A Paula M Antunes

Use of aluminium alkoxide and oxazolidine II to treat acid-deteriorated historic leather

Abstract This study was undertaken to develop a product that will potentially delay the progress of deterioration of acid-deteriorated historic leather. Acid-deteriorated leather samples were treated with a new formulation consisting of aluminium di(isopropoxide) acetoacetate ester chelate (aluminium alkoxide) and 5-ethyl-1-aza-3,7-dioxabicyclo[3.3.0]octane (oxazolidine II). The leather samples were also treated with oxazolidine II and aluminium alkoxide separately to compare the effectiveness of these reagents against the new formulation. Untreated leather samples were used as a negative control. Acid-deteriorated leather samples treated with Cellugel®, aluminium alkoxide and the new formulation along with corresponding untreated leather samples were also subjected to accelerated ageing in order to investigate the longevity of the treated leather. The impact of the treatments and accelerated ageing was determined by measuring the hydrothermal stability of the leather and pH of the aqueous extract. The formulation showed a potential to provide the acid-deteriorated historic leather with long-term protection against an artificially-created acidic environment.

POROUS GELATIN SCAFFOLD MECHANICAL BEHAVIOUR UNDER CYCLIC LOAD AS A FUNCTION OF WATER CONTENT

Porous gelatin scaffolds have been extensively used for tissue engineering applications. The scaffolds primary role is to act as a means of delivery for seeded cells into the target tissue [Liu, 2009]. It should therefore provide a seeded cellular enclave with adequate mechanical support and suitable conditions for cellular proliferation. Depending on the target tissue, an implanted scaffold would face different loading patterns. Cyclic compressive load prevails within certain tissues such as knee cartilage. Due to their elastic nature, gelatin constructs may be considered a suitable candidate for these in vivo applications. However, due to excessive interaction between water and gelatin, characterising their mechanical properties in respect to structure water content is important. Gelatin is highly water absorbent, with the water acting as a plasticiser for gelatin molecules [Patil, 2000]. Higher water content reduces gelatin structural strength but increases its elasticity. In this study porous gelatin scaffolds were subjected to cyclic compressive loading at different water contents. Methods: