Repartitioning of co-solvents between particles of latex emulsions was investigated by means of a fluorescence method based on the detection of the amount of co-solvent via the solvatochromic shift of the emission maximum of a fluorescent probe, copolymerized at a low concentration. Complete repartitioning of co-solvents between particles of latex materials with a low T g (ca. 25 °C) occurred within minutes. For a hydrophilic latex with a T g of 68 °C, equilibration was achieved within an hour. Repartitioning was faster for more hydrophobic co-solvents. For a hydrophobic latex of similar T g , co-solvent repartitioning took place on the same time scale, but complete equilibration was not reached. Possibly, there is an additional slow component in the repartitioning, or the prolonged presence of co-solvent causes a structural change in the latex particles that affects the outcome of the experiment.
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机译：通过基于低浓度共聚的荧光探针的发射最大值的溶剂化变色的共溶剂量的检测，通过荧光方法研究了助溶剂在乳胶乳液颗粒之间的重新分配。数分钟内，T g 低（约25°C）的乳胶材料颗粒之间的助溶剂完全重新分配。对于T g 为68°C的亲水性胶乳，在一小时内达到平衡。对于更具疏水性的助溶剂，重新分配的速度更快。对于相似的T g 疏水性胶乳，共溶剂重新分配在相同的时间范围内进行，但未达到完全平衡。可能在重新分配过程中还有其他缓慢的成分，或者助溶剂的长期存在会导致胶乳颗粒的结构发生变化，从而影响实验结果。
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