Fibre constituent

Figure 6.1 Schematic comparison of a macrocomposite containing 1 pmx25 pm fibres in an amorphous matrix to that of a nanocomposite at the same volume fraction of filler, but containing 1 nmx25 nm fibres. Constituents in any composite the matrix (white), the reinforcement (fibre, red) and the so-called interfacial region (green). Scanning electron micrograph shows E-glass reinforced polyolefin (15 mm) and transmission electron micrograph shows montmorillanite-epoxy nanocomposite (1 nm thick layers)." ...

A significant amount of waste composites is generated each year and the need for a recycling method is becoming a necessity. Environmental Technical Services has developed, with the support of the University of Missouri-St.Louis, a method for recovering valuable constituents from composite materials. The process converts the polymer matrix to lower chain hydrocarbons and fuel gas leaving behind fibres. Mechanical tests of BMC panels, reinforced concrete and compression moulded panels made with recovered fibres were carried out. 10 refs. USA... 

Matrix Components The term matrix component refers to the constituents in the material aside from those being determined, which are denoted as analyte. Clearly, what is a matrix component to one analyst may be an analyte to another. Thus, in one hand for the case of analyses for elemental content, components such as dietary fibre, ash, protein, fat, and carbohydrate are classified as matrix components and are used to define the nature of the material. On the other hand, reference values are required to monitor the quality of determinations of these nutritionally significant matrix components. Hence, there is a challenging immediate need for certified values for dietary fibre, ash, protein, fat, and carbohydrate. Concomitantly, these values must be accompanied by scientifically sound definitions (e.g. total soluble dietary fibre, total sulpha-ted ash, total unsaturated fat, polyunsaturated fat, individual lipids, simple sugars, and complex carbohydrates). 

There is a wide diversity of chemical structures of anthraquinone colorants. Many anthraquinone dyes are found in nature, perhaps the best known being alizarin, 1,2-dihydroxyanthraquinone, the principal constituent of madder (see Chapter 1). These natural anthraquinone dyes are no longer of significant commercial importance. Many of the current commercial range of synthetic anthraquinone dyes are simply substituted derivatives of the anthraquinone system. For example, a number of the most important red and blue disperse dyes for application to polyester fibres are simple non-ionic anthraquinone molecules, containing substituents such as amino, hydroxy and methoxy, and a number of sul-fonated derivatives are commonly used as acid dyes for wool. 

Defoamers and deaeration additives contained in the past mineral oils as active component but they are not anymore used in Europe. In emulsions, mineral oil can amount up to 10% mass content maximum. If defoamers and deaeration additives are used at a maximum of 0.1% in paper production [22], per each ton of paper, a maximum of 1,000 g defoamers and deaeration additives are used which contain 100 g mineral oil. In consideration of a 50% retention on the fibres, a theoretical content of 50 mg mineral oil per kilogramme final paper would result. By using further mineral oil-containing additives, the concentration in the paper can increase. However, only some chemical additives contain mineral oil constituents, and in most cases their proportion is in a range between 1% and 3% maximum related on the additive mass. 

We know that cellulose (chief component of the cell walls of a plant), proteins essential constituents of living cells, rubber, leather and natural fibres like silk, wool, etc. are all polymers and these are known as natural polymers. 

Epoxy resins find a large number of uses because of their remarkable chemical resistance and good adhesion. Epoxy resins are excellent structural adhesives. When properly cured, epoxy resins can yield very tough materials. They are used in industrial floorings, foams, potting materials for electrical insulations, etc. One of the principal constituents in many of the Fibre-reinforced plastics (FRP) is an epoxy polymer. 

Cellulose is reputedly the most abundant organic material on Earth, being the main constituent in plant cell walls. It is composed of glucopyranose units linked pi 4 in a linear chain. Alternate residues are rotated in the structure, allowing hydrogen bonding between adjacent molecules, and construction of the strong fibres characteristic of cellulose, as for example in cotton. 

Note Space filling is achieved by branching, bending or both, of the constituent fibres or lamellae. 

Method 7.5. Determination of neutrai detergent fibre (NDF) or plant cell-wall constituents... 

This is based on the method by Van Soest and Wine (1967) which has been modified according to subsequent recommendations. It is the only fibre determination suitable for non-ruminants. The residue consists of the plant cell-wall constituents cellulose, hemicellulose, lignin, cutin, NDF-insoluble tannin and ash. See the article by Cherney (2000) for current modifications these include the use of amylase to aid in the removal of starch from forages containing grain (Van Soest et al., 1991), which has been adopted by MAFF... 

Hay has been analysed by NIR for crude protein, acid detergent fibre, dry matter, lignin and IVDMD, rapeseed for oil and water and spring field beans for N to name but a few applications. Most macroinorganic constituents of peaty soil can be determined, and moulds have been measured in hay, tall fescue and barley (Malley and Nilsson, 1995). A short bibliography is given below. 

For many thousand years cannabis sativa has been a valuable source of hemp fibre. The (ab)use of its psychoactive constituents has also been know in many cultures for a very long time. With the advent of superior alternative medications the medical use of cannabis extracts faded in the last century. Cannabis was removed from the US Pharmacopoeia in 1942 and from the British Pharmacopoeia in 1976 when it was classified as a drug with no therapeutic benefit. 

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