Various macromolecular parameters of air-dried Agave sisalana (sisal) fibre are investigated by small-angle X-ray scattering (SAXS) techniques considering it as a densely packed micellar system by applying the theories put forward by Vonk (1973). The authors show that the small-angle X-ray scattering intensities of de-waxed air-dried sisal fibre deviate from Porod's law, establishing that the fibre is non-ideal two-phase structure characterized by continuous variation of electron density at the phase boundary. Therefore the mean square electron density gradient < mod grad eta mod 2> in isotropic structure is proportional to the fourth moment integral s4/(s) ds of the SAXS intensity distribution and to the second derivative of the correlation function at the origin in reciprocal space where s is the radial coordinate in reciprocal space. Since sisal fibre has a two-space structure with unsharp phase boundaries, the above relations are used to find out the thickness E of the transition region. The most general approach to the small-angle X-ray scattering makes use of the correlation functions, which were introduced by Debye and Bueche (1949) and which contain implicitly all the information obtainable from the scattering curve. The scattered intensities and correlation functions are related by Fourier transformations. Other important physical parameters are obtained with the help of one- and three-dimensional correlation functions are D, the average periodicity transverse to the layer, S/V, the specific inner surface phi 1, the volume fraction of matter, phi 2, the volume fraction of void lc, the length of coherence, l1 and l2, the transverse lengths, lr, the range of inhomogeneity, fc, the characteristic number and 2E/D, the volume fraction of transition layer.

ABSTRACT:Small Angle X-ray Scattering due to degummed ramie fibres were recorded using a Compact Kratky Camera, having counter device. The fibres were taken both in natural state and alkali treated state at room temperature. Various macromolecular parameters, such as D the average periodicity transverse to layer, S/ V, the specific inner surface, E, the width of transition layer, T,, T,_, T,, transversal lengths I, length of coherence etc. were calculated by using the correlation functions of the smeared out scattering curve of the different samples. Increase in the value of D with concentration of sodium hydroxide solution may be due to swelling of macromolecules present in the fibre. The calculation of various parameters were done by applying theories of Ruland 14 and Vonk. 7 KEY WORDS Small Angle/ Small Angle X-Ray Scattering/ Non-Ideal Two Phase System/ Correlation Functions / Periodicity Transverse to The Layer / Width of Transition Layer / Ramie is a natural cellulosic fibre. Being the longest and strongest fibre of vegetable origin, it has suitable textile uses. 1 It is often blended with cotton to improve its textile properties. 2 As Ramie is mostly cellulosic, it comes under the macromolecular system. We present here the SAXS studies on ramie fibres to compare the macromolecular structure of natural fibre with fibres treated in sodium hydroxide solution at different concentration.The work of Misra et al. 3 • 4 on natural cellulosic fibre like cotton, sisal etc. shows that natural cellulosic macromolecules possess non-ideal two phase structure. Ramie being a natural polymer, exists in a semicrystalline state. On analysing the scattering data of the samples it is revealed that, ramie fibre belongs to non-ideal two phase system. According to Porod 5 · 6 for an ideal two phase densely packed system, with sharply defined phase boundaries, the product 1(0)0 3 comes out to be constant at the tail end of sma11 angle X-ray scattering (SAXS) curve, here 1(0) is smeared out intensities and O is half the scattering angle. It has been shown by Vonk 7 that above product doesn't remain constant and decreases with 8, as electron density changes continuously over a certain region between the two phases (i.e., matter and void) known as width of transition layer E. EXPERIMENT ALRamie fibre was co11ected from Faculty of Textile Science and Technology, Shinshu University, Tokida, Japan. It is silky white in colour and lusturous in appearance: The fibre is least affected by moisture and highly resistant to bacteria and fungi. It is also very durable and can easily be bleached and dyed. Ramie can most satisfactorily be used for same purpose as cotton, flax and hemp. Natural Ramie fibre contains some gummy matter which is a heterogeneous mixture of carbohydrates of a complex chemical nature. 8 So the sample was degummed by the process reported by Roy. 9 As a result of this, gum was removed and the sample attains a hohlraum character.' 0 · 11 A part of the sample was soaked in sodium hydroxide solution at concentrations pH 11 a...

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