Showing papers on "Natural fiber published in 1987"

Cohesive finishes for composite materials

Abstract: An overlay of sheet material that is impregnated with thermosetting resin--typically a fabric of a type including metallic, synthetic fiber, natural fiber and ceramic cloths impregnated with epoxy resin--is wrapped about or laid on an underlay of material that is also impregnated with thermosetting resin--typically a resin material reinforced with fibers of the graphite, glass, aramid, or ceramic types. The overlay and underlay are cured under heat and pressure in an oven at the same time, causing cohesive bonding of the resin within each. The resin exudes through the fabric overlay during curing and forms a hard transparent shell of cured resin to the composite article. The embedded sheet material selectively imparts color, pattern, texture, reflectivity, penetration resistance, tensile strength, thermal and electrical conductivity, and other visual and mechanical properties to the composite article as desired. Exemplary configurations include lustrous metallic-coated cloths upon the surfaces of graphite golf club shafts or vaulting poles or sailboat masts, and electrically conductive cloths conducting electricity upon the surfaces of fiber-reinforced aircraft panels.

Thin-metal-wire conjugated yarn

Abstract: Thin-metal-wire conjugated yarn excellent in suitability for clothing and having EMI shielding which comprises a core composed of a thin metal wire having a diameter of 50μ or less and a chemical or synthetic fiber or natural fiber yarn, and another chemical or synthetic fiber or natural fiber yarn as sheath wound round and coated on said core, characterized in that the coating percentage is 70% or more based on the surface area of the conjugated yarn.

Preparation and some properties of variously deacetylated chitin fibers

Abstract: Variously deacetylated chitin (DAC) fibers were prepared by several coagulant systems, such as CuSO4-NH4OH, alcoholic sodium hydroxide and CuSO4-H2SO4. These fibers were found to have similar tensile properties independent of the spinning conditions. But the higher degree of protein immobilization was observed for DAC fiber prepared from CuSO4-NH4OH coagulant than those by other systems. The tensile properties of DAC fibers, especially wet properties and knot strength, were improved remarkably comparing with those of chitin and alkyl-chitin fibers.

The viscoelastic properties of wool and the influence of some specific plasticizers

Abstract: The relaxation behaviour of Lincoln wool fibres in water and in three short chain aliphatic alcohols was measured. Applying a two phase model including a relaxation function based on a log-normal distribution of relaxation times a good systematic description of the data was found. The application of the model to the relaxation curves of wool fibers in the alcoholic media showed the invariance of the shape of the relaxation function, its shift on the log-time scale and the change of the elastical properties of the morphological components of the wool fibre depending on the aliphatic chain length of the alcohols. The importance of the apolar interactions for the elastic and viscoelastic properties of the morphological phases in the wool fibre is discussed.

Knit composite vibration damper

Abstract: PURPOSE:To obtain the titled vibration damper containing a knit base material in a viscoelastic layer, having excellent shape-retaining abilities under heating and outer force-adding conditions as well as low temperature dependence and frequency dependence of vibration-damping properties and suitable in automobile, railway rolling stock, marine, industrial machine, etc. CONSTITUTION:The aimed vibration damping containing (B) a knit base material consisting of animal or vegetable fiber, natural fiber, regenerated fiber, synthetic fiber, glass fiber, carbon fiber, etc. and having >=5% (preferably >=20%) elongation of fiber in (A) viscoelastic layer consisting of asphalt, vinyl chloride, epoxy, urethane, unsaturated polyester, silicone resin, etc. Further more, the above- mentioned vibration damping is produced e.g. by impregnating the component A (directly as liquid raw material in case of thermosetting resin and an (semi) liquid obtained by heating or dissolving in a solvent in case of thermoplastic resin) to the component B and molding the impregnation. other uses of the vibration damping include building and construction related material, electrical appliance, sport, leisure goods.

Production of nonwoven fabric having excellent elasticity

Abstract: PURPOSE:To obtain a nonwoven fabric having good formability and excellent elasticity, by compounding a specific aqueous resin emulsion with a specific amount of hydraulic cement, applying the resultant composition to a nonwoven fabric mat and heating the product. CONSTITUTION:A nonwoven fabric mat is produced by needling a fiber mat composed of 15-50wt% fiber binder having a melting point of 110-200 deg.C such as polypropylene as a thermoplastic resin fiber binder and 85-50wt% synthetic or natural fiber having higher melting point than the binder by >=40 deg.C. The obtained fabric mat is coated with a coating composition obtained by compounding (A) 100pts.wt. (in terms of solid resin content) of an aqueous emulsion of a resin having a glass transition point of <=20 deg.C, (B) 50-400pts.wt. of a hydraulic cement, (C) 0-25wt% colorant based on the component B and (D) 0-350pts.wt. of a non-hydraulic inorganic powder, wherein the sum of B+C+D is <=400pts.wt. per 100pts.wt of the component A. The amount of the coating composition is 15-300wt% based on the mat in terms of solid content. The objective nonwoven fabric having excellent elasticity can be produced by thermally drying the coated mat, thereby removing water from the composition.

