Natural Fibrous Materials Research Articles

Pengolahan Material Serat Alami Menggunakan Enzim Mikrobiologi untuk Media Ekspresi Seni Dua Dimensi

One of the alternative media, which is potential to be developed is the use of natural fiber materials from the environment (indigenous material). This natural fiber in foreign country such as Thailand, Japan, United States has crossed the threshold of the quality as a work of art that create by an artist. Meanwhile in Indonesia it is still brand new to be develop as a media of art expression. Indeed, art paper has already developed in Indonesia, but it is still a boundary production of pieces of paper that will be directly applied as a handicraft media. Moreover, the preparation process is still using the conventional method using chemical materials such as NaOH, Hypochloride, Boric acid, Chlorin, H 2 O 2 , etc., which burden the environment. Therefore an alternative, environmental friendly process is necessary to be developed to exploit natural fiber materials as a media of art expression. For this reason in this project a research on fiber-pulping process using xylanase enzyme has been carried out. The use of xylanase is enable to decrease chlorin consumption and reduce chloro-organic concentration in pulp and waste, that also means a reduction in production cost. The pulp was then used to make a paper to be tested for its quality by the Center for Pulp and Paper (Balai Besar Pulp dan Kertas, BBPK). This research resulted in a) enzyme formulations for the fiber-pulping and preparation from variety of fiber materials: banana’s stalk, the abacca, hyacinth, straw, pineapple fiber and gold cocoon, b) data of paper quality, and c) work of arts from fiber/pulp material. In conclusion, enzyme can be applied in fiber-pulping process for lower impact on the environment and the workers.

Lattice Boltzmann modeling of the effective thermal conductivity for fibrous materials

This paper presents a full set of numerical methods for predicting the effective thermal conductivity of natural fibrous materials accurately, which includes a random generation-growth method for generating micro morphology of natural fibrous materials based on existing statistical macroscopic geometrical characteristics and a highly efficient lattice Boltzmann algorithm for solving the energy transport equations through the fibrous material with the multiphase conjugate heat transfer effect considered. Using the present method, the effective thermal conductivity of random fibrous materials is analyzed for different parameters. The simulation results indicate that the fiber orientation angle limit will cause the material effective thermal conductivity to be anisotropic and a smaller orientation angle leads to a stronger anisotropy. The effective thermal conductivity of fibrous material increases with the fiber length and approach a stable value when the fiber tends to be infinite long. The effective thermal conductivity increases with the porosity of material at a super-linear rate and differs for different fiber location distribution functions.

Artificial and natural fiber fabrics with immobilized reagents in chemical test methods of analysis

Fabric matrices made of viscose and cotton fiber with adsorption-immobilized organic reagents are considered with respect to their possible use for chemical test methods of analysis. Triarylmethane, thiazine, eurhodine, acridine, azo, and diazo compounds are used for immobilization. It is found that the degree of reagent retention (R, %) depends on the pH and the type of the matrix used. R varies within 12–99%. The absorption spectra of the reagents immobilized on fabric matrices exhibit hypsochromic or bathochromic shifts of absorption bands (2–45 nm as compared to their absorption spectra in solution). As a rule, the degree of retention is higher for the reagents that exhibit a shift of the absorption band on the support. The adsorption isotherms of the reagents on various cellulose supports are analyzed. Test procedures are developed for the determination of antimony and mercury using modified fabric matrices. The rapidity, precision, and sensitivity of previously developed procedures for the test determination of Cu(II), Cd, and S2− are improved. The relative standard deviations of the determinations are no more than 0.1; the analysis time is 5–10 min.

Mechanical properties of short-flax-fibre reinforced compounds

The mechanical properties of flax/polypropylene compounds, manufactured both with a batch kneading and an extrusion process were determined and compared with the properties of Natural fibre Mat Thermoplastic (NMT) composites. The fibre length and width distributions of the fibres from the compounds were determined and used to model the expected properties of the materials, which led to reasonable predictions of the interfacial shear stress. It was found that, given their mechanical properties, flax fibres are quite effective in improving strength and stiffness of a compound and effective compatibilisation of the fibre/matrix interphase can be easily reached. The most important factor limiting the properties of the compounds lies in the intricate structure of the fibres themselves, after the interfacial strength is optimised, the internal fibre structure becomes the weakest point.

Plasma Treatment of Silk

Silk, as most of the natural textile fibres, shows many excellent qualities but also some defects. In particular natural fibres are in general delicate and cannot be treated under extreme conditions, for instance at high temperatures or in reactive solutions. This makes silk a very promising object for cold plasma treatment, which happens at room temperature in absence of solvents. A review of the different experimental results obtained at the research center PlasmaPrometeo on the surface modification of silk by various plasma processing will be presented.

