Capillary Infiltration Research Articles

Molecular Alignment of a Meta-Aramid on Carbon Nanotubes by In Situ Interfacial Polymerization.

Molecularly organized nanocomposites of polymers and carbon nanotubes (CNTs) have great promise as high-performance materials; in particular, conformal deposition of polymers can control interfacial properties for mechanical load transfer, electrical or thermal transport, or electro/chemical transduction. However, controllability of polymer-CNT interaction remains a challenge with common processing methods that combine CNTs and polymers in melt or in solution, often leading to nonuniform polymer distribution and CNT aggregation. Here, we demonstrate CNTs within net-shape sheets can be controllably coated with a conformal coating of meta-aramid by simultaneous capillary infiltration and interfacial polymerization. We determine that π-interaction between the polymer and CNTs results in chain alignment parallel to the CNT outer wall. Subsequent nucleation and growth of the precipitated aramid forms a smooth continuous layered sheath around the CNTs. These findings motivate future investigation of mechanical properties of the resulting composites, and adaptation of the in situ polymerization method to other substrates.

In situ observation of the capillary infiltration of molten silicon in a SiC/SiC composite by X-ray radiography

Capillary infiltration is an innovative fabrication method for metal and ceramic-matrix composites. SiC/SiC composites can be infiltrated by molten silicon to decrease residual porosity. Physical and chemical mechanisms involved during Liquid Silicon Infiltration (LSI) are complex to analyse. An in situ observation setup for capillary infiltration of molten silicon has been designed for synchrotron observations. The setup reproduces the extreme high temperature and high vacuum conditions used in the LSI process. It is also designed for X-ray observations in synchrotron beamlines and tomography stages. Sets of 2D X-ray absorption radiographs were acquired at high frequency during the LSI process. The study outlines the capillary infiltration mechanisms of molten silicon inside SiC/SiC composites. It proves that full saturation of the composite is not directly achieved after the rise of molten silicon. It is a two step mechanism. First, the infiltration occurs inside the intra granular porosity of the SiC powder matrix. Then, larger scale porosities such as cracks are filled. These phenomena have been discussed previously in the literature but never observed in situ.

Experimental study on the effect of three-dimensional porous structures on the vascularization rate of artificial dermis

Experimental study on the effect of three-dimensional porous structures on the vascularization rate of artificial dermis

Myocardial involvement in COVID-19: data from 102 unselected autopsies during the first wave of pandemic

Abstract Background Myocardial involvement in COVID-19 has been described as either coronary artery related ischemic lesions, lymphocyte myocarditis or microangiopathy. Assessment of the link between COVID-19 and the cause of death has been hampered by the limited number of autopsies performed during the pandemics and risk factors associated with the type and extent of myocardial damage remain poorly described. In Russia, the mandatory autopsy approach has been advocated for the cases of suspected COVID-19 related deaths. Purpose To describe the prevalence, extent and risk factors associated with myocardial damage in an unselected cohort of patients deceased with COVID-19. Methods Consecutive patients with PCR-confirmed or suspected COVID-19 who died either in-hospital (clinical autopsy) or out-of-hospital (forensic autopsy) during COVID-19 pandemic underwent post-mortem PCR on pulmonary parenchymal tissue. Tissue PCR-positive cases were referred for histology study of pulmonary and extrapulmonary organ specimens through a central laboratory. Based on the extent of diffuse alveolar damage (DAD), COVID-19 was categorized as either being related to death or a concomitant condition not associated with death. Myocardial involvement was categorized as either (1) coronary artery related myocardial infarction, (2) microangiopathy with interstitial edema and erythrocyte aggregates occluding the capillaries with or without lymphomononuclear infiltration and (3) lymphocyte myocarditis. The presence of myocardial involvement was assessed with regard to age, gender and autopsy-verified significant coronary artery disease (CAD) and diabetes (information available only for the clinical autopsy cohort). Results 102 autopsies were included, of whom 42 were clinical and 60 forensic (age 73±15 years, 50% men; 58% had CAD). Ten patients from the clinical autopsy cohort had diabetes (24%). Deaths were COVID-19 related in 80 patients (78%). Myocardial infarction was noted in 3 (2.9%) patients. Microangiopathy was seen in 45 (44%) and lymphocyte myocarditis in 2 (1.9%) patients, of whom it was the primary cause of death in one. The prevalence of microangiopathy did not differ between patients with and without significant DAD (46% vs 45%, p=0.848). Patients with diabetes were more likely to have microangiopathy with lymphomononuclear infiltration in the myocardium than patients without diabetes (40% vs 3.1%, p=0.008; OR=22, 95% CI 1.63–305, p=0.020 after adjustment for age, gender and CAD) Conclusion Systematically performed autopsies revealed causative association between SARS-CoV2 and death in the vast majority. Myocardial involvement was observed in nearly half of the patients and was not related to the extent of DAD. Myocarditis appears to be a rare finding, though it can be the primary cause of death. Microangiopathy with capillary occlusion and lymphomononuclear infiltration in the myocardium was associated with the history of diabetes. Funding Acknowledgement Type of funding sources: None.

