Biodegradable composites based on well-characterized cellulose and poly (butyleneadipate-co-terephthalate)

As a biodegradable and flexible copolymer, poly(butyleneadipate-co-terephthalate) (PBAT) is used for packaging. However, high cost and limited properties restrict its applications. Because of the hydrophobic nature of PBAT, low mechanical properties are observed when PBAT and cellulosic fibers, which are hydrophilic, are used in blends. To increase the interfacial adhesion between cellulose and PBAT, γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH560) was used as a reactive compatibilizer to modify cellulose. A one-step method was demonstrated for compounding and subsequent extrusion blowing, which is a simple and environmentally friendly approach to fabricate a series of K-Cellulose/PBAT (KH560-Cellulose/PBAT) composites. The morphology and structure of the cellulose were characterized by scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectrophotometry. Meanwhile, thermal analysis of the hybrids showed an improvement of the thermal stability of the composites with increased silanized cellulose content. In addition, the barrier properties of films are measured by water vapor permeability (WVP) and oxygen permeability (OP). Finally, after addition of reactive compatibilizer KH560, there was considerable improvement with increased the cellulose content, as shown through mechanical properties testing. Therefore, the composites prepared with these enhanced properties have great potential as substitutes for traditional commodity polymers.