New polymeric materials for paper and textiles conservation. II. Grafting polymerization of ethyl acrylate/methyl methacrylate copolymers onto linen and cotton

Abstract

In the preservation of Cultural Heritage items, the use of polymeric materials for the consolidation and protection of artifacts with historical and artistic value is widely accepted, except for cellulose-based materials, since here there are no suitable products and appropriate application techniques. Grafting polymerization of acrylic monomers onto cellulose chains represents an innovative method of restoration for both artificially and naturally aged textiles. In this article, some results concerning the grafting polymerization of ethyl acrylate/ethyl methacrylate 75/25 and ethyl acrylate/methyl methacrylate/trifluoroethyl methacrylate 73/24.5/2.5 polymers onto linen and cotton are reported. The effectiveness of grafting polymerization as a method for textiles conservation is discussed. The consolidating and protective effects were investigated by evaluating the mechanical properties and the wetting behavior of the grafted samples, and comparing them with the original and aged substrates.

Effects of artificial weathering on the mechanical properties of paper‐based materials consolidated with polymeric materials

“…The photoinitiated grafting reaction was carried out on Whatman paper previously oxidized with sodium metaperiodate to create photosensitive sites (aldehyde groups) on the cellulose; UV radiation transformed the carbonyl groups in the radical sites where the radical polymerization subsequently started. [4][5][6] Cellulose samples, after they were dried in an oven, were swollen in deionized water for 10 min to open up the fibrous structure of cellulose and encourage the homogeneous uptake of the monomers during grafting. Next, the wet samples were placed in a steel reaction vessel (volume ¼ 30 L), which was evacuated for a short time so that the paper was still damp; then, the liquid monomers mixture, 75/25 wt % EA/MMA, was loaded, vaporized, and diffused into the reactor.…”

“…Grafting directly from the vapor phase results in enhanced mechanical resistance of the degraded paper without the alteration of its typical flexibility, and importantly, no superficial coatings are formed on the grafted samples. 4,5 In this research, the grafting polymerization of an acrylic copolymer expressly tailored for cellulosebased materials, 75/25 wt % ethyl acrylate (EA)/ methyl methacrylate (MMA), was performed on different paper samples. In a previous article, we reported a complete study concerning the synthesis and characterization of the best acrylic copolymer to be used for the grafting process.…”

In Textiles

“…Graft polymerization of acrylic -based monomers onto a cellulose backbone has been studied as an innovative method for conservation of cellulosic textiles [14,15] . Grafting acrylate monomers directly from the vapor phase onto cellulose has been found to improve the mechanical properties of degraded textiles without altering the fl exibility and protects the surface from formation of superfi cial coating of other unwanted materials on storage.…”

“…The grafting of combination of monomers, e.g., ethyl acrylate (EA)/methyl methacrylate (MMA) in a ratio of 75/25 results in a restoration of fl exibility (t g ∼ 10 ° C). The addition of small quantity of the fl uorinated monomer 2,2,2 -tifl uoromethyl methacrylate (TFEMA) in the above combination, i.e., EA/MMA/TFEMA in the ratio of 73/24.5/2.5 is found to improve water repellency of the grafted substrate [15] .…”

Preparation and evaluation of composite microspheres of polyacrylamide‐grafted polysaccharides

“…Crosslinking between monomer units forms a unique 3D network (because of covalent bonding between monomers) that may give a strong mechanical strength . Grafting is the most extensively studied and applied way to impose one's polymer chains onto another's backbone; it involves the growth of grafts directly onto the polysaccharide backbone . The process involves free‐radical polymerization; these free radicals can be conveniently created along the polysaccharide backbone in the presence of radical or chemical initiators, γ rays, UV radiation, electron beams, and microwave irradiation…”