Capillary bonding of membranes by viscous polymers: Infiltration kinetics and mechanical integrity of the bonded polymer/membrane structures

Capillary infiltration of porous medium impacts applications across oil recovery, soil science, and hydrology. The infiltration kinetics is typically captured by a range of models that differ in the approximation of pore structures, fluid properties, and filling ratio. Capillary bonding of a porous membrane by a polymer melt is important for membrane device manufacturing. However, both the capillary infiltration kinetics and the resulting bonding strength or mechanical integrity have not been reported. In this work, we measure the kinetics of capillary infiltration of a viscous polypropylene (PP) in polyethersulfone (PES) membranes with a normal pore size of 200 nm and varying degrees of hydrophilicity. The time-dependent infiltration depth was quantified ex situ by imaging the cross-sections of the bonded PP film/PES membranes. The microscopic details of the bonded interface were characterized by high-resolution nanomechanical imaging, while the contact angles of PP on the PES surfaces were measured by the sessile droplet method. The results show that the infiltration kinetics at 180 °C is better described by the Cai model that incorporates membrane pore structures (porosity, tortuosity, pore size), compared with the basic Lucas Washburn model intended for isolated cylindrical pores. The infiltration kinetics at 200 °C appears significantly slower than the predictions of both models, which is hypothesized to be a result of pore deformation/collapse due to the capillary pressure when the PES approaches the rubbery state. Regardless of bonding temperature, the resulting mechanical integrity of the bonded PP film/PES membrane, as quantified by a modified T-peel test, is dictated by the fracture strength of the membranes and weakly decreases with the increase of infiltration depth.

The effect of roller pressure and share of plant matter in mulching soil cultivation on its density and water content

The aim of this study was to assess the impact of the roller load (with cultivating tools) and doses of plant matter (straw and charlock) mixed with soil on the air and humidity conditions of such soil. The innovation of the research consisted in abandoning the use of Kopecky’s cylinders: the bulk density of mulched soil was determined by measuring its mass and volume, which it obtained in vases before and after the roller work. Capillary infiltration was also carried out for soil in vases.Variable research factors characterizing the roller working conditions in the mulching tillage, were: source/type of plant material cut into 10 cm chopped straw, its share in soil, three ranges of soil water content and vertical unit load on the roller.Increasing the straw dose to 30 Mg.ha−1 reduces the bulk density from 1.17 to 0.76 g.cm−3, while increasing the dose of charlock to 60 Mg.ha−1 under these conditions, it reduces the density to 1.03 g.cm−3. At the same time, humidity conditions change: volumetric water content decreases in case of straw from 13.9% to 8.5% and increases in case of charlock to 17.4%. Changes occur also in case of full water capacity.

Bone marrow-derived mesenchymal stem cells transplanted into a vascularized biodegradable tube containing decellularized allogenic nerve basal laminae promoted peripheral nerve regeneration; can it be an alternative of autologous nerve graft?

