| This paper characterized and analyzed the synthesis promoter M-La,and its influence on vulcanization properties of natural rubber was studied.After determining that it has certain promoting effect on vulcanization of natural rubber,the experiment of substituting and compounding of various promoters was designed and carried out.Lanthanum aminobenzoic acid（M-La）was synthesized and characterized by precipitation with sodium hydroxide and lanthanum nitrate in ethanol environment.Infrared analysis showed that the peaks of C-H and C-N were offset by lanthanum.Thermal analysis calculated by weight loss rate,the content of La element in promoter M-La was 25.1%.The content of C,H and N in the synthesis promoter M-La was determined by elemental analysis and its molecular formula was La（C7H6NO2）3·2H2O by combining the results of infrared analysis and thermal analysis.Through the comparison experiment,it is determined that the most suitable vulcanization temperature and curing time of natural rubber traditional vulcanization system is 180℃and 10min.Too low vulcanization temperature will lead to slow reaction or even stagnation,while too high vulcanization temperature will affect the performance of vulcanized rubber.Different amounts of accelerator m-la were mixed into the rubber for comprehensive analysis experiment.According to the calculation of vulcanization parameters,it was found that with the increase of the amount of accelerator M-La,the vulcanization rate of rubber increased from 139 to 227,and the effect of promoting the vulcanization rate was obvious.Vulcanized rubber T10 gradually increased and T90basically remained stable,indicating that the safety of vulcanized rubber processing increased constantly;The results of thermal swelling method showed that the crosslinking density of vulcanized rubber increased from 1.95×10-4 mol/g initially to 2.41×10-4mol/g,indicating that M-La could promote the crosslinking reaction.Based on the above three groups of comparative experiments,it is found that the accelerator m-la has the effect of accelerator on vulcanization of rubber,and can guarantee the processing safety of vulcanized rubber.The synthetic accelerator m-la was designed to test its practical value by substituting and compounding experiments with stearic acid（SA）,zinc oxide（ZnO）and promoters D and DM,respectively.The experimental results showed that the synthetic accelerator M-La could not completely replace SA and ZnO,but when the ratio of the three was 1:3:3.75,it had better curing effect than the traditional formula.And on synthetic promoter M-La replace traditional accelerator D,found in DM experiment:synthesis of accelerator M-La replace the obvious effects of accelerator M on accelerator DM didn’t replace the role,in the further distribution experiments found when not adding accelerator M,promoter M-La and accelerator DM mass ratio of 1:1.6 when vulcanized rubber vulcanization effect is best. |
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