Study On Preparation Of Guar Gum Deirvatives And Their Application On Paper-making Process Reconstituted Tobacco

Paper-making process reconstituted tobacco is use of tobacco peduncle, dust, brokentobacco pieces and tobacco waste as basic raw materials through paper-making processproduced tobacco sheet. Paper-making process reconstituted tobacco have the characteristicsof recycling waste materials, saving tobacco materials, reducing cigarette cost, etc. Thereconstituted tobacco pulp contains more than30%tiny fibers, tobacco dust and filler. As thereconstituted tobacco process special requires of additives(non-toxic and harmless, easybiochemical degradation, do not affect the tobacco smell of burning), currently, thereconstituted tobacco pulp does not add any additive in the manufacturing process. This leadsto large number of fines loss. Guar gum and its derivatives have broad application value andapplication prospect in increasing the retention and drainage performance of reconstitutedtobacco pulp fines, also it can improve the physical properties of the tobacco sheet because ofits unique physical and chemical characteristics.This thesis studied the preparation and characterization of cationic guar gum(CGG),cationic guar gum acrylamide graft copolymer(CGG-g-PAM) in ionic liquid. Their retentionand drainage aid performance on paper-making process reconstituted tobacco pulp were alsoresearched. First, analysis the properties of paper-making process reconstituted tobacco pulp;and then comparison the effects of retention and drainage aid of CGG, CGG-g-PAM,commodity cationic guar gum and cationic hydroxypropyl guar gum(CHPG) application onreconstituted tobacco pulp; at last, monobasic and binary of microparticle retention anddrainage aid systems were compared. Research and development multifunctional guar gumderivatives as retention and drainage aid and reinforcing agent suitable for wet end process ofpaper-making process reconstituted tobacco.Synthesized chlorinated1-allyl-3-methylimidazole([AMIM]Cl) and chlorinated1-butyl-3-methylimidazole([BMIM]Cl) two kinds of ionic liquids using microwave radiationmethod. Compared continuous microwave radiation method and intermittent microwaveradiation method on the influence of synthesis reaction time, product yield and raw materialconversion. The results showed that intermittent microwave radiation method could shortenthe reaction time in synthesis imidazoles ionic liquid. The conversion of imidazole was close to the yield and the reaction efficiency were higher than continuous microwave radiationmethod. It could reduce the negative effect on product color darken because of the reactionexothermic, so we could get high purity product. The infrared spectrum and the13C-NMRrepresentation confirmed the synthetic reaction.We prepared cationic guar gum in ionic liquids. Studied the effects of the cationicetherification agent dosage, reaction temperature, alkalization time and reaction time ondegree of substitution(nitrogen content) and the viscosity of CGG, then the optimum reactionconditions were determined. Through the polarizing microscope we found that guar gum wasin a swelling state when reacting in ionic liquids, obviously it was a homogeneous reaction.FT-IR and13C-NMR characterized CGG’s structure. It confirmed the etherification reactionhappened on C6position of guar gum molecular unit. SEM analysed the CGG surface formand TG analysis showed that the CGG performance slightly better than guar gum on thermalstability. Compared different kinds of cationic guar gum of nitrogen content, viscosity,rheological properties, molecular weight and molecular weight distribution, the resultsshowed that the cationic guar gum had higher cationic degree of substitution(0.14) andviscosity(904mpa·s) as CTA cationic monomer. The shear performance was better and themolecular weight distribution was more concentrated.Innovative studied ammonium persulfate initiated cationic guar gum and acrylamidegraft copolymerization in ionic liquid. Researched the effect of monomers and cationic guargum mass ratio, initiator and cationic guar gum mass ratio, reaction temperature and reactiontime on graft polymerization parameters, to determine the optimum synthesis conditions.FT-IR and13C-NMR characterized the structure of CGG-g-PAM. Surface morphology wasobserved by SEM. Thermal analysis showed that CGG-g-PAM had two peaks, so theheat-resistant property was better than guar gum. CGG-g-PAM aqueous solution showedpseudoplastic fluid behavior, but the viscosity decreased slower, and at the same shear rate,viscosity was higher than that of CGG and CPAM. Polymerization kinetics showed thattemperature had great influence on polymerization rate. The apparent activationenergy(ΔEappa) was11.6KJ/mol in ionic liquids. The reaction rate of polymerizationdecreased with monomer and CGG mole ratio increasing. The polymer molecular weightincreased and the molecular weight distribution became narrow. The charge characteristics of paper-making process reconstituted tobacco pulp showedthat Zeta potential raised with the ion concentration, pulp consistency and beating degreeincreasing, while reduced with pH increasing. Cationic demand raised with pH, pulpconsistency and beating degree increasing, while reduced with ion concentration raising.Cationic guar gum could significantly reduce cationic demand of reconstituted tobacco pulpsystem and sharp increase Zeta potential.Analysis on fiber performance of tobacco pulp showed that tobacco pulp raw materialscontained many fiber, fiber clusters and tobacco powder after mechanical grind. Microscopyimage showed that tobacco slurry had many peeling fine and tobacco powder. Comparison offour different kinds of cation substitution degree of CGG synthesed in ionic liquid applicatedon tobacco pulp fines. The effect of retention aid showed that the CGG-2of cationsubstitution degree0.14, viscosity904mPa·s had best application effect on paper-makingprocess reconstituted tobacco pulp. The effect of fines first-pass retention which CGG-2applicated on paper-making process reconstituted tobacco pulp was better than merchandiseCGG and CGG synthesed in solvent, while the latter two had effect of considerable.The DS of cationic guar gum had small effect on retention aid properties of graftcopolymer. CHPG had obvious effect on improving FPR of tobacco pulp. With the CHPGcontent increasing from0to0.08%, FPR increased from40.1%to80.5%, improving101%.Comparison of three kinds of guar gum derivatives retention and drainage aid effects onpaper-making reconstituted tobacco pulp, the results showed that CGG-2had better effectthan CGG2-g-PAM and CHPG. CGG-2which synthesed in ionic liquid application onpaper-making reconstituted tobacco pulp had best effect, but if on the industrializationconsideration, cationic hydroxypropyl guar gum which cationic substituted degree was0.08could be used as its replacement.Organic modified bentonite with STAB, SEM, FT-IR, TG and XRD shown that theorganic modifier had been got into the layer of bentonite. We could decide the betterconditions of organic modifying by orthogonal experiment. Binary of microparticle retentionand drainage aid system which contained CGG and bentonite application on paper-makingreconstituted tobacco pulp was researched. We studied the effect of shear rate, pH and theconsistency of electrolyte on binary of microparticle retention and drainage aid system. The results indicated the binary of microparticle retention and drainage aid system had betterresisting shear capacity, wide-ranging of pH application scope and better resisting electrolyteresistance.