study on the swelling characteristics of bamboo based … · study on the swelling characteristics...

STUDY ON THE SWELLING CHARACTERISTICS OF BAMBOO BASEDON ITS GRADED HIERARCHICAL STRUCTURE

Jiawei ZhuDoctoral Student

E-mail: [email protected]

Hankun WangAssociate Research FellowDepartment of Biomaterials

International Center for Bamboo and RattanBeijing 100102, People’s Republic of China

andSFA and Beijing Co-built Key Laboratory of Bamboo and Rattan Science & Technology

State Forestry AdministrationBeijing 100102, People’s Republic of China

E-mail: [email protected]

Chuangui Wang*Professor

School of Forestry & Landscape ArchitectureAnhui Agricultural University

Hefei 230036, People’s Republic of ChinaE-mail: [email protected]

(Received May 2019)

Abstract. To understand the swelling characteristics of bamboo under its gradient structure, different partsof bamboo specimens have been soaked in solutions of different electrolytes. The results showed that theswelling extent of bamboo in solution is mainly influenced by chemical activity and molecular dimension ofthe solute. The dimensional increase in bamboo after swelling is mainly observed in the tangential and radialdirection, and the largest dimensional increase as a result of swelling occurred in intermediary bamboo.High-concentration strong electrolytes will cause a certain degree of recrystallization in the bamboospecimen, especially in intermediary bamboo, resulting in an increase in its mass. In summary, the con-clusion is that the removal of wax and tabaxir before swelling and the avoidance of using strong electrolytesas swelling solutions tend to improve the efficiency of swelling bamboo.

Keywords: Phyllostachys pubescens swelling characteristics, maximum percentage swelling, mass loss,hierarchical structures.

INTRODUCTION

The phenomenon of swelling is characteristic ofall elastic materials but differs somewhat fordifferent types of materials (Mantanis et al 1994a,1994b). Wood swelling in liquid has been studiedfor the past 70 yr. West (1988) assumed thatwood swelling was a bimolecular reaction merelyrequiring the collision of liquid molecules withwood. A number of scientists have made attempts

to determine the factors that influence woodswelling in liquid. Actually, wood swelling is acomplex process, and its influencing factors in-clude wood substrate and solvents, none of whichcan be used to extrapolate conclusions in-dividually. As for solvents, there are three mainfactors that influence wood swelling (Mantaniset al 1994b). The first is the dimensions of themolecule. The molecule size is in inverse pro-portion to the rate of swelling, and any increase inthe molecular size of the swelling liquid willresult in a consequent decrease in the degree of* Corresponding author

Wood and Fiber Science, 51(3), 2019, pp. 1-11https://doi.org/10.22382/wfs-2019-xxx© 2019 by the Society of Wood Science and Technology

mailto:[email protected]



https://doi.org/10.22382/wfs-2019-xxx

the swelling (Nakatani et al 2010). In addition, themolecular shape and branching and steric hin-drance also affect the swelling effect. The secondfactor is the hydrogen bond. According toIshimaru et al (2001), a correlation existed be-tween the degree of swelling and the extent ofhydrogen bonding between the constituents ofwood and those of the swelling agent. Mantaniset al (1994b) found a strange phenomenon in thestudy of the effect of the molecular size on thedegree of wood swelling. Benzyl alcohol, despitehaving a rather large molecular size, has strongswelling ability for hardwood, which might beaccounted for by its high hydrogen bonding ca-pability. The third factor is basicity. Mantaniset al (1994b) placed several specimens of NorthAmerican wood species in sealed weighingbottles with 40 different organic liquids toevaluate the influence of a wide variety of solventfactors. He found that the maximum tangentialswelling for all the wood species was linearlycorrelated with the solvent basicity. As for woodsubstrates, density and extractives are two mainfactors that influence swelling. Wood density hasbeen found to be an important factor that sig-nificantly influences the swelling of wood(Mantanis et al 1994a). In general, the hardwoodssuch as maple (Acer saccharum) swelled to amuch greater extent compared with the softwoodssuch as Douglas fir (Pseudotsuga menziesii). Thisis likely due to the greater density of hardwoods(Mantanis et al 1994a). Wood extractives aresubstances that can be extracted with organicliquids, such as resin acids, fats, terpenes, lignans,flavonoids, tannins, stilbenes, etc., or hot water(Jankowska et al 2016). A number of scientistshave made attempts to determine the reason whythe removal of extractives greatly increased thedegree of the wood swelling. Mantanis andPapadopoulos (2010) suggested that cell walldisruption could be the main reason behind thephenomenon: the extraction process expands thesize of the microscopic capillaries and acceleratesthe diffusion of the swelling liquid into the cellwall structure of wood. In addition, Mantanis et al(1995a) found that the rate of wood swelling inorganic liquids demonstrated a strong de-pendence on temperature (20-100°C). More

