Ketone resins

A varnish is often appHed on top of the paint layers. A varnish serves two purposes as a protective coating and also for an optical effect that enriches the colors of the painting. A traditional varnish consists of a natural plant resin dissolved or fused in a Hquid for appHcation to the surface (see Resins, natural). There are two types of varnish resins hard ones, the most important of which is copal, and soft ones, notably dammar and mastic. The hard resins are fossil, and to convert these to a fluid state, they are fused in oil at high temperature. The soft resins dissolve in organic solvents, eg, turpentine. The natural resin varnishes discolor over time and also become less soluble, making removal in case of failure more difficult (see Paint and FINNISH removers). Thus the use of more stable synthetic resins, such as certain methacrylates and cycHc ketone resins, has become quite common, especially in conservation practice. 

Ketonic resins (Laropal K 80 , MS2A) -1930 Varnishes Seed oils Quite stable with ageing with a low tendency to yellowing... 

Figure 5.19 GALDI mass spectra of (a) Ketone Resin N (from THF solution) and (b) ketone resin varnish from a painting (from THF solution). The signal groups generally correspond to cyclohexanone units...

The varnish on a modern painting ( Mont Saleve by Alexandre Perrier, 1916, private collection) showed a mass spectrum (Figure 5.19b) almost identical to that of Ketone Resin N. The use of a cyclohexanone resin as a picture varnish seems uncommon because copolymers such as AW2 were preferred by conservators [62]. An investigation into cyclohexanone resins by direct temperature-resolved MS (DTMS) is reported in the literature [22, 64]. Similar mass spectrometric patterns were achieved with masses accurately reflecting the values expected for the oligomers. 

H. Mestdagh, C. Rolando, M. Sablier and J. P. Rioux, Characterization of ketone resins by pyrolysis gas chromatography/mass spectrometry, Anal. Chem., 64, 2221 2226 (1992). 

The ketone resin (loading 1.88 mmol g based on C=0) was recovered. 

Preparation of the resin-hound cyclic malonic ester (638) (Scheme 133) A solution ofmalonic acid (38 mmol), concentrated sulfuric acid (0.1 mL), and acetic anhydride (117 mmol) was allowed to stand for 24 h at r. t. and was then concentrated in vacuo below 40 °C. The ketone resin (2 g) was pre-swollen in dry, cooled to 0 °C, and then added to the residue. Dry CH2CI2 (2 mL) was then added to the mixture, and it was stirred below 20 °C for 24 h. The resin was then washed as follows ... 

Primers, sometimes called self-adhesive resins or adhesion promoters, can be used to improve adhesion, for instance Self-Adhesive Resin EP 2440, Hills AG, Marl. The resin is soluble in many different solvents and can thus be readily applied before the adhesive. It is also used as an adhesion promoter for polyester and ketone resins. Other adhesion promoters include 0.5% silanes in methanolic solution. They are mixed directly into the adhesives or applied to the adhesion smfaces. 

Laropal . [BASF AG] Aldehyde and ketone resins lightfast resins for surface coatings, pigment pastes, flexo-gnq)hic and gravure inks. 

To determine the degree of acylation of polymers, heat 500 mg ketone resin, 500 mg hydroxylamine HCl, and 2 mL pyridine overnight at 105°C in a closed tube. Collect the resin on a fritted filter wash successively with DCM, ethanol, water, ethanol, methanol, and DCM and dry. The IR spectrum should show complete loss of the C=0 band. Combustion analysis for N gives the degree of acylation. 

Open-pore wood varnish DBP/blown castor oil (0.5 1), melamine resin, dammar or ketone resin NC PL resin = 1 0.5 1... 

The neutral behavior of poly(vinyl acetate) allows the use of all conventional pigments. Poly(vinyl acetate) is highly compatible with ester-soluble nitrocellulose and improves the adhesion and lightfastness of the latter. Poly(vinyl acetate) can also be readily combined with phenolic resins, ketone resins, and colophony resins. 

Diacetone alcohol [123-42-2] (4-hydroxy-4-methyl-2-pentanone) is an almost odorless ketone alcohol that is weakly acidic as a result of rearrangement to the enol form. It is miscible with water and organic solvents except aliphatic hydrocarbons. It acts as a good solvent for cellulose esters and ethers, alcohol-soluble resins, castor oil, and plasticizers. Poly(vinyl acetate) and chlorinated rubber are partially dissolved or swollen. Polystyrene, poly(vinyl chloride), vinyl chloride copolymers, dam-ar resins, resin esters, rubber, bitumen, mineral oils, ketone resins, and maleate resins are insoluble. Diacetone alcohol is used as a high boiler in stoving enamels to improve flow and gloss. 

