Neutral resins

The major components of candelilla wax are hydrocarbons, esters of long-chain alcohols and acids, long-chain alcohols, sterols, and neutral resins, and long-chain acids. Typically, candelilla wax has a melting point of 70°C, a penetration of 3 drum at 25°C, an acid number of 14, and a saponification number of 55. Principal markets for candelilla include cosmetics, foods, and pharmaceuticals. The FDA affirmed Candelilla as GRAS for certain food apphcations in 21 CFR 184.1976. 

Turpentine is an oleo-resin exuded from the trunks of certain conifers (so-called Scio turpentine is obtained from one of the Terebinthaceae, Pistada terebinthus L.) and consists essentially of resin acids, neutral resins, volatile oil and small proportions of various other substances (succinic acid, bitter principles, colouring matters, water). Distillation of turpentine and rectification of the distillate gives oil oj turpentine, the residue being colophony. By dry distillation of the latter resin oils are obtained. The present chapter deals with the natural product, i.e. turpentine, and with the products obtained from it. 

Fig. 5. Triethylammonium carbonate (7) and trimethylammonium bicarbonate (8)-based commercially available neutralizing resins.

Fig. 5-10. Changes in the resin composition during storage of spruce chips (Assarsson, 1969). 1, Resin acids 2, unsaponificable substances 3, extractive content 4, neutral resin components 5, esterified acids.

Figure 1 compares the dry- and wet-shear strengths of two-ply, Douglas-fir veneer panels bonded with a commercial phenol-formaldehyde resin (basic), a phenol-formaldehyde resin prepared in the laboratory under basic conditions, and an unmodified neutral resin prepared in the laboratory. The shear strengths obtained with these three resins served as control data for further experiments. The dry-shear strengths of panels bonded with the unmodified neutral resin are lower than those for panels bonded with the resins cured under basic conditions however, the wet-shear strengths of panels bonded with the three resins are all... 

Neutral resins formulated with various xylose contents were used to bond Douglas-fir veneers into two-ply panels at 170 °C as opposed to 140 °C used for the basic resins. This temperature was chosen for bonding since differential scanning calorimetry (DSC) showed that the unmodified and modified neutral resins produce a major exotherm at about this temperature, whereas, resol resins cured under basic conditions produce an exotherm at about 140 °C. 

Figure 2. Variation of the dry- and wet- (hatched) shear strengths of two-ply Douglas-fir panels bonded with xylose-modified neutral resins. Moles of xylose per mole of phenol were varied as indicated. The mole ratio of phenol to formaldehyde was 1 2.3.

The amount of wood failure in the two-ply specimens decreases as the amount of modifier in the resin is increased. The wood failure data also indicate that the performance of the modified resin is not severely affected until greater than about 0.6 moles of modifier per mole of phenol has been added to the neutral resin (Figure 4). 

Viscosity of Neutral Resins. The neutral resins, both unmodified and carbohydrate-modified, were very viscous. The resins have a consistency of taffy candy. This might present problems in their utilization with present commercial equipment, although equipment for applying foamed resins might be suitable. 

Some neutral resins can be solubilized in, for example, methanol by vigorous shaking. 

Extract ability. About 60 to 70% of the total modifier added is extractable from resins cured under basic conditions and modified with alditols and methyl glycosides (2). In contrast, only about 0 to 20% of the xylose and prehydrolysate is extractable from samples of cured resin modified with 0.6 moles of either modifier per mole of phenol. Approximately 20 to 30% of xylitol (II), methyl xyloside (III), or glucose (IV) is extractable from neutral resins modified with these carbohydrates, indicating that neutral resins incorporate the carbohydrate more effectively than resins formulated and cured under basic conditions. In addition, free reducing sugars can be used directly. 