specifically, the correlation between temperatureand wood swelling suggests that the phenomenonof wood swelling is similar to a chemical reaction.This may be linked to minor changes in the cellwall structure when wood is treated with high-temperature liquids (Xing et al 2016; Tanaka et al2017). Based on this, Mantanis et al (1994a) firstproposed the concept of activation energies,which represents the energy required to break thewood’s hydrogen bonds to allow for woodswelling in water. The removal of extractives ora drop in temperature can increase activationenergies.

Bamboo is a tree-like giant grass composed ofhollow culms and separated by nodes along itsheight (Sharma et al 2015). It is a unique bio-composite like wood, but with vascular bundlesas the reinforcement and parenchyma cells as thematrix (Zhang et al 2017). The nonuniformdistribution of vascular bundles embedded in thematrix makes it a functionally graded material(Silva et al 2006; Li et al 2018) (similar to thevariations between wood growth rings in theradial direction). This means that the fiber dis-tribution on the cross-section of bamboo is not asuniform as that of wood. Moreover, the fibroussheath of bamboo is also changing along theradial direction. Based on this, bamboo can bedivided into three parts from the outside to theinside, namely, the outer part, the intermediarypart and, the inner part (Zhang et al 2014).Mantanis et al (1994b) suggested that cellulose isthe primary wood polymer responsible for themost part of wood swelling in his research on theinfluence of basicity (donor number), molecularvolume, and hydrogen bonding on the swellingof wood. Presumably, the swelling of bambooshould have characteristics different fromthose of wood because of its uniquely gradedstructures. Surprisingly, detailed data on theswelling of bamboo have not yet been collectedextensively. Further development in the newsolvent pulping processes requires more de-tailed information on the effects of chemicalreagents on bamboo, which has great signifi-cance in commercial exploitation and morepioneering experiments.

WOOD AND FIBER SCIENCE, JULY 2019, V. 51(3)2

In an attempt to narrow this gap, this study fo-cuses on the swelling characteristics of bamboobased on its special structure. First, we comparedthe structural differences of wood and bamboo,and then, based on the gradient structure ofbamboo, we studied its swelling characteristics insolutions of different electrolytes.

MATERIALS AND METHODS

Materials

Bamboo specimens. Moso bamboo (Phyllos-tachys pubescensMazei ex H. de Lebaie) of 5 yrof age was collected from a bamboo plantationlocated in Anhui Province, China. All thespecimens used for the swelling experimentwere prepared from a height of 1.5 m above theground of the same moso bamboo culm. Carewas taken during the selection of bamboospecimens to reduce the influence of the varia-tion of the specimens itself on the experiment.The specimens were divided into two groups.Group one was a bamboo block with a finaldimension of 10 mm (L, longitudinal) � 10 mm(T, tangential) � t (R, radial; thickness of thebamboo culm wall) by split and was processedfurther. Group two was the group one blockfurther evenly divided into three pieces in theradial direction, namely, outer bamboo, inter-mediary bamboo, and inner bamboo with a di-mension of 10 mm (L) � 10 mm (T) � t/3.

