Effect of processing additives on (bio)degradability of film-blown poly(?-caprolactone)

Abstract

Poly(-caprolactone)s (PCL) with slip masterbatch, Erucamide, SiO 2 and Erucamide ϩ CaCO 3 as low-molecular-weight processing additives, were film-blown in a single screw extruder. The films and recycled PCL without additives were exposed to composting, anaerobic sewage sludge (37 and 55°C), pure fungal culture, and chemical hydrolysis at two pH (7 and 10.5) and at two temperatures (room temperature and 50°C). Recycling and addition of processing additives resulted in a slightly slower degradation rate compared with the degradation of pure PCL. The degradations in biotic environment were generally faster than in abiotic environment. Higher degradation rates are observed in more complex environments (composts and anerobic sewage sludge) due to synergism between high temperature and a richer fauna of microorganisms. In the biotic environments, faster reductions in number-average molecular weight (M n ) than in weight-average molecular weight (M w ) were observed. A decrease of M n with up to 75-80% was estimated for composted pure PCL, while similar samples in anaerobic sludge at 55°C were completely degraded in 50 days. The mechanical properties of the samples subjected to composting exhibited a more rapid enbrittlement compared to the samples subjected to abiotic hydrolysis. The observed increase in crystallinity with increasing degree of degradation is explained by crystallization made possible by chain cleavage in the amorphous phase.

Hydrolytic Degradation of Porous Crosslinked Poly(ε-Caprolactone) Synthesized by High Internal Phase Emulsion Templating

“…There are several ways to tune the degradation rate by tailoring the chemical configuration, molecular weight and macroscopic design, see Figure 5 for a graphical illustration of some of the established governing factors for hydrolytic degradation process. Temperature is known to have significant effect on the rate of hydrolytic degradation [ 12 , 44 , 45 ]. Here two different aging temperatures, 37 °C and 60 °C, were utilized.…”

Polycaprolactone/modified bagasse whisker nanocomposites with improved moisture‐barrier and biodegradability properties

“…PCL is a degradable polymer in different biologically active environments, including rivers, soil sewage sludge, and compost. [12][13][14][15] It has a high molecular weight and crystallinity, which affect its biodegradability. 16 It has been reported that esterase and other kinds of lipase can degrade poly(e-caprolactone) by hydrolysis.…”

PY-GC/MS an effective technique to characterizing of degradation mechanism of poly (L-lactide) in the different environment

“…The apparent increase in polydispersity (to 3.86) for the biotic sample indicated that cleavage occurs mainly at the chain ends. 20,21 In the case of the abiotic samples, degradation occurred mainly randomly because the polydispersity remained closer to 2. Figure 6 shows the FTIR spectrum of the unaged sample and of samples after 11 weeks in the biotic and abiotic media.…”

“…On the other hand, in biotic media, extracellular enzymes from micro-organisms attack the surface of the polymer and this results in surface erosion. [21][22][23][24] This can also partly prevent the water molecules from penetrating into the inner part of the sample, and the hydrolysis of the inner part of biotic samples thus occurs more slowly than the hydrolysis of the inner part of abiotic samples.…”