Previously, we showed silicone nerve conduits containing a vascular bundle and decellularized allogenic basal laminae (DABLs) seeded with bone marrow-derived mesenchymal stem cells (BMSCs) demonstrated successful nerve regeneration. Nerve conduits should be flexible and biodegradable for clinical use. In the current study, we used nerve conduits made of polyglycoric acid (PGA) fiber mesh, which is flexible, biodegradable and capillary-permeable. DABLs were created using chemical surfactants to remove almost all cell debris. In part 1, capillary infiltration capability of the PGA tube was examined. Capillary infiltration into regenerated neural tissue was compared between the PGA tube with blood vessels attached extratubularly (extratubularly vascularized tube) and that containing blood vessels intratubularly (intratubularly vascularized tube). No significant difference was found in capillary formation or nerve regeneration between these two tubes. In part 2, a 20 mm gap created in a rat sciatic nerve model was bridged using the extratubularly vascularized PGA tube containing the DABLs with implantation of isogenic cultured BMSCs (TubeC+ group), that containing the DABLs without implantation of the BMSCs (TubeC- group), and 20 mm-long fresh autologous nerve graft (Auto group). Nerve regeneration in these three groups was assessed electrophysiologically and histomorphometrically. At 24 weeks, there was no significant difference in any electrophysiological parameters between TubeC+ and Auto groups, although all histological parameters in Auto group were significantly greater than those in TubeC+ and TubeC- groups, and TubeC+ group demonstrated significant better nerve regeneration than TubeC- group. The transplanted DABLs showed no signs of immunological rejection and some transplanted BMSCs were differentiated into cells with Schwann cell-like phenotype, which might have promoted nerve regeneration within the conduit. This study indicated that the TubeC+ nerve conduit may become an alternative to nerve autograft.

Polymer-Infiltrated Nanoparticle Films Using Capillarity-Based Techniques: Toward Multifunctional Coatings and Membranes.

Polymer-infiltrated nanoparticle films (PINFs) are a new class of nanocomposites that offer synergistic properties and functionality derived from unusually high fractions of nanomaterials. Recently, two versatile techniques,capillary rise infiltration (CaRI) and solvent-driven infiltration of polymer (SIP), have been introduced that exploit capillary forces in films of densely packed nanoparticles. In CaRI, a highly loaded PINF is produced by thermally induced wicking of polymer melt into the nanoparticle packing pores. In SIP, exposure of a polymer-nanoparticle bilayer to solvent vapor atmosphere induces capillary condensation of solvent in the pores of nanoparticle packing, leading to infiltration of polymer into the solvent-filled pores. CaRI/SIP PINFs show superior properties compared with polymer nanocomposite films made using traditional methods, including superb mechanical properties, thermal stability, heat transfer, and optical properties. This review discusses fundamental aspects of the infiltration process and highlights potential applications in separations, structural coatings, and polymer upcycling-a process to convert polymer wastes into useful chemicals.

3D-printed biodegradable composite scaffolds with significantly enhanced mechanical properties via the combination of binder jetting and capillary rise infiltration process

For hard tissue engineering applications, biodegradable composite scaffolds have been extensively investigated because of their satisfactory mechanical properties and biocompatibility. Recently, 3D printing processes have received substantial attention in the tissue engineering field because of their ability to be customized for tissues that have suffered different types of loss or damage for each patient. However, previous studies on material extrusion-based techniques lack flexibility in the filler loading amount and cannot fulfill requirements that aim to enhance mechanical properties and biocompatibility. Herein, we propose a biodegradable polymer-based composite scaffolds with high ceramic loadings fabricated using the binder jetting (BJ) technique conjugated with capillary rise infiltration. A calcium sulfate hemihydrate (CSH) scaffold was fabricated using BJ-based 3D printing. Thereafter, CSH was transformed into biphasic calcium phosphate (BCP) using hydrothermal treatment, followed by heat treatment. Melted polycaprolactone (PCL) was infiltrated in the resulting BCP scaffold. BCP was then completely dispersed in the PCL matrix, and the calculated PCL loading in the BCP matrix exceeded 40 vol%. The PCL/BCP composite scaffold demonstrated the highest compressive strength, moduli, and toughness with the fracture mode shifted from brittle to less brittle. Moreover, a stable PCL/BCP surface promotes initial cell responses and shows sufficient proliferation and differentiation of pre-osteoblast cells.

Effect of graphite addition on wear behaviour of hybrid Cu/TiC-Gr infiltrated composites

A composite of interest for high-temperature applications, where high thermal conductivity, dimensional stability, and wear resistance are required, is the Cu/TiC-Graphite hybrid system. The wear behaviour of three different composites with a graphite volume of 1%, 3% and 5% was investigated, for a total volume of 60% of reinforcement, in a pin-on-disc arrangement with a steel sphere counterpart of 66 HRC hardness. The composites were synthesized by capillary liquid copper infiltration into porous TiC-Gr preforms, obtaining materials with acceptable matrix-to-reinforcement bonding, homogeneous distribution of the reinforcing particles and absence of second phases. The tribological characterization indicated that the coefficient of friction decreases with the volumetric fraction of graphite in the composites as it enriches the wear surface. The pure copper matrix showed a wear rate up to four times that of the composites under maximum wear conditions. In all materials, the wear rate increased with applied load and sliding velocity. A higher graphite content led to a lower rate of wear so that the adhesion wear mechanism of pure copper changed to abrasion and delamination with tribochemical products on the surfaces of the Cu/TiC and Cu/TiC-Gr composites forming a mechanically mixed layer. The wear systems with graphite additions showed partial lubrication of the contact surfaces.

