Journal of Wood and Forest Science and Technology
Year:2016 | Volume:23 | Issue:2|Papers Count:21

Background and objectives: In this study, due to increasing of cardboard and paper products demand and consumption in Iran and also the important role of Mazandaran Wood and Paper Industries Company as a great supplier of paper products, the relative performance of the production units of this company was measured.Materials and methods: In order to do this research, required data for a period of 6 years (2005 up to 2010) and 6 production units was collected form the company financial balance sheets. Due to the importance of this company, dual input- oriented data envelopment analysis models was used to measure its efficiency.Results: The results indicated that this company in some production units (such as: newspaper, white kraft liner and fluting line 1) had a good efficiency score (%100 efficient or score 1). But, according to the input-oriented sample of these models and scale efficiency model (SE), the rest of production units were inefficient.Conclusion: Hence, this company must reduce its consumption of finical inputs (similar to efficient units) until it increases its scale efficiency of production units and profitability.

Background and objectives: In this study, effect of treatment of reed (Arondo donax) particles used in core layer of sandwich panel in three levels (untreated, heat treated and hot-water- treated particles), press closing time in two levels (5 mm/s and 9 mm/s) and almond shell powder/ melamine formaldehyde + urea formaldehyde resin ratio used in glue line in three levels (3: 97, 18: 82 and 33: 67) on the some physical and mechanical properties of sandwich panel were evaluated based on ASTM.Materials and methods: Reed particle with the 7% MC was used in core layer of sandwich panel. The manufacturing panels in two stages: producing core layer and veneering core layer with fir species was done. UF and MF resins with the 50: 50 weight ratio was used as binder. After gluing and forming cake, particles were transformed into the press. Temperature, time and pressure level applied by press were 180°C, 12min and 30 kg/cm2, respectively. After the core layer manufacturing and gluing the surfaces of upper and under veneers, the core layer was arranged between veneers and was pressed under 150°C, 120s and 0.2kg/cm2 press situations. After trimming, determination tests of modulus of elasticity, internal bonding, tensile strength of screw and nail and water absorption was done.The results were analyzed, statistically. It was used the Duncan's multiple range test in order to comparison of mean values.Results: panels manufactured from hot- water treated reed particles in core layer pressed with longer press closing time (5 mm/s) had the maximum MOR (15.6 N/mm2), tensile strength of screw (136.32 N/mm), nails (14.01 N/mm), dry internal bonding (0.26 N/mm2) and wet internal bonding (0.16 N/mm2).Conclusion: the almond shell powder/ melamine formaldehyde + urea formaldehyde resin ratio in glue line had no effect on the studied properties of panels, significantly, but it affected the bending strength, significantly. Besides, the type of treatment of particles used in core layer, and press closing time had effect on all of the panel properties, significantly. According to the obtained FT-IR spectral from specimens manufactured from different treated reed particles, hot-water- treated causes to increment of hydrogen bond quantities. Moreover, macroscopic photos showed that the hot-water-treated formed the best surface quality in order to create suitable chemical bond.

Background and objective: The paper industry in the world is encountered with raw cellulose material constraints. In many countries, wood in sufficient quantities does not exist on the pulp and paper industry needs. The rapid growth of paper consumption, causes raw materials shortages in the pulp and paper industry. The overall objectives of the pulp industry is to increase efficiency, reduce costs, development of environmentally friendly processes and improve the quality of products. The pulp and paper industries are increasingly growing and developing.The reports showed that sugars due to their abundance, small sizes (nanometer size) and substantial hydrogen bonding capacity can be considered appropriate substance in the paper industry. On the other hand, the paper strength varied with sugar type, sugar content in the final papers and the level of refining of the constituent fibers. This research was carried out to investigate the effect of using sucrose as an organic additive on bagasse soda pulp properties.Materials and methods: Bagasse soda pulp of pars haft Tapeh factory and sucrose solution (different concentrations of 5, 10, 15, 20 % based on dry weight of fibers) were used. Bagasse soda pulp was incorporated with sucrose solution in different concentrations, and were stirred in the mixer for 20 min. The hand sheets with base weight of 60±3 g/m2 were prepared according to TAPPI standard. The effect of using sucrose on optical, mechanical and physical properties of hand sheets were examined and compared to control sample, which was without sucrose.Results: The results showed a significant difference between control sample (sample without sucrose) and papers containing sucrose in terms of optical, mechanical and physical properties (p£0.01). With increasing of sucrose up to 15% by weight in the paper, density, air resistance, water retention value, tensile index, burst index increased while tear index, opacity and brightness decreased. The enhancement of paper strength with adding sucrose up to 15% is due to bonding hydrogen between hydroxyl groups of the sugar and those of the cellulosic lamellae of the cell wall.Conclusion: Overall, when the retained sucrose content in the paper reached a maximum of approximately 4% of the dry weight of paper, many hydrogen bonds formed between saturated fibers with disaccharide sugars and, this led to the strengthening fibers network in pulp and paper and improving the paper properties. Paper composites produced in this work can be used as absorbent paper, due to their high water retention.