The solutions were divided into nine types ofchemical reagents under three categories, eachof which (except for deionized water) consists ofthree different concentration levels, and eachconcentration level contains three specimens toreduce errors. So, there were 9 � 3 � 3 ¼ 81specimens in group one and 9� 3� 3� 3¼ 243specimens in group two. A total of 324 specimenswere used in the experiments.

Methods

SEM observation. The cross-sectional struc-ture of moso bamboo was observed by usinga scanning electron microscope (FEI-ESEM,XL-30, FEI, Inc,Hillsborough, OR). with an

accelerating proportion voltage of 7 kV. Forcomparison, the cross-sectional structures ofpoplar and Chinese fir were also observed.

Swelling experiment. Experimental reagentsinclude strong electrolytes: NaOH, Na2CO3, andNaCl; weak electrolytes: ice-cold acetic acid,quinine, pectase; and nonelectrolytes: deionizedwater, ethanol, and glycerin. The preparation ofthe solutions was carried out delicately at roomtemperature. More details of the nine types ofchemical reagents are shown in Table 1. Thespecimens from group one and group two weresoaked in the 27 types of prepared solutions insealed weighing bottles placed in a thermostati-cally controlled bath for 10 d at the temperatureof 25°C.

Data measurement. Specimens were oven-dried at 60°C for 24 h and then cooled in adesiccator; then the cooled oven-dry weights anddimensions were quickly measured. After theswelling experiment, specimen dimensions weremeasured again in a humid state, and then thecooled oven-dry weights after the swelling weremeasured after the specimens were dried in theoven at 60°C for 24 h. All the measurementswere made at room temperature by using amicrometer caliper accurate to �0.01 mm and ascale balance accurate to �0.01 g. To furtherimprove the accuracy of the measurement size,five points on the cross-section were selected asthe measurement points (one point is in thecenter and four points are in the four corners),and the average value was finally taken. Themaximum percentage swelling was calculatedby the use of the equation (Mantanis et al 1994a,1994b):

Maximumpercentage swelling

¼ Swollen dimension-Oven dry dimensionðOven dry dimensionÞ

� 100%:

Mass loss was calculated by the use of theequation:

Zhu et al—SWELLING CHARACTERISTICS OF BAMBOO 3

Mass loss

¼Oven dryweight-Oven dryweight after swellingOven dryweight

� 100%:

RESULTS AND DISCUSSION

Microstructure Differences between Bambooand Wood

Figure 1 shows the hierarchical structures ofbamboo. Obviously, bamboo is a unique annularculm with hollow structure (Fig 1(a) and (b)); itsouter surface was covered with wax, innersurface was covered with tabaxir, and its middlepart was composed of vascular bundles andparenchyma tissue (Fig 1(c)). Among them,vascular bundle consists of fibers (Fig 1(j)) andvessel (Fig 1(i)), and parenchyma tissue consistsof parenchyma cells (Fig 1(h)). Compared withChinese fir tracheid (Fig 2(b)) and poplar fiber(Fig 2(d)), fiber distribution on the cross-sectionof bamboo is not as uniform as that of wood,making its structure more special; moreover,moso bamboo fibers have almost no cell walllumen (Fig 1(j)).

Furthermore, the vascular bundles in bamboois also nonuniform along the radial direction.Based on this, bamboo can be divided into outerbamboo (Fig 1(e)), intermediary bamboo (Fig1(f)), and inner bamboo (Fig 1(g)) from theoutside to the inside, which is similar to thedifference between the early and late wood ofChinese fir (Fig 2(a)) and poplar (Fig 2(c)).The radial distribution of vascular bundles in

bamboo shows a graded hierarchical structure(Fig 1(d)).