Gelbard et al. have prepared a numbor of neutral and acidic supported ammonium chromates. Neutral resins woe found to be generally more effective dian acidic resins. The large differences in leactiviQr between different unbound, soluble alkylammonium chromates (Section 2.7.6.1) are not so pronounced with the polymer-supported oxidants. Some commoits about the reactivity of these supported oxidants woe made (i) quaternary ammonium salts are more reactive than the tertiary pyridinium chromates (ii) the reactivity of a conqilex chromate XCtOr was found to increase as the basicity of X decreases. Best... 

With certain exceptions, cyanoacrylate monomer formulations containing additives e.g. rubbers, high-density neutral resins, silicon dioxide, etc., may hinder accurate and precise analysis using dilution methods. In such cases it may be necessary to prepare samples using destructive techniques, particularly where the levels are very low. Solvent selection for dilution of cyanoacrylate adhesive must be compatible for the entire journey of the sample solution from sample vessel to torch. Failure to do this could cause the cyanoacrylate to polymerise locally and block the entire sample transport system in ICP-OES and can cause serious damage requiring expensive replacements. The solvents suggested in the above dilution methods were found to be satisfactory. 

Low-capacity resins have been prepared specifically for use in ion chromatography by Fritz et al. [30]. The resin used in the separations was a 3 2 blend of neutral resin with low-capacity sulfonated resin giving a final capacity of about 8 jieq/g. Very good efficiency was demonstrated for separation of the alkali cations and alkaline earths. 

There are several methods available for the extraction of bile salts from serum or plasma. The most convenient methods utilize some form of liquid-solid extraction. An early procedure involved the anion-exchange resin, Amberlyst A-26 (S8), but considerable time and effort was required to perform column chromatography and to concentrate the eluate from the column. The introduction in 1972 of the neutral resin, Amberlite XAD-2, improved the ease of extracting bile acids and their conjugates from serum samples (M6). Further improvement occurred in 1977 with the description of a batch extraction technique using the related neutral resin, Amberlite XAD-7 (B5). With this technique, serum is diluted in 0.1 M sodium hydroxide to release bile acids from albumin and mixed with resin for 1 hour. After washing the resin in dilute alkali, bile acids are eluted with methanol, which cdn be removed on a rotary evaporator (B5). 

B16a. Bradlow, H. L., Extraction of steroid conjugates with a neutral resin. Steroids 11, 265-272 (1968). 

By boiling with acids or by continued heating to 200 (392 F.), cholic acid losea the elements of H,0, and is transformed into dystydn a neutral, resinous material, insoluble in H O and alcohol, nparingly soluble in ether. 

Balsam Canada, Canada turpentine balsam of fir. Improperly Bairn a/ Gilead". Liquid oleoresin from Abies belsameo (L.), Mill., Pinaceae. Habit. Canada and Northern U.S. to Va. west to Minnesota- Constil, 27.5% Volatiles (pinene, nopinene, S-phellandrene), 44.5% resin acid (13% abietic, 8% neoabietic). 27% neutral resinous compounds. Ref Lombard et al, Peintures, Pigments, Vemis 34, 106 (1958), CL 52, 12420 (1958). 

It was found, however, that hypercrosslinked sorbents exhibit much higher adsorption capacities. Fig. 11.7 illustrates sorption isotherms for phenol on the biporous sorbents MN-200 and MN-150. The isotherms coincide completely, thus revealing no difference in the phenol adsorption between the two neutral resins that only differ in the size of their macropores [53]. Both MN-200 and MN-150 absorb about 0.4g of phenol per gram of polymer without yet achieving fuU saturation of the resins. This value practically coincides with the amount ofsweUing water that is taken up by the hypercrosslinked polymeric phase of the biporous network. 

Uses Defoamer tor aq. wood, industrial, and automotive coatings, clear and top coats, PU emulsions, amine-neutralized resins, 2-pack PU coatings, PE sol ns. 

Chem. Descrip. Manganese-based drier complex Uses Drier for urethane alkyd lacquers such as floor coatings, water-based coatings such as amine-neutralized resins, water-emulsifiable alkyds, and alkyd-actylics Features Cobalt-free... 

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