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Pineapple leaf fibers (PALF) were biopulped using Trametes versicolor, and the resulting biopulp was bleached with xylanase-enzymatic treatments. The biopulping was extensively described using determinations of fiber morphology, color, chemical composition, extractive content, and thermal stability using the structural characteristics determined by XRD and paper properties. The results showed that the chemical and enzymatic treatments shortened the fiber, almost to 50%, and the Kappa index decreased from 27 to 13. Cellulose and holocellulose contents increased from 65% to 74% and from 86% to 91%, respectively, but extractives, lignin (from 12% to 4%), pentosans (from 25% to 14%) and the crystallinity decreased from 58% to 67% in both chemical bleaching and further xylanase-enzymatic processing. Xylanase)enzymatic processing allowed us to obtain whiter (increased lightness color and decreased redness and yellowness tonality) and heavier paper, even though it presented decreased mechanical properties (decreased stress resistance, rupture length, tear resistance and index longitudinal tearing). The xylanase-enzymatic treatment with the best pulping and paper proper)ties is when the biopulp is treated with a xylanase enzyme concentration of 0.04% (w/w). [ABSTRACT FROM AUTHOR]

Terminalia catappa fibre dimensions were evaluated as raw material for pulp and paper production. Sapwood samples of T. catappa were collected from five matured trees with diameter at breast height (dbh) of 1.82m, 1.57m, 1.02m, 1.05m and 0.76m from stem portions of top, middle and base portions, respectively within Makurdi metropolis. The samples were air dried and sliver of 1cmx2cmx2cm dried sapwood were macerated in a test-tube containing equal volume of acetic acid and hydrogen peroxide in ration 1:1 at 100oC for 24 hours. Macerated solution of fibre was dropped on a slide and mounted on a Zeiss light microscope (standard 25) under 80 xs. Fifteen straight and unbroken fibres were randomly selected to the fibre dimensions. Derived indices were determined with standard formula. Fibre lengths of T. catappa ranged from 0.72 - 1.80mm. Fibre diameter was between 20.76µm and 16.25µm; mean lumen width ranged from 12.78µm - 8.35µm while mean cell wall thickness were 3.85µm - 6.28µm at different dbh and stem portions. Means of all fibre dimensions were not significant (p>0.05). Results on fibre indices ranged from 0.65 - 1.05 in Runkel ratio; 34.53% - 60.09% elasticity coefficient; 16.07% - 32.89% in rigidity coefficient; 22.00 - 36.73 in slenderness ratio; 0.37 - 0.47 in Luce's shape factor; 39.20 - 64.22 in F factors and 236.71in - 296.15in Solid factor. Means of all derived fibre indices were not significant (p>0.05). Results obtained have substantially proved Terminalia catappa to be very good raw material for pulp and paper production. [ABSTRACT FROM AUTHOR]

Terminalia catappa fibre dimensions were evaluated as raw material for pulp and paper production. Sapwood samples of T. catappa were collected from five matured trees with diameter at breast height (dbh) of 1.82m, 1.57m, 1.02m, 1.05m and 0.76m from stem portions of top, middle and base portions, respectively within Makurdi metropolis. The samples were air dried and sliver of 1cmx2cmx2cm dried sapwood were macerated in a test-tube containing equal volume of acetic acid and hydrogen peroxide in ration 1:1 at 100oC for 24 hours. Macerated solution of fibre was dropped on a slide and mounted on a Zeiss light microscope (standard 25) under 80 xs. Fifteen straight and unbroken fibres were randomly selected to the fibre dimensions. Derived indices were determined with standard formula. Fibre lengths of T. catappa ranged from 0.72 - 1.80mm. Fibre diameter was between 20.76µm and 16.25µm; mean lumen width ranged from 12.78µm - 8.35µm while mean cell wall thickness were 3.85µm - 6.28µm at different dbh and stem portions. Means of all fibre dimensions were not significant (p>0.05). Results on fibre indices ranged from 0.65 - 1.05 in Runkel ratio; 34.53% - 60.09% elasticity coefficient; 16.07% - 32.89% in rigidity coefficient; 22.00 - 36.73 in slenderness ratio; 0.37 - 0.47 in Luce's shape factor; 39.20 - 64.22 in F factors and 236.71in - 296.15in Solid factor. Means of all derived fibre indices were not significant (p>0.05). Results obtained have substantially proved Terminalia catappa to be very good raw material for pulp and paper production. [ABSTRACT FROM AUTHOR]