Background and objectives: Cotton is one of the important non-wood plants that have been used for production of various cellulosic materials, banknote and other bond papers. Papers made from cotton have the better printability than papers made from chemical pulps. Quality of cotton fibers directly linked with commercial value. The quality of cotton fibers are evaluated with traits such as length, micronaire, elongation, strength, uniformity, color and trash. Since the uniformity of raw material quality is effective in uniformity of final products, therefore the quality of various varieties of cotton will directly be effective on final properties of paper. So the objective of this research is studying the quality traits of cotton fibers in varieties of Varamin, Doctoromomy and Khordad in dry regions of Iran to identify better varieties in bond paper production industry.Materials and methods: In order to qualitative and quantitative assessment of cotton fibers, the samples of cotton varieties from dry regions of Iran were chosen. In this Investigation various qualitative traits such as fiber length, elongation, strength, micronaire, uniformity, brightness, yellowness, moisture content, upper-half-mean-length (UHML) and Short-fiber content (SFC) of cotton were investigated. Experiments have been done by HVI instrument (ASTM D5869). A factorial experiment in a completely randomized design with 3 replicates for statistical analysis of qualitative traits of cotton was studied in SAS software. Means comparison was conducted by using Duncan's test.Results: Results showed that in studied cotton varieties, with increasing fiber length, all of the qualitative traits of fibers were significantly increased. In studied cotton, all of qualitative traits showed significantly difference except for micronaire. Doctoromomy variety has allocated better qualitative properties like highest fiber length, strength, elongation, uniformity, yellowness in comparison with the other varieties. Therefore, extending plant growing of Doctoromomy was recommended as a raw material for manufacturing bond papers.Conclusion: In this research, cotton variety of Doctoromomy due to suitable fiber length, lower SFC, very strong fiber strength, high uniformity and elongation is better variety for use in the process of Bond paper making. In a general conclusion based on the analysis performed in this study can be said that to improve the quality of cotton varieties chosen as the perfect solution not only based on the comments should be based on a set of qualitative traits of between them is necessary.

Background and objectives: The recent decline occurs in the Zagros oak forests, requires some studies and researches on the causes and its ways to develop. Review of trees and forest stands reactions, versus the phenomenon and its distribution in size classes of trees (diameter and height) is important to silviculturalists. This study aimed to investigate the relationship of trees with the risk of decline and the distribution in DBH and height of trees.Materials and methods: For this purpose, 12 stands of declined oak forests (Quercus brantii), in different conditions, have been conducted in Malehsiah forest site of Ilam province. In each of the stands, a transect line and in each transect 3 square plots of 2500 square meters were randomly determined. The data on the stands in the sample plots were measured and recorded. Data analysis carried out by ANOVA using appropriate software such as SPSS and Excel.Results: The results show that, except for the first diameter class (under 10 cm), a decreasing trend can be seen in the rest of the class. This trend reflects the uneven-aged stands. Trees size distribution suggests that about 86% of trees are less than 40 cm in diameter. The overall shape of the height distribution curve is normal with two humps. Tree size distribution suggests that about 70% of the trees are between 4 and 8 meters in height.Conclusion: Although a greater percentage of trees with bigger DBH and height have declined, but the distribution of declined trees is similar to the distribution of total trees and the decline can be seen in all classes. The analysis of the relationship between the diameter and height of the oak trees with degree of decline did not show any significant differences.

