Study On The Synthesis $ Application Of Cationic White Rosin Size

That neutral sizing replacing acid one has become an inevitably developing trend in paper industry Output of rosin is great in our country, and its yearly output is over 400,000 tons In order to completely utilize our resource, and to size at neutral PH with rosin size, a new cationic white rosin size was developed in this paper It had good sizing property under PH 5-8 The partical of the sizing agent was composed of that of cationic rosin ester and rosin We mainly probed the synthesis of cationic rosin ester ,maj or affective factors on sizing and the application of sizing agentFirstcationic rosin ester was made from rosin, epichorohydnn and triethylamine Its forumulas was established asC19H29COOCH2CH(OH) CH2N~ ( C2H5)3 Cflby elemental analysis, IR etc The processing condition optimized by orthogonal tests was (Weight ratio) rosin epichlorohydnn triethylamine= 1 1 1 1 ,reaction temperature 100 0C ,reaction time 3 5h Using the processing condition, linear mathethmatics model was set up as following y~ =u+?, +b2 +c, With it the theoretically calculated value of the ester conversion of rosin was 91 38%, it was identical with measured oneSecondZeta-potential of cationic white rosin size emulsion was determined +3Omv by XYZ- 1 microelectrophoresis Zeta-iotentiometer The emulsion had small diameter, uniformly dispersed micropartical, low viscosity, high solid content, big ratio of free rosin and good stabilityThirdPrimanly by applying quadratic regression orthogonal composite method, a mathematical model was founded between the ratio of rosin to rosin ester(x1),the dosage of PAM(x2) , the dosage of A12(S04)3(x3) and the sizing degree(y) influenced by above three factors to bleached bagasse pulp with the3dosage of sizing agent 1 5%, PH value of stock 7 The mathematical model was as followingy =28 0+0 8454x1+0 681x2+0 718X3+0 675x1x2-0 4x1x3-0 475x2x3-2 513x12-306x~2-l 011x32The effects of each other and interaction among factors on the sizing degree were studied with model analysis With the method of extreme value to mathematical model, the optimum furnish was calculated Its theoretical maximal sizing degree is 28 2s,and the measured one is 26 is with the furnishFourthEffects of sizing PH, dosage of sizing agent, chemical additives and CaCO3 filler on sizing effect were discussed in this paper The optimum furnish of additives for bleached bagasse pulp sizing with cationic white rosin size was belowcatiomc white rosin size 1 5% , PAM 0 7% ,A12(S04)3 1 2% ,CaCO3 15%FinallyCompared with common white rosin size, the handsheets sized with cationic one had bigger breaking length, folding endurance, burst index and better ageing resistance of paper...