Maximum Percentage Swelling of BambooBlock in Different Solutions

Most solutions seem to swell the bamboo to analmost consistent extent, although variations indifferent solutions did occur. Figure 3 is a graphof the swelling degree of the bamboo block indifferent solutions. Results indicated that sodiumhydroxide, glacial acetic acid, and ethanolswelled the bamboo block more than water, butsodium carbonate, sodium chloride, quinine,pectase, and glycerin were less capable than waterin terms of swelling bamboo. The largest amountof bamboo swelling was caused by sodiumhydroxide.

Mantanis et al (1994b) suggested that the strongbasic nature of solutes is significant for the degreeof swelling. This may explain that sodium hy-droxide resulted in the highest level of swelling ofbamboo because of its strong base with highchemical activity. The microstructure of bamboocan be understood in a way that the combinationof cellulose is the strengthened ligand, hemi-cellulose is the connecting substance, and ligninis the filling material, whereas extractives (ter-penes, fats, phenols, fatty acids, tannins, etc.) donot count as structural components. Sodiumhydroxide not only has strong chemical activity(Nguyen et al 2018) but also has a strong ex-traction influence on bamboo, especially forhemicellulose and extractives. Hemicellulose and

Table 1. Information of chemical reagents.

Experimentalreagents

Concentrationlevel

Molecularformula Purity Supplier

Sodium hydroxide 1%, 2%, and 4% NaOH AR Qiangsheng Biochemical Co. Ltd., Jiangsu, ChinaSodium carbonate 1%, 2%, and 4% Na2CO3 AR Qiangsheng Biochemical Co. Ltd., Jiangsu, ChinaSodium chloride 1%, 2%, and 4% NaCl AR Qiangsheng Biochemical Co. Ltd., Jiangsu, ChinaGlacial acetic acid 5%, 10%, and 20% C2H5COOH AR RichJoint Chemical Reagents Co. Ltd., Shanghai, ChinaQuinine 1%, 2%, and 4% C20H24N2O2 AR Macklin Biochemical Co. Ltd., Shanghai, ChinaPectase 1%, 2%, and 4% C20H43N AR Macklin Biochemical Co. Ltd., Shanghai, ChinaDeionized water 100% H2O EW-II Laboratory providedEthanol 25%, 50%, and 100% C2H5OH AR SuYi Chemical Reagent Co. Ltd., Shanghai, ChinaGlycerin 25%, 50%, and 100% C3H8O3 AR SuYi Chemical Reagent Co. Ltd., Shanghai, China


the extractive would dissolve partly when bam-boo is being soaked in the sodium hydroxidesolution, and the strong-acting force betweenmicrofibrils inside the cytoderm is weakened. So,

it is easier for the microfibrils to expand andswell, and both the degree of swelling and themacroscopic volume of the cytoderm will in-crease as a result. Similarly, glacial acetic acid

Figure 1. Gradient structure of moso bamboo.


and ethanol also have a strong extraction effecton the extractives, but not on hemicelluloses.Mantanis et al (1994a) reported that the removalof extractives has been found to enhance swellingsignificantly. In addition, it was found that theremoval of extractives from wood even with mildprocedures caused a large decrease in the acti-vation energy, Ea, which represents the energy

required to break the wood (Mantanis et al1994a). In other words, the removal of extrac-tives makes the network structure of the cell wallmore easily damaged by the invading externalmolecules. Compared with wood, bamboo hashigher extractives and hemicellulose content(Table 2), which indicated the removal of ex-tractives and hemicellulose may be more sig-nificant for bamboo swelling. Furthermore, thestrong swelling ability of ethanol compared withwater can also be explainable by its very highhydrogen-bonding capability. In addition, thesurface tension of ethanol (21.97 mN/m) is lessthan that of deionized water (72.00 mN/m) andglycerin (63.30 mN/m) at a temperature of 25°Cpossibly because it is easier for ethanol to go intothe interior of bamboo and participate in theexpansion of microfibrils. Similarly, as forglycerin, both its density (1.263 g/cm3) andviscosity (945 Pa$s) are higher than those ofdeionized water (1 g/cm3, 0.894 Pa$s) and eth-anol (0.789 g/cm3, 1.074 Pa$s), so it should bemore difficult for glycerin to penetrate the interiorof bamboo. Mantanis et al (1994b) suggested thatany increase in the molecular dimensions of the

Figure 2. Chinese fir and poplar structure.