Background and objectives: Intraspecific competition between trees is a key interaction in shaping forest stands and makes analyzing the underlying ecological processes possible. This interaction may affect growth and spatial distribution of trees and result in a specific horizontal and vertical stand structure. For this reason, competition is known as one of the primary processes that influence population size, community structure and its diversity. In order to understand competitive interactions of trees in forests, several methods have been developed to assess spatial scale of competition among individual trees and show the effect of competition their biometric characteristics. Therefore, this study was aimed to investigate the effect of intraspecific competition between Persian oak coppice trees on their biometric attributes in Zagros arid and semi-arid forests using spatial analysis.Materials and methods: A 300 m × 300 m plot purely cover with Persian oaks was selected close to Yasuj city, Kohgiluye- BoyerAhmad province. The point map of all 1113 coppice trees was obtained by azimuth and distance technique. Kolmogorov-Smirnov test was primarily applied to investigate the difference between the distribution of coppice trees and homogeneous Poisson process. Spatial analysis of Persian oak coppice trees was then performed using pair correlation function g (r), O-ring function O(r), and mark correlation function kmm(r). In mark correlation function, biometric characteristics of total height, crown height, diameter at root collar, crown mean diameter and area were implemented as marks. Moreover, Monte Carlo test was used to test the significance of the results.Results: Comparison with homogeneous Poisson process showed that the observed pattern of Persian oaks was significantly homogeneous (a=0.05). The results of pair correlation function g(r), and O-ring function revealed that there was intraspecific competition between Persian oak coppice trees that was significant up to spatial scale of5 m (a=0.05). In addition, the results of mark correlation function demonstrated that total height, crown height, and diameter at root collar were very sensitive to intraspecific competition, while crown attributes (i.e. mean diameter and area) showed less sensitivity to competition.Conclusion: In general, it was concluded that there were competitive interactions between Persian oaks in the studied pure stand that negatively affected their biometric characteristics. Competition between coppice trees negatively influenced their growth, although this negative interaction had less effect on crown attributes as the distance between coppice trees because of their low density (123.7 coppice trees ha-1) reduced the crown competition.

Background and objectives: Survey and monitoring of forest areas in which silvicultural interventions were conducted over at least one decade and comparing of quantitative and qualitative characteristics of them with untouched stands could be a useful guide for planning the next interventions considering the goals of close to nature silviculture. Present research was carried out with the aim of studying the natural structure of oriental beech stands with emphasis on stem number in the first diameter class in order to obtain continued stability and adopting an appropriate silvicultural method in accordance with their structure and optimal management by better recognition of them especially surveying number of the trees in first diameter class (n10) as a sign of long-term sustainability of stands and planning for existence of enough numbers of this class in forest areas.Materials and methods: This study aims to compare the silvicultural characteristics between compartments 127 (managed) and 128 (unmanaged=control) in district one of Jahan-nama water catchment, Gorgan. Five sample plots, each one ha (100 x 100m), were laid out in each compartment, a total of 10ha, in random-systematic network. All of the trees with diameters above 5 centimetres inside the sample plots were harvested using the one hundred percent inventory method. To study the structure and regeneration rate of the stand, transects with a size of 100×10 metres were embedded in the middle of each plot in two directions. The heights of all existing trees in each compartment and other features such as canopy cover and quality of tree trunks were recorded in the related forms. Then, a 3×3 m micro plot was inserted inside each transect in 15m distances in order to study regeneration and the seedlings.Results: The results showed statistically significant differences of mean diameter and height of trees as well as regeneration number between the two studies compartments. Also, the frequency of stem number in the first diameter class (N10) of the managed compartment was 7 times higher than that of the control compartment. This difference was statistically significant. The results show that the highest difference in diameter classes is less than 15 cm, such that frequency of oriental beech species in the first diameter class (N10) in managed compartment is 4.5 times more than reserve compartment.Conclusion: Hence, the silvicultural interventions have led the managed stand to uneven-aged structure with sufficient stem number in N10, that with executing of silvicultural tending we could obtain sustainable stands. It will bring continued stability of forest stands with a wide presence of climax species (such as oriental beech) in the long term.

