Processing and Properties of PCL/Cotton Linter Compounds

Abstract

Biodegradable compounds of poly(ε-caprolactone) (PCL)/ cotton linter were melting mixed with filling content ranging from 1% to 5% w/w. Cotton linter is an important byproduct of textile industry; in this work it was used in raw state and after acid hydrolysis. According to the results of torque rheometry no decaying of viscosity took place during compounding, evidencing absence of breaking down in molecular weight. The thermal stability increased by 20% as observed in HDT for PCL/cotton nanolinter compounds. Adding cotton linter to PCL didn't change its crystalline character as showed by XRD; however an increase in degree of crystallinity was observed by means of DSC. From mechanical tests in tension was observed an increase in ductility of PCL, and from mechanical tests in flexion an increase in elastic modulus upon addition of cotton linter, whereas impact strength presented lower values for PCL/cotton linter and PCL/cotton nanolinter compounds. SEM images showed that PCL presents plastic fracture and cotton linter has an interlacing fibril structure with high L/D ratio, which are in agreement with matrix/fibril morphology observed for PCL/cotton linter compounds. PCL/cotton linter compounds made in this work cost less than neat PCL matrix and presented improved properties making feasible its commercial use.

Comparative Study of Polycaprolactone Electrospun Fibers and Casting Films Enriched with Carbon and Nitrogen Sources and Their Potential Use in Water Bioremediation

“…On the other hand, analyzing the DSC thermogram, similar thermal fluctuations can be seen [ 19 , 41 , 42 ], while previous studies shown a melting point of PCL around 60 °C [ 43 ], possibly indicating not only the melting of the material, but also the Cs present in the fibers, given the low temperatures at which these phenomena occur. The next relevant event in the thermogram arises at 360 °C, indicating the decomposition phase of the material, which has already been reported [ 44 ], reaching a peak in all samples at approximately 398 °C, with small variations between samples.…”

“…Thermal characterizations (TGA and DSC) were performed in this study, with the purpose of obtaining evidence of the presence of carbon and nitrogen sources on the PCL matrix by observing the mass degradation vs. temperature increment (TGA) and key temperature fluctuations (DSC) [ 19 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 ]. The calculated critical degradation temperature (TGA) is close to our reported decomposition temperature (DSC) of around ~380–390 °C.…”

Toughening of bio-PE upon addition of PCL and PEgAA

“…It was observed that addition of PCL to Bio-PE promoted a subtle decrease of HDT in binary blends, being a reduction of approximately 3.9% for the Bio-PE/PCL (90/10 w/w), 9.3% for the Bio-PE/PCL (80/20 w/w) and 12.6% for the Bio-PE/PCL (70/30 w/w). This decrease is probably due to the addition of PCL in the compound, since it presents high flexibility, due to its low melting temperature (≈60°C) and glass transition temperature (≈-60°C); that is, the presence of PCL promoted a softening effect in Bio-PE, making it more flexible and thus diminishing HDT (França et al, 2016;Morais, 2016;Bezerra et al, 2017b).…”

Jatobá wood flour: An alternative for the production of ecological and sustainable PCL biocomposites

“…In this case, the HDT results for the biocomposites are similar. Literature 41,42 has demonstrated that adding natural fibers in thermoplastic matrices increases HDT, due to the increase in the elastic modulus and the molecular mobility restriction.…”