Engineering of axially vascularized bone tissue using natural coral scaffold and osteogenic bone marrow mesenchymal stem cell sheets

IntroductionBlood supply remains one of the obstacles to large bone tissue engineering. This study aimed to generate vascularized bone tissue by inducing axial vascularization into a construct combining natural coral scaffold and a bone marrow mesenchymal stem cells (BMSCs) sheet. Material and methodsIsolated BMSCs were cultured to form an osteogenic cell sheet using a continuous culture method. Natural coral scaffolds were prepared into customized shape with a cylinder of 20 mm length, 8 mm in outer diameter and 5 mm in inner diameter. Then, the freed superficial inferior epigastric vessel of rabbits was first wrapped with a cell sheet, and then inserted into the central passage of the scaffold, after being wrapped with another cell sheet, the complexes were implanted subcutaneously into a rabbit groin area. In contrast, the sheet-scaffold construct that implanted into groin subcutaneous area of the other side of the same rabbit with the distal end of the blood vessel was ligated, which was considered as control. New bone and vascularization formation were evaluated at 12 weeks postoperatively. ResultsThe volume of new bone formation and amount of capillary infiltration in the vascular circulation group were significantly greater than that in the vascular ligation group, which suggested that insertion of axial vessels could significantly promote angiogenesis and osteogenesis of the tissue-engineered bone. ConclusionsThese findings indicate that inserting an arteriovenous bundle into the constructs of mesenchymal stem cell sheet and coral has great potential for clinical applications to repair large bone defects.

Polymer-infiltrated nanoplatelet films with nacre-like structure via flow coating and capillary rise infiltration (CaRI)

Alignment of highly anisotropic nanomaterials in a polymer matrix can yield nanocomposites with unique mechanical and transport properties. Conventional methods of nanocomposite film fabrication are not well-suited for manufacturing composites with very high concentrations of anisotropic nanomaterials, potentially limiting the widespread implementation of these useful structures. In this work, we present a scalable approach to fabricate polymer-infiltrated nanoplatelet films (PINFs) based on flow coating and capillary rise infiltration (CaRI) and study the processing-structure-property relationship of these PINFs. We show that films with high aspect ratio (AR) gibbsite (Al (OH)3) nanoplatelets (NPTs) aligned parallel to the substrate can be prepared using a flow coating process. NPTs are highly aligned with a Herman's order parameter of 0.96 and a high packing fraction >80 vol%. Such packings show significantly higher fracture toughness compared to low AR nanoparticle (NP) packings. By depositing NPTs on a polymer film and subsequently annealing the bilayer above the glass transition temperature of the polymer, polymer infiltrates into the tortuous NPT packings though capillarity. We observe larger enhancement in the modulus, hardness and scratch resistance of NPT films upon polymer infiltration compared to NP packings. The excellent mechanical properties of such films benefit from both thermally promoted oxide bridge formation between NPTs as well as polymer infiltration increasing the strength of NPT contacts. Our approach is widely applicable to highly anisotropic nanomaterials and allows the generation of mechanically robust polymer nanocomposite films for a diverse set of applications.

