沥青改性用丁苯胶乳凝胶控制方案

Control of gel content in styrene-butadiene latex for asphalt modification

以丁二烯和苯乙烯为原料,乳化剂十二烷基硫酸钠和十二烷基苯磺酸钠(二者质量比为2.0/1.0)混合物为负离子乳化体系,过氧化二异丙苯与硫酸亚铁(二者质量比为7/1)混合物为引发体系,叔十二碳硫醇为相对分子质量调节剂,采用三段控温模式,制备出沥青改性用丁苯胶乳,研究了配方和工艺条件对胶乳中凝胶质量分数的影响。结果表明,当丁二烯/苯乙烯质量比为(70～75)/(25～30),乳化体系用量为6.0份(质量,下同),引发体系用量为0.2～0.4份时,采用分批加入0.37～0.46份相对分子质量调节剂,可制备凝胶质量分数为10%～20%的沥青改性用丁苯胶乳。

The styrene-butadiene latex for modifying asphalt was synthesized with butadiene and styrene as monomers,the mixture of sodium dodecyl sulfate and sodium dodecyl benzene sulfonate(mass ratio 2.0/1.0)as anionic complex emulsifier,the mixture of dicumyl peroxide and ferrous sulfate(mass ratio 7/1)as initiation system,tert-dodecyl mercaptan as relative molecular mass regulator by three-stage reaction temperature control mode,and the effect of the formulation and operating condition on the gel content in the latex was investigated.The results showed that under the condition of mass ratio of butadiene to styrene(70-75)/(25-30),the amount of complex emulsifier,initiation system and relative molecular mass regulator 6.0,0.2-0.4,0.37-0.46 phr respectively,the mass fraction of gel in the latex was 10%-20%.