Rosin modified phenolic resin

Modified phenolic resins are condensation products of the resol type which contain other starting materials besides phenol and formaldehyde (e.g., acrylic monomers). The phenolic component itself is often modified (alkyl- or arylphenols). Modification with rosin is the most important one. The compatibility of phenolic resins with other binders can be substantially improved by modification. Rosin-modified phenolic resins may be combined with linseed oils and alkyd resins. Examples of use include putties, priming coats, rust protection paints, and colored topcoats. 

Only a limited amount of resin can be added to white paints due to its intrinsic color. Addition of these hard resins increases the hardness and the gloss of the paint films, accelerates and improves the drying of oxidatively cross-linking alkyd resins, and optimises sanding properties and corrosion protection in putties. Modified phenolic resins have lost much of their importance because they have been replaced by more efficient binder systems (e.g., thermoplastic and cross-linkable acrylic resins, polyurethane systems). Rosin-modified phenolic resins are, however, still extremely important in the production of resins for printing inks. 

Brown hard varnish n. Spirit varnish prepared from shellac dissolved in industrial alcohol. Cheaper grades may consist of shellac-rosin mixtures, spirit manila, spirit manila-rosin mixtures, or alcohol soluble rosin-modified phenolic resin. 

Rosin modified phenolic resin, another important rosin derivative used in the coating industry, is derived by reacting rosin with a resole type phenolic resin. The extent of modification, the type of phenolic resin used (in terms of the phenolic compound used), and... 

Rosin-modified phenolic resins are very useful in printing ink, oil lacquers, and in alkyd paint applications. A commonly used material consisting of rosin acids is colophonium that is ... 

Many resins are used in making oleoresinous varnishes. These include polyterpene resins, petroleum resins, coumarone-indene resins, gmn rosins, wood rosins, tall oil rosins, rosin soaps, rosin esters, novolac phenolic resins and rosin modified phenolic resins. 

The current practice is to classify as oil varnishes all varnishes and paint media prepared from drying oils and natural or preformed oil-free synthetic resins. Examples of such resins are rosin, rosin-modified phenolics and oil-soluble 100% phenolics. The introduction of the resin results in improved drying and film properties. 

If the para- substituent group R- (above) is an alkyl group of about four or more carbon atoms (e.g. tertiary butyl, (CH3)3 C-), the product is soluble in oils otherwise in alcohols, ether-alcohols or alcohol/aromatic hydrocarbon mixtures. If the resin is made from a phenol blocked in the para-position, with a high formaldehyde level and using an alkaline catalyst, it will react when heated with un-saturatcd materials, such as drying oils or rosin to produce a modified phenolic resin. The mechanism is thought to be of the type ... 

The reaction with rosin is used to modify phenolic resins and provides an alternative route to solubility in oils. The rosin carboxyl group is afterwards esterified with a polyhydric alcohol, such as pentaerythritol, to increase the resin molecular weight even further. 

Neither alcohol-soluble spirit Novolaks nor plasticized phenolic resins dissolve in dry-hardening oils such as linseed oil, however. The first step in this direction was achieved by the combination of phenolic resin with ester gum, i.e., abietic acid (the main component of colophonium or rosin) esterified with glycerine. These modified phenol resins or oleoresinous phenolics dry better than copal-linseed oil resins. Even better elasticized phenolic resins were developed by introducing new groups into the basic components. When bisphenol A (see Chapter 26) is used as a phenolic component, both the solubility in dry-hardening oils and the resistance to yellowing are improved. 

Bio-based composite materials were obtained by acid catalysed curing of ESO in the presence of terpene modified phenol-formaldehyde resin or rosin modified phenol-formaldehyde resin. These composites exhibited improved mechanical properties when compared with those of the ESO... 

Figure 4.11 Formation of rosin-modified phenol-formaldehyde resins.

Modified phenolic resins n. Resins in which the basic phenolaldehyde product has been modified by the introduction of rosin or other natural resin. The products are often esterified. 

The alkyd resins are of value because of their comparatively low cost, durability, flexibility, gloss retention and reasonable heat resistance. Alkyd resins modified with rosin, phenolic resin, epoxy resins and monomers such as styrene are of current commercial importance. 

Standard-grade PSAs are usually made from styrene-butadiene rubber (SBR), natural rubber, or blends thereof in solution. In addition to rubbers, polyacrylates, polymethylacrylates, polyfvinyl ethers), polychloroprene, and polyisobutenes are often components of the system ([198], pp. 25-39). These are often modified with phenolic resins, or resins based on rosin esters, coumarones, or hydrocarbons. Phenolic resins improve temperature resistance, solvent resistance, and cohesive strength of PSA ([196], pp. 276-278). Antioxidants and tackifiers are also essential components. Sometimes the tackifier will be a lower molecular weight component of the high polymer system. The phenolic resins may be standard resoles, alkyl phenolics, or terpene-phenolic systems ([198], pp. 25-39 and 80-81). Pressure-sensitive dispersions are normally comprised of special acrylic ester copolymers with resin modifiers. The high polymer base used determines adhesive and cohesive properties of the PSA. 

Chem. Descrip. Rosin/phenolic-modified alkyd resin in xyleneA/MP naphtha... 

Chem. Descrip. Rosin/phenolic-modified alkyd resin in xylene Uses Alkyd, modifier for coatings, vehicle refinish primers, air drying 1-part metal protective coatings... 

Polydipentene Sucrose acetate isobutyrate coatings modifier, pressure-sensitive Hydrogenated rosin coatings, /polymeric food-contact Aluminum stearates coatings, ablative Phenolic resin... 

Furfuryl alcohol phenolic resin comonomer Bisphenol A phenolic resin mfg. p-t-Amylphenol Tall oil rosin phenolic resin modifier Cumyl phenol Fumaric acid phenolic resins Phenol... 

On the other hand, vegetable or animal oils are othermodifiers in an alkyd formulation. Examples of vegetable oils are palm oil, palm kernel oil, soybean oil, olive oil, colza oil, sesame oil, wood oil, eastor oil, and linseed oil, whereas, animal oils are such as fish oil, whale oil, beef oil, mutton oil, and hoof oil. Natural resins such as rosin, amber, and shellac, and synthetic resins such as ester gum, phenol resin, carbon resin, and melamine resin, also have been reported as a modifier in the alkyd formulatioa... 

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. 

Cresylic acid, which is a mixture of cresols, phenol, and xylenols, is also used in resins. This material can be purchased from technical grades with 80-85 % of a particular constituent to 98% single component purity. A typical oil-soluble phenolic resin can be made from p-t-amylphenol employing an acid catalyst. Both p-r-butylphenol and p-r-octylphenol have applications here, too. If these materials are first reacted with an alkaline catalyst, then the initial resole formulation can be modified with unsaturated compounds such as drying oils, rosins, and rubber. 

A tackifier is a component to provide initial tackiness to adhesives. The compatibility of the tackifier to the main components is very important to increase the tackiness without degradation of the adhesive mixture. For that purpose, natural resins such as rosin and dammar, modified rosins such as coumarone-indene resin, polymerized rosin, hydrogenated rosin and rosin ester, and polyterpene resin are used. Recently, alkylphenol resins, terpene phenol resins, and xylene resins are out of use because of their hazardous nature inducing sick building syndrome. 

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