PREPARATION OF CHITIN NANOFIBERS-GOLD METALLIC NANOCOMPOSITE BY PHASE TRANSFER METHOD.

Chitin nanofibers (CNFs)- nanoparticles ( NPs) blends in dispersion, flakes and thin film or sheet forms were first prepared by mixing pre-organized NPs prepared in triblock copolymer with diluted CNFs suspension. Water soluble polymer triblock copolymer poly (methyl vinyl ether, PMVE) in the amount 0.6 wt.% was used to prepare NPs and 0.12 wt.% net chitin content was used as CNFs suspension to prepare the blended composite. NPs of size 4.4 nm (σ = 1.2) were obtained when salt ( (hydrogen tetrachloroaurate (III) trihydrate) was reduced by 5 equivalents of . PMVE polymer acted as a stabilizing or capping agent for pre-organized NPs. Completion of reaction was fast, all salt reduced to metallic form in just 15 min after the addition of . CNFs (1 wt.% chitin) which was used to prepare CNFs- NPs blend composite were prepared from crab shell in never dried acidic condition by established combination of chemical and mechanical processes that gave 25-40 nm width and high aspect ratio CNFs. When polymer capped NPs mixed with CNF suspension, all NPs and 56% polymer were mass transferred from water phase to entangle with more polar moieties of CNFs-water suspension as no trace of NPs were noticed in water-polymer mother liquor after blending with CNFs suspension. Particles size of CNFs- NPs composite was measured by employing TEM, SAXS and SEM techniques. CNFs- NPs composite were characterized in solution and compressed dried sheet form by recording digital images, UV-vis and XRD spectroscopies. CNFs- NPs suspension had antibacterial activity against gram positive bacteria S. aureus. [ABSTRACT FROM AUTHOR]