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Potential of crystalline nanocellulose (CNC), as green reinforcing filler, has been evaluated for the preparation of natural rubber (NR) composites. CNC is derived from a natural source (ramie fiber) and its surface is modified with different organosilanes to strengthen the rubber‐filler interaction at the interface. It is found that, although at 2.5 phr (parts per hundred parts of rubber) loading of CNC the mechanical property of the NR composites is improved, it deteriorates at 5 phr loading. Surface modification of CNC by organosilanes is found very useful to overcome this issue. The modulus values at low strain become almost 1.5 to 2 times higher while tensile strength becomes 2.5 times higher for the modified CNC filled composites relative to those of CNC filled composites at 5 phr loading. These results are corroborated with a morphological study, where a very good state of dispersion of CNC particles is found in the surface‐modified CNC filled composites. Moreover, the particle size of CNC becomes almost half, in respect to that of unmodified CNC particles, upon surface modification by organosilane. The reinforcement effect delivered by CNC and surface‐modified CNC is also reflected by a small positive shift in Glass Transition Temperature (Tg) in differential scanning calorimetry study.

Klippel–Trenaunay syndrome and Sturge–Weber syndrome are rare disorders with neurologic and cutaneous signs of vascular origin. Phakomatosis pigmentovascularis represents the association of widespread, aberrant, and persistent nevus flammeus and pigmentary abnormalities. We describe a case with features suggestive of overlap between them. A ten-month-old boy presented with seizures, developmental delay, skin lesions on face, trunk and legs, buphthalmos and right lower limb hypertrophy. CT scan of head showed atrophy of brain and calcification. Our case had overlap of Klippel–Trenaunay syndrome and Sturge–Weber syndrome with phakomatosis pigmentovascularis

Materials such as cellulose and its derivatives are attracting growing attention worldwide to recognize their potential in responding to increasingly complex technological requirements. The rising demand for multifunctional materials may be fulfilled with controllable functionalities by using self-assembling techniques. Photonic stimuli-responsive materials based on cellulose can shift color reversibly when responding to external inputs. Cellulose nanocrystals (CNCs) are biorenewable materials that self-assemble themselves into a chiral nematic ordering exhibiting iridescent colors. The CNCs display unique optical features in response to environmental stimuli due to the structural coloration mechanism. This review summarizes the CNC-based multisensing photonic structures in response to external dopants. The inclusion of functional polymers, small molecules, or other optically active components into CNC precursors can enhance and stabilize their uniformity, allowing better stimuli interaction with the CNCs. This review reveals that cellulose-based nanomaterials are a potential candidate for designing advanced functional photonics materials in diverse applications for smart textiles, intelligent packaging, security coding, photonic papers, humidity sensors, etc., with some limitations to overcome.

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The organic photonic film is one of the important materials in optical, bioengineering, and sensing applications. It is a task to achieve excellent mechanical properties and foldability of the biopolymer composites having chiral nematic structures without sacrificing their iridescence. Herein, we have proposed an approach to preserve and lock the self-assembled cellulose nanocrystal (CNC) films based on agro-waste between the layers of a poly(lactic acid) (PLA)/polycaprolactone (PCL) biocomposite. The photonic properties of the composites were tweaked by doping with different organic acids (OAs). The addition of OAs into CNCs has resulted in the generation of flexible films. The multilayer films were studied for interfacial interactions in the form of spherulite interlocking between CNCs and polymer blends through polarized optical microscopy and differential scanning calorimetry analysis. Composite films exhibited high mechanical strength and also showed reflection from the UV region to the near-IR region. The composite films displayed good visual color-sensing properties with moderate antibacterial activity for Escherichia coli bacteria. Such ordered nanocellulose−polymer biocomposites fabricated by a facile layer-by-layer approach may assist the growth of obtained photonic films as candidate materials having implications in bio-optical engineering and packaging.

Hybrid composite films are largely preferred over neat films because of their superior thermal, mechanical, chemical, and hydrophobic properties. The hybrid composite film has a wide range of use, including space, defense, electronics, packaging, and engineering applications. Fabricating multifunctional hybrid composite films with biodegradable polymer and biodegradable filler such as cellulose nanocrystals has become popular in recent years as an alternative to conventional plastics. In this paper, hybrid hydroxylated boron nitride (BN) nanoparticles with CNC nano‐filer reinforced composite PVA films were fabricated. The obtained composite films were characterized for morphological, chemical, physical, thermal, and hydrophobic properties. The morphological analysis indicates that the hybrid nano‐filler was well dispersed in the poly(vinyl alcohol) (PVA) matrix. The reaction and hydrogen bond interactions between CNC and BN in composite films are confirmed by the Fourier transform infrared spectroscopy and x‐ray diffraction pattern. The contact angle method is used to confirm the enhancement of the hydrophobic property. The physical properties of the composite films and neat PVA film were analyzed by tensile test method using a universal testing machine. The thermal stability of the neat PVA film and the composite films were analyzed by the thermo‐gravimetric analysis method. The effect of hybridization of nanoparticles on the thermal, mechanical, and hydrophobic properties was studied. The hybrid composite film with enhanced properties allows it for multifunctional applications.