Research

16 pages, 4817 KiB

Open AccessArticle

Microstructural and Thermo-Physical Characterization of a Water Hyacinth Petiole for Thermal Insulation Particle Board Manufacture

by Adela Salas-Ruiz, María del Mar Barbero-Barrera and Trinidad Ruiz-Téllez

Materials 2019, 12(4), 560; https://doi.org/10.3390/ma12040560 - 13 Feb 2019

Cited by 24 | Viewed by 8644

Abstract

Water Hyacinth (Eichhornia crassipes) is a dangerous and invasive aquatic species, of which global concern has sharply risen due to its rapid growth. Despite ample research on its possible applications in the construction field, there are no clear references on the [...] Read more.

Water Hyacinth (Eichhornia crassipes) is a dangerous and invasive aquatic species, of which global concern has sharply risen due to its rapid growth. Despite ample research on its possible applications in the construction field, there are no clear references on the optimal use of the plant in finding the most efficient-use building material. In this paper, a microstructural and chemical characterization of the Water Hyacinth petiole was performed, in order to find the most efficient use as a construction material. Subsequently, two types of binder-less insulation panels were developed, with two types of particle size (pulp and staple). A physical, mechanical, and thermal characterization of the boards was performed. These results demonstrated that it is possible to manufacture self-supporting Water Hyacinth petiole panels without an artificial polymer matrix for thermal insulation. The boards showed good thermal conductivity values, ranging from 0.047–0.065 W/mK. In addition, clear differences were found in the properties of the boards, depending on the type of Water Hyacinth petiole particle size, due to the differences in the microstructure. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Graphical abstract

16 pages, 3242 KiB

Open AccessArticle

Rate-Type Age-Dependent Constitutive Formulation of Concrete Loaded at an Early Age

by Seung-Gyu Kim, Yeong-Seong Park and Yong-Hak Lee

Materials 2019, 12(3), 514; https://doi.org/10.3390/ma12030514 - 08 Feb 2019

Cited by 6 | Viewed by 2622

Abstract

A general formulation framework for an age-dependent constitutive equation of concrete is presented to account for the development of the elastic modulus at an early age. This is achieved by expanding the total stress vs. strain relation with respect to the time-varying elastic [...] Read more.

A general formulation framework for an age-dependent constitutive equation of concrete is presented to account for the development of the elastic modulus at an early age. This is achieved by expanding the total stress vs. strain relation with respect to the time-varying elastic modulus. Two types of constitutive formulation frameworks are derived depending on whether (or not) the time-varying effect of the elastic modulus was taken into account in the linearized series expansion. The causes for the age-dependent deformations under sustained loads are defined in the formulation based on the two internal mechanisms of delayed elasticity and the ageing phenomenon. The ageing phenomenon is incorporated in a conventional delayed strain concept in terms of the variable elastic modulus with time. Four cases of age-dependent constitutive equations are formulated within the presented formulation framework by employing different types of creep models. The mechanical characteristics of the terms that comprise the various constitutive equations are examined and compared. Numerical application of the time-dependent test results of cylindrical specimens indicate that the creep formulation that considered the elastic modulus development showed a good agreement with the experimental result while the formulation that did not consider the elastic modulus development underestimated the result by 15%. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

21 pages, 31535 KiB

Open AccessArticle

Compression Strength Mechanisms of Low-Density Fibrous Materials

by Jukka A. Ketoja, Sara Paunonen, Petri Jetsu and Elina Pääkkönen

Materials 2019, 12(3), 384; https://doi.org/10.3390/ma12030384 - 26 Jan 2019

Cited by 21 | Viewed by 5539

Abstract

In this work we challenge some earlier theoretical ideas on the strength of lightweight fiber materials by analyzing an extensive set of foam-formed fiber networks. The experimental samples included various different material densities and different types of natural and regenerated cellulose fibers. Characterization [...] Read more.

