Dependency of tensile properties and biodegradation on molecular mass during hydrolysis of poly(butylene succinate)

The molecular mass of biodegradable polymers often explains the varying biodegradation results in outdoor environments and determines the mechanical properties and embrittlement of polymer samples. Accordingly, we have investigated the relationship between the molecular mass of poly(butylene succinate) (PBS) and its tensile properties and mineralisation. With decreasing molecular mass, we found that Young’s modulus was rising while tensile strength and elongation at break were decreasing. A ductile-brittle transition was found between a Mw of 80,000 g/mol and 110,000 g/mol. The dependency of mechanical properties on molecular mass as determined after hydrolysis differed significantly from a study performed on freshly synthesised PBS. Biodegradation to CO2 by microorganisms in a mixture of field soil and compost soil was found to begin at a Mw between 8060 g/mol and 26,666 g/mol. These results are essential for estimating the service life of products made from PBS.