基于纳米尺寸低聚硅倍半氧烷潜香体的合成、表征及其香料醛分子缓释性能研究

在功能性香精与香料的应用中,香气怡人与留香持久是需要长期挑战的目标.为了达到该目标,通过形成可切断的共价键来实现香料的缓释留香是有效的途径之一.基于此,本文合成了一系列基于纳米尺寸的低聚硅倍半氧烷(POSS)基体、缩醛结构作为键链的纳米潜香体.该类潜香体在温和条件下能够缓慢地释放香料醛分子.模拟仿生的酸性环境条件,研究了pH对潜香体释放香料分子的影响,发现酸性强弱对香料分子的释放有着重要的关系, pH值也与缩醛键链接的化学键的断裂成正相关关系.在弱酸环境中,释放相对较慢,达到释放平衡的时间相对较长,具有优异缓释的效果.此外,利用该类新颖的潜香体对丝绸、纸张进行负载,并研究了仿生环境下的香料醛分子的释放,与单纯香料醛分子对照样进行了对比和讨论.

Controllable release of volatile aldehydes from polyhedral oligomeric silsesquioxane-based pro-fragrances

In the area of functional flavors and fragrances, the effective aroma and fragrance lasting are long-term challenges. To achieve this goal, an effective way is forming and cutting-off fragile covalent bonds of pro-fragrances along with controlled release of fragrances. We here report a new family of nanocarrier-based pro-fragrances, which have a high affinity to silk textiles and papers. The new pro-fragrances were prepared by using polyhedral oligomeric silsesquioxane(POSS) with perfume aldehydes, in which the formed acetal group as a linker that serves to bind the fragrance molecules allowed slow release of aldehyde molecules via hydrolysis reactions. The controllable release of volatile aldehydes was investigated in aqueous suspensions by headspace solid-phase micro-extraction analysis in combination with gas chromatography. The results show that the release of fragrances from this pro-fragrance system with headspace concentrations are 5–10 times slower than the free aldehydes.