In this work we challenge some earlier theoretical ideas on the strength of lightweight fiber materials by analyzing an extensive set of foam-formed fiber networks. The experimental samples included various different material densities and different types of natural and regenerated cellulose fibers. Characterization of the samples was performed by macroscopic mechanical testing, supported by simultaneous high-speed imaging of local deformations inside a fiber network. The imaging showed extremely heterogeneous deformation behavior inside a sample, with both rapidly proceeding deformation fronts and comparatively still regions. Moreover, image correlation analysis revealed frequent local fiber dislocations throughout the compression cycle, not only for low or moderate compressive strains. A new buckling theory including a statistical distribution of free-span lengths is proposed and tested against the experimental data. The theory predicts universal ratios between stresses at different compression levels for low-density random fiber networks. The mean ratio of stresses at 50% and 10% compression levels measured over 57 different trial points, 5.42 ± 0.43, agrees very well with the theoretical value of 5.374. Moreover, the model predicts well the effect of material density, and can be used in developing the properties of lightweight materials in novel applications. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Graphical abstract

14 pages, 7436 KiB

Open AccessArticle

Measuring the Cohesive Law in Mode I Loading of Eucalyptus globulus

by Almudena Majano-Majano, Antonio José Lara-Bocanegra, José Xavier and José Morais

Materials 2019, 12(1), 23; https://doi.org/10.3390/ma12010023 - 21 Dec 2018

Cited by 17 | Viewed by 3185

Abstract

Assessing wood fracture behavior is essential in the design of structural timber elements and connections. This is particularly the case for connections with the possibility of brittle splitting failure. The numerical cohesive zone models that are used to simulate the fracture behavior of [...] Read more.

Assessing wood fracture behavior is essential in the design of structural timber elements and connections. This is particularly the case for connections with the possibility of brittle splitting failure. The numerical cohesive zone models that are used to simulate the fracture behavior of wood make it necessary to assume a cohesive law of the material that relates cohesive tractions and crack opening displacements ahead of the crack tip. This work addresses the determination of the fracture cohesive laws of Eucalyptus globulus, a hardwood species with great potential in timber engineering. This study centres on Mode I fracture loading for RL and TL crack propagation systems using Double Cantilever Beam tests. The Compliance-Based Beam Method is applied as the data reduction scheme in order to obtain the strain energy release rate from the load-displacement curves. The cohesive laws are determined by differentiating the relationship between strain energy release rate and crack tip opening displacement. The latter is measured by the digital image correlation technique. High strain energy release rates were obtained for this species, with no big differences between crack propagation systems. The difference between the crack systems is somewhat more pronounced in terms of maximum stress that determines the respective cohesive laws. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

15 pages, 3141 KiB

Open AccessArticle

Effect of Different Additives in Diets on Secondary Structure, Thermal and Mechanical Properties of Silkworm Silk

by Lan Cheng, Huiming Huang, Jingyou Zeng, Zulan Liu, Xiaoling Tong, Zhi Li, Hongping Zhao and Fangyin Dai

Materials 2019, 12(1), 14; https://doi.org/10.3390/ma12010014 - 20 Dec 2018

Cited by 21 | Viewed by 5276

Abstract

In this study, eight types of materials including nanoparticles (Cu and CaCO₃), metallic ions (Ca²⁺ and Cu²⁺), and amino acid substances (serine, tyrosine, sericin amino acid, and fibroin amino acid) were used as additives in silkworm diets to [...] Read more.

In this study, eight types of materials including nanoparticles (Cu and CaCO₃), metallic ions (Ca²⁺ and Cu²⁺), and amino acid substances (serine, tyrosine, sericin amino acid, and fibroin amino acid) were used as additives in silkworm diets to obtain in-situ modified silk fiber composites. The results indicate that tyrosine and fibroin amino acids significantly increase potassium content in silk fibers and induce the transformation of α-helices and random coils to β-sheet structures, resulting in higher crystallinities and better mechanical properties. However, the other additives-modified silk fibers show a decrease in β-sheet contents and a slight increase or even decrease in tensile strengths. This finding provides a green and effective approach to produce mechanically enhanced silk fibers with high crystallinity on a large scale. Moreover, the modification mechanisms of these additives were discussed in this study, which could offer new insights into the design and regulation of modified fibers or composites with desirable properties and functions. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Graphical abstract

16 pages, 14175 KiB

Open AccessArticle

Characterization and Structural Performance in Bending of CLT Panels Made from Small-Diameter Logs of Loblolly/Slash Pine

by Vanesa Baño, Daniel Godoy, Diego Figueredo and Abel Vega

Materials 2018, 11(12), 2436; https://doi.org/10.3390/ma11122436 - 30 Nov 2018

Cited by 17 | Viewed by 5358

Abstract

The main objective of this work was to study the structural viability of using small-diameter logs of Uruguayan Loblolly/Slash pine, mainly from thinning operations, to design cross-laminated timber (CLT) panels. A visual grade named “CTH” (coniferous thinning) was proposed, and 45 specimens of [...] Read more.