Kinetics of liquid metal infiltration in TiC-SiC or SiC porous compacts

TiSi2/SiC composites are promising materials for high temperature applications. The synthesis of these composites by metal infiltration is an interesting method that is not still mastered. This study aims at identifying the thermodynamic and kinetic processes involved during the synthesis of TiSi2/SiC composites by capillary infiltration of liquid silicon or Si-Ti molten alloys in porous compacts. Three cases were examined to produce dense TiSi2/SiC materials: 1) the infiltration of molten TiSi2 in pure SiC compacts at 1550 °C, 2) the reactive infiltration of the molten eutectic Ti0.16Si0.84 alloy in SiC + TiC compacts at 1380 °C, and 3) the reactive infiltration of pure liquid silicon in SiC + TiC compacts at 1450 °C. The effect of a TiC excess was considered for each reactive case. The infiltration kinetics and the filling percentage were measured from the monitoring of the weight gain increase. The decisive role played by thermodynamics on the infiltration progress is confirmed. It induces the dissolution and diffusion of Ti atoms from TiC which results in the presence of free silicon in the infiltrated areas. Excess content of TiC is not found favorable to the infiltration. This original study based on thermodynamic calculations and kinetic measurements at high temperatures provides decisive results for a complete understanding and improvements of the examined processes.

Heterostructured Polymer‐Infiltrated Nanoparticle Films with Cavities via Capillary Rise Infiltration

AbstractPolymer‐infiltrated nanoparticle films (PINFs) that have high volume fractions (>50 vol%) of nanoparticles (NPs) possess enhanced properties making them ideal for various applications. Capillary rise infiltration (CaRI) of polymer and solvent‐driven infiltration of polymer (SIP) into pre‐assembled NP films have emerged as versatile approaches to fabricate PINFs. Although these methods are ideal for fabricating PINFs with homogenous structure, several applications including separations, and photonic/optical coatings would benefit from a method that enables scalable manufacturing of heterostructured (i.e., films with variation in structural properties such as porosity, composition, refractive indices, etc.) PINFs. In this work, a new technique is developed for fabricating heterostructured PINFs with cavities based on CaRI. A bilayer composed of densely packed inorganic NP layer atop polymer NP layer is thermally annealed above the glass transition temperature of the polymer NP, which induces CaRI of the polymer into the interstices of the inorganic NP layer. Exploiting the difference in the sizes of the two particles, heterostructured double stack PINFs composed of a PINF and a layer with large cavities are produced at a moderate temperature (<200 °C). Using these heterostructured PINFs, Bragg reflectors that can detect the presence of wetting agents in water are fabricated.

Effects of ultrasonic treatment on the structure and rehydration peculiarity of freeze-dried soy protein isolate gel

• The structure of freeze-dried SPI gel was affected by ultrasonic treatment. • The storage modulus of freeze-dried SPI gel was affected by ultrasonic treatment. • Ultrasonic treatment affects network structures of freeze-dried SPI gel. • Ultrasonic treatment affects the rehydration peculiarity of freeze-dried SPI gel. Different levels of ultrasonic power (0, 100, 200, 300, 400, and 500 W) were applied to soybean protein isolate [SPI] solution to evaluate the effects of ultrasonic treatment (4°C) on the microstructure and rehydration peculiarity (rehydration kinetics, texture profile analysis [TPA], water-holding capacity, and water distribution) of freeze-dried SPI gel. Suitable ultrasonic treatment (4°C) reduced the average size and increased the energy storage modulus of SPI solution relative to those of untreated SPI solution. The formed gel has a uniform and dense network structure. The improved the water-holding capacity and texture, and enhanced the capillary percolation of freeze-dried SPI gel during rehydration. And enlarged the size of holes in rehydrated SPI gel and made the water release rate, relaxation time T 22 , M 22 , gel hardness of rehydrated SPI gel were significantly higher than that of fresh SPI gel ( P < 0.05). Therefore, freeze-dried SPI gel with a fine texture and high rehydration rate can be prepared when ultrasonic power of 300 W.

Polyethylene three-dimensional nano-networks: How lateral chains affect metamaterial formation

Polymers occupy a central role in current society due to their utility and versatile properties. As part of the class of soft materials, polymers have also been employed in research through nanostructuration and functionalization, looking for the development of new metamaterials with wide applicability in science and society. A particular polymer, Polyethylene, has been widely used both in research and commodities, and new ways to nanostructure and improve its functionality should be considered. Here, we report on the nanostructuration of polyethylene for the fabrication of three-dimensional nanonetworks, by resorting to 3 different variants of polyethylene: low density, high density, and ultra-high molecular weight. Through the melt infiltration of these polymers into well-known three-dimensional interconnected anodic aluminum oxide templates (3D-AAO), a study can be performed to understand the effects of the chain length, structure, and chain-branching of the used polymers on the stability and integrity of the resulting polymeric nanonetworks. This was accomplished by performing infiltrations in the presence of excess bulk material and quenching the infiltration process to access transient infiltration stages. The morphology of these networks was analyzed through SEM and STEM-HAADF to understand the differences arising from polymer structure. The observed results are interpreted through the use of the Lucas-Washburn equation for capillary flow and the determination of the critical contact angle for spontaneous capillary infiltration. The resulting metamaterials also exhibit photonic responses, resulting from the replication of the periodic nature of the employed templates.