Figure 3. Dimensional change of bamboo when soaked indifferent solutions.


liquid will cause a consequent increase in the Ea

of wood swelling, which may account for thestronger swelling ability of ethanol than glycerin,and similarly why sodium carbonate, sodiumchloride, quinine, and pectase are less capable inswelling wood. Nakatani et al (2010) andKucharczykova et al (2017) assumed that woodswelling was a bimolecular reaction merely re-quiring the collision of liquid molecules withwood. Because it is more difficult for largermolecules to enter the interior of bamboo, thedegree of bimolecular reaction is very low.

We can also find that the swelling ability of thesolutions do not correlate directly with its abilityto ionize, ie whether it is a strong electrolyte,weak electrolyte, or nonelectrolyte. As shown inFig 3, electrolysis (except sodium hydroxide) hasvery little effect on the swelling of bamboo.However, it is highly probable that more complexmechanisms are behind this phenomenon thatawaits further exploration.

Difference on the Longitudinal, Tangential,and Radial Direction of Swelling of Bamboo

Figure 4 shows the dimension change and thechange rate of longitudinal, tangential, and radialdirection of bamboo, which was soaked in dif-ferent solutions. It shows that the incrementsare mainly reflected in the tangential and radialdirection, but not in the longitudinal directionof bamboo blocks in any solution.In addition,the ratio of the tangential increment to radial

increment is between 0.32 and 0.54. The di-mensional change in the longitudinal directionwas more affected by the microfibril angle. Thereason why the longitudinal increment is less canbe explained by its much smaller microfibrilangle (about 9°) (Yu et al 2014). Normally, theratio of the tangential increment to radial in-crement of swelling of wood is 2, which isdrastically different from the data from thebamboo swelling experiment carried out in thisstudy (Sopushynskyy 2017). There may be tworeasons for this phenomenon. 1) Macroscopi-cally, bamboo is characterized by a hollowstructure (Fig 1(b)) with large tolerance inside theradial direction. Therefore, its congenital condi-tions allow for more radial increase to preventcracking. 2) Microscopically, as shown in Fig

Table 2. Chemical constituents of moso bamboo (Phyllostachys pubescen) and wood (Zhang et al 2005; Jiang et al 2006;Hong 2015; Meng et al 2016).

Cellulose % Hemicellulose % Lignin % Extractives %

Bamboo clocka 41.54 25.51 22.06 6.27Outer bamboob 45.27 22.04 27.90 5.23Intermediary bamboob 41.23 27.15 24.01 7.39Inner bamboob 39.01 24.01 23.68 7.18Bamboo parenchyma cellc 25.53 31.82 22.55 10.70Bamboo fiberc 46.74 20.93 20.83 5.06Poplard 52.83 19.50 21.77 2.64Chinese fird 47.40 10.65 32.94 4.31

a Meng et al (2016).b Jiang et al (2006).c Hong (2015).d Zhang et al (2005).

Figure 4. Dimension change and change rate of longitu-dinal, tangential, and radial direction of bamboo in differentsolutions.


1(d), the structure of bamboo results in hugevariations in the radial direction, which is mainlyreflected by the density and the size of the vas-cular bundles. Therefore, unlike the radial di-rection, the variation is smaller tangentially.

Differences between Maximum SwellingPercentage of Outer, Intermediary, and InnerBamboo in Different Solutions

The results of the maximum percentage swellingwith outer, intermediary, and inner bamboo indifferent solutions are shown in Fig 5. Resultsindicated that all agents are capable of swellingthe three separate parts of bamboo better thanthey do with the bamboo block. The largestamount of outer bamboo, intermediary bamboo,and inner bamboo swelling was caused by so-dium hydroxide, glacial acetic acid, and ethanol,which is similar to the results of the swelling ofthe bamboo block. In addition, the maximumswelling values for all solutions occur with in-termediary bamboo, followed by outer bambooand then inner bamboo.