The main objective of this work was to study the structural viability of using small-diameter logs of Uruguayan Loblolly/Slash pine, mainly from thinning operations, to design cross-laminated timber (CLT) panels. A visual grade named “CTH” (coniferous thinning) was proposed, and 45 specimens of sawn timber boards were tested, resulting in 51% lower bending strength than that of the minimum strength class C14. Subsequently, 20 CLT panels were manufactured and experimentally tested, the results showed that the bending strength of the CLT panels was 43% above that of the individual layers. Additionally, the structural performance of the CLT panels for use in floors was calculated, and the thickness-span relationship depending on strength class and imposed load are presented. Results showed than the use of CTH timber to design CLT floors implies a volume (m³/m²) 17% higher than that using C24 timber. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

13 pages, 4003 KiB

Open AccessArticle

Injection Molding of Thermoplastic Cellulose Esters and Their Compatibility with Poly(Lactic Acid) and Polyethylene

by Pia Willberg-Keyriläinen, Hannes Orelma and Jarmo Ropponen

Materials 2018, 11(12), 2358; https://doi.org/10.3390/ma11122358 - 23 Nov 2018

Cited by 23 | Viewed by 5818

Abstract

Interest in biobased polymers from renewable resources has grown in recent years due to environmental concerns, but they still have a minimal fraction of the total global market. In this study, the injection molding of thermoplastic cellulose octanate (cellulose C8) and cellulose palmitate [...] Read more.

Interest in biobased polymers from renewable resources has grown in recent years due to environmental concerns, but they still have a minimal fraction of the total global market. In this study, the injection molding of thermoplastic cellulose octanate (cellulose C8) and cellulose palmitate (cellulose C16) were studied. The mechanical properties of injection-molded test specimens were analyzed by using tensile testing, and the internal structure of injection-molded objects was studied by using a field emission scanning electron microscopy (FE-SEM). We showed that thermoplastic cellulose C8 and cellulose C16 were completely processable without the addition of a plasticizer, which is very unusual in the case of cellulose esters. The compatibility of cellulose esters with poly(lactic acid) (PLA) and biopolyethylene (bio-PE) was also tested. By compounding the cellulose esters with PLA, the elongation of PLA-based blends could be improved and the density could be reduced. The tested thermoplastic cellulose materials were fully biobased, and have good future potential to be used in injection molding applications. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

22 pages, 6728 KiB

Open AccessArticle

Deformation and Failure Behavior of Wooden Sandwich Composites with Taiji Honeycomb Core under a Three-Point Bending Test

by Jingxin Hao, Xinfeng Wu, Gloria Oporto, Jingxin Wang, Gregory Dahle and Nan Nan

Materials 2018, 11(11), 2325; https://doi.org/10.3390/ma11112325 - 19 Nov 2018

Cited by 13 | Viewed by 4737

Abstract

A new type of Taiji honeycomb structure bonded outside with wood-based laminates was characterized from a mechanical standpoint. Both theoretical and experimental methods were employed to analyze comprehensively the deformation behavior and failure mechanism under a three-point bending test. The analytical analysis reveals [...] Read more.

