. However, these materials show a certain number of limits. Beyond the general...

In this paper, a computer aided system for designing nonwoven materials is presented. As an original approach in the field of nonwoven research, both quality measurement analysis and human knowledge processing are integrated in the system. It allows designers to optimize the structure of nonwoven materials with limited trials according to the funct...

This study aims at describing the microstructural deformation phenomena of flax fibre mats induced by changes in the relative humidity (RH) of the ambient air. At the macroscopic scale, the in-plane variations of the mats' dimensions were studied using a specially developed device. At the microscopic scale, in situ synchrotron X-ray microtomography...

Owing to various end-uses and good performance/cost ratio, the multifunctional textile materials have been significantly developed within a decade. Such materials are mostly dedicated to niche or limited markets and used for producing high-valued products. Facing the international competition, designers are strongly involved in the development of n...

This work is dedicated to develop an algorithm for the visual quality recognition of nonwoven materials, in which image analysis and neural network are involved in feature extraction and pattern recognition stage, respectively. During the feature extraction stage, each image is decomposed into four levels using the 9-7 bi-orthogonal wavelet base. T...

Previous work has shown that the uniformity recognition of nonwoven can be considered as a special case of pattern recognition. In this paper, a generalized frame for uniformity recognition based on computer vision and pattern recognition is introduced briefly. To validate the proposed generalized frame, a case study id carried out in experiment. I...

In this paper, the visual quality recognition of nonwovens is considered as a common problem of pattern recognition that will be solved by a joint approach by combining wavelet energy signatures, Bayesian neural network, and outlier detection. In this research, 625 nonwovens images of 5 different grades, 125 each grade, are decomposed at 4 levels w...

The surface uniformity recognition and inspection is an important and vital procedure of nonwoven production. Here, a novel approach for the uniformity recognition of nonwovens based on contourlet energy features and K-NN classifier is proposed. In this paper, the uniformity recognition based on contourlet transform and K-NN classifier is considere...

A novel system for the visual quality recognition of nonwovens is presented by combining wavelet texture analysis and K-nearest neighbor (K-NN) classifier and its numerical simulation is also illustrated. In this research, 625 nonwovens images of 5 different grades, 125 samples of each grade, are decomposed into 4 levels with wavelet base db8 and c...

The visual uniformity recognition of nonwoven materials using image analysis and neural network is a typical application of pattern recognition in textile industry. In this paper, we try to find a solution to this problem by combining the generalized Gaussian density (GGD) model in wavelet domain and two types of neural networks, robust Bayesian an...

Selection of relevant variables from a high dimensional process operation setting space is a problem frequently encountered in industrial process modeling. This paper presents two global relevancy criteria, which permit to formalize and combine the sensitivity of experimental data and the conformity of human knowledge using a liner and a fuzzy mode...

A joint method to identify nonwoven uniformity by combining wavelet transform, generalized Gaussian density (GGD) and generalized dynamic fuzzy (GDF) neural network is presented in this paper. Six hundred and twenty‐five nonwoven images of five different grades, 125 images of each grade, are decomposed at three different levels with coif4 wavelet b...

A set of intelligent decision support tools has recently been developed for specifically answering the complexity of multicriteria product design under strong constraints. These tools focus on selection of relevant design factors, determination of operation setting space meeting rapidly the desired quality specifications, and overall assessment of...

An approach to recognize the visual quality of nonwovens by combining wavelet texture analysis, Bayesian neural network and outlier detection is proposed in this paper. Nonwoven images (625) of five different grades, 125 of each grade, are decomposed at four levels with wavelet base sym6 and two energy-based features, norm-1 L1 and norm-2 L2, are c...

In this paper, an approach to grade nonwoven uniformity by combining wavelet texture analysis and learning vector quantization (LVQ) neural network is proposed. Six hundred and twenty-five nonwoven images of five different grades, 125 images of each grade, are decomposed at four different levels with five wavelet bases of Daubechies family, and two...

This paper deals with the potential of the hydroentanglement technique for structuring and consolidating a reinforcing structure based on natural fibres for composites. After reminding the principle, the interest of the technique is presented through two comparison studies. The first is related to a series of thermosetting composites obtained by re...

In the development of new industrial products, a classical design of experiments is often very expensive and time-consuming Consequently, this paper develops an original intelligent design support system for determining a relevant operation setting space and realizing a series of suitable prototypes in it This system permits a rapid convergence to...

Owing to various end-uses and good performance/cost ratio, the multifunctional nonwoven-based products have been significantly developed within a decade. Such products are mostly dedicated to niche or limited markets and are preferably high valued products. Therefore, in order to face the international competition, designers are strongly involved i...

The purpose of this work was to investigate how nonwoven fabrics absorb and diffuse liquids and to define relevant diffusion parameters, with a special focus on the influence of fiber diameter on the diffusion process. The nonwoven structures studied were composed of polyester fibers of different diameters and were manufactured with a drylaid/needl...

An approach to identify visual quality of nonwoven products by combining wavelet transform and learning vector quantization (LVQ) neural network is proposed in this paper. 625 nonwoven images of 5 different visual quality grades, each including 125 images, are decomposed at four different levels using five wavelet bases of the Daubechies family. Th...

In this paper, a computer aided system for designing nonwoven materials is presented. As an original approach in the field of nonwoven research, both quality measurement analysis and human knowledge processing are integrated in the system. It allows designers to optimize the structure of nonwoven materials with limited trials according to the funct...

Cette recherche a pour but d’étudier la faisabilité de matériaux composites à base d’alfa, en particulier pour la réalisation de prothèses orthopédiques. Elle entre dans le cadre d'un programme CMCU entre l'ENIT de Tunis et l'ENSAIT de Roubaix En phase préliminaire, l'extraction chimique a été mise au point en Tunisie. A l'ENSAIT, les travaux ont p...

Experiment design often involves multiple objectives and uncertain data in its optimizing process. Fuzzy multi-objective linear programming (FMOLP) is an appropriate method to handle this problem. For the case of modeling nonwoven-based resilient product experiment design, we first obtain the parameter values of objectives functions from a set of e...

Product prototype evaluation is an important phase in new product development (NPD). Such evaluation often requires multiple criteria that are within a hierarchy and a group of evaluators. The evaluation process and these evaluation criteria often involve uncertain and fuzzy data in the weights of these criteria and the judgments of these evaluator...