A sustainable development requires the use of bio-based packaging materials because of ready availability and limited environment impact. The porous structure and hydrophilic nature of cellulose in paper based materials needs to be combined or laminated with other materials to overcome these limitations. The fiber found in the banana stems and leaves, it is possible to use these raw materials in pulp processing and banana flour can be produced into an edible film. The aim of the study was to discover a suitable method (wet lamination or dry lamination) for producing paper (stems, leaves, or a 1:1 ratio of mixed stems and leaves) lamination with banana film and to study their physical properties for packaging application. Banana flour (4%) solution was used as adhesive media between paper and film for wet lamination process where as the heating and compression were applied for dry lamination process. The results showed the efficiency of banana stems for paper production. However, there was an improvement in results when a 1:1 ratio of mixed stems and leaves was used due to an increase in tensile strength, elongation, and the L value. There was no significance in the water vapor permeability in all treatments. All treatments of paper lamination expressed 6 - 13% moisture content. The separation of film and paper layers occurred in dry lamination samples. The wet lamination of the leaf paper and mixed paper caused high tensile strength and elongation. Therefore, it could be used as an alternative and environmentally friendly method in the application of packaging materials. [ABSTRACT FROM AUTHOR]

With the increase in demand for wood and wood products, there is need to find alternative sources for the production of pulp and paper. Non wood plants have attracted interest due to their short growth cycles, moderate irrigation and fertilizer requirements and low lignin content. This study aimed at investigating the fibre characteristics of Agave sisalana for pulp and paper production. Leaves were collected from three sisal plant stands in Oyo State, Nigeria. The plant whorl was divided systematically into bottom, middle and top from which five leaves were randomly collected from each whorl position. The fibres of the leaves were extracted from which 2cm of fibres were taken from three positions on the leaf (top, middle and base). Extracted fibres were macerated and 3375 fibres were measured. The result shows that the fibre length of sisal increased with increasing length of the leaves from base to top with a mean value of 1.68mm. The fibre diameter and cell wall thickness averaged 16.98µm and 2.32µm respectively decreasing from the stem base to the top. The slenderness ratio averaged 99.4 while the coefficient of flexibility averaged 72.61. The highest value of the runkel ratio of Agave sisalana was 0.42. The fibres from sisal (Agave sisalana) leaves possess good fibre dimensions and derived values which will make it suitable for the production of high quality paper. [ABSTRACT FROM AUTHOR]

Newly developed packaging paper made of biopulped pineapple leaf fiber (PALF) and poly(lactic acid)(PLA) was studied. PALF packaging sheets were solvent impregnated with PLA at different concentrations in order to improve their moisture barrier and mechanical performance. With the impregnation of PLA at a concentration of 4%, the packaging material exhibited a low moisture uptake and a high tear index. An electron micrograph of the sample at 4% impregnation revealed uniform and packed PLA reversed microsphere morphology. These results suggest that surface coating via biodegradable polymers, such as PLA, may be utilized for manufacturing packaging materials in industrial applications. This new packaging material could reduce the dependency on woodbased paper and plastic-based packaging. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the influence of acetylation on properties of paper made using the chemi-mechanical pulp (CMP) process. Industrial unbleached CMP pulp was provided (before and after refining), and paper handsheets were made. After drying, the specimens were acetylated on a heated cylinder at 120 °C, with acetic anhydride without catalyst. Physical and mechanical properties including water absorption, porosity, printability, brightness, D-folding, breaking length, tear resistance, and burst strength of samples were measured and compared between treated samples and the controls. The results showed that acetylation intensity was increased by increasing reaction time. Water absorption exhibited a significant reduction due to acetylation. Brightness, D-folding, and burst showed an increasing trend as a function of the degree of acetylation. Tear resistance was decreased by acetylation. The refining process improved acetylation and decreased porosity. The results indicated that most of the important factors were significantly influenced and improved by both acetylation and the refining process. [ABSTRACT FROM AUTHOR]

Biomaterials from olive tree pruning are an abundant agricultural residue in various Mediterranean regions. A suggested use of this residue is its separation in a main fraction (trunks and stems with diameter > 1 cm) and a residual fraction (leaves and stems with diameter 1 < cm), using biorefinery procedures. The main fraction is cooked with ethanol, giving rise to a pulp, which can be used either in paper or in bioethanol production if before pulping the main fraction is subjected to a hydrothermal treatment. Pulping with 70% ethanol concentration, 185 °C for 80 min resulted in a pulp with a yield of 46.30% and a content of holocellulose, α-cellulose, and lignin of 77.17%, 62.49%, and 21.73%, respectively. The paper sheets obtained had a breaking length of 1168 m, a burst index of 0.44 kN /g, a tear index of 2.25 mN.m²/g, and a brightness of 43.66%. The pulp converted into bioethanol (by simultaneous hydrolysis and fermentation) achieved a conversion of 70 g bioethanol/100 g potential bioethanol. The residual fraction of olive tree prunings was subjected to combustion to produce thermal energy. The heating value was 18700 kJ/kg, the flame temperature range was 1094 to 2013 ºC, and the dew point temperature range of the flue gases was 47 to 53 °C. [ABSTRACT FROM AUTHOR]

