Resins, fossilized origins

Natural resins are generally described as solid or semisolid amorphous, fusible, organic substances that are formed in plant secretions. They are usually transparent or translucent yeUow-to-brown colored, and are soluble in organic solvents but not in water. The principal uses for natural resins are in varnishes, printing inks, adhesives, paper size, and polymer compositions. The term natural resins includes tree and plant exudates, fossil resins, mined resins, and shellac. They often have been altered from their original state during isolation and processing. For some appHcations, the resins have been chemically modified to increase their industrial utiUty. 

Amber Organic Origin Fossil resin Yellow//brown/red... 

Copals, sometimes referred to as immature amber, originate from Africa, Asia or central American countries and derive from the Araucariaceae and Leguminosae families. Polymerised communic acid and agathic acid are found as the main compounds in these fossil resins. The extreme hardness of copal results from polymers of resin acids such as ozoic acid, an enantiomer of communic acid that can polymerize and thus enable fossilization [86]. They are still commonly used today for varnishing and protecting wood. 

Liptinites were made up of hydrogen-rich hydrocarbons derived from spores, pollens, cuticles, and resins in the original plant material. Vitrinites were made up of wood, bark, and roots and contained less hydrogen than the liptinites. Inertinites are mainly oxidation products of the other macerals and are consequently richer in carbon. The inertinite group includes fusinite, most of which is fossil charcoal, derived from ancient peat fires. 

Grantham PJ, Douglas AG, The nature and origin of sesquiterpenoids in some Tertiary fossil resins, Geochim Cosmochim Acta 1980. 

Another promising application of NMR spectrometry to archaeological problems deals with fossil resins. These terpenoid polymers, the best known of which is amber, have played a large role in trade relations during prehistoric times since at least the neolithic era, and the determination of their geographic and botanical origin can contribute to our knowledge of this early commerce. 

Within the specific context of this chapter, renewable resources represent the obvious answer to the quest for macromolecular materials capable of replacing their fossil-based counterparts [2, 3]. This is not as original as it sounds, because, apart from the role of natural polymers throughout our history evoked above, the very first synthetic polymer commodities, developed during the second half of the nineteenth century, namely cellulose esters, vulcanized natural rubber, rosin derivatives, terpene resins , were all derived from renewable resources. What is new and particularly promising, has to do with the growing momentum that this... 

ORIGIN/INDUSTRY SOURCES/USES in commercial coal tar in wood preservative sludge chemical intermediate in many miscellaneous applications formation of polyradicals for resins dyestuffs derivatives of fluorene show activity as herbicides and growth regulators in fossil fuels... 

In light of the recently developed high interest in ambers, we decided to discuss these fossilized natural resins as a separate topic. For this reason, even information about fake ambers (mostly synthetic polymers) will be included in this discussion. Ambers have long proved difficult to examine. IR and FTIR spectroscopy provided useful tools in the determination of amber origins, but in a comprehensive review of the subject, Becld stated ... 

Another difference in VAR spectra of geological origin is registered for absorption bands from 800-600 cm- region 622-621 cm-i are ascribed to C-O, C=0 out of plane bands 746-736 cm" are the confirmation of OH and H bonds 676-666 cm" are the confirmation of CH2 bonds. The absence of a double peak at 667 cm-i in the Baltic amber spectra indicates that the contraction-reticulation of the polymeric chain is complete (an aspect related to the older age of the fossil resin, in our case the Baltic species). This region is not so well defined in archaeological samples, especially for Baltic amber (Figs. 2 and 3). 

Resins largely amorphous, solid or half-solid, transparent, odorless and tasteless organic substances, usuaUy of vegetable origin. Tree R. are clashed according to age into fossil R., such as amber, recent fossil R. (several years to centuries old), e.g. copal R and recent R., which occur mostly as balsams fresh from injured trees. Caoutchouc (see) is included with the R. Herbaceous plants produce R., e.g. mastic, but not in any considerable quantity. Mixtures of R. with mucin are called gum R. Solutions of R. are referred to as balsams. The most important animal R. is shellac, produced by the female East Asian scale insect (Tachardia lacca). 

One of the most ancient commercial derivatives is amber, a fossilized resin originating from a group of conifers loosely named Pinus succinifera that grew... 

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