Study of Aliphatic-Aromatic Copolyester Degradation in Sandy Soil and Its Ecotoxicological Impact

Abstract

Degradation of poly[(1,4-butylene terephthalate)-co-(1,4-butylene adipate)] (Ecoflex, BTA) monofilaments (rods) in standardized sandy soil was investigated. Changes in the microstructure and chemical composition distribution of the degraded BTA samples were evaluated and changes in the pH and salinity of postdegradation soil, as well as the soil phytotoxicity impact of the degradation products, are reported. A macroscopic and microscopic evaluation of the surface of BTA rod samples after specified periods of incubation in standardized soil indicated erosion of the surface of BTA rods starting from the fourth month of their incubation, with almost total disintegration of the incubated BTA material observed after 22 months. However, the weight loss after this period of time was about 50% and only a minor change in the M(w) of the investigated BTA samples was observed, along with a slight increase in the dispersity (from an initial 2.75 up to 4.00 after 22 months of sample incubation). The multidetector SEC and ESI-MS analysis indicated retention of aromatic chain fragments in the low molar mass fraction of the incubated sample. Phytotoxicity studies revealed no visible damage, such as necrosis and chlorosis, or other inhibitory effects, in the following plants: radish, cres, and monocotyledonous oat, indicating that the degradation products of the investigated BTA copolyester are harmless to the tested plants.

LC-Multistage Mass Spectrometry for the Characterization of Poly(Butylene Adipate-co-Butylene Terephthalate) Copolyester

“…The biodegradability has been intensively evaluated by many authors [2-4, 7, 8]. The thermal properties of the polymer composition have been studied by means of DSC [5], and the general structures and composition information have been investigated by using NMR and GC-MS [8][9][10]. Many researchers [6,[11][12][13] have also demonstrated that the copolyester structure (random or block) can be investigated using multistage mass spectrometry (MS n ) with various soft ionization techniques.…”

Clay Nano-Biocomposites Based on PBAT Aromatic Copolyesters

“…Ecotoxicity tests based on plants growth (such as oat, cress, radish, etc.) also demonstrated that degradation products are totally harmless to the tested plants [7]. Meeting the requirements, Ecoflex has thus been certified as compostable material.…”

Effect of composting plant material with copolyester on quality of organic matter

“…The highest C ha concentrations were assessed in alkaline extracts obtained from composts without nonwoven fabric supplement (K0). On the other hand, Richter et al [16] report enzymatic character of BTA degradation with a small share of hydrolysis processes and the fact that the higher the share of aromatic rings, the more difficult the microbial decomposition [4].…”

“…The type of organic matter used for the composting process, the quantity and kind of added polymer material also have an influence on these properties. It is important because the biodegradation process of some plastics is much faster in the "natural" environment than in simulated laboratory conditions [8] and it does not show an ecotoxic effect [16][17][18]. Humification process which occurred in the materials composted with a small amount of biodegradable materials is progressing similarly as humification process of organic matter supplied to the soil with organic fertilizers or other organic materials [19].…”