No. 61 Mechanism of Deodorizing Effect of MCT-β-CD finished Textile on Ammonia.
Background
Recently, developments of functional fibers with cold or warm sensing, deodorant effect, water-absorbing and quick-drying, antimicrobial property and antistatic property are very active depending on the demand increase of functional clothes make us comfortable.
Monochlorotriazinyl-β-cyclodextrin (MCT-β-CD) is a reactive cyclodextrin. MCT-β-CD finished textile shows various functions like deodorization and fragrance release. Previously, we found deodorizing
effect of MCT-β-CD finished textile on ammonia after washing the textile. However its deodorization mechanism on ammonia was not fully understood.
In this study, we focused acidity of MCT-β-CD to defining the mechanism of the deodorant effect against ammonia.Grafting of MCT-β-CD onto cotton.
Effective deodorization of ammonia was observed by MCT-β-CD finished cotton with washing.
It is well known that aqueous ammonia can not be included in hydrophobic cyclodextrin cavity.
↓
We supposed that MCT moiety of MCT-β-CD would be relate to deodorizing effect of MCT-β-CD on ammonia.
↓
In this study, acidity of MCT-β-CD finished onto cotton was explored.
Experiment
By deactivation of MCT-β-CD, chloride groups on MCT were converted into hydroxyl groups.
The pKa value of deactivated MCT-β-CD was determined with pH dependency of its absorption spectrum.
[Deactivated MCT-β-CD] = 0.006% in 100 mM NaClaq at r.t..
The pH of the solution was adjusted by the addition of HCl and NaOH.
Result
Deactivated MCT-β-CD was confirmed as acid with pKa=5.5.
Conclusions
- Deodorizing effect of MCT-β-CD finished textile on ammonia was increased after washing the textile.
- Acidic hydroxyl group of MCT moiety of MCT-β-CD could be a potent deodorant site for ammonia odor by neutralization reaction.
