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Published in Joseph C. Salamone, Polymeric Materials Encyclopedia, 2020
Natural resins used in paste inks are mainly rosin derivatives. Rosin is mostly obtained from conifers. Three different species are exploited: gum, wood, and tall oil rosins. The considerable carboxylic acidity of rosins, which can be as high as 90% with respect to neutral components, limits their use in printing inks: abietic acid, the main component of rosin, can be isomerised to levopimaric acid, which displays an enhanced reactivity toward polymerization (Scheme III). Rosin is used in the manufacture of various derivatives like “ester gum” (glycerol or pentaerythritol esters of rosin), maleic-anhydride-modified resins (Scheme III) and rosin-modified phenol-formaldehyde resins. Esters of rosin are usually soluble in vegetable oils and hydrocarbons and this allows their extended use in the manufacture of paste inks. Details about the preparation of these resins are available.1,3
Treatment of Paper and Pulp Industry Effluents
Published in Mihir Kumar Purkait, Piyal Mondal, Chang-Tang Chang, Treatment of Industrial Effluents, 2019
Mihir Kumar Purkait, Piyal Mondal, Chang-Tang Chang
Resin acids are tricyclic diterpenes that occur naturally in the resin of tree wood and bark and are transferred to process waters during pulping operations. They are weak hydrophobic acids and are toxic to fish at concentrations of 200–800 µg/L in wood processing wastewaters (McFarlane and Clark, 1988). Resin acids have been measured in Chemi-Thermo Mechanical Pulping (CTMP) wastewaters at concentrations as high as several hundred parts per million, even though the aqueous solubilities of individual resin acids are in the range of 3–6 mg/L. According to Leach and Thakore (1976), 60%–90% of the toxicity in CTMP effluents can be attributed to resin acids alone. It has been observed that wastewater pH strongly affects the toxicity and solubility of these acids, with measured 96 h LC50s (50% lethal concentration) for resin acids ranging from 0.4 to 1.7 mg/L for rainbow trout (McLeay, 1987). The most commonly monitored resin acids in aqueous pulping discharges include abietic acid, dehydroabietic acid, neoabietic acid, pimaric acid, isopimaric acid, sandaracopimaric acid, levopimaric acid, and palustric acid. Isopimaric acid is considered to be the most toxic amongst all resin acids.
Effect study of modulation of molecules of natural resin from black and Halepensis pinus in the removal of humidity from diesel fuel
Published in Petroleum Science and Technology, 2018
Constantinos Tsanaktsidis, Adams Stimoniaris, Spiros Bousios, Konstantinos Spinthiropoulos, George Tzilantonis, Apostolos Scaltsoyiannes
Several studies have been carried out on the characterization and composition of P. halepensis oleoresin. The main components are neutral monoterpenes (mostly α-pinene) and diterpene acids. Neutral diterpenes and sesquiterpenes are also present at appreciable to moderate amounts. Several compositions, exhibiting bicyclic diterpenes (labdanes), tricyclic diterpenes (abietanes and pimaranes), and macrocyclic diterpenes (cembranes) as main components have been reported in the literature depending on the pine species and the geographical origins (Sunzel et al. 1997; Coppen et al. 1998; Arrabal et al. 2002; Karanikas et al. 2010) (Figure 2). Only a few studies reported the chemical composition of resins of P. nigra. The chemometric analysis of the P. nigra oleoresin, identified 15 compounds (Figure 2), i.e., eight resinic acids (abietic acid 1, dehydroabietic acid 2, neoabietic acid 3, palustric acid 4, levopimaric acid 5, isopimaric acid 6, pimaric acid 7a, and sandaracopimaric acid 7b), six neutral diterpenes (pimaral 7c, pimarol 7d, isopimaral 8, isocembrol 9a, 4-epi-isocembrol 9b, and cembrene 10), and one monoterpene (α-pinene 11) (Rezzi et al. 2005).