Rosin types

Flux pen, 2 pens, or as needed. Do not use acid flux. HMC Electronics, 186FP Mildly activated rosin, type RMA... 

High stock temperatures can have a negative effect on all the major size types, causing agglomeration of rosin types and hydrolysis of reactive sizes. 

Rosin type (sample) n. Sample of rosin, or a mold of thermosetting plastic material, used as an unofficial standard in grading rosin. Such sample shall be so selected, sized and surface-finished that it will have the form of an approximate 7/8in. cube with at least two opposite faces having smooth parallel surfaces and shall have a color when viewed through these faces which matches within rather narrow tolerances the color of the corresponding official government standard. 

Thus n. Oleoresinous exudation of rosin type. Because of its relative softness it has been used to a small extent in spirit varnishes as a plasticizer. 

The three types of rosin perform differently because of different distributions of resin acids, as well as different types and quantities of impurities. These differences are reflected in end-use performance. 

Composition. Rosin is primarily a complex mixture of monocarboxyUc acids of alkylated hydrophenanthrene nuclei. These constituents, known as resin acids, represent about 90% of rosin. The resin acids are subdivided into two types, based on their skeletal stmcture. The abietic-type acids contain an isopropyl group pendent from the carbon numbered 13. The pimaric-type acids have a methyl and vinyl group pendent from the same carbon atom. Figure 1 shows the stmcture of typical resin acids abietic acid, C2QH2QO2 (1) is predominant. The remaining 10% of commercial rosin consists of neutral materials that are either hydrocarbons or saponifiable esters. These materials are derived from resin acids by decarboxylation or esterification. 

The principal constituents of rosin (qv) are abietic and related acids. Tall oil (qv) is a mixture of unsaturated fatty and aHcycHc acids of the abietic family. Refined tall oil may be high in rosin acids or unsaturated acids, depending on the refining process. Ethoxylates of rosin acids, eg, dehydro abietic acid, are similar to fatty acid ethoxylates in surfactant properties and manufacture, except for thek stabiHty to hydrolysis. No noticeable decomposition is observed when a rosin ester of this type is boiled for 15 min in 10% sulfuric acid or 25% sodium hydroxide (90). Steric hindrance of the carboxylate group associated with the aHcycHc moiety has been suggested as the cause of this unexpectedly great hydrolytic stabiHty. 

Latex Types. Latexes are differentiated both by the nature of the coUoidal system and by the type of polymer present. Nearly aU of the coUoidal systems are similar to those used in the manufacture of dry types. That is, they are anionic and contain either a sodium or potassium salt of a rosin acid or derivative. In addition, they may also contain a strong acid soap to provide additional stabUity. Those having polymer soUds around 60% contain a very finely tuned soap system to avoid excessive emulsion viscosity during polymeri2ation (162—164). Du Pont also offers a carboxylated nonionic latex stabili2ed with poly(vinyl alcohol). This latex type is especiaUy resistant to flocculation by electrolytes, heat, and mechanical shear, surviving conditions which would easUy flocculate ionic latexes. The differences between anionic and nonionic latexes are outlined in Table 11. 

FIG. 12-98 Feed-type ring dryer. (Batr—Rosin)... 

This type of raw material can be chemically modified to make a variety of rosin derivatives having different degrees of compatibility and softening points. Common chemical reactions include ... 

Resins can be divided into natural and synthetic types. Natural resins have a vegetable or animal origin. Typical examples are rosins. Synthetic resins result from controlled chemical reactions, and can be divided into two subgroups. 

Extraction of rosin. Rosin resins are produced from three types of rosin, i.e. gum, tall oil, and wood. Extensive details about rosin resins extraction and derivatization can be found on page 269 in the book edited by Zinkel and Russell [18]. 

Chemistry of rosin. All three types of rosin consist primarily of C20 mono-carboxylic diterpene resin acids, the most common of which have the molecular formula C20H20O2. In addition, rosins contain small amounts of neutral and other acidic components (e.g. fatty acids in tall oil rosin). The neutral components of rosins are diterpene alcohols, hydrocarbons and aldehydes, and their contents generally vary between 5 and 15 wt%. 

The resin acids found in rosins are generally of the abietic- and pimaric-type. Rosins of various pine species differ in their content of abietic vs. pimaric-type acids. Rosins from species exhibiting high abietic-type acid compositions are preferred for production of rosin derivatives. However, the differences in properties of rosins are often associated with their non-resin acid content instead of their chemical compositions. On the other hand, the compositions of rosins from different sources greatly differ [22]. Table 8 shows a typical distribution of resin acids in rosins obtained from gum, tall oil and wood sources. 

On the other hand, not only initial colour but colour change (discolouration) of the resin under UV light and heat is important. Colour retention of a resin is related to the chemical stability and increases as the degree of non-aromatic conjugated unsaturation of the resin molecule decreases. Thus, for rosins a high level of abietic-type resin acids lead to relatively unstable resins. Hydrogenation and disproportionation as well as esterification provide improved stability and colour retention to rosins. 

The acid number is mainly defined for rosins and rosin-derived resins and for phenol-modified resins. Standard hydrocarbon resins have zero acid number because the absence of functional groups. However, the acid number allows one to control deterioration by oxidation with formation of carbonyl and carboxyl groups in hydrocarbon resins. Typical acid number values of different resin types are ... 

Triacetin resistance is especially critical when filter tips are made in one location, stored, and then shipped to another location. For these operations, polyethylene-based adhesives are used because of their low polarity and therefore excellent resistance to triacetin. Where filter plugs are attached at the same location shortly after production, EVA-based adhesives are suitable and preferred. Both types of adhesives use low odor, clean tackifiers such as hydrogenated hydrocarbons or pure monomer resins (typically a-methylstyrene based). Rosin, rosin esters, and phenol-containing tackifiers are not acceptable. EVA-based adhesives use a higher level of wax (about 1 /3 of the formula) than polyethylene-based adhesives (5-20% wax) due to the lower crystallinity and slower set of EVA vs. PE. Application viscosities are 2000-5000 cP. 

The theoretical minimum diameter particle to be separated in a cyclone of the basic type given by Figure 4-41 is given by the relation of Rosin [13]. 

Rosin. Rosin resin, also known as colophony, is collected from one of over 100 different types of trees that grow throughout Europe, Asia, North America, and New Zealand. The term colophony seems to derive from the ancient city of Colophon, in Lydia, which produced a high-quality resin. Rosin is drawn directly from living trees in a tapping process that entails inducing outflow of the resin from the trees. Rosin has been used as an adhesive and size and in the preparation of paints. 

Adsorption of e.g. rosin (abietic acid) at the pigment surface may - depending on the concentration of the rosin - reduce or accelerate the crystal growth. The presence of an excess amount of rosin during the production of diarylide yellow pigments of the Pigment Yellow 13 type affords an additional crystal modification, which can be identified by X-ray diffraction spectroscopy [4],... 

The specific influence of the rosin is suggested to happen due to an increased solubility of the sodium compound by micellization and to the formation of less stable mixed crystal-type lakes [2],... 

Equally important is the salt formation of solid bases with gaseous acids. An example has been cited above (30 31). This type of reaction is quite general. Strong and very weak bases react quantitatively and the gas-solid technique does not have problems with moisture. Amino acids such as L-phenylalanine, D-penicillamine (42), DL-penicillamine, L-cysteine, L-leucine, L-proline, DL-ty-rosine and others are quantitatively converted into their hydrohalides with... 

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