Incorporation into paper of cellulose triacetate films containing semiconductor nanoparticles
- 321 Downloads
CdSe/ZnS quantum dots (QDs) were embedded in films of cellulose triacetate (CTA) to give clear films with the broad absorbance and well-defined, size-tunable fluorescence characteristic of QDs. The relative quantum yields of the QDs in polymer were compared to that of the initial QDs dispersed in toluene. Alkaline hydrolysis of the film surfaces to regenerated cellulose rendered the previously hydrophobic CTA film surfaces hydrophilic and compatible with aqueous papermaking. Films containing combinations of different sized QDs gave more complex emission patterns. Small pieces of fluorescent films were added to pulp slurries and incorporated into laboratory paper sheets through hydrogen bonding between the regenerated cellulose film surfaces and cellulosic pulp fibers. The film system (cellulose ester bulk/cellulose surface) can be used to incorporate hydrophobic particles or molecules compatible with solutions of cellulosic polymers into paper products at both high and low loadings. QDs in paper may prove useful for security applications, such as sheets with unique optical signatures.
KeywordsCellulose triacetate CdSe/ZnS quantum dots Fluorescence Paper
We thank NSERC Canada and FPInnovations/Paprican for financial support and the Centre for Self-Assembled Chemical Structures (CSACS) for use of laboratory equipment. T. A. thanks Dr. N. Ulkem and J.M. Berry for helpful discussion.
- Chen Y, Xiong X-P, Yang G, Zhang L-N, Lei S-L, Liang H (2002) Characterization of regenerated cellulose membranes hydrolyzed from cellulose acetate. Chin J Polym Sci 20(4):369–375Google Scholar
- Lee J, Sundar VC, Heine JR, Bawendi MG, Jensen KF (2000) Full color emission from II to VI semiconductor quantum dot-polymer composites. Adv Mater 12(15):1102–1105. doi: 10.1002/1521-4095(200008)12:15<1102::AID-ADMA1102>3.0.CO;2-J CrossRefGoogle Scholar