Abstract: This paper is concerned with the temperature field produced by a thermal printer head. Such heads are used to provide high quality prints of electronically stored images. In this system, a thin dye-layer, sandwiched between two copolymer sheets, is heated by a thermal head and dye diffuses into the receiver sheet producing a small dye-dot. The picture is made up of a large number of such dots. The basic aim is to determine the amount of dye which is eventually diffused into the receiver sheet when the heating is turned off and the system has cooled down. However, the amount of dye which diffuses into the receiver sheet depends on the temperature field because the diffusion coefficient is a sensitive function of temperature. In the thermal printer system, each head is heated by an electric current which is carried by gold leads. In this paper, we show that the heat loss through these leads has an important effect on the temperature field produced by the head and therefore, strongly influences the amount of dye transferred. [Copyright &y& Elsevier]

Porapak has been studied as a solid-food simulant in experiments on paper and board packaging. Three samples of paper with different recycled pulp content and surface treatment, and of different grammage and thickness, were used for the studies. Kinetic behaviour from 25 °C to 100 °C and different contact times ranging from 5 min at 100 °C to 10 days at 25 °C were studied using Porapak or, occasionally, Tenax or milk powder. Similar results were obtained with Porapak and Tenax but those from Porapak were more stable with temperature. Porapak behaves as good solid-food simulant even at high temperature. [ABSTRACT FROM AUTHOR]

The presence of toxic metals on paper pulp and the migration of these metals to food from the food package is receiving significant attention. The final exposure levels for consumers depend on two main processes. First the potential of metals to bind paper pulp during manufacture. Second, the metal potential to migrate from paper to food during storage and use.Binding and unbinding processes are modelled for cadmium kinetics through kinetic approaches.The cadmium concentration in paper pulp is estimated from the cadmium concentration in the water–pulp liquor during manufacture, the temperature, and contact time. Two food simulants have been employed for desorption studies, water and acetic solution (3%, w/w). As expected, under acidic conditions desorption is total and rapid (close to 100% desorption reached in a few minutes). However, the desorption of cadmium into the neutral food simulant depends on the initial cadmium concentration in the paper pulp, temperature and contact time. Surface response curves for each combination are presented.Temperature did not affect cadmium binding, but played a significant role for the desorption processes into the neutral food simulant.The proposed equations offer a good fitting of the experimental values, with p<0.001 and residuals within a factor of 3 for over 99% of the measured data. These models allow estimations of the expected exposure levels in consumers, on the basis of manufacture and use conditions. Linking the expected exposure with toxicity thresholds, such as the admissible daily intake (ADI), would allow a scientific assessment of the maximum acceptable cadmium levels in water–pulp liquors during manufacture and in the final paper pulp on the basic of the use patterns of each food packaging material. [Copyright &y& Elsevier]

In this work, a number of handsheets made from unbeaten and unbleached kraft, refiner mechanical and cotton linter pulps and crack propagations on paper samples under monotonic loading, were analyzed and possible links with the properties of fibrous networks were investigated. Crack initiation and propagation on the tested paper strips were also investigated under a scanning electron microscope to determine visually the state of the paper matrix under applied loads. Furthermore, paper samples were subjected to a series of mechanical tests, such as tearing resistance, folding endurance and tensile strength. The primary goal of this study concentrated on determining the fatigue life responses of paper samples under cyclic loading. An empirical equation for the fatigue life responses of paper samples tested was developed. It was found that paper, being a heterogeneous composite material, responds differently to applied loads depending on the properties of its constituent individual fibers and the nature of interfiber bonding in its structure. Kraft handsheets, for instance, showed the highest mechanical properties, followed by samples made from refiner mechanical pulps and cotton linters respectively. Overall, the equation developed proved to be a good way of predicting the fatigue life of paper materials subjected to variable loads. [ABSTRACT FROM AUTHOR]

Promoting the application of environmentally friendly packaging such as those made out of paper-pulp requires a basic understanding of the mechanical behaviour of paper-pulp (material) as well as that of packaging (product). In this paper, results from the investigation to determine the mechanical properties of paper-pulp packaging are presented. This includes the determination of tensile and compressive strength of paper-pulp packaging and also to find out whether this material exhibits high variation in the earlier properties. Experiments were conducted on paper-pulp packaging used for the packaging of video recorders. Specimen testing as well as testing of functional elements of packaging (rib separated from packaging support) is explored. In addition to the testing on real world paper-pulp packaging samples, FEM modelling and analysis is carried out using the rib similar to those used in testing. Based on this numerical modelling, effect of change in geometry of rib on its mechanical behaviour is explored. [Copyright &y& Elsevier]

Abstract: This paper identifies several drawbacks in the models of absorption and desorption of cadmium presented by [Garcia-Gomez, C., Carbonell, G., 2004. Modelling the absorption and desorption of cadmium on paper pulp using kinetic approaches. Chemosphere 55, 869–878]. It then provides suggestions on improving the effectiveness of the model. [Copyright &y& Elsevier]