Discipline:
Subcategory: Materials Science
Myles Everett - Georgia Institute of Technology
Commercial interest in nanocellulose is expanding quickly. Kim Nelson’s article, Chemical-free pulping with Green Box nanocellulose for light weight packaging, goes into depth about the profitability of nanocellulose retention for Green Box technology with a market potential of 3.7 million tons per year. The technology is used in products such as cosmetic skincare, lightweight plastic packaging, and concrete. There is belief by scholars that Nanocellulose fibers can increase the strength and absorbance of Kraft fiber. Effects on physical properties of adding nanocellulose as a composite material to Kraft pulp are unknown. In this experiment, cellulose nano crystals (CNC) and cellulose nanofibrillated (CNF), were tested as a composite material in refined bleached softwood. Five types of pulp were used in experimentation: a control group of refined softwood, 1 wt% CNC in refined softwood, 2 wt% CNC in refined softwood, 1 wt% CNF in refined softwood, and 2 wt% CNF in refined softwood. Pulp was refined and three sets of 10 hand sheets were made for each test group. Physical properties were tested to measure quantitatively the effect of CNC and CNF as an additive. Properties tested included freeness, grammage, thickness, brightness, tensile strength, tensile energy absorption (TEA), burst strength, and tearing resistance. During hand sheet formation, the CNF groups had a significantly lower freeness result than other groups. The control pulp, CNF 1%, and CNF 2% had a freeness of 412, 383, and 346 mL, respectively. Grammage, thickness, and brightness of each of the hand sheet groups was found to be statistically consistent across the five test group. The strength parameters did show more variation amongst test groups, but with a 95% confidence interval. More tests are being performed using a larger amount of retention aid as well as using a higher composition of nanocellulose in the hand sheets to further differentiate the test groups. Further tests to be done include 3 wt% CNC in refined softwood, 4 wt% CNC in refined softwood, 3 wt% CNF in refined softwood, and 4 wt% CNF in refined softwood. The level to which the nanomaterial is retained in the hand sheet will be tested. More emphasis will be placed on CNF than CNC after learning that CNC is not retained as well in hand sheets.
Funder Acknowledgement(s): UG Foundation
Faculty Advisor: Chris Luettgen, Chris.luettgen@rbi.gatech.edu
Role: The part of the research I did consisted of practicing methods of preparing hand sheets and testing properties. Developing a design strategy for how I wanted to measure the properties of the hand sheets as well as how I wanted to measure out and add the nano material to the sheets. I practiced methods for conditioning the hand sheets and refining the pulp prior to making the hand sheets. I practiced methods for cutting the hand sheets and measuring freeness. I took part in the continuation of the experiment using increased amount of nano material which included 3% and 4% nanofibril and nanocellulose addition to the refined bleached pulp handsheets. I then would compare that data for 3% and 4% to the data found for the 1% and 2% addition of nanocellulos and nanofiber.