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Properties and Control of “Stickies” in Paper Recycling*

Published online by Cambridge University Press:  29 November 2013

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Large amounts of waste paper are generated every day and interest in its reuse has increased steadily due to environmental concerns and improved economics. In 1990 in the United States, for example, 28.9 million tons of recovered papers were collected for recycling. By 1995, that amount is expected to increase to almost 40 million tons with a collection rate of almost 40%. To facilitate the use of secondary fibers, sticky contaminants, or “stickies,” must be controlled.

Classification and Properties of Stickies

Recovered paper bales usually contain extraneous materials such as sand, glass, staples, nails, inks, coatings, plastic, styrofoam, wax, EVA (ethylene vinyl acetate), and SBR (styrene butadiene rubber). A particularly troublesome contaminant in recovered paper is “stickies” which, in their original state, were used as paper adhesives. Inks and coatings can also be a source of stickies. Inks are primarily composed of a pigment, liquid vehicle, binder, and modifier. Coating formulations contain several ingredients that can be classified as pigments, binders, and additives, such as plasticizers, thickeners, dispersants, dyes, preservatives, and defoamers. Note that both inks and coatings mixtures contain binders which contribute to the stickies problem. Common binders used in inks are hydrocarbon resins and rosin esters while those used in coating formulations include starch, soya protein, acrylics, and polyvinyl acetate. An overview of stickies was presented by Moreland.

Stickies can be classified into three categories: hot melts, pressure-sensitive adhesives, and latexes. Although wax can be a contaminant, it is not included separately because it is similar to and an important ingredient of most hot melts.Contaminants such as plastics and styrofoam are also excluded from this discussion because they are not stickies.

Type
Reprocessing Paper and Wood-Based Materials
Copyright
Copyright © Materials Research Society 1994

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Footnotes

*

This article is a modification of “Properties and Control of Stickies,” published in Progress in Paper Recycling, November 1991, p. 54.

References

1.Edwards, J.R., “Future Trends in the Secondary Fiber Industry,” Progress in Paper Recycling 1, No. 1 (November 1991) p. 24.Google Scholar
2.Wand, R.W., “Paper Recycling's Contaminant Barrier,” Proc. Contaminant Problems and Strategies in Wastepaper Recycling Seminar Notes (April 24–26, 1989) p. 3.Google Scholar
3.Wasilewski, O., “Composition and Chemistry of Novel Inks Used in the Newspaper Industry and Deinking,” Proc. TAPPI Pulping Conf., Book 1 (November 1–5, 1987) p. 25.Google Scholar
4.Moreland, R.D., “Stickies Control by Detackification,” Proc. TAPPI Pulping Conf., Book 1 (October 26–30, 1986) p. 193.Google Scholar
5.Wade, D.E., “Sticky Pacification with Synthetic Pulps,” Proc. TAPPI Pulping Conf., Book 3 (November 1-5, 1987) p. 579.Google Scholar
6.Garbutt, T., “The Behavior of Stock Contaminants Embedded in Newsprint Webs with Respect to Pressroom Break Activity,” Proc. TAPPI Pulping Conf., Book 1 (October 22–25, 1989) p. 167.Google Scholar
7.Smith, S.E., “Stickies Properties and the Relationship to their Removal,” Progress in Paper Recycling 1, No. 1 (November 1991) p. 69.Google Scholar
8.McKinney, R.W.J., “A Review of Stickie Control Methods, Including the Role of Surface Phenomena in Control,” Proc. TAPPI Pulping Conf., Book 1 (October 22–25, 1989) p. 177.Google Scholar
9.Doshi, M.R., “Additives to Combat Sticky Contaminants in Secondary Fibers,” TAPPI Pulping Conf. (1989) p. 81.Google Scholar
10.Jackson, P., Tappi J. 72(5) p. 263.Google Scholar
11.Lindsay, M., “Recent Developments in High Consistency Soaking and Screening of Secondary Fiber Furnishes,” Proc. TAPPI Pulping Conf., Book 1 (October 24–26, 1983) p. 151.Google Scholar
12.Bouchette, M.P., “Steam Explosion Technology and Fiber Recycling,” Proc. TAPPI Focus 95+ Landmark Paper Recycling Symp. (March 19–21, 1991) p. 321.Google Scholar
13.Halonen, L. and Ljokkoi, R., “Improved Screening Concepts,” Proc. TAPPI Pulping Conf., Book 1 (October 22–25, 1989) p. 61.Google Scholar
14.Koffinke, R.A., “Screening and Cleaning,” TAPPI Pulping Conf., (April 24–26, 1989) p. 33.Google Scholar
15.Eck, T.H., Rawlings, M.J., and Heller, P.A., “Slotted Pressure Screening at Southeast Paper Manufacturing Company,” Proc. TAPPI Pulping Conf., Book 1 (November 3–7, 1985) p. 41.Google Scholar
16.Moreland, B.A., “Contaminant Profiles in Secondary Fiber Systems,” Proc. TAPPI Pulping Conf., Book 3 (November 1–5, 1987) p. 701.Google Scholar
17.Bliss, T., “Centrifugal Cleaners and Their Applications in Stock Preparation Systems,” Secondary Fibers Course Notes, Doshi & Assoc. Inc. (June 12–14, 1990) p. 178.Google Scholar
18.Chivrall, G.B. and McCool, M.A., “The Uniflow Centrifugal Cleaning Philosophy in Light Contaminant Removal,” Proc. TAPPI Pulping Conf., Book 2 (October 24–26, 1983) p. 685.Google Scholar
19.Marson, M., Pulp Paper 64 (6) (June 1990) p. 93.Google Scholar
20.Williams, G.R., “Physical Chemistry of the Absorption of Talc, Clay and Other Additives on the Surface of Sticky Contaminants,” Proc. TAPPI Pulping Conf., Book 3 (November 1–5, 1987) p. 563.Google Scholar
21.Hoekstra, P.M. and May, O.W., “Developments in the Control of Stickies,” Proc. TAPPI Pulping Conf., Book 3 (November 1–5, 1987) p. 573.Google Scholar
22.Dykstra, G.M. and May, O.W., “Controlling Stickies with Water Soluble Polymers,” Proc. TAPPI Pulping Conf., (October 22–25, 1989) p. 81.Google Scholar
23.Kenney, R.M. and Engstrom, G.C., “New Technology for Stickies/Pitch Control with Increased Production/Profitability,” Proc. TAPPI Pulping Conf., Book 2 (October 30–November 2, 1988) p. 339.Google Scholar
24.Goldberg, J.Q., “Use of Zirconium Chemical in Sticky Contaminants Control,” Proc. TAPPI Pulping Conf., Book 3 (November 1–5, 1987) p. 585.Google Scholar
25.Ormerod, D.L. and Hipolit, K.J., “Aluminum Control Prevents Stickies Problems,” Proc. TAPPI Pulping Conf., Book 3 (November 1–5, 1987) p. 597.Google Scholar