Ball-milling Promoted Chemical Bonding between Cellulose and Plastics - Ball Milling Towards Green Synthesis: Applications, Projects, Challenges - page 218

9.3.2 Characteristics of Micro-pulverized Cellulose
Ball milling of native cellulose, with a water content of less than 0.1 wt%,
produces fine powders of amorphous cellulose. Resultant cellulose powders
are so reactive that they exhibit unique properties due to the collapse of a
network of hydrogen bonding in a phase of cellulose I. Here two charac-
teristics are described: one is a crystalline transformation into cellulose II, 22
the other promoted aggregation of cellulose particles. 23
Amorphous cellulose powders, which are prepared by ball milling in
advance, are further ball-milled with a certain amount of water added, for a
fixed time; the product is denoted by MC w t , where the subscript and
superscript are relevant to the amount of water added (wt%) and the milling
time of cellulose with water added (h). Figure 9.11 shows X-ray diffraction
patterns of products as well as original cellulose. The products with r 30 wt%
water content are powdery, while those with 50 wt% are somewhat viscous.
Original cellulose is in phase I, with signals at 14.81, 16.81, and 22.61
assigned to the reflections (1,-1,0), (1,1,0), and (2,0,0), respectively. Notably,
MC 30 2h and MC 50 2h both have new signals at 12.11, 19.81, and 22.01,

500 cps

*

*

MC 50 2h

MC 30 2h

MC 10 2h

MC 0 2h

Original
cellulose

1k cps

10 15 20 25 30

2 q (degree)

Figure 9.11 X-Ray diffraction patterns of original CF11 (cellulose I) and samples
milled for 2 h with controlled amounts of water added (0, 10, 30, and
50 wt%, from bottom to top). The peaks marked with (*) are attributed
to contaminants from the milling pot and balls loaded in it.
Reprinted from ref. 22 with permission of Springer Science and Busi-
ness Media.