Impact of black yeasts on the durability of polyurethane foam in tropical conditions in Vietnam

Hoai Nguyen Thu,V.N Sereda,Cuong Ngo Cao,Thinh Do Tat,Hong Do Thi Thu

doi:10.1051/e3sconf/202016902007

Abstract

Polyurethane (PU) is a material that is widely used in industries. However, tropical climatic conditions in Vietnam often make the durability of PU lower than temperate climatic conditions. One of the causes of this problem is the biodegradation of microorganisms. In this study, biological characteristics of black yeast on PU is evaluated, thereby, initially assessing the impact of black yeast on the durability of PU in tropical conditions. Ten strains of black yeast were isolated from used PU foam samples in Vietnam. These black yeast strains were tested for enzyme activity including: urease activity, protease activity, polyurethanase activity. There were two strains selected to identify based on sequence analysis of the ITS1/ITS2 region, they belong to genusAureobasidium. VN1Y3 was strain selected for biodegradability testing of PU foam samples. After 28 days of testing, the PU foam samples that have been infected with black yeasts have a change compared to the control in terms of color, surface, tensile strength, elongation. Research results have showed the impact of black yeast on the durability of PU.

Highlights

Polyurethane (PU) is a synthetic polymer that is formed by condensation polymerization reaction between polyisocyanate and polyol having intramolecular urethane bonds
Ten black yeast strains were isolated from used PU foam sample in Vietnam (Table 1)
After 28 days of testing with strain VN1Y3, PU foam samples were changed in color, surface, tensile strength and elongation compared to the control PU foam

Summary

Introduction

Polyurethane (PU) is a synthetic polymer that is formed by condensation polymerization reaction between polyisocyanate and polyol having intramolecular urethane bonds. Biodegradation is a chemical degradation of polymers by the action of microorganisms, such as bacteria, yeasts and fungi. Microorganisms degrade the polymers like polyurethane by using it as a substrate for their growth. Crabbe et al found four species of fungi including Curvularia senegalensis, Fusarium solani, Aureobasidium pullulans, and Cladosporium sp. They were isolated based on their ability to utilize a colloidal polyester PU (Impranil DLNTM) as the sole carbon and energy source [2]. All species were capable of utilizing the polyurethane paint as a sole carbon and energy source with the exception of P. cepacia [3].

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Results

Conclusion