Investigation of stochastic properties of the natural fiber mats

Natural fiber reinforced plastics are challenging materials for sustainable product development. Plastics reinforced with non-woven natural fiber mats can be applied in automotive structures due to good mechanical properties and low price. Hence, these materials have large properties variations (heterogeneity). The definition of properties of the heterogeneity was proposed. A method for quantitative estimation of heterogeneity of natural fiber mats has been developed. The method is based on spectral analysis of digital image of the mat. Estimated heterogeneity parameters of mats can be used further in simulation of properties of heterogeneous materials.

Porous carbon–carbon composite replicated from a natural fibre

Highly porous carbon composites, suitable to be used as electrodes in electrochemical double layer capacitors, could be produced by pyrolysis of resorcinol-formaldehyde resins impregnated onto a natural fibre material (celullosic fabric), without additional template agents or special drying of the polymer gels.

Evaluation of Pulps from Natural Fibrous Material for Use as Reinforcement in Cement Product

Low-cost natural fibers, available in developing countries, have been studied as replacements for asbestos in fiber cement materials. Laboratory pulps prepared from commercial sisal, by-product sisal, banana strands, and eucalypt kraft residue are compared to Pinus radiata kraft pulp, a reinforcement already widely used in commercial building materials. Fiber aspect ratio, percentage fines, freeness, and coarseness values of the various fiber pulps were measured in an attempt to correlate fiber properties to fiber performance when used as cement composite reinforcement. The effectiveness of mechanical treatments in generating superficial fibrillation of sisal and banana fibers in order to improve the mechanical bonding of these fibers to the matrix was confirmed by scanning electron microscopy. Unrefined Eucalyptus grandis fibers, residues from a kraft pulp mill, were observed to possess irregular shapes and surfaces that could give rise to an acceptable level of mechanical bonding to the matrix. This behavior, coupled with other morphological and physical properties, suggest these short fibers are adequate as reinforcement for cement.

On surface distributions in natural cellulosic fibres

AbstractIn x‐ray photoelectron spectroscopy (XPS), knowledge of elemental depth distributions within the first 10 nm is often essential. However, none of the conventional XPS methods can reliably discern, for example, a thin overlayer from clusters on rough surfaces. Therefore, reliable experimental data on the actual distributions of lignin and extractives on the fibre surfaces is needed, although there are numerous XPS studies on cellulosic fibres and paper.We have studied surface distributions of organic compounds on natural cellulosic fibre materials (cotton, flax and softwood pulps) with XPS, using a novel approach introduced by Tougaard. We were able to model the surface composition of rough fibre surfaces via simple spectral analysis of the O 1s signal. The simple spectral background analyses used show that in the case of cotton and flax, the non‐cellulosic compounds cover the cellulosic fibre surface much more effectively than in softwood pulps, in spite of the smaller amount of non‐cellulosic material present. Copyright © 2004 John Wiley & Sons, Ltd.

Infrared Microspectroscopic Mapping of Natural Textile Fibers

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.

Reproducible XPS on biopolymers: cellulose studies

AbstractThe development of ‘user‐friendly’ surface analytical instrumentation has expanded the application of x‐ray photoelectron spectroscopy (XPS) towards softer and more complex composite materials. However, the knowledge of fundamental phenomena in practical, interdisciplinary applications is dearly needed. In the case of polymers and polymer‐based or ‐reinforced composites, the analytical problems are not only related to detection limits and resolution; indeed, the effects of contamination and experimental artefacts on interpretation of the carbon signal are often the more crucial challenge.As a biopolymer, natural cellulose fibres provide an interesting model system for polymer studies. Numerous published XPS studies on lignocelluloses highlight both the possibilities and the problems of the surface analytical probes in analysis of air‐exposed organic materials.We report XPS experiments of cellulosic natural fibre materials, discussing the effects of sample storage, UHV exposure, radiation doses, charging and data analysis. Based on a large body of experimental data we also propose that clean paper specimens could be used as an in‐situ reference in polymer studies. Copyright © 2004 John Wiley & Sons, Ltd.

Permeability-Porosity Relationship in RTM for Different Fiberglass and Natural Reinforcements

This study investigates the permeability-porosity relationship for glass and natural fiber mats. The estimation of the permeability-porosity relationship for glass mats is not new and has been investigated before by several authors, but in the present paper the same relationship was discovered for natural fibers. The experimental permeability values were fitted by the Carman-Kozeny equation with two fitting parameters: the Kozeny constant and the exponent of the porosity. The obtained permeability for the natural fiber mats shows higher values than glass fiber mat.

