Comparisons and Characteristics of Slicewood Acetylation with Acetic Anhydride by Liquid Phase, Microwave, and Vapor Phase Reactions

Yang, Chen-Ning; Hung, Ke-Chang; Wu, Tung-Lin; Yang, Tiankui; Yong-long, Chen; Wu, Jyh‐Horng

doi:10.15376/biores.9.4.6463-6475

Cited by 11 publications

(8 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Acetylation as a common modifi cation method to achieve an improvement in particleboard properties, like dimensional stability (Yang et al, 2014;Rowell et al, 2009) or durability (Papadopoulos, 2012;Alfredsen et al, 2013), involves the formation of a covalent bond between the hydroxyl groups of the cell wall polymers of wood and reagent molecules. In order to achieve this, an adequate modifi cation intensity, meaning the relative amount of modifi cation agent added as weight percent gain (WPG), is required (Thybring, 2013).…”

Section: Uvodmentioning

confidence: 99%

Effect of Press Cycle Time on Application Behavior of Board Made from Chemically Modified Particles

Ghorbani

Bavaneghi

2016

Drvna ind.

View full text Add to dashboard Cite

Utjecaj trajanja ciklusa prešanja na ponašanje u primjeni ploče izrađene od kemijski modificiranih čestica Received -prispjelo: 12. 12. 2014. Accepted -prihvaćeno: 29. 1. 2016. UDK: 630*863.215 doi:10.5552/drind.2016 mechanical behavior was investigated as well as the decay resistance of acetylated particleboards. Original scientifi c paper • Izvorni znanstveni rad MATERIALS AND METHODS MATERIJALI I METODE Acetylation AcetilacijaFlakes were prepared by using a laboratory ring fl aker (Pallmam pz8) from maple wood (Acer insigne). They were dried in the oven for 24h at 103±2 °C. After 12h soaking in the acetic anhydride, the fl akes were heated at 120 °C for 40 and 180 minutes to achieve 9 and 16 % weight gains, respectively, (based on pre-test results). Modifi ed fl akes were washed with distilled water to remove acetic acid as the reaction by-product and unreacted acetic anhydride. Acetylated particles were dried in the oven at 103±2 °C for 24 h. Weight percent gain (WPG) was calculated using the equation (1). (1) Where WPG indicates the weight percent gain (%), W act and W unt are oven dry weights after and before the acetylation (g), respectively. OH group's substitution was determined according to equation (2) mentioned in the paper of Li et al. (2011). (2) Where OH substd indicates substitution of OH with acetyl groups (mmol/g), W act and W unt are oven dry weights after and before the acetylation (g), respectively. M w is the molecular weight of the adduct acetyl (-C (O)-CH 3 ) group (g/mmol). FTIR analysis 2.2. FTIR analizaThe Fourier transform infrared (FTIR) spectra were measured by using a Bio-rad spectrometer FTS-40 incorporating a Spectra Tech diffuse refl ectance accessory unit. For FTIR analysis, dried acetylated fl akes were milled and passed through a 40 mesh sieve. Spectra were obtained directly from wood powder on a detector prism. Manufacture of boards 2.3. Proizvodnja pločaParticles with size of 20-40 mesh were used for making the particleboards. After being blended with melamine urea formaldehyde (MUF) resin (10 % based on the oven dry weight), the single layer mats were pre-

show abstract

Section: Uvodmentioning

confidence: 99%

Effect of Press Cycle Time on Application Behavior of Board Made from Chemically Modified Particles

Ghorbani

Bavaneghi

2016

Drvna ind.

