Analysis of the foam-forming of non-woven lightweight fibrous materials using X-ray tomography

Burke, Steven R.; Möbius, Matthias E.; Hjelt, Tuomo; Ketoja, Jukka A.; Hutzler, Stefan

doi:10.1007/s42452-021-04172-9

Cited by 14 publications

(23 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Liquid foams are excellent model systems for complex cellular structures, and foams including elastic membranes as the one we describe here could have potential relevance for tissue growth [28]. Interactions between foams and flexible slender structures also occur in widely used fabrication techniques such as foam-forming of cellulose for the paper industry [29,30]. Finally, using a UV-curable system, we have proposed a way to mold materials with characteristic shapes and curves resulting from the elasto-capillary competition.…”

Section: Discussionmentioning

confidence: 97%

Elastocapillary deformation of thin elastic ribbons in 2D foam columns

Jouanlanne¹,

Egelé²,

Favier³

et al. 2021

Preprint

View full text Add to dashboard Cite

The ability of liquid interfaces to shape slender elastic structures provides powerful strategies to control the architecture of mechanical self assemblies. However, elastocapillarity-driven intelligent design remains unexplored in more complex architected liquids -such as foams. Here we propose a model system which combines an assembly of bubbles and a slender elastic structure. Arrangement of soap bubbles in confined environments form well-defined periodic structures, dictated by Plateau's laws. We consider a 2D foam column formed in a square section cylinder in which we introduce an elastomer ribbon, leading to architected structures whose geometry is guided by a competition between elasticity and capillarity. In this system, we quantify both experimentally and theoretically the equilibrium shapes, using X-ray micro-tomography and energy minimisation techniques. Beyond the understanding of the amplitude of the wavy elastic ribbon deformation, we provide a detailed analysis of the profile of the ribbon, and show that such setup can be used to grant a shape to a UV-curable composite slender structure, as a foam-forming technique suitable to miniaturisation. In more general terms, this work provides a stepping stone towards an improved understanding of the interactions between liquid foams and slender structures.

show abstract

Section: Discussionmentioning

confidence: 97%

Elastocapillary deformation of thin elastic ribbons in 2D foam columns

Jouanlanne¹,

Egelé²,

Favier³

et al. 2021

Preprint

View full text Add to dashboard Cite

show abstract

“…Foam-formed fiber networks have a unique microporous structure with planar structural variation originating from bubbles, [77,130] as discussed earlier in Sections 5.2 and 5.3. Moreover, X-ray microtomography has shown that fiber networks tend to form separate layers in the thickness direction at very low average material density.…”

Section: Fiber Network Structurementioning

confidence: 95%

“…Despite this rather drastic change in the fiber foam structure, traces of bubble structure still remain visible in the final dried sheet. [21,77,129,130] Al-Qararah [22] showed that lower density can be achieved in a sheet sample by using foam as the carrier phase instead of water with equal surfactant concentration. Thus, the bubble structure is essential in setting the densitynot only the reduced bonding because of surfactant.…”

Section: Materials Densitymentioning

confidence: 99%

“…Moreover, X-ray microtomography has shown that fiber networks tend to form separate layers in the thickness direction at very low average material density. [130] Therefore, the structure can deviate a lot from a simple random fiber network, and one has to be cautious when using averaging formulas such as Equation (15).…”

Section: Fiber Network Structurementioning

confidence: 99%

“…The associated water flow can turn fibers toward the vertical direction in the dried material. [130] This mechanism may be important, especially when increasing the foam volume, so that the upper network layers are formed by flow that enters the forming section later than the bottom flow. The delayed application of vacuum for Figure 29.…”

Section: Fiber Network Structurementioning

confidence: 99%

See 2 more Smart Citations

Foam forming of fiber products: a review

Hjelt

Ketoja

Kiiskinen

et al. 2021

Journal of Dispersion Science and Technology

View full text Add to dashboard Cite

Aqueous foam can be used as a transfer medium to form lightweight materials from natural and man-made fibers together with other types of raw materials. This review discusses mechanisms that underlie the forming process and thus influence physical properties of formed fiber networks such as microporous structure, strength behavior, and transport properties. Homogeneous fiber materials can be formed from versatile raw materials, which makes the technology suitable for a vast range of product applications. An intriguing feature of the method is that the wet foam characteristics provide an additional tool to tailor the performance of the dried material. Understanding foam rheology and how that is affected by added fibers is important in developing the forming process. We introduce both fundamental foam properties and practical forming methods, and show how the material properties are affected by the foam-fiber interaction. The basic features of an industrial production process are also described. The potential material properties are compared against key requirements in typical product applications.

show abstract

Energy absorption and resilience in quasi-static loading of foam-formed cellulose fibre materials

Pääkkönen,

Ketoja,

Paltakari

2024

Cellulose

View full text Add to dashboard Cite

To avoid microplastic pollution, there is an urgent need to replace fossil-based cushioning materials in packaging with easily recyclable alternatives. Here, we investigated the potential of lightweight cellulose fibre materials as a solution for mechanical protection. The quasi-static compression was studied among a vast set of 129 different foam-formed trial points with material density ranging from 21 kg/m3 to 123 kg/m3. The trial points included two different fibre types, bleached softwood kraft pulp (BSKP) and bleached chemithermomechanical pulp (CTMP), with varied refining level, pulp consistency, foaming conditions, surfactant type, strength additives, and final material density and thickness. Besides a correlation analysis of factors affecting compression stress and resilience, the results were reflected against a new theoretical prediction of energy absorption for an ideal low-density random fibre network. The theory predicts the initially-high cushion factor to rapidly drop down to the level of 4‒5 at 40‒80% compression. A similar behaviour was seen among the actual samples, despite their various non-ideal features. At 50% compression, the average cushion factor across the whole data set was 4.84 ± 0.10, being close to the theoretical prediction of 4.61 for the ideal case. The smallest cushion factor of 3.6 was found for a CTMP sample. The recovery from compression varied slightly among the samples and appeared highest for the material density of 60‒100 kg/m3, following the predicted proportion of non-buckled fibre segments. According to the results, cellulose fibre-based cushions have a soft initial response, which is preferable for fragile items. Graphical abstract

show abstract

Analysis of the foam-forming of non-woven lightweight fibrous materials using X-ray tomography

Cited by 14 publications

References 18 publications

Elastocapillary deformation of thin elastic ribbons in 2D foam columns

Elastocapillary deformation of thin elastic ribbons in 2D foam columns

Foam forming of fiber products: a review

Energy absorption and resilience in quasi-static loading of foam-formed cellulose fibre materials

Contact Info

Product

Resources

About