Pore size matching up: A novel insight into cotton textile aromatic finishing

Aromatic reservation is one of the key evaluation index of textiles which be finished with fragrant micro-/nanocapsules, and some researches discover that when the fragrant micro-/nanocapsules penetrating into the spacing of textiles, the resulting aromatic textiles own much better carrying capability of micro-/nanocapsules. Based on these phenomena, hence in our research, the matching up between pore sizes of cotton textile and sizes of fragrant micro-/nanocapsules is investigated systematically in order to reveal the size effect on the durability of fragrant micro-/nanocapsules in cotton textile. Firstly, the pore sizes of cotton textile are analyzed by three different techniques: 3D X-ray microscopy (Micro-CT), nitrogen adsorption/desorption method (BET), and mercury intrusion porosimetry (MIP) technique. Based on the pore sizes obtained from MIP technique, citronella oil/chitosan micro-/nanocapsules with three corresponding sizes are prepared and then applied on cotton textiles through vacuum impregnation process. The pore sizes of cotton textile measured by MIP technique decrease from before finishing to after finishing with nanocapsules, which states that nanocapsules are entrapped inside the pores of cotton textile. Finally, the washing durability of aromatic cotton textile is evaluated by headspace-solid-phase microextraction (HS-SPME) technique combining with GC-MS which can keep the fragrant micro-/nanocapsules unbroken to simulate the real sniffing environment. The results show that aromatic cotton textile treated with nanocapsules possesses much better washing durability, which is met up with the results of pore size measurements: More nanocapsules are penetrating into the spacing of cotton textile fibers even the pores in fibers.