Background and objectives: To supply the raw material there are some limitations for pulp and paper mills in countries including low source of softwoods such as destruction, diminishing forest area, undeveloped forests, and the required budget to import long fiber chemical pulp (2). Required newsprint paper is prepared by the product of Mazandran wood and paper mill or trough imports. To produce newsprint paper in Mazandran wood and paper industry, chemi-mechanical pulp plant was devised base on Hornbeam (75%) and Beech (25%) species. Due to shortage of these species, the replacement of mentioned species with other sustainable and efficient wooden alternative species is necessary. Hence, the mill has substituted partial of its raw materials with Populus. Due to source restriction of Beech and Hornbeam wood, research on the possibility of the replacement of these specious with other species was necessary. The feasibility of using branch woods of Hornbeam and Beech in compound of hardwoods Stems Wood mixture on CMP pulp properties was investigated by other researchers (10).Furthermore, other research projects illustrated that utilization of Birch and Populus as part of raw material of Mazandran wood and paper mill with Hornbeam and Beech is possible (5,8). The aim of this research work was to explore the possibility of partially replacement of Beech and Hornbeam woods with other under management species of the mill. Therefore, the feasibility of substitution of four forest species (Oak, Maple, Alder and Persimmon) and two non-forest species (Willow and Populus) to replace with the raw material of the mill was investigated by this study.Materials and methods: The wooden species were gathered from forest and nonforest lands in the north of Iran and converted to chips by the chipper of Mazandran pulp and paper mill. Pulping stage was conduct by the cooking liquor of Mazandran pulp and paper mill. The various species were pulped via liquor to wood ratio of 7: 1 at 170 °C and at different cooking times (30-120 min) in order to achieve optimum yield (85 percent). To bleach, the chips were subjected to hydrogen peroxide. Then, the pulps were refined to freeness degree of 325±25 ml CSF. According to the TAPPI standard methods handsheets of 60 g/m2 were made. Optical and mechanical properties of the made papers were determined base on ISO standard methods.Results: The results of evaluating the strength and optical properties of the papers indicated that the best combination of species regarding to strength and brightness characteristics can be achieved by a mixture of 40% Populous, 45% Hornbeam and 15% Beech.Conclusion: For all treatments, tensile index, burst index, and tear index were elevated by increasing used percent of Populus. Although brightness level of the pulps was improved by augmentation the ratio of Populus, the opacity of papers dropped.

Background and objectives: Global development and higher living standards have caused people pay more attention to health and environment. Papers such as bills and printing and writing are daily exposing to a lot of among people; hence, were to important agents in the transmission of pathogenic microorganisms. Silver-nanoparticles are including antimicrobial agents that become oxidized in the presence of oxygen and light, and their structure is unstable. They also have a strong tendency to aggregation. The structural properties of nanoclay make it the perfect choice for removing deficiencies of silver-nanoparticles. According to the electrostatic adsorption of silver nanoparticles on the surface of clay, it is expected that increasing clay surface charge as a result of mill operation, lead to increasing the absorption rate of silver.Materials and methods: After milling clay from, sodium boron hydride reduction method was used to deposit silver-nanoparticles on the surface of clay (milled clay). SEM images were used to evaluate the effect milling on clay dimensions and Atomic Absorption Spectrometer and inductively coupled plasma- atomic emission spectrometry test to measure the amount of silver absorbed by the nanoclay in the production of silver-clay nanohybrid and silver-milled clay. The samples of paper were treated with both hybrids in three levels 10, 15 and 20 wt%. Antibacterial test was carried out by biophotometery. Distribution and the amount of present of nanohybrids in target papers were determined by FESEM-MAP images and elemental analysis (EDX) test.Results: The results showed that the amount of nanoparticles adsorbed on surface of clay was two-fold of milled clay, but during paper making because of more adsorption of silver nanoparticles on the surface of milled clay compared with the clay, that it has more absorption of pore, almost half of silver-nanoparticles were leaching. Antibacterial results obtained showed that the antibacterial properties of paper treated with both nanohybrids were high and growth rate of both types of bacteria (Escherichia coli, Bacillus subtilis and Staphylococcus aureus) significantly decreased.Conclusion: According to the results of FESEM, elemental analysis and antibacterial tests could be confirmed that, silver-clay nanohybrid can be used as an appropriate antibacterial agent in the paper. Also, due to superficial absorption of silver nanoparticles on milling clay compared with original clay, is better silver- milled clay nanohybrid to be used as a coating agent on the surface of the paper, so that using less nanosilver, creates higher antibacterial effect in paper that is efficient in terms of economic and environmental problems will follow lower.