The different extents of swelling of outer, in-termediary, and inner bamboo can be directlyrelated to its structure. Chuma et al (1990) re-ported the density of bamboo fibers is 1.57 g/cm3

and that of parenchyma cells is 0.45 g/cm3. Zhanget al (2017) suggested that the distribution densityof vascular bundles increased radially from theinterior to the exterior of the bamboo culm, whichis also be seen in Fig 1. Higher density means alarge proportion of vascular bundles exist in theouter bamboo and by contrast, lowest densitymeans a very small proportion of vascular bun-dles exist in inner bamboo. In other words, outerbamboo is more compact than inner bamboo.Mantanis et al (1994b) noted that the woodswelling rate increased dramatically with thedecreasing size of molecules. Nakatani et al(2010) also suggested that larger molecules en-counter difficulties in diffusing into the finecapillary structure of wood. Bamboo swellingseems to be a bimolecular reaction that requirescollisions between solute molecules and bamboomolecules; so, the structure of bamboo shouldhave a great influence on its swelling. Solventmolecules have difficulties in diffusing into the

Figure 5. Maximum swelling percentage of outer bamboo, intermediary bamboo, and inner bamboo in different solutions.


capillary structure of outer bamboo because of itshigh density and the existence of wax (Fig 1(c)).As for inner bamboo, the density of vascularbundles is lower because the tissue proportion ofthe fibrous sheath here is very small, and a largenumber of parenchymal cells are present inside(Zhang et al 2017). In fact, inner bamboo is veryloose because of its lower density; but solventmolecules also experience difficulties in diffusinginto it because of its tabaxir, which is coveredwith more lignin that prevents the invasion ofexternal particles. Mantanis et al (1994b) in-dicated that the cellulose polymer is possibly theprimary cause for the maximum extent of woodswelling. The swelling effect of outer bamboo isstronger than that of inner bamboo as a result ofits higher cellulose content, and that may also bedue to its greater density. There is no wax andtabaxir of intermediary bamboo; therefore, themolecules of the solvent can easily diffuse into itsstructure. So, intermediary bamboo swells thegreatest because it has an intermediate densityand lacks substances that hinder swelling. Theswelling effect of bamboo block is the poorestlikely because it has wax and tabaxir at the same

time. Therefore, for better effects, we suggest toremove the wax and the tabaxir before swellingbamboo.

Different Mass Loss of Outer, Intermediary,and Inner Bamboo in Different Solutions

Figure 6 shows the differences of the mass loss inouter, intermediary, and inner bamboo in dif-ferent solutions. All solutions seem to cause achange in the weight of bamboo, although theextent of the change varies among the bambooblock, outer bamboo, intermediary bamboo, andinner bamboo. The mass loss in outer bambooand the bamboo block is slighter than that inintermediary bamboo. In addition, there appearsto be an increase in weight in the specimenswhen being soaked in a strong electrolyte withhigh concentration, especially for intermediarybamboo.

Mantanis et al (1995a) indicated that the phe-nomenon of wood swelling is similar to achemical reaction. It is clear that the mass lossof bamboo is directly affected by its chemical

Figure 6. Different mass losses of outer bamboo, intermediary bamboo, and inner bamboo in different solutions (negativevalues relate to mass gain).


