Análise da degradação de amostras de papelexpostas a diferentes condições higrotérmicas

Abstract

In this study, paper samples were produced and naturally exposed to varying temperature and humidity conditions at two university libraries, located in Curitiba (910m a.m.s.l.) and in Caiobá, on the coast of Paraná state. The paper samples were produced with unloaded long-and short-fiber cellulose, without adhesives, in order to facilitate the analysis of the relationship between sample decay rate and natural ageing conditions at both libraries, relative to outdoors. The purpose of the research was to identify which climatic context presents the highest paper preservation potential, by means of the preventive conservation indices PI and TWPI (Preservation Index and the Time Weighted Preservation Index), which quantify the effects of temperature and humidity on paper life expectancy. The samples were placed in naturally ventilated acrylic containers covered with UV film, whose openings were protected with activated charcoal so that temperature and humidity had the major effects on the paper samples. For outdoors, Stevenson screens were used, wherein the acrylic containers were placed. Climatic data were recorded with data loggers and the paper samples were tested with regard to physical and chemical properties before and after a 12and 24 months natural exposure. Results indicate the largest decay rates for the samples with the shortest life expectancy according to PI/TWPI (obtained from ambient temperature and relative humidity) estimates.