Degradability of poly(ether-urethanes) and poly(ether-urethane)/acrylic hybrids by bacterial consortia of soil

FACCIA, PAULA A.; PARDINI, FRANCISCO M.; AGNELLO, ANA CAROLINA; AMALVY, JAVIER I.; DEL PANNO, MARÍA T.

INTERNATIONAL BIODETERIORATION & BIODEGRADATION

ELSEVIER SCI LTD

Año: 2021 vol. 160

0964-8305

An enrichment culture strategy was used to obtain natural consortia from soil in order to study the biodegradabilityof poly(ether-urethanes) (PUE). PUE were synthesized with different aliphatic diisocyanate group,termed PUIPDI and PUHMDI. In addition, PUE/acrylic hybrids, termed PUH90:DEA10 and PUH70:DEA30 consistedof PUHMDI and increasing ratio of 2-(diethylamino)ethyl methacrylate (DEA) were tested. PUIPDI was biodeterioratedthrough urea-bond hydrolysis by a consortium dominated by Acinetobacter. A higher biodeteriorationrate was demonstrated for PUHMDI, which exhibited large surface holes and a greater weight loss. Thehydrolysis of ester-urethane bonds and the oxidation of soft-segment ether bonds were the key reactions identified,possibly by Acinetobacter, Mycobacterium, Sphingopyxis and Pseudomonas, which were present in thisconsortium. Diverse metabolic functions were also predicted. The addition of DEA favored the biodegradabilityof PUH:DEA hybrids demonstrated by the increased weight loss, swelling degree and the hydrolysis of DEA-esterbond. Urethane and ether bonds degradation were also detected. PUH:DEA hybrids selected even bacterialconsortia, most likely by allowing better access to the nutrients. Pseudomonadaceae and Bradyrhizobiaceae familiesgot relevance in these consortia and their outstanding features were cell mobility and quorum sensing. Thiswork has provided a deeper insight into PUE biodegradation by proposing the chemical mechanisms, bacterialtaxa and functions that could be implicated.