View full text Add to dashboard Cite

show abstract

“…Improvements of technical performances (dimensional stability, fungal degradation) have been observed, but the cited studies used sapwood as samples (Yang et al 2014;Iwamoto and Itoh 2006;. Authors Chang and Chang (2001) also used sapwood samples, but they carried out extraction before treatment to remove extractible fraction and after to remove unreacted anhydride.…”

Section: Introductionmentioning

confidence: 99%

Maleic Anhydride Treated Wood: Effects of Drying Time and Esterification Temperature on Properties

Essoua¹,

Blanchet²,

Landry³

et al. 2015

BioResources

View full text Add to dashboard Cite

To improve technical performance of wood siding, treatment with maleic anhydride was applied. The effects on technical performance of drying time and esterification temperature parameters were analyzed. Wood samples of lodgepole pine and white pine were treated and tested. Results indicated that treatment improves technical performance of wood (dimensional stability, fungal degradation resistance, and accelerated aging). FTIR spectroscopy analysis showed spectra with peaks at 1750 to 1730 cm -1 . These correspond to ester bonds formed between wood hydroxyl groups and MA carboxylic acid groups. SEM images indicate that the MA quantity in wood cavities was increased with decreasing esterification temperature. Weight percent gain (WPG) increased with decreasing time and temperature of esterification. Artificial aging and fungal degradation performances were monitored using FTIR analysis. Esterification temperature had no important effect on fungal degradation. Weight loss after fungal exposure of treated samples was not only due to fungal action but also due to evaporation of MA during the drying step. Regarding artificial aging, degradation of wood components and ester bonds were less for samples esterified at 180 °C than those esterified at 160 °C or 140 °C.

show abstract

“…At the end of the reaction, the acetylated samples were washed with distilled water and Soxhlet-extracted with acetone for 8 h. Finally, the acetylated samples were dried at 105 °C for 12 h, and the oven-drying method was used to calculate the weight percent gain (WPG) of the acetylated samples. In addition, for comparison purposes, a conventional acetylation process with AA by vapor phase reaction was also performed in this study, following the detailed procedure described in our previous study [ 10 ].…”

Section: Methodsmentioning

confidence: 99%

“…The conventional acetylation process is not only time-consuming, but also requires large quantities of the modifying agent. According to Yang et al [ 10 ], wood acetylation with AA using a vapor phase reaction could reduce the reagent consumption. However, using AA as a reactant has a main drawback of generating acetic acid as a by-product during the reaction, which results in undesirable odors and is difficult to remove from wood after acetylation due to its high boiling point (ca.…”

Section: Introductionmentioning

confidence: 99%

Characterization and Thermal Stability of Acetylated Slicewood Production by Alkali-Catalyzed Esterification

Hung

Yang

et al. 2017

Materials

Self Cite

View full text Add to dashboard Cite

This study was compared and characterized two different alkali (potassium carbonate (PC) and potassium acetate (PA))-catalyzed acetylations of slicewood with vinyl acetate (VA) by a vapor phase reaction. The results revealed that the esterification reaction between VA and the hydroxyl groups of slicewood could be improved by using PC or PA as a catalyst. Additionally, a significant weight percent gain was obtained after VA acetylation with 5% of catalyst. Furthermore, the reactivity of the cellulose hydroxyl groups for VA acetylation was more pronounced at the C2 reactive site compared to acetylation with acetic anhydride. On the other hand, the apparent activation energy of thermal decomposition between 10% and 70% conversion is 174–183, 194–200, and 183–186 kJ/mol for unmodified slicewood and VA-acetylated slicewood with PC and PA, respectively. Accordingly, the thermal stability of the slicewood could be effectively enhanced by VA acetylation, especially for using the PC as a catalyst.

show abstract

Comparisons and Characteristics of Slicewood Acetylation with Acetic Anhydride by Liquid Phase, Microwave, and Vapor Phase Reactions

Cited by 11 publications

References 21 publications

Effect of Press Cycle Time on Application Behavior of Board Made from Chemically Modified Particles

Effect of Press Cycle Time on Application Behavior of Board Made from Chemically Modified Particles

Maleic Anhydride Treated Wood: Effects of Drying Time and Esterification Temperature on Properties

Characterization and Thermal Stability of Acetylated Slicewood Production by Alkali-Catalyzed Esterification

Contact Info

Product

Resources

About