A new type of Taiji honeycomb structure bonded outside with wood-based laminates was characterized from a mechanical standpoint. Both theoretical and experimental methods were employed to analyze comprehensively the deformation behavior and failure mechanism under a three-point bending test. The analytical analysis reveals that a Taiji honeycomb has 3.5 times higher strength in compression and 3.44 times higher strength in shear compared with a traditional hexagonal honeycomb. Considering the strength-weight issue, the novel structure also displays an increase in compression strength of 1.75 times and shear strength of 1.72 times. Under a three-point bending test, indentation and core shear failure played the dominant role for the total failure of a wooden sandwich with Taiji honeycomb core. Typical face yield was not observed due to limited thickness-span ratio of specimens. Large spans weaken the loading level due to the contribution of global bending stress in the compressive skin to indentation failure. A set of analytical equations between mechanical properties and key structure parameters were developed to accurately predict the threshold stresses corresponding to the onset of those deformation events, which offer critical new knowledge for the rational structure design of wooden sandwich composites. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

16 pages, 484 KiB

Open AccessArticle

Visibility Graph Feature Model of Vibration Signals: A Novel Bearing Fault Diagnosis Approach

by Zhe Zhang, Yong Qin, Limin Jia and Xin’an Chen

Materials 2018, 11(11), 2262; https://doi.org/10.3390/ma11112262 - 13 Nov 2018

Cited by 13 | Viewed by 3076

Abstract

Reliable fault diagnosis of rolling bearings is an important issue for the normal operation of many rotating machines. Information about the structure dynamics is always hidden in the vibration response of the bearings, and it is often very difficult to extract them correctly [...] Read more.

Reliable fault diagnosis of rolling bearings is an important issue for the normal operation of many rotating machines. Information about the structure dynamics is always hidden in the vibration response of the bearings, and it is often very difficult to extract them correctly due to the nonlinear/chaotic nature of the vibration signal. This paper proposes a new feature extraction model of vibration signals for bearing fault diagnosis by employing a recently-developed concept in graph theory, the visibility graph (VG). The VG approach is used to convert the vibration signals into a binary matrix. We extract 15 VG features from the binary matrix by using the network analysis and image processing methods. The three global VG features are proposed based on the complex network theory to describe the global characteristics of the binary matrix. The 12 local VG features are proposed based on the texture analysis method of images, Gaussian Markov random fields, to describe the local characteristics of the binary matrix. The feature selection algorithm is applied to select the VG feature subsets with the best performance. Experimental results are shown for the Case Western Reserve University Bearing Data. The efficiency of the visibility graph feature model is verified by the higher diagnosis accuracy compared to the statistical and wavelet package feature model. The VG features can be used to recognize the fault of rolling bearings under variable working conditions. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

23 pages, 11725 KiB

Open AccessArticle

Experimental Study of Rubberized Concrete Stress-Strain Behavior for Improving Constitutive Models

by Kristina Strukar, Tanja Kalman Šipoš, Tihomir Dokšanović and Hugo Rodrigues

Materials 2018, 11(11), 2245; https://doi.org/10.3390/ma11112245 - 11 Nov 2018

Cited by 39 | Viewed by 7861

Abstract

Inclusion of rubber into concrete changes its behavior and the established shape of its stress-strain curve. Existing constitutive stress-strain models for concrete are not valid in case of rubberized concrete, and currently available modified models require additional validation on a larger database of [...] Read more.

Inclusion of rubber into concrete changes its behavior and the established shape of its stress-strain curve. Existing constitutive stress-strain models for concrete are not valid in case of rubberized concrete, and currently available modified models require additional validation on a larger database of experimental results, with a wider set of influential parameters. By executing uniaxial compressive tests on concrete with rubber substituting 10%, 20%, 30%, and 40% of aggregate, it was possible to study and evaluate the influence of rubber content on its mechanical behavior. The stress-strain curve was investigated in its entirety, including compressive strength, elastic modulus, strains at significant levels of stress, and failure patterns. Experimental results indicated that increase of rubber content linearly decreases compressive strength and elastic modulus, but increases ductility. By comparing experimental stress-strain curves with those plotted using available constitutive stress-strain models it was concluded that they are inadequate for rubberized concrete with high rubber content. Based on determined deviations an improvement of an existing model was proposed, which provides better agreement with experimental curves. Obtained research results enabled important insights into correlations between rubber content and changes of the stress-strain curve required when utilizing nonlinear material properties. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