composition. Jiang et al (2006) showed that thecellulose content continuously decreases fromouter bamboo to inner bamboo, whereas thecontent of hemicelluloses, lignin, and extractivesshows a rising trend (Table 2), which is specu-lated to be linked with the distribution of fiberssimilar to its structural variation. Hemicelluloses,lignin, and extractives would dissolve partlywhen the bamboo specimens are soaked in so-lutions. For example, sodium hydroxide candissolve part of the hemicellulose and extractives(Sun et al 2013), and glacial acetic acid canpartially dissolve lignin and extractives (Wanget al 2017). But, such solutions generally haveless effect on the cellulose. The mass loss in outerbamboo and bamboo block is less than that ininner bamboo, which can be explained by itslarger proportion of cellulose (Table 2). There is aspecial phenomenon worth paying attention to,which is that bamboo specimens tend to dem-onstrate an increase in weight when the solution isa strong electrolyte with high concentration.Strong electrolytes are usually heavy metal salts,which are completely ionized in solution. Fol-lowing their entrance into the interior of bamboo,they can be recrystallized after drying, leading toa weight increase. The swelling effect of in-termediary bamboo is the most obvious becausemore molecules can enter into its structure.Consequently, the weight gain rate is the highest.Glacial acetic acid and ethanol are volatile and,therefore, do not cause any weight gain. Inconclusion, strong electrolytes are not suitable forswelling bamboo because of the side effect, iemass increase, caused by recrystallization.

CONCLUSION

The swelling characteristics of the bamboo block,outer bamboo, intermediary bamboo, and innerbamboo have been obtained in solutions of dif-ferent electrolysis. The extent of swelling ismainly influenced by two solution properties: thechemical activity that determines the ability of thesolution to interact with bamboo and the mo-lecular dimension that determines whether themolecules can enter the interior of the bambooor not. In addition, the dimension increase in

bamboo after swelling is mainly reflected in thetangential and radial direction, and the ratio of thetangential increment to radial increment is be-tween 0.32 and 0.54, which is drastically differentfrom the corresponding data from wood swelling.Furthermore, the largest dimension increasesoccur in intermediary bamboo, which can beexplained by the absence of wax in outer bambooand tabaxir in inner bamboo. Moreover, highconcentration of strong electrolytes will cause acertain degree of recrystallization in bamboo,especially for intermediary bamboo, resulting inan increase in its mass. In summary, we concludethat removal of wax and tabaxir before swellingand avoidance of using strong electrolytes asswelling solutions tend to improve the efficiencyof bamboo swelling.

ACKNOWLEDGMENTS

Wewould like to thank the Basic Scientific ResearchFunds of International Center for Bamboo andRattan (1632018016) and the 12th Five Years KeyTechnology R&D Program (2015BAD04B03) fortheir financial support for this research.

REFERENCES

Chuma S, Hirohashi M, Ohgama T, Kasahara Y (1990)Composite structure and tensile properties of mousoubamdoo. J Soc Mater Sci (Wroclaw) 39:847-851.

Hong H (2015) Chemical composition analysis and degra-dation of bamboo parenchyma tissue. Master Thesis.Central South University of Forestry Science and Tech-nology. 20 pp.

Ishimaru Y, Narimoto S, Iida I (2001) Mechanical propertiesof wood swollen in organic liquids with two or morefunctional groups for hydrogen bonding in a molecule.J Wood Sci 47(3):171-177.

Jankowska A, Drozdzek M, Sarnowski P, Horodenski J(2016) Effect of extractives on the equilibrium moisturecontent and shrinkage of selected tropical wood species.BioResources 12(1):597-607.

Jiang Z, Yu W, Yu Y (2006) Analysis of chemical com-ponents of bamboo wood and characteristic of surfaceperformance. Dongbei Linye Daxue Xuebao 34(4):1-3.

Kucharczykova B, Danek P, Kocab D, Misak P (2017)Experimental analysis on shrinkage and swelling in or-dinary concrete. Adv Mater Sci Eng (3):1-11.

Li R, XuW,Wang C, Zhang S, SongW (2018) Optimizationfor the liquefaction of moso bamboo in phenol using re-sponse surface methodology. Wood Fiber Sci 50(2):220-227.