Bioremediation of methyl tertiary-butyl ether (MTBE) by an innovative biofilter

Methyl tertiary-butyl ether (MTBE) is a synthetic chemical used in unleaded gasoline as an additive to reduce levels of ozone and carbon monoxide from auto exhaust. Due to its chemical and recalcitrant properties, MTBE has caused groundwater contamination worldwide. A laboratory-scale biofilter made of a natural fiber (kenaf) mat and inoculated with MTBE-degrading microorganisms, was evaluated for MTBE removal efficiency. Operational parameters of oxygen flow rate, hydraulic retention time (HRT), yeast extract and initial MTBE concentration were varied and MTBE removal efficiencies determined. Four kinetic models were evaluated to describe the MTBE removal in the reactor. Formaldehyde and tertiary butyl alcohol (the most two reported MTBE biodegradation byproducts) were not found in the effluent; instead, carbon dioxide was monitored as the end product based on the results of a metabolic mass balance evaluation. Toxicity of treated effluent was evaluated by employing the Microtox acute toxicity test and comparing that to the influent.

World Production of Textile Raw Materials in 2002

Production of all types of chemical and natural textile fibres increased by 4.2% in 2002 in comparison to the previous year and attained 62.7 million tons. World production of chemical fibres increased by 6.1% in 2002, to 36.5 million tons, including a 6.2% increase for synthetic fibres, to 33.8 million tons, and a 1.6% increase in cellulose fibres (for the first time in recent years) by 1.6%, to 2.7 million tons. Polyester fibres and yarn remained the leaders in world production of textile raw materials, of which 81% was concentrated in Asia and half of the production volume was in China and Taiwan.

Evaluation of Pulps from Natural Fibrous Material for Use as Reinforcement in Cement Product

Abstract Low-cost natural fibers, available in developing countries, have been studied as replacements for asbestos in fiber cement materials. Laboratory pulps prepared from commercial sisal, by-product sisal, banana strands, and eucalypt kraft residue are compared to Pinus radiata kraft pulp, a reinforcement already widely used in commercial building materials. Fiber aspect ratio, percentage fines, freeness, and coarseness values of the various fiber pulps were measured in an attempt to correlate fiber properties to fiber performance when used as cement composite reinforcement. The effectiveness of mechanical treatments in generating superficial fibrillation of sisal and banana fibers in order to improve the mechanical bonding of these fibers to the matrix was confirmed by scanning electron microscopy. Unrefined Eucalyptus grandis fibers, residues from a kraft pulp mill, were observed to possess irregular shapes and surfaces that could give rise to an acceptable level of mechanical bonding to the matrix. This behavior, coupled with other morphological and physical properties, suggest these short fibers are adequate as reinforcement for cement.

Natural fiber composites with plant oil-based resin

Vacuum-assisted resin transfer molding or resin vacuum infusion process was used to make composite panels out of plant oil-based resin [acrylated epoxidized soybean oil (AESO)] and natural fiber mats made of flax, cellulose, pulp and hemp. The composites formed by room temperature cure with natural fiber reinforcement of about 10–50 wt% increased the flexural modulus to a range between 1.5 and 6 GPa depending on the nature of the fiber mat. The AESO resin reinforced with woven E-glass fiber was tested as a reference and gave a flexural modulus of 17 GPa, while a room temperature curing of the neat resin gave a flexural modulus of about 1.1 GPa. Recycled paper was used as a cheap resource of cellulose fiber and found to work well with AESO resin in terms of flow, impregnation, and surface bonding, giving a modulus of over five times that of the neat resin. These low-cost natural composites were found to have mechanical strength and properties suitable for applications in housing construction materials, furniture and automotive parts.

