One-stage photoinitiated RAFT dispersion polymerization - Reaction parameters for achieving high particle size uniformity
One-stage photoinitiated RAFT dispersion polymerization - Reaction parameters for achieving high particle size uniformity
复制标题
DOI：
10.1016/j.polymer.2014.04.006
复制
发表时间：
2014-05
期刊：
影响因子：
4.6
通讯作者：
Jianbo Tan;Xin Rao;Danfeng Jiang;Jianwen Yang;Z. Zeng
中科院分区：
文献类型：
--
作者：
Jianbo Tan;Xin Rao;Danfeng Jiang;Jianwen Yang;Z. Zeng
研究了一步法光引发RAFT分散聚合（PRDP）。结果发现，RAFT剂的结构对颗粒形态有很大的影响。羧基功能化的三硫代碳酸酯，包括S，S′-双（α，α′-二甲基-α″-乙酸）三硫代碳酸酯（BDMAT）、S-1-十二烷基-S ′-（α，α′-二甲基-α″-乙酸）三硫代碳酸酯（DDMAT）、S-1-乙基-S ′-（α，α′-二甲基-α″-乙酸）三硫代碳酸酯（EDMAT），是制备高单分散微球的合适RAFT试剂。GPC迹线表明，由于与光引发剂浓度相比低的RAFT剂浓度，聚合不遵循典型的受控/活性过程。在稳定剂和光引发剂的浓度范围很宽的情况下，粒径和均匀性变化很小。即使在低稳定剂浓度（5wt%PVP）下也获得了高度单分散的微球。增加单体浓度导致粒径增加，指数为0.63，这与常规分散聚合的规模相似。微球在单体浓度为5 - 15wt%时是单分散的。
One-stage photoinitiated RAFT dispersion polymerization (PRDP) has been studied. It was found that the structure of the RAFT agent has a strong influence on the particle morphology. Carboxyl-functionalized trithiocarbonates, including S,S′-bis(α,α′-dimethyl-α″-acetic acid) trithiocarbonate (BDMAT), S-1-dodecyl-S′-(α,α′-dimethyl-α″-acetic acid) trithiocarbonate (DDMAT), S-1-ethyl-S′-(α,α′-dimethyl-α″-acetic acid) trithiocarbonate (EDMAT), were found to be suitable RAFT agents for preparing highly monodisperse microspheres. GPC traces suggested that the polymerization does not follow the typical controlled/living process due to the low RAFT agent concentration in comparison with photoinitiator concentration. Particle size and uniformity changed very little with a wide range of concentrations of the stabilizer and photoinitiator. Highly monodisperse microspheres were obtained even at low stabilizer concentration (5 wt% PVP). Increasing the monomer concentration led to an increase in particle diameter with an exponent of 0.63, which is similar in scale to conventional dispersion polymerization. The microspheres were monodisperse at monomer concentrations ranging from 5 to 15 wt%.