The aim of this study was to gain a better understanding of the crystallization behavior of triethyl-citrate-plasticized poly(lactic acid) (PLA-TEC) in the presence of chitin nanocrystals (ChNCs). The isothermal crystallization behavior of PLA-TEC was studied by polarized optical microscopy, scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction (XRD). Interestingly, the addition of just 1 wt % ChNCs in PLA-TEC increased the crystallization rate in the temperature range of 135-125 C. The microscopy studies confirmed the presence of at least three distinct types of spherulites: negative, neutral, and ring banded. The ChNCs also increased the degree of crystallinity up to 32%, even at a fast cooling rate of 25 C min −1 . The XRD studies further revealed the nucleation effect induced by the addition of ChNCs and thus explained the faster crystallization rate. To conclude, the addition of a small amount (1 wt %) of ChNC to plasticized PLA significantly affected its nucleation, crystal size, and crystallization speed; therefore, the proposed route can be considered suitable for improving the crystallization behavior of PLA.

A series of novel naphthophenanthridine derivatives are synthesized via N-annulation of hexabutoxytriphenylene-1amine with various aliphatic aldehydes through the Pictet− Spengler reaction. The synthesized derivatives have been found to self-assemble into a columnar hexagonal mesophase over a wide temperature range, as validated through polarized optical microscopy, differential scanning calorimetry and X-ray diffraction experiments. The photophysical properties of these compounds were studied using UV−visible and emission spectroscopy. The synthesized compounds exhibit ambipolar charge transport, showing temperature-independent electron and hole mobility on the order of 3 × 10 −4 cm 2 /V s, as evaluated by the time-of-flight technique. These novel N-annulated derivatives can be of immense potential toward semiconducting applications of self-assembling supramolecular systems.

The crystalline phase of poly(lactic acid) (PLA) has crucial effects on its own properties and nanocomposites. In this study, the isothermal crystallization of PLA, triethyl citrate-plasticized PLA (PLA–TEC), and its nanocomposite with chitin nanocrystals (PLA–TEC–ChNC) at different temperatures and times was investigated, and the resulting properties of the materials were characterized. Both PLA and PLA–TEC showed extremely low crystallinity at isothermal temperatures of 135, 130, 125 °C and times of 5 or 15 min. In contrast, the addition of 1 wt % of ChNCs significantly improved the crystallinity of PLA under the same conditions owing to the nucleation effect of the ChNCs. The samples were also crystallized at 110 °C to reach their maximal crystallinity, and PLA–TEC–ChNC achieved 48% crystallinity within 5 min, while PLA and PLA–TEC required 40 min to reach a similar level. Moreover, X-ray diffraction analysis showed that the addition of ChNCs resulted in smaller crystallite sizes, which further influenced the barrier properties and hydrolytic degradation of the PLA. The nanocomposites had considerably lower barrier properties and underwent faster degradation compared to PLA–TEC110. These results confirm that the addition of ChNCs in PLA leads to promising properties for packaging applications.

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In this review, we summaries the past few year work on the chemistry of CWA's and their simulants on various heterogeneous surfaces of zeolites, composites of zeolites and doped zeolite with transition metal oxides. This review elaborates an updated literature overview on the degradation of CWA's and its simulants. The data written in this review were collected from the peer-reviewed national and international literature.

The orientation of polymer composites is one way to increase the mechanical properties of the material in a desired direction. In this study, the aim was to orient chitin nanocrystal (ChNC)-reinforced poly(lactic acid) (PLA) nanocomposites by combining two techniques: calendering and solid-state drawing. The effect of orientation on thermal properties, crystallinity, degree of orientation, mechanical properties and microstructure was studied. The orientation affected the thermal and structural behavior of the nanocomposites. The degree of crystallinity increased from 8% for the isotropic compression-molded films to 53% for the nanocomposites drawn with the highest draw ratio. The wide-angle X-ray scattering results confirmed an orientation factor of 0.9 for the solid-state drawn nanocomposites. The mechanical properties of the oriented nanocomposite films were significantly improved by the orientation, and the pre-orientation achieved by film calendering showed very positive effects on solid-state drawn nanocomposites: The highest mechanical properties were achieved for pre-oriented nanocomposites. The stiffness increased from 2.3 to 4 GPa, the strength from 37 to 170 MPa, the elongation at break from 3 to 75%, and the work of fracture from 1 to 96 MJ/m3. This study demonstrates that the pre-orientation has positive effect on the orientation of the nanocomposites structure and that it is an extremely efficient means to produce films with high strength and toughness.

Rapidly growth of Indian aluminum industry generates the significant amount of solid waste. Red mud is major solid waste generate from aluminum industry. Red mud contains some toxic elements, dumping of red mud contaminates the soil and water and also covers the valuable land. Geo polymerization technique could be the promising future for disposal of red mud. Geo polymerization leads to convert red mud into cost-effective binders in presence of alkali media, which demonstrates better mechanical and durability properties than conventional binders. The present study recaps the studies on geo polymerization of red mud produce from aluminum industry. The effect of different synthesis parameters (Alkali type, alkali concentration, curing temperature and molar ratio etc.) on the strength and durability of geopolymer is reported.

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