Cotton seed coat

M., Du, G.C., and Chen, J. (2009) Analysis of the chemical composition of cotton seed coat by Fourier-transform infrared (FT-IR) microspectroscopy. Cellulose, 16 (6), 1099-1107. 

The cotton fibers used in textile commerce are the dried cell walls of formerly living cells. Botanically, cotton fibers are trichomes or seed coat hairs that differentiate from epidermal cells of the developing cottonseed. The cotton flower blooms only for one day and quickly becomes senescent thereafter. On the day of full bloom, or anthesis, the flower petals are pure white in most G. hirsutum varieties. By the day after anthesis, the petals turn bright pink in color and, usually by the second day after anthesis, the petals fall off the developing carpel (boll). The day of anthesis serves as a reference point for all subsequent events in the seed and fiber development. 

The loom state cotton fabric contains about 8-12% natural impurities of total weight of the fibre. These impurities mainly consists of waxes, proteins, pectic substances and mineral matters. In addition to this, the mechanically held impurities called motes are present containing seed-coat fragments, aborted seeds and leaves etc. that clinge to the fibre. Apart from these, the loom-state fabric is also contaminated with adventiteous oils such as machine oils, tars, greases etc. 

Cotton strains and species with green fiber have lamellar layers (up to 26) of suberin and wax deposited alternately with cellulose during formation of secondary walls in the epidermal cells, including fiber cells, of the seed coat. Seeds of cotton with green lint are less permeable to water than those with white lint, indicating that suberin may be involved in regulating water uptake by seeds. 

The preparation of epoxy resins from a large number of vegetable oils such as sunflower, cotton-seed, linseed, vernonia, soybean, castor and Mesua ferrea has been reported. " However, most of these epoxy resins exhibit poor mechanical properties which limit their applications. Vegetable oil-based epoxy resins rather than epoxidised vegetable oils are also used as reactive diluents. These are low viscosity materials used in conjunction with industrial epoxy resins to reduce viscosity and to increase the molecular mass of the latter. As a reactive diluent can also act as a solvent for the resin system, it enables the production of high-solid and low VOC (volatile organic compound) coatings. 

Two main processes are used for removing oil from oilseeds. One uses pressure to force out the oil, and the other uses an organic solvent, usually hexane, to dissolve the oil from the seed. Some seeds, such as groundnut, cotton seed and sunflower, have a thick coat or husk, rich in fibre and of low digestibility, which lowers the nutritive value of the material. It may be completely or partially removed by cracking and riddling, a process known as decortication. The effect of decortication of cotton seed upon the nutritive value of the cake derived from it is shown in Table 23.2. 

Scouring and bleaching of cotton fabrics are also attractive targets for enzyme-based processes, due to the severe environmental impact of these processes. These processes are also very energy demanding. Raw cotton contains about 10% of impurities. Pectins, waxes and coloured components can all be partially removed from raw cotton by enzymatic treatments but the residual seed coating remains a problem. 

Ryser U, Holloway P J 1985 Ultrastructure and chemistry of soluble and polymeric lipids in cell walls from seed coat fibres of Gossypium species. Planta 163 151-163 Ryser U, Meier H, Holloway P J 1983 Identification and localization of suberin in the cell walls of green cotton fibres Gossypium hirsutum L., var. green lint). Protoplasma 117 196-205 Sagisaka S 1976 The occurrence of peroxide in a perennial plant, Populus gelrica. Plant Physiol 57 308-309... 

ANN has made its presence felt in all related aspeets in textile from the fiber cultivation to garment manufacturing. Pattern recognition is one of the areas where ANN has played a significant role. Attempts have been made to identify fibers as well as trash using neural networks and NIR spectrophotometry. Even the animal fibers, merino and mohair have been recognized and classified by She et al. [2]. Cotton colors are also classified based on chromatic differences by the use of neural network. Classification of trash, such as leaf, bark and seed coat, the content of each of these trash particles is important in the sense to deeide the cleaning process. 

The cotton ball consists almost entirely of pure cellulose, which originates from the fibers formed by the upper cell layer of the seed coat. Machine- or... 

Nonabsorbable Natural Sutures. Cotton and silk are the only nonabsorbable sutures made from natural fibers that are stiH available ia the United States. Cotton suture is made from fibers harvested from various species of plants belonging to the genus Gossipium. The fiber is composed principally of ceUulose. The seeds are separated from the cotton boUs, which are carded, combed, and spun iato yams that are then braided or twisted to form sutures ia a range of sizes (Table 4). The suture is bleached with hydrogen peroxide and subsequendy coated (finished or glaced) with starch and wax. The suture may be white or dyed blue with D C Blue No. 9. 

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