17 pages, 2169 KiB

Open AccessArticle

Structure/Function Analysis of Nonwoven Cotton Topsheet Fabrics: Multi-Fiber Blending Effects on Fluid Handling and Fabric Handle Mechanics

by Michael Easson, Judson Vincent Edwards, Ningtao Mao, Chris Carr, David Marshall, Jianguo Qu, Elena Graves, Michael Reynolds, Andres Villalpando and Brian Condon

Materials 2018, 11(11), 2077; https://doi.org/10.3390/ma11112077 - 24 Oct 2018

Cited by 6 | Viewed by 4512

Abstract

Greige cotton (GC) has attracted interest in recent years as an eco-friendly, functional fiber for use in nonwoven topsheet materials. GC imparts favorable fluid management and sensorial properties associated with urinary liquid transport and indices related to comfort in wearable incontinence nonwovens. Nonwoven [...] Read more.

Greige cotton (GC) has attracted interest in recent years as an eco-friendly, functional fiber for use in nonwoven topsheet materials. GC imparts favorable fluid management and sensorial properties associated with urinary liquid transport and indices related to comfort in wearable incontinence nonwovens. Nonwoven GC has material surface polarity, an ambient moisture content, and a lipid/polysaccharide matrix that imparts positive fluid mechanic properties applicable to incontinence management topsheet materials. However, a better understanding of the connection between functionality and compositional aspects of molecular, mechanical, and material property relations is still required to employ structure/function relations beyond a priori design. Thus, this study focuses on the relation of key indices of material fluid and sensorial functions to nonwoven topsheet composition. Greige cotton, polypropylene, bleached cotton, and polyester fiber blends were hydroentangled at 60, 80, and 100 bar. Greige cotton polypropylene and bleached cotton were blended at ratios to balance surface polarity, whereas low percentages of polyester were added to confer whiteness properties. Electrokinetic and contact angle measurements were obtained for the hydroentangled nonwovens to assess surface polarity in light of material composition. Notably, materials demonstrated a relation of hydrophobicity to swelling as determined electrokinetically by Δζ, ζ_plateau, and contact angles greater than 90°. Subsequently, three blended nonwoven fabrics were selected to assess effects on fluid management properties including topsheet performance indices of rewet, strikethrough, and fluid handling (rate and efficiency of transport to the absorbent core). These materials aligned well with commercial topsheet fluid mechanics. Using the Leeds University Fabric Handle Evaluation System (LUFHES), the nonwovens were tested for total fabric hand. The results of the LUFHES measurements are discussed in light of fiber contributions. Fiber ratios were found to correlate well with improvement in softness, flexibility, and formability. This study provides insights that improves the understanding of the multifunctional properties accessible with greige cotton toward decisions valuable to selecting greige cotton as an environmentally friendly fiber for nonwoven topsheets. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

15 pages, 7874 KiB

Open AccessArticle

Constitutive Model Prediction and Flow Behavior Considering Strain Response in the Thermal Processing for the TA15 Titanium Alloy

by Jiang Li, Fuguo Li and Jun Cai

Materials 2018, 11(10), 1985; https://doi.org/10.3390/ma11101985 - 15 Oct 2018

Cited by 13 | Viewed by 2479

Abstract

To investigate the flow stress, microstructure, and usability of TA15 titanium alloy, isothermal compression was tested at 1073–1223 K and strain rates of 10, 1, 0.1, 0.01, and 0.001 s⁻¹, and strain of 0.9. The impact of strain and temperature on [...] Read more.

To investigate the flow stress, microstructure, and usability of TA15 titanium alloy, isothermal compression was tested at 1073–1223 K and strain rates of 10, 1, 0.1, 0.01, and 0.001 s⁻¹, and strain of 0.9. The impact of strain and temperature on thermal deformation was investigated through the exponent-type Zener–Hollomon equation. Based on the influence of various material constants (including α, n, Q, and lnA) on the TA15 titanium alloy, the strain effect was included in the constitutive equation considering strain compensation, which is presented in this paper. The validity of the proposed constitutive equation was verified through the correlation coefficient (R) and the average absolute relative error (AARE), the values of which were 0.9929% and 6.85%, respectively. Research results demonstrated that the strain-based constitutive equation realizes consistency between the calculated flow stress and the measured stress of TA15 titanium alloy at high temperatures. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