Manufacture of laying material having rigidity

Abstract: PURPOSE:To manufacture a laying material having a rigidity by a method wherein needle punch is applied on a laminate, in which expandable thermoplastic resin particles are pinched between nonwoven fabrics, to entangle upper and lower layers, thereafter, resin water-based emulsion is impregnated by coating and the coated surface of the laminate is heated to expand the thermoplastic resin particles and dry the resin water-based emulsion. CONSTITUTION:The nonwoven fabric of needle punch nonwoven laminate consists of 15-50wt% of resin fiber binder having melting point of 80-180 deg.C and 85$50wt% of resin fiber having a melting point higher than the same of said fiber binder by 40 deg.C or more or natural fiber while expandable polystyrene particle having the grain size of 1.5mm or less is utilized as expandable thermoplastic resin particle. 10-200pts.wt. of the expandable thermoplastic resin particles are used with respect to the 100pts.wt. of the nonwoven fabric while the water-based emulsion of resin is spread on the nonwoven fabric by the rate of 30-1,000g/m in the weight of solid resin. The coated surface is dried by hot air in order to effect the prevention of the deterioration of the fibers and the foaming of the plastics sufficiently.

Characterization of the Rheological Response of a Class of Single Fibers

Abstract: The rheological response of a class of single fibers of natural origin is considered from a phenomenological point of view on the basis of the well‐known super‐position principle in viscoelasticity. A rheological model is presented which aims at the determination of both the creep and relaxation functions over the considered range of applied stress, or strain, and the extent of time covered. The proposed model is illustrated numerically for the case of the first creep of dry summerwood fibers of a longleaf pine holocellulose pulp and for the stress relaxation of cotton fibers. The model is presented in a general form and could be applied to a large class of viscoelastic materials.

X‐ray investigations of wool after chemical treatment

Abstract: Traitement de fibres de mohair avec des agents de surface, de l'acide nitrique ou de l'acide sulfurique; influence sur la structure supramoleculaire

Precision filter paper

Abstract: PURPOSE:To obtain the title filter paper capable of excellently retaining the fine particles in a liq. by forming a specified fiber mixture into a sheet. CONSTITUTION:The mixture of 5-50wt.% org. synthetic fiber consisting of a stiff straight-chain synthetic polymer, namely a polymer maintaining lineality in a solvent and having >=50Angstrom chain length (continuity length), and having <=0.7mum fiber diameter and 5-95wt.% fiber consisting of natural fiber and a synthetic polymer or inorg. fiber such as asbestos and having iota2mum diameter is formed into sheet to obtain filter paper. The microfibrillar fiber of an org. stiff straight-chain polymer is most perferably used as the fiber having <=0.7mum diameter, inorg. fiber or an org. stiff straight-chain polymer is used as the fiber having iota2mum diameter, and the mixture is formed into a sheet without using a binder. Since the obtained filter paper has high resistance of chemicals and heat resistance as well, the filter paper can be utilized for various purposes.

Effect of structural changes on the surface characteristics of regenerated and graft copolymerized silk fibroin films

Abstract: Silk fibroin (SF) and polyacrylic acid (PAA)-grafted silk fibroin were dissolved in calcium chloride/ethanol/water mixture (1/2/8 in mole ratio) at 70°C for 4 hrs. The dissolved silk fibroin and SF-g-PAA polymer were regenerated by casting the dialyzed solutions into the films, respectively. The freshly prepared silk fibroin film was soluble in water and mainly consisted of random coil structure. By treating with aqueous solutions of organic solvents, such as formic acid, trichloroacetic acid, and methanol, the silk fibroin was denatured into insoluble β-pleated sheet structure. The contact angles of silk fibroin and SF-g-PAA films were measured after treating the films with aqueous methanol solution. The surface tensions of the films were calculated in three dimensions consisting of dispersion, polar, and hydrogen bond components from the contact angle data by using determinant method. As IR crystallinity indices of silk fibroin films treated with solvents increased, the total surface tension, polar, and especially, hydrogen bond components increased linearly. However, the dispersion component was nearly independent of the IR crystallinity index of the film. On the other hand, in SF-g-PAA film, with increasing graft yield the total surface tension, polar and hydrogen bond components increased and the dispersion component decreased.

Manufacture or laminated sheet

Abstract: PURPOSE:To manufacture a laminated sheet superior in moisture resistance, by performing laminate molding of necessary sheets of resin impregnated bases under decompression by piling up then with a metal foil mounted on the top and/or the bottom of the same as required CONSTITUTION:Resin of a resin impregnated base, is thermosetting and thermoplastic resin in a single or, mixed or a denatured form of phenolic resin or cresol resin, for which the thermosetting resin especially the phenolic resin is used The base is woven cloth or nonwoven cloth or paper composed of an inorganic fiber such as glass or asbestos, or an organic synthetic fiber such as polyester resin or polyamide resin, or a natural fiber such as cotton, or a combination base of those and the paper base which is superior in bland processing properties and apt to have bubbles built-in is used desirably As a metallic foil, a single form of copper or nickel or an alloy of them is used as required As a degree of decomporession at the time of laminate molding is made desirably less than 100Torrs With this construction, a laminated sheet whose water absorbing rate is low is obtained