Resin heating value

The fuel properties of wood can be summarized by ultimate and proximate analyses and deterrnination of heating value. The analytical procedures are the same as those for coal, but with some modifications. Analytical results generally vary about as much within a species as they do between species, except that softwood species generally have a higher carbon content and higher heating values than hardwood species because of the presence of more lignin and resinous materials in softwood species (see Fuels from waste). 

Butanediol, otherwise known as 2,3-butylene glycol (2,3-BD), is a valuable chemical feedstock because of its application as a solvent, liquid fuel and as a precursor of many synthetic polymers and resins. With a heating value of 27,200 J/g, 2,3-BD conq>ares favorably with ethanol (29,100 J/g) and methanol (22,100 J/g) for use as a liquid fuel and fUel additive (213). Dehydration of 2,3-BD yieldsthe industrial solvent methyl ethyl ketone which is much more suited as a fuel because of its much lower boiling point. Further dehydration yields... 

T5 ical melting temperatures and melting heat values of HDPE geomembranes or the associated degrees of crystallinity, calculated from the melting enthalpy with an extrapolated value of 293 J/g for a fully crystallised HDPE material, are displayed in Tables 2.2 and 3.5. The standard OIT values of well-stabilised HDPE resins are supposed to be > 20 min at 210 °C (Muller 1999a) and > 100 min at 200 °C (GRI 1998) and the high-pressure OIT values > 400 min at 150 °C and 3.4 MPa (GRI 1998). 

Wood, a renewable source, is not an important industrial fuel today. However, its use continues in some mral areas where it is often supplemented with liquid propane. In some underdeveloped countries, wood is still the principal source of energy. Dry wood contains from 1% to 12% moisture whereas green wood contains from 26% to 50% water. The resinous woods, like pine or cedar, yield about 18.5 MJ/kg of air-dried wood or, allowing for the moisture content, about 21 MJ/kg on a dry weight basis. Hardwoods have a heating value of about 19.4 MJ/kg. The energy available in present forest stocks is estimated to be equivalent to about 270 x 10 t of coal or about 2/3 of the equivalent oil reserves. 

Peat is formed when dead vegetation is saturated with water which prevents the action of aerobic bacteria. Thus, most of the carbon of the cellulosic matter is retained, and with ageing, peat is formed. It accumulates at an average rate of 0.7 mm/year or worldwide at 210 Mt of carbon. Canada (40%) and Russia (36%) have more than 3/4 of the world s peat land (320 Mha or 150 x 10 Mt of carbon). In Russia, peat deposits occupy about 1/10 of the total country s terrain. It is a spongy watery mass when first obtained from the peat bog. Six toimes of dry peat yield about 1 t of fuel. A commercial grade of peat contains about 25% water. Air-dried peat has a heating value of about 16.3 MJ/kg. Peat is rich in bitumens, carbohydrates, and humic acids, and as a chemical source, it can yield waxes, paraffins, resins, and oils. Peat also is a source of pharmaceutical and curative preparations as well as a livestock-feed supplement. 

The reserves of oil are limited, and its uses as a fuel for its heat value may eventually become a luxury which few will be able to afford. The petrochemical industry supplies the plastics and resins we use daily, the synthetic fiber for our clothes, and the detergents for our soaps and washings, as well as the chemicals and solvents for industrial use. World petrochemicals amount to about 1/7 of total steel production and about seven times the aluminum produced by weight. 

Neoprene—phenohc contact adhesives, known for thein high green strength and peel values, contain a resole-type resin prepared from 4-/-butylphenol. The alkyl group increases compatibiHty and reduces cross-linking. This resin reacts or complexes with the metal oxide, eg, MgO, contained in the formulation, and increases the cohesive strength of the adhesive. In fact, the reactivity with MgO is frequently measured to determine the effectiveness of heat-reactive phenoHcs in the formulation. 

The specification requirements for electrode binder pitch, eg, high C/H ratio, high coking value, and high P-resin content, effectively ruled out pitches from gasworks or low temperature tars. The cmde tar is distilled to a medium-soft pitch residue and then hardened by heating for several hours at 385—400°C. This treatment increases the toluene-insoluble content and produces only a slight increase in the quinoline-insoluble (Ql) material, the latter by the formation of mesophase. 

On further heating the methylolmelamines condense and a point is reached where hydrophobic resin separates out on cooling. The resinification is strongly dependent on the pH and is at a minimum at about pH 10.0-10.5. An increase or decrease of pH from this value will result in a considerable increase in resinification rates. 

This monomer has been used as the basis of a laminating resin and as a reactive diluent in polyester laminating resins, but at the present time its principal value is in moulding compositions. It is possible to heat the monomer under carefully controlled conditions to give a soluble and stable partial polymer in the form of a white powder. The powder may then be blended with fillers, peroxide catalysts and other ingredients in the same manner as the polyester alkyds to form a moulding powder. Similar materials may be obtained from diallyl isophthalate. 

The alkyd resins are of value because of their comparatively low cost, durability, flexibility, gloss retention and reasonable heat resistance. Alkyd resins modified with rosin, phenolic resin, epoxy resins and monomers such as styrene are of current commercial importance. 

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