Methyl acetate [79-20-9] is partially miscible with water and readily miscible with most organic solvents. It has a good solvency for cellulose esters and ethers, colophony, urea, melamine-, and phenol-formaldehyde resins, poly(vinyl acetate), alkyd resins, ketone resins, and other resins. It does not dissolve shellac, damar resin. 

Ethyl triglycol [112-50-5] [2-(2-ethoxyethoxy)ethoxy]ethanol, triethylene glycol monoethyl ether] is an almost colorless, neutral, mild-smelling liquid with a low hygroscopicity. It is soluble in water and most organic solvents, but is only partially miscible with aromatic and aliphatic hydrocarbons. Ethyl triglycol dissolves cellulose nitrate, shellac, colophony, ketone resins, maleate resins, chlorinated rubber, alkyd resins, and many other paint resins. It does not dissolve cellulose acetate, poly(vinyl chloride), vinyl chloride copolymers, fats, oils, and rubber. 

Methoxybutanol [30677-36-2] (3-methoxy-l-butanol) is a mild-smelling liquid that is miscible with water and organic solvents. It has a good solvency for cellulose nitrate, cellulose esters, poly(vinyl butyral), ketone resins, phenol-, urea-, and... 

N.N-Dimethylformamide [68-12-2] (DMF) [14.276] is miscible with water and organic solvents except aliphatic hydrocarbons. It is a good high-boiling solvent for cellulose esters, cellulose ethers, poly(vinyl chloride), vinyl chloride copolymers, poly(vinyl acetate), polyacrylonitrile, polystyrene, chlorinated rubber, polyacrylates, ketone resins, and phenolic resins. Alkyd resins and resin esters are partially soluble. Dimethylformamide does not dissolve polyethylene, polypropylene, urea-formaldehyde resins, rubber, and polyamides. It is used as a solvent in printing inks, for polyacrylonitrile spinning solutions [14.277], and as a solvent in the synthesis of acetylene. 

Chem. Descrip. Eightfast aldehyde and ketone resins Uses Resin for surface coatings, prod, of pigment pastes forflexographic and gravure inks... 

Uses Binder for fast-drying anticorrosion coatings combination binder for alkyd resins, acrylates, and ketone resins, improving initial adhesion and water repellency... 

Synthetic adhesives and acrylic paints are but two examples of synthetic polymers widely used in art and conservation. However, these products generally were not specifically developed for conservation purposes, and most manufacmrers, citing trade secrets, refuse to reveal the precise contents of their products. This is especially true of such additives as antioxidants, flocculants, antifoamers, emulsifiers, etc. Often companies have changed the contents of products, keeping the same name while not informing the customers about these changes. A weU-known example is that of ketone resin varnishes. An extensive review of the thermal analysis of polymers is given in Chapters 4 and 5 of this book. Here we note a few of the applications of pyrolysis in the area of art and conservation. 

Trade Name Synonyms Aztec CHP-50-P1 T[Aztec Peroxides] Aztec CHP-90-W1 T[Aztec Peroxides] Aztec CHP-HA-1 T[Aztec Peroxides] Cyclonox BT-50 T[Akzo Nobel http //www.akzonobel.com]] Luperox K4CE [At ofi n a http //www. atofinachemicals. com] Perhexa H j[NOF http //www.nof.co.jp] Cyclohexanone resin Synonyms Ketone resin Properties Colorless to pale yel. solid sol. in oxygenated solvs. insol. in aliphatic solvs. and water acid no. 0 hyd. no. 0 Uses Adhesion promoter in printing inks modifier for clear metal cellulose lacquers tackifier for polyamide hot-melt adhesives in food-pkg. adhesives floor paints Regulatory FDA 21CFR 175.105... 

Ketone methyl phenyl. See Acetophenone Ketone moschus. See Musk ketone Ketone, phenyl 2-pyridyl. See 2-Benzoyl pyridine Ketone, phenyl 4-pyridyl. See 4-Benzoyl pyridine Ketone propane. See Acetone Ketone resin. See Cyclohexanone resin Ketopentamethylene. See Cyclopentanone... 

Polyarylene ether ketone. See Polyether ketone Polyarylether ketone resin CAS 55088-54-5 60015-05-6 Synonyms PAEK PEKEKK Poly (1,4-benzenedicarbonyl-alt-bis (4-phenoxyphenyl) methanone) Poly ether ketone ether ketone ketone Poly (oxy-1,4-phenylenecarbonyl-1,4-phenyleneoxy-1,4-phenylenecarbonyl-1,4-phenylenecarbonyl-1,4-phenylene) resin Classification Polymer... 

Poly ether ketone ether ketone ketone. See Polyarylether ketone resin... 

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