Maleic modified rosin

Maleic modified rosin is a commercial product and widely used as a binder in the printing ink industry. Levopimaric acid with its conjugated doubie bonds can undergo a Diels-Aider reaction with maleic anhydride, maleic acid or fumaric acid to produce maleic... 

Lewisol 28 [Aqualon]. TM for a pale, hard resin, a maleic-modified glycerol ester of rosin. Acid number 36, softening point 141C, USDA color WG. 

Chem. Descrip. Maleic-modified glycerol ester of rosin CAS 8050-31-5 EINECS/ELINCS 232-482-5 Uses Resin in lacquers, sealers, inks, grease-resistant coatings, specialty enamels... 

Chem. Descrip. Pentaerythrityl rosinate, maleic-modified CAS 8050-26-8 EINECS/ELINCS 232-479-9 Uses Resin in printing inks, varnishes... 

Modified rosins, however, are of greater importance now than the non-modified material. Typical modifications are hydrogenation-disproportionation, esterification, dimerization, and maleic/fumaric adducts. 

Rosin is commonly modified with maleic or fumaric acid to improve efficiency. Since the 1970s, dispersions of unsaponifted rosin have become more popular as a result of their improved sizing efficiency, lower alum requirements, and reduced pH sensitivity vs saponified rosins. Cationic dispersed rosin size, which can be effective at near-neutral and neutral papermaking conditions, is also available (63—65). Commercially available rosin sizes include Pexol, Neuphor, and Hi-pHase (Hercules Inc.), Plasmine and NeuRos (Plasmine), Stafor (Westvaco), Novaplus, and Novasize (Georgia Pacific), and NeuRos and Roscol (Akzo Nobel). 

For alkyd resins, non-benzenoid (maleic type) care must be taken to see that comparability is maintained over a period of years. Styrene alkyds are included in the total for some years. IMaleic alkyds, modified with rosin and rosin ester, are included in the annual figures and in the monthly figures. Figures on maleic alkyds are available from 1938 on 11),... 

Rosin Modifications. This class includes modifications with phenolics, phthalic alkyds, maleic alkyds, and fatty acids and oils. Rosin modifications can be broken out roughly into rosin and rosin esters, unmodified, and rosin and rosin esters, modified. The unmodified classification can be broken down into esters esterified with glycerol and esters esterified with other alcohols. The rosin and rosin esters, modified can then be broken down to those modified with phenolic and other tar acid condensates, those modified with phthalic alkyds, and those modified with maleic or fumaric alkyds. This is a very complicated classification and great care must be exercised in order to keep the classes consistent and comparable over a period of years. 

Perhaps one of the greatest changes in technology witnessed since the last edition is the decline in the use of anionic rosin size in Europe. Imparting hydrophobicity to paper by the use of rosin modified by maleic anhydride or fumaric acid and stabilised by casein at pH 4.5-5.0 is now seldom seen. 

Rosin is a non-reaclive prodnct and is retained on the anionic fibre by either attaching itself to a cationic source in the case of rosin soap, or anionic rosin emulsion or by having a cationic surface charge. The main requirement is that it requires a source of aluminium species to form the actual sizing agent, aluminium rosinate. Rosin is normally modified with maleic anhydride or fumaric acid to increase its reactivity with aluminium species and improve its efficiency at higher pH. The method by which this aluminium species is formed and retained in the wet-end of the paper/ board machine differs between anionic and cationic rosin sizes. 

Chem. Descrip. Modified maleic rosin resin Uses Maleic resin for coatings, inks (heat-set web offeet lithographic inks, sheet-fed quick-set lithographic inks)... 

Modified drying type phthalic alkyd Rosin modified maleic alkyd Modified maleic Chlorinated diphenyl... 

Alkyl-ary Isulfonamide-formaldehyde Vinylidenechloride-aerylooitrilecopolymers Hydrogenated rosin ester Rosin modified maleic alkyd Polyvinyl acetate... 

The most important rosin derivatives used in printing ink formulations are rosin oligomers and their esters, metal resinates, modified phenolic and alkyd resins, ester gums, maleic and fumaric acid adducts and their esters. Practically all types of printing inks can be manufactured with rosin-based components, because they provide good miscibility and compatibility with most film formers and other ink additives. 

In addition to the above-mentioned oils there are also several naturally-occurring and synthetic acids which are used for modifying purposes in the manufacture of alkyd resins. These include rosin (the main constituent of which is abietic acid (XIX)) and the adduct of rosin and maleic anhydride (XXI) in the formation of this adduct it is supposed that abietic acid isomerizes to the conjugated diene, levopimaric acid (XX), before addition occurs. The synthetic fatty acids pelargonic acid (XXII) and isooctanoic acid (XXIII) are also sometimes used as modifying acids in the preparation of alkyd resins. 

Rosins are used little as such but are widely used in chemically modified forms. Most of the modifications involve the carboxyl group or the double bonds and are effected by transformations such as hydrogenation, disproportionation (the process is, to a significant part, a dehydrogenation), esterification, polymerization, salt formation, or reaction with maleic anhydride or formaldehyde. 

Since Maly first esterified rosin in 1865, practically every conceivable ester of rosin has been prepared, including the glycerol ester, called ester gum, introduced in 1900 for lacquers and printing inks. The methyl ester of hydrogenated rosin is used as a plasticizer in lacquers. Pentaerythritol esters, unmodified and modified with maleic anhydride and phenol-formaldehyde, are used in varnishes. In 1937, the coatings industry used 20 million pounds of phenolic resins modified with ester gum in 1987,66 million pounds were used. Phenolic resins modified with up to 80% ester gum were called 4-hour enamels. Because these enamels possess excellent resistance to hot water and alkali, ester gum replaced damar, copal, and kauri gums in paints, lacquers, and enamels in combination with tung oil. 

Common resins in use are rosin esters, such as ester gum, which is used for its low cost maleic resin, used in wood finishes for its good sanding properties and alkyds, employed for their good resistance and durability. Alkyds modified with coconut oil are often used these may be ftirther modified with other resins, such as terpenes, for good heat-sealing properties and phenolics, for good water resistance. 

As a polymeric binder in liquid p., ->shellac was used, and rosin, modified with maleic acid, is (among many synthetic polymers) used today. 

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