Investigation of Dielectric and Mechanical Properties of Pretreated Natural Sunn Hemp Fiber-Reinforced Composite in Correlation with Macromolecular Structure of the Fiber

The present study attempts to establish a correlation between the macromolecular parameters obtained from small angle X-ray scattering (SAXS) analysis of pretreated sunn hemp (Crotalaria juncea) fibers with the dielectric and mechanical properties of their composites. Sunn hemp fiber is pretreated chemically by dewaxing and alkalization methods and physically by microwave irradiation. The treatment effect is structurally investigated using a correlation function from SAXS data and correlated with the mechanical as well as electrical properties of composites. The macromolecular parameters are observed to be influenced by pretreatment methods. Macromolecular structural modifications are seen in dewaxed fiber (DSHC), fiber treated with 10% of alkali soaked for 6 h (10K6C), and fiber microwave irradiated with 800 watts for 6 min (800W6M), improving the mechanical as well as electric properties of the reinforced composites.

Study of enzymatic digestion of cellulose by small angle neutron scattering

Small angle neutron scattering (SANS) was used to study the structure of Avicel (FD100) microcrystalline cellulose during enzymatic digestion. Digestions were performed in either of two modes: a static, quiescent mode or a dynamic mode using a stirred suspension recycled through a flow cell. The scattering pattern for as-received Avicel in D(2)O buffer is comprised of a low Q power law region resulting from the surface fractal character of the microcrystalline fibers and a high Q roll-off due to scattering from water-filled nanopores with radii approximately 20 A. For digestions in the dynamic mode the high Q roll-off decreased in magnitude within approximately 1 h after addition of enzymes, whereas in the static digestions no change was observed in the high Q roll-off, even after 60 h. These results indicate that only with significant agitation does enzyme digestion affect the structure of the nanopores.