Insights into arc-assisted self-propagating high temperature synthesis of TiB2-TiC ceramic coating via wire-arc deposition

TiB2-TiC ceramic coating was fabricated by wire-arc deposition of Ti-B4C cored wire in conjunction with self-propagating high temperature synthesis (SHS) technology, to enhance the hardness and wear resistance of Ti. Results showed that a periodic combustion reaction, triggered by the capillary infiltration of molten Ti sheath into the inside B4C particles, occurred as the wire entered the arc zone. During combustion reaction, B4C experienced the course of dissolution as well as the transformation of decarbonization expressed as B4C→B13C2→B13Cx(1.27<x<2.00). In particular, the loss of C was more notable at combustion front region. The as-synthesized coating exhibited ultralow porosity thanks to the elevated adiabatic temperature, and possessed gradient microstructures formed due to the dissolution-precipitation mechanism. Mechanical and tribological tests showed that the coating had ultrahigh microhardness (2140 HV0.5, close to theorical value) and low wear rate (5.5×10−3 mm−3 min-1·N-1). The superior performance was attributed to ultralow porosity and high-strength coherent TiB2/TiC interface.

Coordinating capillary infiltration with anodic oxidation: a multi-functional strategy for electrochemical fabrication of graphene.

Electrochemical exfoliation of graphite stands out as a promising alternative to the existing methods for scalable graphene fabrication. However, factors governing the electrochemical process and the underlying mechanism are complex and how to effectively control the exfoliation process is far from completely clear despite many attempts in previous works. Herein, for the first time, capillary infiltration, anodic oxidation and their dependence on temperature were found to be critical in determining the electrolyte infiltration and the anodic oxidation process. On this basis, we achieved tuning of sheet dimensions (both thickness and lateral size) and surface chemistry of graphene by facilely controlling the temperature (5–95 °C). Four kinds of graphene materials featuring small size, porosity, water dispersibility and large size can be selectively fabricated in the same electrolyte system at different temperatures. Especially, low-temperature exfoliation results in high yields (99.5%) of small-sized graphene, which is a new breakthrough for electrochemical methods. The finding and associated mechanism of temperature's influence on both capillary infiltration and anodic oxidation not only deepen our understanding of the electrochemical exfoliation, but also make electrochemistry a versatile technique for graphene fabrication.

Characterization of SiC ceramics with complex porosity by capillary infiltration: Part B – Filling by molten silicon at 1500 °C

In Part A of this study, infiltrations experiments of porous SiC samples by hexadecane with pore-size distributions comprising small and large pores were realized. Two successive stages were identified during the filling of these samples corresponding to the infiltration of the two types of pores. The experimental data were successfully treated with a new analytical function. In Part B, it was found that this function can also be applied to the analysis of the mass gain during molten silicon infiltration at 1500 °C. Prior to silicon infiltration, it was found that the operating temperature induces a shift of the pore size distributions towards larger values. A dissolution-recrystallisation mechanism can also occur during the infiltration of silicon. During the first stage, liquid silicon fills rapidly larger pores than hexadecane. The kinetics are significantly larger with liquid silicon. Consequently, the durations for the complete filling are very short with molten silicon.

Characterization of SiC ceramics with complex porosity by capillary infiltration: Part A - Filling by hexadecane at 20 °C

The characterization of the porosity of ceramic materials is of prime importance for numerous applications. The work is being presented in two parts: A and B. In this part (Part A), several porous SiC samples exhibiting different sizes and porosity spectra were characterized by capillary infiltration of hexadecane at room temperature. The model materials contain a bimodal pore population generated by cracks and porogens. The monitoring of the weight increase in time for each sample evidence the occurrence of two successive filling stages with specific kinetics, except for the reference samples which contain only one kind of pore. The first kinetic is found clearly larger than the second. A new analytical function was used to identify the transition times and the kinetics of each stage. The various values of the kinetics revealed the occurrence of different infiltration mechanisms. The same model correlates silicon infiltration observations as well (Part B).