Sheet‐Molded Polyolefin Natural Fiber Composites for Automotive Applications

AbstractThe use of natural fibers as reinforcing filler in thermoplastics is a relatively new application and has great potential in replacing glass fiber products in automotive industry. However, most of the research in this area has been focused primarily on flax fiber. In the first part of the work presented here, hemp fiber non‐woven mats are used exclusively in combination with a poly(propylene) matrix to study the mechanical properties of natural fiber mat thermoplastics (NMT) in the absence of binder. Film stacking was used as the method of preparation. The results show that hemp‐based NMT have comparable or even higher strength properties as compared with conventional flax‐based thermoplastics. A value of 63 MPa for the flexural strength is achieved at a fiber content of 64 wt.‐%. The influence of the compression ratio on the mechanical properties and density of NMT is also reported. A definite increase in strength is observed with increasing compression together with a much more uniform density profile. In the second part of this study, a unique combination of random hemp fibers, non‐woven mats and poly(propylene) films was employed in film stacking to evaluate strength properties and economic implications. The same fiber content (64 wt.‐%) was maintained in the final NMT by replacing 78 wt.‐% of the mats by random fibers. Preliminary tests reveal better mechanical properties especially in terms of impact energy, which is 50 to 100% higher, as compared with different mats‐only/poly(propylene) combinations. Further, a net saving of 40% in fiber cost is anticipated by replacing 78% non‐woven mats with an equivalent amount of random fibers. Overall results of this study indicate that hemp‐based NMT are promising candidates in automotive applications where high specific stiffness is required.Tensile Strength of different NMTs and GMT.magnified imageTensile Strength of different NMTs and GMT.

Carbon storage potential in natural fiber composites

The environmental performance of hemp based natural fiber mat thermoplastic (NMT) has been evaluated in this study by quantifying carbon storage potential and CO 2 emissions and comparing the results with commercially available glass fiber composites. Non-woven mats of hemp fiber and polypropylene matrix were used to make NMT samples by film-stacking method without using any binder aid. The results showed that hemp based NMT have compatible or even better strength properties as compared to conventional flax based thermoplastics. A value of 63 MPa for flexural strength is achieved at 64% fiber content by weight. Similarly, impact energy values (84–154 J/m) are also promising. The carbon sequestration and storage by hemp crop through photosynthesis is estimated by quantifying dry biomass of fibers based on one metric ton of NMT. A value of 325 kg carbon per metric ton of hemp based composite is estimated which can be stored by the product during its useful life. An extra 22% carbon storage can be achieved by increasing the compression ratio by 13% while maintaining same flexural strength. Further, net carbon sequestration by industrial hemp crop is estimated as 0.67 ton/h/year, which is compatible to all USA urban trees and very close to naturally, regenerated forests. A comparative life cycle analysis focused on non-renewable energy consumption of natural and glass fiber composites shows that a net saving of 50 000 MJ (∼3 ton CO 2 emissions) per ton of thermoplastic can be achieved by replacing 30% glass fiber reinforcement with 65% hemp fiber. It is further estimated that 3.07 million ton CO 2 emissions (4.3% of total USA industrial emissions) and 1.19 million m 3 crude oil (1.0% of total Canadian oil consumption) can be saved by substituting 50% fiber glass plastics with natural fiber composites in North American auto applications. However, to compete with glass fiber effectively, further research is needed to improve natural fiber processing, interfacial bonding and control moisture sensitivity in longer run.

Comparison between KES-FB and FAST in Discrimination of Fabric Characteristics

In order to provide a basis for parameter setting during the process of making man-made fiber fabrics as imitations of natural fibers fabrics, to understand characteris tics of natural fiber fabrics and to establish discriminant methods for such characteristics have become important subjects in the textile industry nowadays. By applying discriminant analysis and neural network, I have successfully used fabric physical properties measured by KES-FB system and FAST system to establish discriminant models for fabric characteristics of cotton, linen, wool and silk. KES-FB discriminant model that applied fabric mechanical properties appeared to have a better classification ability than FAST discriminant model. On the other hand, the discriminant model established by applying neural network appeared to have a better classification ability than that by applying discriminant analysis. While only 9 and 5 physical properties of fabrics measured by KES-FB system and FAST system, respectively, needed to be applied, the discriminant model established by applying stepwise method should possess the characteristics of simplicity, convenience and effectiveness.

Acoustic emission studies on the lubrication of a fibrous collagen material-leather

For thousands of years, collagen materials, such as leather, have been among the most dominant natural fibrous materials used by humans. Fatliquoring is one of the critical steps in the leather-making process, wherein oil or a lubricant is added to the leather to prevent the leather fibers from sticking together, thereby providing sufficient pliability to the leather. We have examined the feasibility of using the acoustic emission (AE) technique to characterize the degree of lubrication of leather produced with various fatliquor concentrations. In a tensile test, an acoustic transducer was contacted with the leather samples to collect their AE quantities and properties. The samples lubricated with a fatliquor concentration less than 10% showed twin peaks on the plot of hits rate versus time. This implied that a non-uniform fracture occurred in a leather structure that was not sufficiently lubricated. In contrast, a sufficiently lubricated leather structure showed a steady increase in hits rate with time until it fractured. Traditional stress-strain tests did not reflect these behaviors. Observations also showed a direct correlation between the cumulative hits and fatliquor concentration. The results of this work may provide a route to identify an adequate degree of lubrication in the leather.