Background and objectives: Zagross forests as the most extensive part of forests of Iran, retain important plant diversity. Vegetation knowledge is the base for ecological studies, management, and plant species conservation. Many diverse methods in vegetation studies have been proposed, based on the aims of study, kinds of vegetation, phonologic and taxonomic constraints, and financial and administrative possibility, which surveying is the most common. This study aimed to investigate the ability of modified multiscale Whittaker plots with random distribution in different vegetation types, in determining floristic composition.Materials and methods: In this study, floristic composition of Hashtad Pahloo forest catchment (8072 ha), contrary to common floristic studies, have been studied by sampling method using 21, 250 m2 Wittaker multiscale plots. Sampling plots were distributed randomly in four distinct vegetation types including pure oak type (Quercus brantii Lindl.), Mixed oak and Acer (Quercus brantii Lindl., Acer monspessulanum L.), Shrubs and cushion plants (Daphne mucronata Royle, Cotoneaster morulus Pojark), and Mountain grasslands (Ferulago angulata Boiss., Tanacetum polycephalum Sch. Bip) types. Collected plants species were identified using authentic references and their life forms were determined based on Raunkier classification. Also Chorological study were performed based on Zohari eco regional division. IUCN classification and red data book of Iran were used to define Conservative situation of plant species.Results: Results show that there are 211 species belong to 166 genus and 46 families in this landscape. Compositeae with 28 species (13.27%) were the biggest family. Irano-Toranian with 80 species (37.91%) and Mediterranean with 55 species (26.6%) were the most common chorologic types in this area. The most important life forms were Therophytes 88 species (43.9%), Geophytes 43 species (21.43%), Chamaephytes 25 species (13.2%), Hemicryptophytes 18 species (9.57%) and Phanerophytes 15 species (8.1%).Conclusion: Comparison of the results of this study with earlier floristic study recently performed in this landscape revealed that random distribution of sampling plots in different vegetation types is able to identify common plant species while it needs less time and cost.

Background and objectives: One of the new approaches in forest road network and skid trail planning is to find suitable terminals in the harvest units and after that planning a road network that optimally connects the terminals. The paper describes a methodology for finding the most economical landing location.Materials and methods: The methodology formulates each harvesting unit as a network problem. Each grid cell that identified as an individual entry node in the network, containing two attributes of the elevation and the timber volume. The exit points of the network are the landing nodes where are candidated based on the terrain slope by the planner. Each entry node were connected to the supposed landing nodes by a direct link. In the present research an economical place for landing location was defined as a point that makes the most volume of stock in access through the shortest distance and slope. The heuristic algorithm, then, calculated two parameters for each landing node: 1) the degree of attractivity as a function of the number of covered nodes, their volume of stock and their distance to the landing, and 2) the average slope of the links. The economical location for landing then was selected. The entire area of the compartment was supposed as the harvesting unit. In addition, the uphill and downhill skidding were included in the program.Results: The program was implemented for four candidate landing location in the compartment 423 of district 4 (Shiva dareh) in the educational and research forest of Tarbiat Modares University in the northern Iran. The results showed that the point “B” with an attractivity value of 5585.79 and an average slope of 10.41% was designated as the most economical point for landing the timbers.Conclusion: The present code could be used as an appropriate tool to propose the economical places for landing location where are assumed as desirable terminals in forest road planning within cut blocks.

