جستجوی مقالات مرتبط با کلیدواژه "bamboo" در نشریات گروه "صنایع چوب و کاغذ"

Decreasing of wooden raw material for industries has led to the development of non-wooden lignocellulosic resources such as fast-growing bamboo. In comparison with wooden species these non-wooden species are different, anatomically and chemically and their application mainly causes low quality composites. In this research different amount of industrial wood particles are replaced with bamboo particles (10, 20 and 30 percent). In order to improve the negative effects of presence of bamboo particles in the composites the polypropylene powder were used in two levels (5 and 10 percent). Different combinations of the aforementioned raw materials were manufactured in a hot press after being sprayed with UF resin. The physical and mechanical properties were evaluated according to European standards set of EN. Results showed that the maximum of MOR and MOE were found in the combination of 10 percent polypropylene and 20 percent bamboo. In addition, the increase in the amount of bamboo (30 percent) resulted in decrease in MOR and MOE. Increasing of bamboo has a negative effect on water absorption and thickness swelling after 2 and 24 hours but increasing of polypropylene from 5 to 10 percent had a positive effect on these factors. According to the results the composites manufactured of 20 percent of bamboo and 10 percent of polypropylene can meet the requirement of particleboards for carpentry to be used in dry conditions.

In this study, physical and mechanical properties of single layer particleboard made from bamboo powder (with and without alkali treatment) and wood particles were investigated. Bamboo powder (30 mesh particles) was treated with 5% hydroxide sodium for 120 minutes. Industrial wood chips from Sanate Choube Shomal Company were used.The variable in this research were the ratio of bamboo powder (with and without alkali treatment) to wood chips (at four levels; 0:100, 10:90, 20:80, 30:70). Urea formaldehyde resin used at 10 percent level of dry weight of raw material as well as ammonium chloride was used as a catalyst at 2 percent level of the dry weight of adhesive. Physical and mechanical properties of panels measured according to EN Standard. Mechanical properties of the particleboards made from treated bamboo was superior to the relevant untreated bamboo. Water absorption and thickness swelling after 2 and 24 hours immersion in water decreased with alkali treatment. Mercerization, or treating cellulose fibers in alkaline solution, because of fibrillation, the removal of lignin and hemicellulose enhances the mechanical properties and dimension stability of the particleboard by promoting resin-fiber mechanical interlocking at the interface. Results showed, there was usability of the treated bamboo up to 30 percent for general purpose boards for use in dry conditions.

This research and aim was using Bamboo and Reed CMP pulp for newsprint production. For this purpose, some chips of bamboo stem in the west of Mazandaran were randomly chosen. Then CMP Pulps were prepared at the yield 85%in 120 minutes(Bamboo) and 31 minutes(Reed), by using cooking conditions of Wood and Paper Industries of Mazandaran 60 gr/m2 newsprint handsheets were prepared from the Bamboo and Reed CMP and Mill(MWPI) CMP pulps, first in a separate and then mixed way with 25,50,75 percents. Then the optical and mechanical properties were measured and compared according by using TAPPI Standard test methods. The results showed that the most strength of the burst, breaking length, tensile, tear strength, yellowness and opacity were in the handsheets obtained from 100% the bamboo CMP pulp and the lowest strength (except brightness) was in Reed CMP pulp. The results also pointed out that the above-mentioned all strengths (except brightness) can be improved by using 25-100% of the bamboo CMP pulp, too. The results also indicated that 25-100% of the bamboo CMP pulp and 25% of the Reed CMP pulp can use for newsprint production.

The aim of this study was to investigate biometrical properties of bark، node and internode chemical components of Bamboo phyllostachys pubescens. The results showed، there were significant difference between fiber length of bark، node and internode; and internode had maximum fiber length and node had minimum fiber length. There were also significant difference between lumen diameter and cell wall thickness; and node had the highest value. In terms of chemical compositions; amount of extractives، lignin and ash of node were more than internode، but there weren’t significant differences at the 95% confidence، while the amount of cellulose of internode was significantly more than node. Slenderness ratio، flexibility ratio and Raunkel ratio were also calculated for bark 93. 06، 36. 641، 172. 916% and for node 46. 308، 33. 108، 202. 035% and for internode 88. 151، 31. 678، 215. 666% respectively. Generally the observations indicated that، according to the characteristics of the fiber of this nonwood plant، it can be recommended to produce pulp and paper.