Mantanis GI, Papadopoulos AN (2010) Reducing thethickness swelling of wood based panels by applying ananotechnology compound. Eur J Wood Wood Prod68(2):237-239.

Mantanis GI, Young RA, Rowell RM (1994a) Swelling ofwood. Wood Sci Technol 28(2):119-134.

Mantanis GI, Young RA, Rowell RM (1994b) Swelling ofwood. Part II. Swelling in organic liquids. Holzforschung48(6):480-490.

Mantanis GI, Young RA, Rowell RM (1995a) Swelling ofwood. Part III. Effect of temperature and extractives on rateand maximum swelling. Holzforschung 49(3):239-248.

Mantanis GI, Young RA, Rowell RM (1995b) Swelling ofwood. IV. A statistical model for prediction of maximumswelling of wood in organic liquids. Wood Fiber Sci.

Meng FD, Yu YL, Zhang YM, Yu WJ, Gao JM (2016)Surface chemical composition analysis of heat-treatedbamboo. Appl Surf Sci 371:383-390.

Nakatani T, Ishimaru Y, Furuta Y (2010) Swelling of woodcaused by organic liquids having relatively large molecularsizes. Mokuzai Gakkaishi 56(4):211-218.

Nguyen TD, Sakakibara K, Imai T, Tsujii Y, Kohdzuma Y,Sugiyama J (2018) Shrinkage and swelling behavior ofarchaeological waterlogged wood preserved with slightlycrosslinked sodium polyacrylate. J Wood Sci 64(5):1-7.

Sharma B, Gatoo A, Bock M, Ramage M (2015) Engineeredbamboo for structural applications. Constr Build Mater 81:66-73.

Silva ECN, Walters MC, Paulino GH (2006) Modelingbamboo as a functionally graded material: Lessons for theanalysis of affordable materials. J Mater Sci 41(21):6991-7004.

Sopushynskyy I, Kharyton I, Teischinger A (2017) Wooddensity and annual growth variability of Picea abies (L.)

Karst. growing in the Ukrainian Carpathians. Eur J WoodWood Prod 75(3):419-428.

Sun SL, Wen JL, Ma MG, Sun RC (2013) Successive alkaliextraction and structural characterization of hemicellulosesfrom sweet sorghum stem. Carbohydr Polym 92(2):2224-2231.

Tanaka S, Seki M, Miki T, Umemura K, Kanayama K (2017)Solute diffusion into cell walls in solution-impregnatedwood under conditioning process IV: Effect of temperatureon solute diffusivity. J Wood Sci 63(6):1-8.

Wang Q, Xiao S, Shi SQ, Cai L (2017) Mechanical strength,thermal stability, and hydrophobicity of fiber materialsafter removal of residual lignin. BioResources 13(1):71-85.

West H (1988) Kinetics and mechanism of wood-isocyanatereactions. Ph.D. Thesis, University College of NorthWales. 25 pp.

Xing D, Li J,Wang X,Wang S (2016) In situ measurement ofheat-treated wood cell wall at elevated temperature bynanoindentation. Ind Crops Prod 87:142-149.

Yu Y, Wang H, Lu F, Tian G, Lin J (2014) Bamboo fibers forcomposite applications: A mechanical and morphologicalinvestigation. J Mater Sci 49(6):2559-2566.

Zhang QH, Zhao GJ, Jie SJ (2005) Liquefaction and productidentification of main chemical compositions of wood inphenol. For Stud China 7(2):31-37.

Zhang H, Pizzi A, Lu X, Zhou X (2014) Optimization oftensile shear strength of linear mechanically welded outer-to-inner flattened moso bamboo (Phyllostachys pubes-cens). BioResources 9(2):2500-2508.

Zhang X, Li J, Yu Z, Hu Y, Wang H (2017) Compressivefailure mechanism and buckling analysis of the gradedhierarchical bamboo structure. J Mater Sci 52(12):6999-7007.


study on the swelling characteristics of bamboo based … · study on the swelling characteristics...

Documents