่2. Experimental
Materials: Microcrystalline cellulose, with average powder size
of 50 mm was supplied by Sigma, Germany. ENR (50% epoxy
degree) was supplied by Malaysian Rubber Board. Other reagents
supplied by sigma, Germany were used as received.
Films preparation: A pre-weighed amount of cellulose was
added to BMIMCl, heated to 90 1C and mechanically stirred for
3 h before ENR addition. The concentration of cellulose in BMIMCl
solution was 6 wt%. ENR was dissolved in THF and mechanically
stirred at 40 1C until the ENR was uniformly dissolved in the
solvent. ENR/THF solution then mixed with cellulose/ionic liquid
solution and stirred for 24 h at 85 1C. After THF extraction, the
homogenous viscous solution was casted on a plain glass plate and
immersed in distilled water to remove BMIMCl from the blends.
The prepared films were washed several times with deionised
water and dried at 80 1C for 3 h. Blends samples with compositions of 90/10, 80/20, 70/30 and 60/40 cellulose/ENR in wt% were
prepared and designated as RC/ENR-1, RC/ENR-2, RC/ENR-3 and
RC/ENR-4 respectively.
Characterization: FTIR spectra were recorded by a Perkin-Elmer
180 with resolution of 4 cm1 for 32 scans over a wave number
range of 4000–400 cm1. X-ray diffraction measurements were
performed on XRD diffractometer (Rigaku Miniflex II) in the 2θ
range of 3–70 using Cu Ka radiation. The crystallinity χc (%) of
cellulose blend films were obtained from the X-ray empirical
method proposed by Segal et al. [8].
χc ð%Þ ¼ IMaxIAm
IMax 100 ð1Þ
where IMax is the intensity at (200) peak, and IAm is the intensity at
the minimum between (110) and (200) peak.
FESEM was performed on the cryo-fractured samples were
frozen in liquid nitrogen using a JEOL JSM-6701F. The fractured
surface of the films was coated with gold prior to analysis. Thermal
analysis of the nanocomposite films was measured using PerkinElmer TGA 7 (Perkin-Elmer Instruments, USA). The temperature