Soluble nylons

Polyamides (nylons) The main types of nylon are oil and petrol resistant, but on the other hand susceptible to high water absorption and to hydrolysis. There are a few solvents such as phenol, cresol and formic acid. Special grades include a water-soluble nylon, amorphous copolymers and low molecular weight grades used in conjunction with epoxide resins. Transparent amorphous polyamides are also now available. 

In the examples presented below, polymer-paper systems are examined for cases where there is complete impregnation of the substrate to form what behaves as a single component (poly(vinyl alcohol), soluble nylon, and Regnal) for cases where penetration is limited and the polymer and substrate behave in a generally separate manner (glues) and for cases where a range of behaviors—from apparent interactive to apparent independent—is observed although penetration is limited (poly-(vinyl acetates)). 

Chemistry, Physics, and Biology Laboratories. As a rule, before any artifact is subjected to treatment, the chemistry laboratory determines the causes of any alterations or deterioration. The nature and structure of the artifact, its pigments and inks, are identified to avoid negative reactions to prescribed treatment. Fixatives are recommended if required these may be cellulose acetate dissolved in acetone, soluble nylon, or acrylic resin sprays. Once stains are identified, several possible solvents are selected. For deacidification, either magnesium bicarbonate or barium hydroxide usually is recommended, depending on whether an aqueous or nonaqueous solution is called for. Bleaching is discouraged, but when necessary, hypochlorites are used with suitable antichlors. 

Soluble resins, such as nitrocellulose, caseins with caustic solvents, poly(vinyl acetate)s, soluble nylons, and polyacrylates. 

According to Grattan (9), the most common polymers used in solvent-resin consolidant systems are acrylics, poly(vinyl acetates), poly(vinyl butyrals), and soluble nylon. Of these, soluble nylon has since been shown to be unsuitable because it inevitably cross-links and embrittles within as little time as a few weeks (iO). The others are known to have excellent longterm stability (9). Most likely the stability of polymers placed inside the wood may be even better, because they would be protected from light-catalyzed degradation reactions. Possible wood-polymer interactions, however, are unknown at this time. 

Water-Soluble Starches, Gums, Cellulose Derivatives, and Synthetic Polymers. Water-soluble plant starches and gums have historically been used as glues and should be reversible. Some of the modern water-soluble polymers (e.g., cellulose ethers and esters and soluble nylon) should also be reversible. 

Candidates in the water-based group include the hot and liquid animal-hide glues, poly (vinyl acetate) emulsions (including the more reversible kids glue ) and other water-soluble natural or synthetic polymers (e.g., starches, natural gums, cellulose esters and ethers, soluble nylon). 

There exists a large number of other solvent-based adhesives derived from synthetic polymers that are soluble in organic solvents. For example, substituted nylons (aliphatic polyamides)—typically, N-methoxymethyl nylons—are soluble in some alcohols and alcoholic mixtures and have been used to provide solution adhesives with good rust resistance. Such soluble nylons may be compounded with many thermosetting polymers to improve their properties to yield such outstanding characteristics as their resilience and peel strength. 

In most widely used two-polymer adhesives, the thermosetting component is phenolic. Phenolic resins are generally compatible, although not easily miscible, with a number of thermoplastic polymers. Particularly good compatibility is demonstrated between conventional alcohol-soluble phenolic resins and polyvinyl esters and acetals. Epoxies are important in two polymer adhesive systems. The most important thermoplastic components are the polyvinyl acetals (polyvinyl formal and butyral) and synthetic rubber, particularly nitrile rubber. Soluble nylons are also an important class. ... 

Nylon-epoxy Soluble nylon Liquid epoxy DICY-type No... 

Qu, L.W. Veca, L.M. Lin, Y. Kitaygorodskiy, A. Chen, B.L. McCall, A.M. Connell, J.W. Sim, Y.P. (2005). Soluble Nylon-Functionalized Carbon Nanotubes from Anionic Ring-Ofjening Polymerization from Nanotube Surface. Macromolecules, 38, 10328-10331. 

Sease, C. (1981). The case against using soluble nylon in conservation work. Studies in Conservation, 26(3), 102-110. 

Many polymers are used in contact with water. The conditions may be made more extreme by heating the water (but see above), by changing the pH or dissolved salts, or by using alternating wet/dry periods. Polymers that react with water, often by hydrolysis, will be sensitive to changes in pH. A notable example reported in conservation is the cross-linking of soluble nylon in even mildly acidic conditions (Bockhoff et al., 1984). 

De Witte, E. (1975). Soluble nylon as consolidation agent for stone. Studies in Conservation, 20(1), 30-34. 

Qu, L., et al. Soluble nylon-functionalized carbon nanotubes from anionic ring-opening polymerization from nanotube surface. Macromo g i[ g 2005,35(24), 10328-10331. 

Polyesters Silicones Furanes Acrylics Soluble nylons... 

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