13 pages, 2312 KiB

Open AccessArticle

Effects of Ball Milling Processes on the Microstructure and Rheological Properties of Microcrystalline Cellulose as a Sustainable Polymer Additive

by Yu Zheng, Zongqiang Fu, Dong Li and Min Wu

Materials 2018, 11(7), 1057; https://doi.org/10.3390/ma11071057 - 22 Jun 2018

Cited by 55 | Viewed by 5135

Abstract

To investigate the effect of ball mill treatment of microcrystalline cellulose (MCC) on the rheological properties of MCC-polymer suspension, the structure and physicochemical characteristics of ground samples with different milling time and the rheological behaviors of MCC-starch suspensions were determined and comprehensively analyzed. [...] Read more.

To investigate the effect of ball mill treatment of microcrystalline cellulose (MCC) on the rheological properties of MCC-polymer suspension, the structure and physicochemical characteristics of ground samples with different milling time and the rheological behaviors of MCC-starch suspensions were determined and comprehensively analyzed. During the ball milling process, MCC underwent a morphological transformation from rod-like to spherical shape under the combined effect of breakage and an agglomeration regime. The particle size and crystallinity index of MCC exhibited an exponential declining trend with ball milling time. All of the milled MCC samples presented a crystalline cellulose I_β structure whereas the MCC mechanically treated in a shorter time had better thermal stability. Rheological measurements of starch/MCC suspensions indicated that all the blended paste exhibited shear thinning behavior and ‘weak’ elastic gel-like viscoelastic properties over the whole investigated range owing to the formation of entangled network structure. The rheological behavior of starch/MCC pastes was strongly dependent on milling time and concentration of MCC samples. The increase in milling time of MCC samples resulted in the loss of rheological properties of starch/MCC pastes, where the size of the MCC playing a dominant role in affecting the properties of composite suspension. In addition, a possible network within starch/MCC suspensions was proposed. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Figure 1

16 pages, 26793 KiB

Open AccessArticle

Properties of Two-Variety Natural Luffa Sponge Columns as Potential Mattress Filling Materials

by Yuxia Chen, Kaiting Zhang, Fangcheng Yuan, Tingting Zhang, Beibei Weng, Shanshan Wu, Aiyue Huang, Na Su and Yong Guo

Materials 2018, 11(4), 541; https://doi.org/10.3390/ma11040541 - 31 Mar 2018

Cited by 12 | Viewed by 5316

Abstract

Luffa sponge (LS) is a resourceful material with fibro-vascular reticulated structure and extremely high porosity, which make it a potential candidate for manufacturing light mattress. In this study, two types of LS columns, namely high-density (HD) and low-density (LD) columns, were investigated as [...] Read more.

Luffa sponge (LS) is a resourceful material with fibro-vascular reticulated structure and extremely high porosity, which make it a potential candidate for manufacturing light mattress. In this study, two types of LS columns, namely high-density (HD) and low-density (LD) columns, were investigated as materials for filling the mattress. The results showed that the compressive strength of HD LS columns was significantly greater than that of LD LS columns. However, the densification strains of the two types of LS column were both in the range of 0.6 to 0.7. Besides, HD LS columns separately pressed to the smooth plateau region and the initial densification region exhibited a partial recovery of instant height when they were unloaded, and then both of them showed no more than 4.2% of height recovery after being allowed to rest at a constant temperature and humidity for 24 h. In contrast, when LD LS columns were compressed to the smooth plateau region, the height recovery was less than 1.62% compared to when they were pressed to the initial densification region, and that was more than 15.62%. Similar to other plant fibers used as mattress fillers, the two types of LS columns also showed good water absorption capacity—both of them could absorb water from as much as 2.07 to 3.45 times their own weight. At the same time, the two types of LS columns also showed good water desorption. The water desorption ratio of HD and LD LS columns separately reached 76.86 and 91.44%, respectively, after being let rest at a constant temperature and humidity for 13 h. Full article

(This article belongs to the Special Issue Mechanical Characterization of Bio-Based Materials and Structures)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Mechanical Characterization of Bio-Based Materials and Structures

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (14 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI