Green Nanocomposites Made With Polyvinyl Alcohol and Cellulose Nanofibers Isolated From Recycled Paper

This paper reports green nanocomposites made by blending polyvinyl alcohol(PVA)with cellulose nanofiber(CNF)isolated from recycled deinked copy/printing paper(DIP).The reinforcement effect of DIPCNF in the nanocomposites is compared with other CNFs isolated from native cotton and hardwood by means of TEMPO-oxidation.The prepared PVA-CNF nanocomposites are characterized in terms of morphology,chemical interaction,structural,thermal and mechanical properties.X-ray diffraction and Fourier transform infrared spectroscopy confirm the reinforcing ability of cellulose nanofibers into PVA.By blending CNFs into PVA matrix,the thermal stability of the nanocomposites is improved and DIPCNF shows similar enhancement effect with COCNF and HWCNF.The prepared nanocomposites exhibit 50%Young’s modulus improvement by adding 6%of CNF and DIPCNF exhibits similar enhancement of the mechanical properties to COCNF and HWCNF in the nanocomposites.This indicates that the use of DIPCNF is beneficial for environment protection,resource retaining and save energy in comparison with COCNF and HWCNF.

Transparent and semi-interpenetrating network P(vinyl alcohol)-P(Acrylic acid)hydrogels:pH responsive and electroactive application

In this paper,poly(vinyl alcohol)-poly(acrylic acid)based transparent semi-interpenetrating network(semi-IPN)hydrogels were synthesized by using a solvent mixture of dimethyl sulfoxide and deionized water via free radical polymerization and subsequent freeze-thaw technique.The formation of the semi-IPN hydrogels was conformed from FT-IR spectra.The acrylic acid concentration effect on the hydrogels was investigated in terms of transparency,crystalline structure and thermal stability by using UV-visible spectroscopy,X-ray diffraction and thermogravimetric analysis.Swelling behaviours of the semi-IPNPAP hydrogels were studied in deionized water and different pH solutions.The compression and electroactive behaviour was tested in fully hydrated stage by using compression test and by applying electrical voltage.The hydrogels showed displacements under the applying voltage and detailed experiment is illustrated.