Guar Gum Modified By Inverse Emulsion And Its Application In Papermaking Tobacco Slice

Grafting polymerization reaction of guar gum (GG) and acryl amide (AM) was initiated byceric ammonium nitrate (CAN) and nitric acid under stable inverse emulsion system, andgraft copolymer (GG-g-PAM) was applied to papermaking tobacco slice as reinforcing agent.Then grafting polymerization reaction of GG, AM and Methacryloxyethyltrimethylammonium chloride (DMC) was initiated by ceric ammonium nitrate (CAN) and nitric acidunder stable inverse emulsion system, and graft copolymer (GG-g-PAM/DMC) was applied topapermaking tobacco slice as reinforcing agents and retention and drainage aids.The inverse emulsions were prepared with paraffine as oil phase,2.5%guar gum solution asaqueous phase, a mixture of two kinds of surfactants (Span80and OP-10) as the emulsifier,cetanol as co-stabilizer. The effects of HLB value and the dosage of emulsifier, aqueous phasevolume fraction, the dosage of cetanol and stirring rate on type and stability of emulsion wereinvestigated. The optimal conditions for steady inverse emulsion were determined. Steadyinverse emulsion system was discrete, average particle size less than10μm and a narrowparticle size distribution.Grafting polymerization reaction of GG and AM was initiated by ceric ammonium nitrate(CAN) and nitric acid under stable inverse emulsion system. The effects of reactiontemperature, reaction time, initiator concentration and m(AM)/m(GG) on monomerconversion, percent grafting and molecular weight were investigated. The optimal conditionsfor polymerization were determined. The structure of GG-g-PAM was characterized by FT-IR.The surface morphology of grafted polymer was studied by SEM. The DTG data showedGG-g-PAM was not as good as GG. The results showed that the strength of papermakingtobacco slice was improved when added GG-g-PAM.Grafting polymerization reaction of GG, AM and DMC under stable inverse emulsion systemwas further investigated. The effects of initiator concentration, m(DMC-AM)/m(GG),m(DMC)/m(AM), reaction time and reaction temperature on monomer conversion, percentgrafting, cationic degree and molecular weight were investigated. The optimal conditions forpolymerization were determined. The results of FT-IR and SEM showed that AM and DMC had successfully grafted to GG. The DTG data showed the introduction of AM and DMCdecreased the thermo stability of GG-g-PAM/DMC.The application of GG-g-PAM/DMC on papermaking tobacco slice was investigated. Theresults showed that the retention and drainage performance of papermaking tobacco pulp andproperties of papermaking tobacco slice were improved when added GG-g-PAM/DMC. Andthe retention and drainage performance of GG-g-PAM/DMC was better than cationic starchand cationic guar gum.