Use of Poly-Lactic Acid (PLA) to Enhance Properties of Paper Based on Recycled Pulp


Nowadays, recycled paper is broadly used due to environmental reasons. Furthermore, the addition of starch as a dry strength additive improves the properties of recycled paper. Poly-Lactic Acid (PLA), a product from bio-refinery process, has recently been shown to act as a promising strength additive that could be used in combination with starch to further improve the strength of paper. In this study, the use of PLA of three molecular weights (MW) in combination with four different starches was investigated. Three recycled pulps from different origins, with the kappa number of 27.9 to 66 were used. Paper handsheets were made, and selected paper properties were tested. The results indicate that handsheets properties were influenced by the MW of PLAs, the type of starch used, and the lignin content of the pulp. The paper handsheets made from lignin-rich pulp (pulp A, kappa number 66), combined with 0.1% medium MW PLA (PLA_1) and 0.9% cationic starch containing 0.43% N gave the highest improvement for tensile strength, wet tensile strength, air and water resistance. This result verifies that a higher kappa number pulp has better attraction to the hydrophobic PLA. Moreover, the higher charge cationic starch led to higher tensile strength due to the increase of affinity to the anionic fiber surface. Interestingly, results show that amphoteric starch is a promising substitute for high cationic charge starch when combined with the medium MW PLA to improve tensile strength of paper. This study demonstrated that a starch-PLA blend represents a promising approach in improving properties of recycled paper.

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Doelle, K. , Le, A. , Amidon, T. and Bujanovic, B. (2014) Use of Poly-Lactic Acid (PLA) to Enhance Properties of Paper Based on Recycled Pulp. Advances in Chemical Engineering and Science, 4, 347-360. doi: 10.4236/aces.2014.43038.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] Scott, W.E. (1996) Principles of Wet End Chemistry. TAPPI Press.
[2] Biermann, C.J. (1996) Handbook of Pulping and Papermaking. 2nd Edition, Academic Press Limited, London.
[3] Neimo, L. (1999) Papermaking Science and Technology: Papermaking Chemistry. Fapet Oy, Helsinki, 268-301.
[4] Gong, C., Hasan, A., Bujanovic, B.M. and Amidon, T.E. (2012) Novel Blend of Biorenewable Wet-End Paper Agents. APPI, 11, 41-48.
[5] Hasan, A., Bujanovic, B.M. and Amidon, T.E. (2010) Strength Properties of Kraft Pulp Produced from Hot-Water Extracted Wood Chips within the Biorefinery. Journal of Biobased Materials and Bioenergy, 4, 46-52.
[6] Smook, G.A. (2002) Handbook for Pulp and Paper Technologists. 3rd Edition, Angus Wilde Publications, Inc., 207.

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