resumo
In this work bleached E. globulus kraft pulp was doped with polyhexamethylene biguanide (PHMB) from an aqueous solution or from a suspension of silica capsules (PHMB@silica) by impregnation under atmospheric or ultra-high pressure (UHP) conditions (500 MPa). The antimicrobial properties of pulps were evaluated towards gram-negative E. coli and gram-positive L. innocua bacteria. PHMB loads below 500 mg per kg of pulp revealed negligible bacteriostatic properties, whereas PHMB loads of ca 3000-4000 mg per kg demonstrated bactericidal properties of pulp without significant deterioration of its mechanical strength. The UHP impregnation allowed significant improvement of PHMB uptake. Thus, under equal conditions, PHMB uptake was ca 25% greater under UHP than under atmospheric pressure impregnation, whereas the leachable amounts of PHMB in both pulps were comparable. The sorption of PHMB@silica on pulp in suspension under UHP conditions was ca 17% greater than under atmospheric pressure with almost 70% increase of leachable PHMB. (C) 2017 Elsevier Ltd. All rights reserved.
palavras-chave
POLYHEXAMETHYLENE BIGUANIDES; PHOSPHOLIPID-MEMBRANES; ESCHERICHIA-COLI; FOODS; BIOCIDE; STARCH; OPPORTUNITIES; POLIHEXANIDE; CHALLENGES; TEXTILES
categoria
Chemistry; Polymer Science
autores
Salgueiro, AM; Santos, MD; Saraiva, JA; Almeida, F; Sousa, I; Tedim, J; Nogueira, HIS; Evtuguin, DV
nossos autores
Ana Margarida Martins Salgueiro Carta
Estudante de doutoramento
Dmitry Evtyugin
Professor Associado com Agregação
Helena Isabel Seguro Nogueira
Professor Auxiliar com Agregação
Isabel Cristina de Sá Correia de Sousa
Investigador Júnior
João Tedim
Professor associado
Mauro Santos
Bolseiro de investigaçãoGrupos
G1 - Materiais Porosos e Nanossistemas
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
G4 - Materiais Renováveis e Economia Circular
agradecimentos
The authors acknowledge Fundacao para a Ciencia e Tecnologia (FCT) and Renova FPA, SA for PhD grant SFRH/BDE/51855/2012. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. The authors would also like to acknowledge FCT/MEC for the financial support to QOPNA research Unit (FCT UID/QUI/00062/2013), through national funds and where applicable co-financed by the FEDER, within the PT2020 Partnership Agreement. Joao Tedim thanks FCT for the researcher grant IF/00347/2013. Finally, authors thank Renova FPA, S.A. for supplying materials and technical facilities.