两性离子型聚电解质的合成及对二氧化硅分散性能

Synthesis of amphoteric polyelectrolyte and its dispersing ability on silica

摘要:

以甲基丙烯酰氧乙基二甲基胺(DM)与1,3-丙磺酸内酯为原料合成了3-(2-甲基丙烯酰氧乙基二甲氨基)丙磺酸盐(DMAPS)。以过硫酸铵为引发剂、次亚磷酸钠为链转移剂，在水溶液中进行DMAPS本体自由基聚合，制备了两性离子型聚电解质(PDMAPS)，并将其用作二氧化硅分散剂。利用FTIR、1HNMR以及GPC对DAMPS和PDAMPS进行分析与表征，并通过单因素实验和正交实验研究了不同反应条件对聚电解质分散性能的影响。为了使分散的二氧化硅达到最低的黏度和粒径，最优的制备条件如下：反应温度为75℃、反应时间为3h、引发剂加入量为单体质量的1.0%，在该条件下制备的PDMAPS分散性能最佳，当其掺量为0.8%（质量分数）时，粒径分析表明其二氧化硅中值粒径(d50)从21.193μm降低到0.449μm。

Abstract:

3-[N,N-Dimethyl-N-(methacryloyloxyethyl) ammonium] propane sulfonate (DMAPS) was synthesized from methacryloxy ethyl dimethyl amine (DM) and 1, 3-propane sultone. Amphoteric polyelectrolyte poly3-[N,N-dimethyl-N-(methacryloyloxyethyl) ammonium] propane sulfonate (PDMAPS) , which was used as dispersant for silica, was successfully synthesized by the bulk free radical polymerization of DMAPS in water solution using ammonium persulfate as the initiator and sodium hypophosphite as chain transfer agent, and used as dispersant for silica. DMAPS and PDMAPS were well characterized by FTIR, 1HNMR and GPC. Moreover, the influence of different reaction condition on the PDMAPS’s performance was conducted by the method of single factor experiment and orthogonal experiment. In order to achieve the lowest viscosity and smallest mean particle size (d50) for the silica, the optimum preparation condition were obtained as follows: the reaction temperature is 75 oC, the reaction time is 3h, the adding amount of initiator is 1.0% of the monomer, and when the adding amount of PDMAPS is 0.8% to silica, the results showed that the d50 of the dispersed silica reduced from 21.193μm to 0.449μm, which indicated that PDMAPS can be used as potential dispersant for silica.