Characteristics of biodegradable poly(butylene succinate) nanocomposites with thermally reduced graphene nanosheets

Abstract

Poly(butylene succinate) (PBS) is a biodegradable aliphatic polyester and is semicrystalline in nature. It has a wide range of engineering applications owing to its attractive combination of good processability and mechanical properties. PBS nanocomposites with graphene nanosheets were prepared by melt compounding. We report on their structure and their thermal, electrical, and mechanical properties. The thermal stability of the nanocomposite increased by 358C compared with that of neat PBS. The crystallization and melting behavior of the PBS matrix in the presence of dispersed graphene nanosheets were studied by differential scanning calorimetry and polarised optical microscope. We also observed an interesting phenomenon in the PBS/graphene nanocomposites from our FTIR investigation. b-form of PBS crystals are formed in the composite samples with 5 wt% graphene loading, which otherwise forms in pure PBS only under stress. We observed 12% modulus enhancement for 2 wt% PBS/graphene nanocomposites. The electrical conductivity increased to 10 5 -fold for 5 wt% PBS/graphene nanocomposites. POLYM. COMPOS., 38:E42-E48, 2017.

Controlled‐release fertilizer based on poly(butylene succinate)/urea/clay and its effect on lettuce growth

“…The bands at 1321 and 2947 cm −1 are attributed to the symmetric and asymmetric deformational vibrations of the CH 2 groups in the main chain of PBS, respectively. The bands around 1152 and 1253 cm −1 correspond to stretching of the –COC– bonds in the ester group . The band at 1713 cm −1 is related to stretching vibrations of the ester group in PBS, specifically in the C=O bonds of the carbonyl.…”

Using an Ionic Liquid to Reduce the Electrical Percolation Threshold in Biobased Thermoplastic Polyurethane/Graphene Nanocomposites

“…Higher [1,50,51,52,53] p c values have been reported for melt-mixed NCs based on other polymer matrices and graphene. As in other NCs with carbonaceous nanofillers [54], the p c is affected by various factors including the aspect ratio, the degree of dispersion or orientation of the nanofiller, the processing method and parameters, and the viscosity, molecular weight, and crystallinity of the polymer matrix.…”

“…As can be seen in Figure 8a, a broad crystallization peak appeared on cooling at between 30 and 40 °C in the neat bTPU, indicating a broad distribution of the perfection/size of the crystals, which is attributed to the hard segments of the bTPU. In both the bTPU/GR and the bTPU/GR-IL NCs, the crystallization exotherms narrowed and shifted to higher temperatures (Table 3) as a result of the nucleating effect of the GR [1,51]. The increase was pronounced at low GR contents, but T c remained unchanged as greater amounts of GR were added.…”

“…The melting endotherms were narrower for the NCs and the main peaks appeared at the lowest values of the melting interval of the neat bTPU endotherm. This indicates a more homogeneous population of crystal sizes in the NCs [51] and a smaller mean size of the crystals. As previously proposed for the cooling curves, this is probably related to the nucleating effect of the GR on the crystallization of the bTPU.…”

“…With respect to the melting (Table 3) or crystallization (not shown) enthalpies, they hardly changed when the GR content changed. Different behaviors have been observed in the crystallinity of the polymer matrix of NCs when graphene is added: (i) increases in crystallinity resulting from a strong nucleation effect [1,40] (although the changes were not significant enough to affect the mechanical properties [57]); (ii) decreases in crystallinity as graphene acts as a physical barrier due to its large surface area and causes interference in the crystallization process [47,51,58]; and (iii) no change [59]. The behavior observed in Table 3 seems to indicate that even though GR favors the formation of bTPU crystal sites, the degree of crystallinity of the bTPU is unaffected by its presence.…”