The Research Of Synthesis And Applied Properties Of Hydrophobic Triazine Cationic Starch Derivatives

The physical and chemical properties of hydrophobic modified products of starch and its derivatives are so excellent that they are widely applied in petroleum exploiting, paper making, soil improvement, wastewater treatment, etc. The modified starch was synthesized by hydrophobic modification for starch, in which the2,4-bis(butyl-amino)-6-chloro-[1,3,5]-triazine(BBAT) and 2,4-bis(diethylamino)-6-chloro-[1,3,5]-triazine (BDAT) were chosen as hydrophobic reagents. And the synthesizing technology and the performance of modified starch were investigated by optimizing reaction conditions.2,4-bis(butylamino)-[1,3,5]-triazine starches and 2,4-bis(diethylamino)-[1,3,5]-triazine starches were synthesized from starch in DMSO, in which BBAT and BDAT were used as the hydrophobic reagent. The best reaction conditions of the synthesis of BBAT were confirmed by conditional experiments. And the yield was 93.9% obtained under the optimized conditions, in which the pH value and reaction temperature were 6.0 and 30℃, respectively. The influences of reaction temperature, reaction time, the volume of solvent, and the proportion of materials on the DS and reaction efficiency were investigated for the grafting reaction of starch with BBAT. The DS and reaction efficiency of starch derivatives were respectively 0.29 and 58% under the optimum experimental condition, in which the reaction temperature, reaction time, the volume of solvent and the ratio BBAT and starch were 130℃, 12 h,50mL and 0.5, respectively.The analogous method was applied to the synthesis of BDAT. The best reaction conditions of synthesis of BDAT were confirmed by conditional experiments. And the yield was 93.5% obtained under the optimized conditions, in which the pH value and reaction temperature were 6.0 and 35℃, respectively. Based on BDAT as the hydrophobic reagent, a new type of modified starch, was synthesized from starch. The influences of reaction temperature, reaction time, the volume of solvent, and the proportion of materials on the DS and reaction efficiency were investigated for the grafting reaction of starch with BDAT. The DS and reaction efficiency of starch derivatives were respectively 0.28 and 56% according to the optimum experimental condition, in which the reaction temperature, reaction time, the volume of solvent and the ratio BDAT and starch were 130℃, 10h,60mL and 0.5, respectively.The structures of synthesized productions characterized by IR,1HNMR were confirmed as 2,4-bis(butylamino)-[1,3,5]-triazine starches and 2,4-bis(diethylamino)-[1,3,5]-triazine starches. The difference of crystalline forms between BBAT and reactant was analyzed by X-Ray Diffraction (XRD). The change of gelatinization temperature caused by starch modification was investigated by differential scanning calorimetry (DSC). On the basis that the molar substitution (DS) of BBAT was 0.3, the gelatinization temperature of BBATS was between 120℃and 130℃. The results of DSC showed that the temperature resistance properties of starch were improved by the grafting reaction of starch with BBAT, as well as the gelatinization temperature of modified starch. Thus, the applicability of starch was widened by the hydrophobic modification for starch.Compared the solubility of BBATS and BDATS,we have discoveried that BDATS was better than BBATS.When pH value was 5.0,two modified starches had good hydrophobicity.So BBAT and BDAT were hydrophobic reagents.