Cottonseed hairs

Cellulose never occurs in pure form in softwood and hardwood, it constitutes about 40 to 50% of the weight, in flax 70 to 85%, whereas, cottonseed hairs, which are the purest source, contain more than 90% (Table II). In these materials, cellulose macromolecules serve as a structural material within the complex architecture of the plant cell walls. Commercial production of cellulose is concentrated on the highly pure sources like cotton or easily harvested sources like wood. 

So what effect do these differences in stereochemistry and extent of branching have on the uses of these polysaccharides Because of the extended nature of its chains, cellulose is the most common structural component of plants. Cellulose makes up the main component of the cell wall of plants. Wood is approximately 50% cellulose, while fiber-producing plants such as flax, jute, and hemp are 65% to 80%. The seed hairs of cotton are virtually pure cellulose. The long fibers from cottonseed (up to 5 cm long and 9 to 25 jxm in diameter [Franz 1986)) are spun into thread that is then woven into fabric for clothing. Short fibers, called linters, are used as the raw materials for chemical derivatives such as cellulose acetate (see Chapter 4). 

Each cotton fiber is a single, elongated, complete cell that develops in the surface layer of cells of the cottonseed. The mature cotton fiber is actually a dead, hollow, dried cell wall [4,5,43], In the dried out fiber, the tubular structure is collapsed and twisted, giving cotton fiber convolutions, which differentiate cotton fibers from all other forms of seed hairs and are partially responsible for many of the unique characteristics of cotton. The biosynthesis and morphology of the cotton fiber are discussed in more detail later (see Chapter 2). 

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. 

Products and Uses Commonly used in glues, air fresheners, antiperspirants, drycleaning solvents, fingernail polish, hair spray, laundry spray starch, perfumes, after-shave lotions, preservatives, cottonseed, packaging materials, fabric dura-... 

Cotton plantations are intrinsically tied to the history of the erstwhile Confederate States of the USA. Cotton is a crop that, besides fibre (cotton lint), delivers food (cottonseed oil) and feed (meal). For each 100 kg of cotton fibre produced, the plant produces about 150 kg of cottonseed. About 50 cottonseeds are contained in a pod, which opens when it is ripe. After removal of the cotton, the seeds are still covered with fine hairs (linters), which are removed with delintering machines. The linters are used as a chemical cellulose source in personal care products, in batting for upholstered furniture and mattresses, in high-quality paper and for celluloseether production. 

PEG-2 cocomonium chloride Quatemium-81 base, conditioners hair care Laureth-3 phosphate base, conditioners shampoo Laureth-3 phosphate base, cosmetic creams Hydrogenated cottonseed oil base, cosmetic sticks Cetyl palmitate base, cosmetics... 

Cellulose is present in the pure state in the hairs of the cottonseed. Complete acid hydrolysis of cellulose by strong, concentrated mineral acids gives D-glucopyranose in quantitative amounts. Careful partial hydrolysis in the presence of acetic anhydride and sulphuric acid (acetolysis) gives molecules of cellobiose (4-D-glucopyranose-j3-D-glucopyranoside) and trisaccharides which can be hydrolysed by the enzyme emulsin. Hence, it... 

The seed hairs, called lint, are removed by saw-like machines (gins). Slots in the machine allow lint to pass and keep the seed back. Modem gins are multifunctional that also dry, blend and clean the lint and the seed. Packing of the long cotton fibers into bales of 220 kg follows. The seed, 65% by weight and 15% by value, is source of ->cottonseed oil and cotton linters (->cellulose). 

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