Development of functional agent release fabric using B-cyclodextrin inclusion compound

Abstract

The β-Cyclodextrin inclusion compounds were attached to the 100% cotton and 50/50 blend cotton/polyester fabrics using Sol-gel, prepared from 3-Glycidoxypropyltrimethoxysilane (GPTMS) and Tetraethoxy orthosilicate (TEOS). The cotton and polyester/cotton fabrics were treated with Sol-gel, which was attached with cotton cellulose through covalent bonding, while in the polyester portion attaches to the Sol-gel through a secondary bonding. β-Cyclodextrin molecules were held in place in the micro-porous structure of a Sol-gel-network and thus attached to the fabric. Aromatherapy oil, having eucalyptus, lavender and lemon fragrances, were applied to the treated fabrics by a selected application method. The durability of these fragrances on fabrics was rated by four judges over six weeks; and up to six washings. The scent ratings decreased over six weeks and six washing; however, the fabrics continued to have a decreased fragrance after, the six weeks. β-Cyclodextrin was also attached to the textile fabric by esterification reaction with citric acid in the presence of the catalyst sodiumdihydrogenphosphate. Cross-linking occurs because of the presence of three carboxyl groups in citric acid that are able to bind with the hydroxyl groups of β-Cyclodextrin and cotton cellulose. As a consequence of crosslinking between the citric acid, β-Cyclodextrin and cellulose in fabric, the β-Cyclodextrin inclusion complex gets firmly grafted to the textile fabric. The active agent used in the inclusion complex was Thyme (Thymus vulgaris) essential oil which has a strong smell/fragrance. Over a period of time and subsequent wash-cycles, the retention of smell was determined by employing a subjective rating technique. Thymol present in Thyme essential oil applied on the fabric was also determined by colorimetric quantitative estimation.