Background: Increasing need for wood and wood resource depletion caused and exacerbated by the fast-growing plantation species. One way to avoid excessive harvesting of these forests could be growing plantation species series harvest age Economic is the age that the maximum value of the current or the current economic value is today in terms of reach. One of the trees in recent decades for afforestation with short harvest period, especially in South East Asia is considered different species paulownia. Under normal circumstances a ten-year paulownia tree size 40-30 cm diameter at breast height and volume choebdeh between.0.3-0.5 cubic meters per year and the best environmental conditions for the operation of timber trees produce 5-6 years. The development of paulownia planted by farmers in Sri Lanka indicated that the net present value at an interest rate of 7.5 percent paulownia planted 4627721 rupees and 3.28 benefit to cost ratio and internal rate of return is 28.34 percent. The aim of this study was to determine the most appropriate age paulownia planting harvest biomass forestry projects in the province according to the Dr Bahram-nia maximum economic value in each in each of the spacing is studied.Materials and methods: For this study, a 18-year-old Paulownia fortunei plantation was selected which was located in compartment two of series one of Dr. Bahram- nia Forestry Plan (Shastkalateh Gorgan). Three spacing of 3*6, 5*8 and 6*10 meter were examined. Five sample trees were chosen from the list of dominant trees of each spacing plantation. After felling of the selected trees, sample discs were cut from trunk height of.4 and 1.3 meter and 2 meter interval to tree top. Also, stand volume were calculated at different stand ages using form factor. In the next stage, the optimum harvest age (economic criteria) was determined on the basis of the stumpage values. Also, revenue and costs and net present value of the project were estimated at the optimum harvest age. Also, revenue and costs and net present value of the project were estimated at the optimum harvest age.Results: Results showed that Optimum harvesting age (economic criteria) were distinguished 8, 9 and 10 years for 3*6, 5*8 and 6*10 meter plantation spacing considering 12 percent interest rate and 750 Rials per kilogram price of stumpage wood. Result also showed that changes in wood prices do not affect on optimum harvesting ages of stands while increasing or decreasing interest rates will change optimum harvesting age, indirectly.

Background and objectives: Allocating of land to different land uses is very vital and important task that can considered by natural resource specialists and managers. There are different methods to evaluating a land allocation project. In some methods ecological capability evaluation is considered to land allocation and some methods are based on cost benefit analysis of different land uses. Agro forestry as a land use strategy has variety of advantages. This land use system can provide farmers with higher levels of income and welfare and increase protection of soil and water resources, simultaneously. In rural area, agro forestry systems can improve income of households which in return could reduce degradation of natural resources. Farmers need to be aware of preferences of agro forestry systems against normal agriculture. This can help managers to promoting this land use strategy in rural area. For this aim, net income of agro forestry and normal agriculture must be compared.Materials and methods: This study was conducted to compare agroforestry system and normal agriculture economically. Research was carried in Azna region located in Lorestan province. Data of study was gathered using survey and literature review. Supplementary data are obtained through different sources including field observations and discussion with extension officers at the divisional agricultural service. For this aim, a questionnaire based method was used to gathering data. Totally, 30 farmers who have agro forestry system and normal agriculture farms were selected randomly. All date about different costs and incomes of both of systems were gathered and costs and incomes were calculated. The data were analyzed using the Statistical methods.Results: Results of study indicate that costs and net incomes of agro forestry systems are higher than normal agriculture, statistically. Rate of return in agro forestry systems was higher than normal agriculture, statistically.Conclusion: The findings of research indicate that agro forestry can improve income of household and result in increasing of welfare level.

Background and objectives: Efficient use of waste papers and improve their quality has always been one of the targets in the pulp and paper industries. This study aimed to compare two stages bleaching of deinked pulp of newspaper and Magazine recycled pulp mixture using Sodium Dithionite (Y) and hydrogen peroxide (P).Materials and methods: Firstly, the pulp was bleached using 1% hydrogen peroxide and in the next stage bleaching was performed using 0.5 and 0.75 percent dithionite and of hydrogen peroxide Respectively for 60, 90 and 120 minute.Results: The results showed that with increase dosage of hydrogen peroxide in the second stage of PP sequence, decrease in bulk, opacity and increase in strength properties wasn't significant but increase in brightness and effluent COD showed significant changes. Prolongation of bleaching time in the second stage of PP sequence cause significant reduction in bulk, opacity and increase of effluent COD, brightness and strength properties. with increase the time of bleaching reactions in second stage of PY sequence, bulk and opacity reduction and increase in strength properties and brightness wasn't significant, but with chemical dosage increasing, just brightness increasing was significant. Also, according to the results, with increase of chemical dosage in second stage of PY sequence, increase in the amount of Effluent COD load wasn't significant, but with increasing of time of bleaching reactions in second stage of this sequence, increase in the amount COD load was significant.Conclusion: Regarding to the results, effluent's COD, brightness level and strength properties of PP sequence was higher than PY while bulk and opacity of that was lower than PY ones.

