Innovative microcrystalline cellulose composites as lining adhesives for canvas

Thin adhesive composite films were prepared by meltcompounding and compression molding of a thermoplastic resin (ParaloidVR B72) widely used for art protection and restoration with a microcrystalline cellulose powder (MCC). To simulate an oil painting restoration work, MCC-based composites were applied as lining adhesives on two kinds of canvases (English linen and woven polyester). Interestingly, single–lap shear tests both in quasi-static and creep conditions showed a remarkable stabilizing effect provided by MCC addition. Post-mortem microstructural analysis of the overlap adhesive area proved how MCC introduction did not change the fracture behavior of the bonded joints. The visual assessment of transparency and color measurements evidenced a chromatic variation of MCC-based films with a filler amount of 30 wt%, while, UV-vis analysis showed a decrease of relative transmittance in proportion to the MCC content. Additionally, rheological tests highlighted a viscosity increase for Paraloid B72 in both dry and wet conditions (T523C and RH5of 55%) as the MCC content increases. © 2015 Society of Plastics Engineers