SOY CHEMICALS FOR PAPER PROCESSING - Soy New Uses

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Internal Sizing AgentsInternal sizing agents act to impart a surface optimized for print sharpness by controllingpenetration of liquids by changing the contact angle of the surface. Internal sizing agents alsoimprove the surface strength and internal bond values. Sizing agents can be added to thepapermaking stock (internal) or applied as a surface coating at the size press located in themiddle of the dryer sections. Internal sizing agents can be:• Natural rosins have been used in the acid process for over a hundred years andfrequently require a fixative such as aluminum sulphate or PAC (polyaluminiumchloride). Rosins are most effective in the acidic pH range from 4-7.5 (with PAC).Cationic Rosins are made using cationic starch or PAC.• ASA - Alkenyl succinic anhydrides contain an anhydride ring to impart hydrophobicityand have a high reactivity with cellulose.• AKD -Alkyl ketene dimers have been used commercially for 40 years, and are synthesizedfrom fatty acids. They are much less reactive than ASA.• Cationic starch is often used in small percentages (1%) in the wet-end to impartstrength. Several modifications of starch include cationic, hydroxyl alkyl, oxidizedstarches and starch acetates. Starch performance is enhanced when poly aluminumchloride is present in the furnish.Retention and Drainage AidsRetention and drainage aids are used to anchor papermaking stock components in the sheetduring the forming process, while at the same time promoting the free drainage of water. It isthe fines, short fibers, fillers and other wet end chemicals which have a tendency to be washedout as the water drains from the paper mat. In a balanced system, water is released from thestock improving machine speeds and reducing drying costs resulting in a more stable processand a reduction in fines lost to effluent. The success of a retention system depends on severalfactors including furnish type (virgin or secondary) amount of filler and broke (scrap paperrecycled within the mill), conductivity and machine speed. Closed systems produce higherconductivity and greater chemical concentrations.Retention aids can be based on organic or inorganic chemicals and often multi-componentpackages. Flocculants adsorb on particles and cause destabilization mainly by bridging or bycreating patches of positive charge on the solid surfaces. They carry active groups whichcounterbalance the charge of the particles. Retention aids from inorganic components are basedtypically on either aluminum species, on montmorillonite clays or on polysilicate materials. The19
aluminum compounds, such as aluminum sulphate (alum), have a coagulating and a chargeneutralizing action. The three main types are:• Single Component - Medium to high molecular weight polyacrylamide, alum or PAC maybe the single component.• Dual Component - A cationic and an anionic component are added separately. Thecationic component can be starch, synthetic polymer or guar gum and the anioniccomponent can be an anionic polymer or a microparticle. The most common syntheticpolymers are those based on polyacrylamide. Polyvinyl amines, polyethylene-imines,polyamides-amines, polyamines, polyethylene-oxide and sulfonated compounds areutilized to a much smaller extent.• Multi-Component - Polyaluminium chloride (PAC), polyDADMAC or a cationic resin isadded to neutralize anionic substances which can interfere with the retention. Enzymesystems based on cellulase or hemicellulase are also used.Dry Strength ResinsDry strength resins increase the internal bond strength and tensile strength of paper byincreasing bonding sites on fibers or by providing stronger bonds. These include:• Cationic starch - has a greater affinity, being positively charged to negatively chargedfibers under standard papermaking conditions. Typical additions in the wet-end of 0.5 -1.5%.• Amphoteric starches - are frequently used in multi-component furnishes and areeffective over a higher pH range. Starch also is used to improve drainage and retention.• Synthetic aids - like low molecular weight polyacrylamides increase the strength of thefiber-fiber bond when added at 0.2 - 0.5% dry basis on fiber. These can be cationic oranionic in nature.• CMC - carboxymethyl cellulose can be used alone or in conjunction with another drystrength aid. CMC increases the negative sites on the fiber which makes it morereceptive to cationic starch in later additions. CMC is added in the pulp at levels that are0.3 - 0.5% per dry basis on fiber.Surface TreatmentsSizing agents are used to fill surface voids to optimize the penetration of ink. Surface sizes areapplied during the dryer stage. In contrast to internal starch, surface starch, that is applied atthe size press, is cheaper (corn-based) but requires more (5%) to reduce viscosity which allowsfor greater surface coverage. Ethoxylated or oxidized starches and blends of starches with non-20
Page 4 and 5: FIGURES1. Classification of Paper G
Page 6 and 7: EXECUTIVE SUMMARYThis report has be
Page 8: soy derivatives in heated, aqueous
Page 11 and 12: Wood logs are delivered to the mill
Page 13 and 14: In paperboard applications, special
Page 15 and 16: FIGURE 3GLOBAL PAPER AND PAPERBOARD
Page 17 and 18: FIGURE 5COST SAVING STRATEGIESCOST
Page 19 and 20: Wood Chips and PulpingThe process o
Page 21 and 22: Fluff pulps primary come from softw
Page 23: PAPER CHEMICALSChemical additives c
Page 27 and 28: RECYCLINGThe growth of paper recycl
Page 29 and 30: Recycle processes generally include
Page 31 and 32: FIGURE 14POTENTIAL CONTAMINANT SOUR
Page 33 and 34: FIGURE 15MARKET DEMAND FOR PULPING
Page 35 and 36: strength additive, Lionsurf ® , Hy
Page 37 and 38: The amphoteric nature of protein co
Page 39 and 40: Agenda 2020 created in 1994 as a pa
Page 41 and 42: 1. Entrance into the market in esta
Page 43 and 44: APPENDIX IRef: Handbook for Pulp &
Page 45: REFERENCESGIA - Global Industry Ana

SOY CHEMICALS FOR PAPER PROCESSING - Soy New Uses

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