Background and objectives: Wood plastic composite product are a new group of composite materials that in comparison with products such as particleboard and plywood not old and are placed in the group new products. This group of composite considering to their wide range, has provided the groundwork for researchers, nowadays. Since the a major part the combination of these composites to wood and lignocellulosic material was constitute and given that wood and lignocellulosic material are prone to decay, so This research with aim of evaluation the effect of nano clay and Maleic anhydride modified polypropylene maple coupling agent material on physical, mechanical and natural durability of composite from polypropylene/ Haloxylon wood flour against the Coriolus Versicolor were investigated.Materials and methods: For this purpose Haloxylon wood flour with 50 percent weight ratio were mixed with polypropylene. Maleic anhydride modified polypropylene maple coupling agent material at two levels 0 and 3 percent and nano clay at four levels 0, 2, 4 and 6 percent used as variable factors. Material mixing process into the extruder device and test specimens were made using the method of injection molding. The test specimens placed for 14 week exposed to Coriolus Versicolor according to EN113 standard with 25 °C temperature condition and 75 percent relative humidity. Finally the amount of mass loss, strength and modulus of bending, impact resistance, water absorption and thickness swelling of wood plastic composite in two state of before and after decay were determined. For morphological study of composite from X-ray diffraction was used.Results: The results showed that with increasing nano clay mass loss, impact resistance, water absorption and thickness swelling were decreased but strength and modulus of bending of composites were increased. Beside with increasing the coupling agent, mechanical strength were increased but the mass loss, water absorption and thickness swelling were reduced. Structural studies of nano composites indicated that distribution of nano clay particles in matrix were Intercalation and with increasing the amount of nano clay up to 4 percent the spacing in nanolayered silicates were increased and with further increasing of nano clay particles up to 6 percent the distance between these layers were decreased.Conclusion: the use of nanoclay and Maleic anhydride modified polypropylene maple coupling agent material the one hand resistance to decay and natural resistance of wood plastic composite against of the white rot Coriolus Versicolor will be a significant increase and on the other hand prevent from a significant reduction physical and mechanical properties of this composite by fungal attack.

Background and Objective: According to the literature, cellulose nanostructures possess much better properties compared to cellulose microstructures. One of promising products previously made from cellulose nanostructures is nanocellulose sheet or nanopaper. All fabricated nanocellulose sheets had thickness below 100μm, but in this study, nanocellulose board was made purely from cellulose nanofibers, for the first time. Then, the physical properties of specimens including dimensional and density changes during fabrication process and long-term water absorption and thickness swelling behaviour were investigated. The performance of pre-pressing system was also investigated.Materials and Methods: Cellulose nanofibers or nanocellulose (NC) were provided from Nano Novin polymer Co. (Iran). The NC-board has been produced through a wet process without using resin. To make NC-mat, a special pre-pressing apparatus was designed and fabricated containing piston and cylinder made of polyethylene as main components. Piston made pressure on the NC gel in the cylinder and the water inside the gel went out through a screen with mesh size of 300, resulted in NC-mat. During vacuum oven drying at 70 °C for 24 h, NC-board was produced. The board was cut to proper sizes (2.8× 20 ×20 mm) for long-term water absorption and thickness swelling tests.Results: The results of using pre-pressing system showed that the gel concentration increased from 6 wt% to 40 wt% and mat thickness and density reached 5.5 mm and 0.54 g/cm3 (based on dry weight of NC), respectively. After drying in vacuum oven, the thickness and density of the board obtained 2.8 mm and 1.35 g/cm3, respectively. The results of water absorption and thickness swelling during 240 hours demonstrated that these properties rapidly increased to 52% and 44% respectively over 24 hours immersion in water and then did not show significant changes over immersion time longer than 24 hours.Conclusions: The performance of pre-pressing system was quite suitable to make nanocellulose mat with desirable properties. Since cellulose nanofibers are super absorbent material with high specific surface area, the values of water absorption and thickness swelling increased during the first 24 hours and then the values were not changed significantly over immersion time longer than 24 hours.