Green fibres

Heiber, J. Clemens, F. Graule, T. Hiilsenberg, D., Thermoplastic extrusion to highly-loaded thin green fibres containing Pb(Zr,Ti)03 , Advanced Engineering Materials 7 [5] 2005,404-408... 

The properties of NR eomposites are eontrolled by natural fibre eontent, natural fibre orientation and adhesion between green fibre and NR matrix." The mechanieal property of the polymer eomposite increased. The modulus and hardness and oil resistanee of the resulting NR increased with inereasing tea leave waste but the tensile strength and elongation at break of the NR compound decreased as a function of tea leave waste. In addition, the NR compound with tea leave and carbon black exhibits excellenee in thermal properties. The polymer composite possesses the best properties at 30 phr of modified tea leave with MMA and 30 phr of carbon black. 

It is a much simpler and more cost-effective alternative to separate the bast fibre from the plant straw [26]. The raw material for this procedure is either field dried or slightly retted plant straw. The bast fibres are separated from the woody part by mechanical means. Weather-dependent variations of fibre quality are eliminated. However, the produced green fibres are much coarser and less fine as compared to dew or water retted fibres. 

Green fibres like flax, jute, sisal, kenaf and fibres of allied plants, which have been used for more than 8000 years, are the present and will be the future raw materials not only for the textile industry but also for modern eco-friendly composites used in different areas of application like building materials, particle boards, insulation boards, food, fodder and nourishment, friendly cosmetics, medicine and source for other bio-polymers agro-fine chemicals and energy . Potentially, under optimum cultivation conditions, they cause little or no detrimental effect on the ecosystem, they can grow in different climatic zones and they recycle the carbon dioxide in the Earth s atmosphere. 

Green fibres/bast fibrous plants will also be used in growing quantity in 36... 

The ciurent lack of a common definition for eco, sustainable, and green fibres makes it difficult for organizations to make informed fibre choices. In accordance with their company objectives, organizations will need to determine and define what goals and parameters to set arormd their choice of sustainable fibres. 

Kenaf/ Mesta / Hibiscus/ Rosella is a hemp-like member of the hibiscus family. The cellulose of Kenaf is extracted for the production of green fibres. It is known to be one of the greenest alternatives to [paper] making and has large commercial applicability. There is evidence that Kenaf was domesticated as far back as 5000 BC in Egypt. 

The yellow-green fibres were very coarse, and microscopy revealed that they had an unusual delta-wing cross-sectional appearance with two long lobes and one short one (Figure 2.1). The thickness indicated that they may have originated from a rug or carpet and that tracing their source could be possible. 

On 24 May 1981, the nude body of Nathaniel Cater was pulled from the Chattahoochee River approximately one mile downstream from the James Jackson Bridge in Northwest Atlanta. Yellow-green fibres were found in his hair. Two days earlier Wayne Williams had been seen driving across this bridge, and he became a possible suspect in the murder case. 

The spectrophotometric analysis confirmed that the dyes used in the control fibres, removed from the carpet found in the home of Wayne Williams, and in the yellow-green fibres removed from the hair of Cater, were identical (Figure 2.2). 

Emphasis is also being given to on green or eco polymer additives, such as sorbitol, vitamin E, natural fibres, etc. [32,73,74],... 

The fabrication and characterization of a fiber optic pH sensor based on evanescent wave absorption was presented by Lee63. The unclad portion of a multi-mode optical fibre was coated with the sol-gel doped with pH sensitive dye. The sensitivity of the device increased when the multiple sol-gel coatings were used in the sensing region. The dynamic range and the temporal response of the sensor were investigated for two different dyes -bromocresol purple and bromocresol green. 

Numerous linear diamines, such as many of those in the survey mentioned above, have been evaluated as potential replacements for benzidine, an inexpensive and highly versatile intermediate that was banned in the 1970s because it posed a carcinogenic threat. Two trisazo dyes have been synthesised recently using 4,4, diaminodiphenyl thioether instead of the benzidine component of Cl Direct Black 38 (3.112 X = Y = NH2) and Cl Direct Green 1 (3.112 X = OH, Y = H). These new dyes exhibited higher substantivity and fastness to washing than the two traditional products on cellulosic fibres [119]. 

Bindschedler s Green (6.204) can be made by condensing p-nitroso-N,N-dimethylaniline with N,N- dimethyl aniline. A similar condensation with 2-naphthol gives Meldola s Blue (6.209 Cl Basic Blue 6), the first oxazine dye, discovered in 1879. The symmetrical Cl Basic Blue 3 (6.210) is of more commercial significance. It is synthesised by nitrosation of N,N-diethybrn-anisidine followed by condensation with N,N-diethybm-aminophenol, and is used for dyeing acrylic fibres. This dye is now classified by ETAD as toxic [73]. 

Aniline black is also an important fast dye for cotton and is produced on the fibre at a high temperature (by steaming ) from an aniline salt (hydrochloride) and an oxidising agent. It is not probable that the two kinds of this dye which are known have the same constitution, for they have different degrees of stability towards acid technical aniline black probably contains phenazine ring systems (Bucherer, Green). 

---