Plastic toy soldiers, a lost battle? – an analytical perspective

António Pereira; António Candeias; Ana Cardoso; José Mirão; Ana Teresa Caldeira

doi:10.14568/cp2020002

Autores

António Pereira HERCULES Laboratory and CityUMacau Chair on Sustainable Heritage, Institute for Advanced Studies and Research of Évora University, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal; Chemistry Department, School of Sciences and Technology, Évora University, Rua Romão Ramalho 59, 7000-671, Évora, Portugal. https://orcid.org/0000-0002-9553-1618
António Candeias HERCULES Laboratory and CityUMacau Chair on Sustainable Heritage, Institute for Advanced Studies and Research of Évora University, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal; Chemistry Department, School of Sciences and Technology, Évora University, Rua Romão Ramalho 59, 7000-671, Évora, Portugal. https://orcid.org/0000-0002-4912-5061
Ana Cardoso HERCULES Laboratory and CityUMacau Chair on Sustainable Heritage, Institute for Advanced Studies and Research of Évora University, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal. https://orcid.org/0000-0002-4935-3398
José Mirão HERCULES Laboratory and CityUMacau Chair on Sustainable Heritage, Institute for Advanced Studies and Research of Évora University, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal. https://orcid.org/0000-0003-0103-3448
Ana Teresa Caldeira HERCULES Laboratory and CityUMacau Chair on Sustainable Heritage, Institute for Advanced Studies and Research of Évora University, Largo Marquês de Marialva 8, 7000-809 Évora, Portugal; Chemistry Department, School of Sciences and Technology, Évora University, Rua Romão Ramalho 59, 7000-671, Évora, Portugal. https://orcid.org/0000-0001-5409-6990

DOI:

https://doi.org/10.14568/cp2020002

Palavras-chave:

Artefactos plásticos, Estudo multi-analítico, Acetato de celulose, Fosfato de trifenilo, Ftalato de dimetilo

Resumo

A preservação e a conservação de coleções em museus requer o conhecimento dos seus materiais constituintes. O uso de variadas técnicas instrumentais pode fornecer resultados complementares sobre a composição e estrutura destes materiais. Um conjunto de soldadinhos de plástico (de meados do século XX) do Museu Militar do Porto apresentava um processo de deterioração acelerado. Para melhor compreender essa deterioração, os presentes autores utilizaram uma abordagem multi analítica. A micromorfologia dos objectos foi caracterizada através de microscopia estereoscópica e microscopia eletrónica de varrimento de pressão variável (VP-SEM-EDS), o polímero e seus aditivos foram identificados por espectroscopia de infravermelho com transformada de Fourier com reflexão total atenuada (ATR-FTIR) e ressonância magnética nuclear (1H e 13C RMN), respectivamente, e os produtos de degradação com estrutura cristalina foram identificados por microdifração de raios X (Micro-XRD). O polímero que contitui os soldadinhos foi identificado como acetato de celulose, tendo fosfato de trifenilo e ftalato de dimetilo como principais aditivos, e as eflorescências cristalinas foram idenficadas como fosfato de trifenilo. Esta metodologia mostrou-se adequada para uma caracterização detalhada de artefactos de plástico em ambiente museológico.

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